Publications
Graeme Gillespie, Arthur Rylah Institute
Peter Robertson, Wildlife Profiles Pty Ltd
Department of Natural Resources and Environment, September 1998
Critically Endangered (NRE 1998); Endangered (Tyler 1997); Endangered (Wildlife Act 1975); Endangered (Schedule 1 of Endangered Species Protection Act 1992); Endangered (Schedule 1 of NSW Threatened Species Conservation Act 1995); Vulnerable (ANZECC 1995); Threatened (Schedule 1 of Flora and Fauna Guarantee Act 1988).
The Spotted Tree Frog is considered critically endangered according to IUCN (1994) criteria (Robertson and Gillespie 1996). It has been listed as a threatened taxon on Schedule 2 of the Flora and Fauna Guarantee Act 1988 (SAC 1991a). It is considered to be vulnerable to extinction if the factors responsible for its decline continue to operate. In NSW the species is listed as Endangered, indicating that it is likely to become extinct unless the circumstances and factors threatening its survival or evolutionary development cease to operate.
Habitat Requirements and Limiting Factors:
The Spotted Tree Frog is confined predominantly to the north-west side of the Great Dividing Range between the Central Highlands in Victoria and Mt Koscuiszko in New South Wales. Survey results strongly suggest that the species has a limited and fragmented distribution and has suffered a significant decline during the past twenty years. Spotted Tree Frogs inhabit naturally-vegetated, rocky, swift-flowing upland streams in dissected mountainous country, between 200 and 1110 metres above sea level. Distribution along streams is patchy, most individuals being associated with loose rock substrates, rocky banks and riffles or cascades. Adjacent stream-side vegetation is also used for sheltering and basking. Eggs are deposited under large in-stream boulders, and tadpole development occurs within the stream.
Factors that limit the Spotted Tree Frog have been examined by Gillespie and Hollis (1996). Those that change or modify habitat characteristics in and adjacent to streams and in catchments of streams represent a threat to the ecology of Spotted Tree Frog. These include environmental factors (eg. short-term climatic variability) and anthropogenic factors (eg. introduced predators, increased stream sedimentation, vegetation clearing/modification, introduced plants and changes in water quality and quantity). Sheltering and/or foraging sites away from streams may also be affected by such disturbances. The factors responsible for the decline in the Spotted Tree Frog populations are currently thought to be those currently limiting the populations, although other factors will be investigated (eg. disease).
The Spotted Tree Frog populations are isolated, possibly indicating a much wider distribution in the past with a decline to present levels. The small size and isolation of these populations exposes them to risk of extinction from stochastic events, with little chance of natural recolonisation. The mechanisms of natural fluctuations in population numbers occurring as a result of yearly variations in weather patterns, stream flow rates, levels of predation and subsequent recruitment are yet to be investigated. However, populations do appear to experience extremely variable recruitment, and thus may be particularly vulnerable to further disturbances. Some catchments still supporting Spotted Tree Frogs have experienced various disturbances in the past, and may be able to tolerate low levels of these disturbances. However, populations have become extinct in the past, and may do so in the future if inappropriate levels of disturbance are allowed.
Recovery Plan Objectives, Criteria and Actions:
The long term objective is to improve the conservation status of the species so that it no longer meets the IUCN criteria for critically endangered or endangered, and can be listed in the vulnerable category within ten years, by increasing the effective population size of each wild population to over 200 individuals.
The objectives of this Recovery Plan and the criteria for successfully achieving the objectives (relative to 1997 values) are:
Specific objectivesCriteriaTasks
It is not anticipated that the Spotted Tree Frog will be removed from the National and State threatened species lists within the time frame of this Recovery Plan (5 years) because of the relatively long time to reproductive age of the species, its limited vagility, and the extremely variable recruitment to the adult population. Furthermore, the effects of some recovery actions (eg. roading rehabilitation to reduce sediment input) may not be apparent within the time frame of this plan.
The costs of implementing this Recovery Plan, based on 1998 estimates, are summarised below for each financial year. ($000s/year)
|
Action |
1998/99 |
1999/00 |
2000/01 |
2001/02 |
200203 |
Total |
|||||
|
TC |
ESP |
TC |
ESP |
TC |
ESP |
TC |
ESP |
TC |
ESP |
||
|
1 |
5 |
1 |
5 |
1 |
5 |
1 |
5 |
1 |
5 |
1 |
25 |
|
2 |
30 |
19.5 |
30 |
19.5 |
30 |
19.5 |
30 |
19.5 |
30 |
19.5 |
150 |
|
3 |
5 |
5 |
3 |
10 |
|||||||
|
4 |
4 |
4 |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
8 |
|
5 |
4 |
4 |
20 |
20 |
20 |
20 |
44 |
||||
|
6 |
15 |
10 |
15 |
||||||||
|
3.7.1 |
6 |
4 |
6 |
||||||||
|
3.7.2 |
93 |
73 |
30 |
20 |
60 |
50 |
40 |
30 |
5 |
5 |
228 |
|
8 |
2.5 |
2.5 |
2.5 |
2.5 |
5 |
||||||
|
9 |
40 |
10 |
40 |
30 |
20 |
10 |
20 |
10 |
20 |
10 |
140 |
|
10 |
25 |
20 |
25 |
20 |
6 |
4 |
6 |
4 |
62 |
||
|
11.1 |
52.5 |
2.5 |
55 |
||||||||
|
11.2 |
2.5 |
2.5 |
2.5 |
2.5 |
2.5 |
12.5 |
|||||
|
11.3 |
2 |
1 |
1 |
1 |
1 |
6 |
|||||
|
11.4 |
2 |
2 |
4 |
||||||||
|
11.5 |
3 |
2 |
2 |
2 |
2 |
11 |
|||||
|
11.6 |
2 |
1 |
1 |
1 |
1 |
6 |
|||||
|
11.7 |
5 |
5 |
2 |
2 |
2 |
16 |
|||||
|
11.8 |
1 |
1 |
1 |
1 |
1 |
5 |
|||||
|
11.9 |
6 |
6 |
2 |
2 |
2 |
18 |
|||||
|
12.1 |
3 |
3 |
3 |
3 |
3 |
15 |
|||||
|
12.2 |
4 |
4 |
8 |
||||||||
|
13.1 |
6 |
2 |
4 |
1 |
2 |
2 |
2 |
16 |
|||
|
13.2 |
4 |
4 |
4 |
4 |
4 |
20 |
|||||
|
14.1 |
8 |
8 |
8 |
8 |
8 |
40 |
|||||
|
14.2 |
3 |
3 |
3 |
3 |
3 |
15 |
|||||
|
14.3 |
5 |
5 |
|||||||||
|
14.4 |
5 |
5 |
|||||||||
|
Total |
293.5 |
112 |
212.5 |
116 |
192.5 |
121.5 |
153.5 |
85.5 |
98.5 |
40.5 |
950.5 |
TC = Total cost
ESP = Endangered Species Program funds required
TC-ESP = NRE plus other contribution
Research into the Spotted Tree Frog will also assist in the conservation of other riverine frog species in Australia, in particular the Blue Mountains Tree Frog Litoria citropa, Leaf Green Tree Frog L. phyllochroa, Lesueur's Frog L. lesueuri, Booroolong Frog L. booroolongensis, Tablelands Frog L. subglandulosa, Pearson's Green Tree Frog L. pearsoniana and Stuttering Frog Mixophyes balbus.
The sites of extant populations of this frog are often on streams of high conservation value for other reasons. Other threatened stream or riparian flora and fauna (eg. Barred Galaxias, Mountain Galaxias, Central Highlands Spring Crayfish) exist in catchments supporting Spotted Tree Frogs. A broad approach to catchment protection and management aimed at frog conservation will enhance the conservation of these other values.
A number of threats to in-stream fauna have been recognised as Potentially Threatening Processes under the Victorian Flora and Fauna Guarantee Act 1988. These include: increased sediment input to streams (SAC 1991b); changes to temperature (SAC 1992a) and flow regimes (SAC 1992b) of streams; the introduction of live fish outside their natural range (SAC 1992c); the input of toxic substances to streams (SAC 1993); and the degradation of riparian vegetation (SAC 1995). All of these could affect populations of Spotted Tree Frogs.
At present, there is no evidence to suggest that wider conservation problems (eg. greenhouse, ozone depletion) may be affecting Spotted Tree Frog populations.
The Spotted Tree Frog (Litoria spenceri Dubois 1984) is a medium-sized species in the Family Hylidae. Females may attain 61 mm (snout-vent length) while males are smaller, attaining 50 mm (Watson et al. 1991). The dorsum is highly variable; it may be pale brown, bright green to olive-grey, with or without darker blotches, usually with numerous small raised `warts'. The ventral surface is pale and granular, often becoming flushed with pale orange towards the rear and on the underside of the hind limbs. Toes and fingers are distinctly flattened, with the discs moderately expanded; the fingers have distinct basal webbing and the toes are fully webbed. The head is broad and a distinct fold is present above the indistinct tympanum.
The tadpole is free swimming. The body is elongated and flattened, and individuals reach a total length of 40 mm prior to metamorphosis. The tail is moderately thick and has a rounded tip. The eyes are dorso-lateral and the mouth is ventral. The oral disc is large relative to other closely-related species, and the oral papillae have a wide anterior gap. There are two rows of anterior labial teeth and three posterior rows. The body is dark brown to black above, with fine silver chromatophores extending onto the flanks. Darker spots may be present on the dorsal surface. Ventral surface is darkly pigmented. Tail fin and muscle are covered with fine melanophores (Hero et al. 1995).
Extensive surveys of the distribution and abundance of the Spotted Tree Frog have revealed the species to be extant at only thirteen discrete populations - eleven in Victoria and two in New South Wales (Watson et al 1991; Gillespie and Hollis 1996; Hunter 1996 Hunter and Gillespie in press; Gillespie 1998). These occur in the catchments of 21 streams (several populations occurring around the confluences of streams). During the surveys, populations could not be found in four streams in which they had previously been recorded. The surveys failed to detect Spotted Tree Frogs at historical sites on a further four streams, but located the species elsewhere along those streams. As a result of these surveys we now have a very good understanding of the status and distribution of this species.
The Spotted Tree Frog is confined predominantly to the north-west side of the Great Dividing Range between the Central Highlands in Victoria and Mt Kosciuszko in New South Wales. Survey results strongly suggest that the species has a limited and fragmented distribution and has suffered a significant decline during the past twenty years.
Figure 1. Distribution of the Spotted Tree Frog (Litoria spenceri). Closed circles indicate sites where populations of L. spenceri are currently known to occur (Gillespie and Hollis 1996; Hunter and Gillespie in prep.). Open circles are localities at which L. spenceri was recorded historically. Numbers refer to each stream in which L. spenceri has been recorded: (1) Still & White Ck; (2) Taponga R.; (3) Big R. (Eildon) R.; (4) Goulburn R.; (5) Black R.; (6) Thompson R.; (7) Jamieson R. (North Branch); (8) Howqua R.; (9) King R.; (10) Buffalo Ck; (11) Buckland R.; (12) Wongungarra R.; (13) West Kiewa R.; (14) Snowy Ck; (15) Lightning Ck; (16) Bundarra R.; (17) Big R. (Mitta Mitta); (18) Wheeler Ck.; (19) Bogong Ck.; (20) Murray R.; (21) Snake Ck and tributaries.
Table 1.Streams in which Spotted Tree Frogs have been recorded, and the current status of their populations. Population size estimates are extrapolated from known actual densities of adults at two sites, repeated monitoring over the past five years, and known distribution of potentially suitable habitat. (SF - State Forest; SP - State Park; NP - National Park)
Population/StreamPop. SizePopulationCatchmentYear of Record
(adults)StatusStatusFirstLast
Thompson River-Presumed ExtinctSF19711971
Buffalo Creek-Presumed ExtinctNP19791983
King River-Presumed ExtinctSF/NP19771977
Buckland River-Presumed ExtinctSF/NP19611961
Howqua River~ 640DeclinedSF/NP19721996
Big River (Eildon)< 25DeclinedSF19791993
Snowy/Lightning Crks.~ 1090Possibly declinedSF19581996
Goulburn/Black Rivers~ 1550DeclinedSF19611996
Snake Creek~ 490UnknownSF19971998
Jamieson River~ 1100Possibly declinedSF/NP19921992
Wongungarra River~ 390No apparent declineSF19851996
Big River (Mitta Mitta)~ 870UnknownSF/NP19831996
Taponga/Still/Whites Crks.~ 670DeclinedSF/SP19891996
Bundarra River< 200UnknownSF/NP19941994
Wheeler Creek~ 950UnknownSF19931994
West Keiwa River< 20Possibly declined SF/NP19931996
Indi River (NSW)<25DeclinedNP19961996
Bogong Creek (NSW)<50DeclinedNP19751996
1.3.1 Breeding Habitats and Microhabitats
Spotted Tree Frogs inhabit naturally-vegetated, rocky, swift-flowing upland streams in dissected mountainous country, between 200 and 1110 metres above sea level. Frog populations are generally in areas with limited access and disturbance. Distribution along streams is patchy, most individuals being associated with loose rock substrates, rocky banks and rapids (Gillespie 1997b). Adjacent stream-side vegetation is also used for sheltering and basking. Eggs are deposited under large in-stream boulders. Tadpole development occurs within the stream (Hero et al 1995), in shallow pools or shallow margins of streams (Gillespie 1997b).
1.3.2 Non Breeding Habitats and Microhabitats
The full range of habitats used by the species is unknown - other species of riparian tree frogs range widely from streams during the non-breeding period. Spotted Tree Frogs may utilise similar off-stream habitats. The stream environment is used by this species from October to May - it is not known what habitats are used at other times.
Disturbance which may result in changes to the physical or biotic habitat in, and adjacent to, streams include: roading, timber harvesting, eductor dredging, human recreational disturbance, weed invasion, predation by exotic animals (including introduced fish), impoundments, herbicides, inappropriate fire regimes and grazing.
Important concerns include: changes in flow rates, which may effect the viability of eggs or the survivorship of tadpoles; increases in sediment levels, which may effect the availability of egg-deposition sites or the survivorship of tadpoles; and predation of tadpoles by introduced fish, which may reduce or preclude recruitment to the adult population. The potential role of disease organisms has yet to be determined.
The Spotted Tree Frog has been the subject of intensive research since 1994, and many details of its life history are now well understood.
1.4.1 Calling Activity, Oviposition and Early Development
Adult Spotted Tree Frogs are active in the stream environment from early October to late April, with some variation between seasons and between different sites. They may be active by day or night, again with some difference between sites in diel activity patterns - for instance, adult frogs are more active during the day at Bogong Creek, but appear to be more active at night at Taponga River. Juveniles are mostly diurnal at all sites. Calling activity takes place when weather conditions are suitable between late October and late December. The male advertisement call has been described by Watson et al (1991). Oviposition has been recorded between late November and the end of December. The larvae develop within the stream during summer and autumn, with metamorphosis occurring between mid-February and late March (Gillespie 1997b). There is no evidence to suggest that tadpoles can over-winter in the stream.
1.4.2 Population Dynamics and Demography
Clutch sizes for L. spenceri are highly variable, ranging from 278 to 928, with larger clutch sizes in low altitude populations (mean = 860) than high altitude populations (mean = 482) (Gillespie unpubl. data). Of four riverine species examined Litoria spenceri has the smallest clutch size to body size ratio.
The technique of age determination by skeletochronology has been refined for Spotted Tree Frogs such that reliable age estimates are now possible. This technique has provided important data on the life history of this species, which, combined with mark-recapture data, has provided information on population age structure, age to sexual maturity, longevity and age-specific mortality.
Age structure profiles, combining skeletochronological age estimates with those of frogs of known age from mark-recapture, have been generated for Bogong Creek and for Taponga River/Still Creek. Notable differences in population structure have been observed between Bogong Creek and Taponga River. At Bogong Creek the species is relatively long-lived, with a significant proportion of individuals living longer than 9 years. The oldest individual detected so far is a 13 year old female. At Bogong Creek the age to sexual maturity is 3-4 years for males and 5-6 years for females. In contrast, at Taponga River the maximum age detected for either sex is eight years. Most males are reaching sexual maturity at two years, although some may take three years. Females may be sexually mature as young as three years but it appears that most probably take four years. The ages measured for individuals from the Goulburn River Howqua Rivers are similar to the Taponga River population. The differences in growth rate and longevity between Bogong Creek and Taponga River are consistent with other studies of poikilotherms, which have found that higher altitude populations tend to be slow-growing and live longer than lower altitude populations. However, these have significant implications for the population dynamics of the species.
Population age structure data, combined with annual recruitment and survival estimates from transect censuses, have been used to estimate age-specific mortality. Estimates of juvenile mortality are high up until 2-3 years of age in both populations. However, juvenile mortality appears to be substantially greater at Bogong Creek. Survival beyond age 3 of subadults and adults to maximum age is relatively high. Age to sexual maturity and mean clutch size, provide estimates of reproductive output along transects. Despite the potentially higher clutch size of females at Taponga, earlier maturity and higher juvenile survival, net recruitment and adult population density are much lower. This is most likely explained by much higher mortality of egg or tadpole stages than that at Bogong Creek.
Mark-recapture data for both Bogong Creek and Still Creek indicate very high site fidelity for L. spenceri, with many individuals remaining on the transect after two years. The average net movements of adults and juveniles at Bogong Creek during one season is less than 40 metres. This examination is biased towards the movement patterns of individuals remaining on survey transects; however, searches above and below transects for several hundred metres have located few marked individuals. The maximum movement of any individual detected so far is 347 metres. Examination of short-term movement patterns of individuals indicates that more movement along streams may be occurring at the beginning and end of the active season.
The results of radio tracking are consistent with the sedentary patterns observed during the breeding season as indicated by mark-recapture data. Most movements along the stream for radio-tracked frogs were less than 10 metres in 4 - 5 weeks, and few frogs moved more than 100 metres in this time. It has not been possible to track frogs through the autumn to their over-wintering refugia. Nevertheless, radio tracking has provided important data on movement patterns and habitat use of L. spenceri over short time periods (1 - 4 weeks), which indicate that the frogs remain in the vicinity of the stream environment and are unlikely to venture great distances away from the stream during the breeding season.
1.4.4 Competition - Food and Sediment Effects
Experiments examining the effects of density dependent competition, sediment and food availability upon growth and survival of Spotted Tree Frog tadpoles have been conducted (Gillespie 1997b). Intra-specific density dependent competition was more pronounced in Spotted Tree Frogs compared to inter-specific competition between Spotted Tree Frogs and Leaf Green Tree Frog or Lesueur's Frog. Assymetrical competition was also apparent between these species in favour of Spotted Tree Frog tadpoles. Spotted Tree Frog tadpoles were significantly disadvantaged by reduced food availability which was exacerbated by reduced availability of algae and increased sediment loads.
These results indicate that increased sediment loads have the capacity to influence populations by reducing tadpole growth, and therefore, size and time of metamorphosis. Other studies have shown that reduced size at metamorphosis reduces survival. Delayed metamorphosis is also likely to have severe effects in some seasons by delaying tadpoles leaving the stream before the end of summer. Sediment may also reduce the availability of oviposition sites; however, this has not been quantified.
Predation of the eggs and larvae of riverine amphibians by fish has been shown to be an important factor affecting frog populations (Brockelman 1969; Calef 1973; Heyer et al 1975; Morin, 1981; Wilbur 1972). Trials of the palatability of tadpoles of the Spotted Tree Frog and other riverine frogs to Mountain Galaxias, Two-spined Black Fish, and Brown Trout have been undertaken. These four species of fish occur in wide sympatry with L. spenceri. Results indicate that L. spenceri L. phyllochroa, L. citropa and L. lesueuri tadpoles are unpalatable to native fish. However, except for L. lesueuri, introduced trout preyed heavily on tadpoles of all species (Gillespie 1997b; Gillespie in review).
In addition to the palatability trials, stream enclosure experiments have been conducted with L. spenceri and L. phyllochroa tadpoles and Rainbow Trout. The results indicate that, despite the availability of alternative food sources for the trout and sheltering sites amongst rocks and detritus for tadpoles, predation from trout has the potential to significantly affect tadpole populations of these two frog species (Gillespie 1997b; Gillespie in review).
Predation by trout is potentially a dominant factor in the decline of Spotted Tree Frog populations. The presence of trout in all streams still supporting Spotted Tree Frog populations places them under further risk of decline or extinction.
The potential for invertebrate predators (eg. odonates or ditiscid beetle larvae) of tadpoles to effect Spotted Tree Frog populations is considered low. Similarly, the high survival of adult Spotted Tree Frogs would suggest that predation of adults by vertebrates (eg. snakes) is probably not significant.
A population genetic study, using allozyme electrophoresis, has been conducted. Individuals from eight populations throughout the range of the Spotted Tree Frog were examined: Taponga River, Goulburn/Black Rivers, Howqua River, Wongungarra River, Snowy Creek, Big River (Mitta Mitta) and Bogong Creek. No fixed allelic differences were detected, but substantial variation in allelic frequencies was found between adjacent populations. In addition, some populations contain unique alleles. Preliminary analyses indicate substantial population genetic subdivision between populations in different stream systems (Gillespie 1997a). A major subdivision is present between populations in the Goulburn basin and others to the east. These findings suggest that remaining populations of L. spenceri are quite insular. Natural recolonisation of adjacent streams is highly unlikely.
Investigations of populations of Leaf Green Tree Frog and Lesueur's Frog occurring sympatrically with the Spotted Tree Frog indicate that they may also have undergone population declines (although not as severe as those of the Spotted Tree Frog), with introduced trout perhaps a major factor.
The Spotted Tree Frog is recognised as endangered in Victoria (NRE 1998) and New South Wales (Schedule 1 of Threatened Species Conservation Act 1995), and has undergone a significant decline both in number and size of populations. Revised assessments of the conservation status according to IUCN (1994) criteria listed the species as critically endangered (Robertson and Gillespie 1996). Tyler (1997) lists the species as endangered.
The Spotted Tree Frog appears to have suffered a general decline in distribution and abundance. All extant populations appear under threat from various disturbances - many are small, and some have declined. Analysis of disturbance histories at individual sites indicates an association between the contraction in distribution and a number of human-induced disturbances to forest and riparian habitats (Gillespie and Hollis, 1996). Frog populations are isolated, possibly indicating a much wider distribution in the past with a decline to present levels.
From the total of seventeen discreet populations on different streams, four are thought to be extinct. Of the remaining thirteen, frogs have disappeared from historical sites at a further four streams, although they persist elsewhere in those catchments. Furthermore, one of the populations previously recognised as among the largest and most secure has recently (1996/1997) undergone a precipitous decline to the verge of extinction. Surveys of the Big River (Eildon) and Indi Rivers in 1997 and 1998 have also failed to locate the species.
The small size and isolation of most populations exposes all to risk of extinction from stochastic events, with little chance of natural recolonisation. All extant populations have the added threat of various disturbances.
Potentially threatening processes which have been implicated in the decline of this species by Gillespie and Hollis (1996) involve disturbance in and adjacent to streams and in catchments of streams. Sheltering and/or foraging sites away from streams may also be affected by such disturbances.
Threats from disturbances which may result in changes to water flow, water quality, sedimentation or other changes to the physical or biotic habitat include: roading, timber harvesting, eductor dredging, human disturbance (eg. recreation, angling), weed invasion, predation by exotic animals (including introduced fish), impoundments, herbicides, inappropriate fire regimes and possibly grazing.
Important concerns include: changes in flow rates, which may effect the viability of eggs or the survivorship of tadpoles; increases in sediment levels, which may effect the availability of egg-deposition sites or the survivorship of tadpoles; and predation of tadpoles by introduced fish, which may reduce or preclude recruitment to the adult population.
Some catchments still supporting Spotted Tree Frogs have experienced various disturbances in the past, and may be able to tolerate low levels of these disturbances. However, populations have become extinct in the past, and may do so in the future (with little or no possibility of recolonisation from other populations) if inappropriate levels of disturbance are allowed.
Disease has been implicated as a possible explanation for the decline and disappearance of some amphibians (eg. Bradford 1991; Blaustein et al. 1994; Trenerry et al. 1994; Laurance et al. 1996; Berger et al. 1998; Lips 1998). However, in very few studies has the demise of an amphibian population been positively attributed to a pathogenic species (eg. Blaustein et al. 1994), with most links remaining circumstantial or speculative. In many cases, the disease hypothesis is largely supported by the discovery of moribund frogs only, with no rigorous assessment to directly link pathogenic species with the demise of amphibian taxa.
Recently a fungus has been identified in the skin of some Australian and South American frog species (Berger et al. 1998). Some populations of these species infected with this fungus have declined. This chytrid fungus is able to kill frogs in the laboratory. However, it is not known if this fungus is responsible for the population declines or a symptom of other environmental stress. Prior to the decline of the Spotted Tree Frog population at Bogong Creek, several dead and one moribund frog were located. The moribund frog was found to be infected with this tetrad fungus. During the summer of 1997/98, several dead and moribund Spotted Tree Frogs were located in Taponga River and Snake Creek. These, along with specimens from the Black River, were also found to be infected with the chytrid fungus. The impact of these infections on these populations is not yet known. The fungus may be an opportunistic natural pathogen which is normally innocuous, but is able to kill frogs under certain environmental conditions. Alternatively this fungus may be a novel pathogen in populations of Australian frogs. The potential for disease to be a factor in the decline of the Spotted Tree Frog will be examined.
At present, there is no evidence to suggest that wider conservation problems (eg. greenhouse, ozone depletion) may be affecting Spotted Tree Frog populations.
1.6 Existing Conservation Measures
The Spotted Tree Frog is currently listed as endangered on Schedule 1 of the Endangered Species Protection Act 1992. This Act provides a framework within which States and Territories can seek assistance from the Commonwealth for the preparation and implementation of Recovery Plans (this document). The Spotted Tree Frog is listed on the Action Plan for Australian Frogs (Tyler 1997) as an endangered species. The objectives outlined in that document are: to determine habitat needs of the species; to identify causes of the observed decline, and; to review management to conserve habitat and minimise impact of factors responsible for decline.
The Spotted Tree Frog is protected under the Victorian Wildlife Act 1975 as an endangered species. It is currently listed as a threatened species under Schedule 2 of the Victorian Flora and Fauna Guarantee Act 1998. In accordance with that Act, an Action Statement for the species has been prepared by the Victorian Department of Natural Resources and Environment (1997), outlining the actions to be taken to ensure the species long term survival in that State. The Action Statement is due for revision in 2002. The major intended management actions listed in the Statement comprise: (a) Research, survey and monitoring, (b) off-stream and in-stream habitat protection, (c) pest plant and animal management, (d) critical habitat definition, and (e) public education.
The Spotted Tree Frog is protected in NSW under the National Parks and Wildlife Act 1974 (NPW Act) and the Threatened Species Conservation Act 1995 (TSC Act). Under the TSC Act the preparation of Recovery Plans is mandatory for all threatened species, endangered populations and endangered communities..
Approved Recovery Plans are statutory documents. Ministers and public authorities are to take any appropriate action available to them to implement those measures included in a recovery plan for which they are responsible and must not make decisions that are inconsistent with the provisions of a recovery plan without the agreement of the appropriate authority. Recovery Plans are to be taken into account by consent or determining authorities when they are considering development applications under Parts 4 or 5 of the Environmental Planning and Assessment Act 1979.
Watson et al. (1991) consolidated all information on Spotted Tree Frogs at the time, and developed a management strategy for the species. Since that time there have been extensive surveys throughout the range of the Spotted Tree Frog (Gillespie 1992; Gillespie and Hollis 1996; Hunter 1996; Gillespie 1998; Hunter and Gillespie in press), and intensive research into the biology of the species (Gillespie 1993, 1997a,b, 1998; Gillespie and Robertson 1996a,b; Robertson and Gillespie 1996,) with funding support from the Endangered Species Program of the Australian Nature Conservation Agency (now Environment Australia).
The following actions have been implemented.
Nearly all streams in eastern Victoria and southern New South Wales considered to support suitable habitat for the Spotted Tree Frog have been surveyed, between 1988 and 1998 (Watson et al. 1991; Gillespie and Hollis 1996; Gillespie 1998; Hunter and Gillespie in press).
Fish surveys have been conducted at sites in all streams that Spotted Tree Frogs have been recorded (Gillespie 1998; M. Lintermans unpublished data).
The frog's advertisement call has been recorded; its larvae have been described and other aspects of its biology determined (Watson et al. 1991; Hero et al. 1995; Gillespie 1997b). The egg deposition sites have been determined (1994). Spotted Tree Frogs have been maintained at the Melbourne Zoological Gardens and The Amphibian Research Centre (ARC) for development of captive husbandry techniques (1990-98).
Intensive monitoring and ecological study of two populations has been carried out for up to six years (Gillespie 1993; Gillespie and Hollis 1996, Gillespie 1997b). Using mark-recapture techniques, recruitment, growth, survivorship, mortality, activity patterns, habitat use, movement patterns and reproductive behaviour of Spotted Tree Frogs and any other species present has been examined. Radio tracking techniques have been employed for studying sheltering sites, movement patterns and dispersal of Spotted Tree Frogs.
Habitat use, activity patterns, and development of tadpoles has been examined.The palatability of tadpoles of Spotted Tree Frogs and other riverine species to native and introduced fish has been determined. Experiments examining the effects of density dependent competition, sediment and food availability upon growth and survival of Spotted Tree Frog tadpoles were conducted in stream enclosures.
Skeletochronology has been used to derive age estimates for adult frogs, which, when augmented by population age-profiles obtained from mark-recapture data, have enabled some assessment of age-specific mortality for use in demographic modelling.
Samples of material collected from eight Spotted Tree Frog populations have been examined by allozyme electrophoresis - results indicate that each population is genetically distinct, suggesting long isolation times and the potential for local adaptation.
Preliminary investigations have been conducted into the role of disease in the decline of Spotted Tree Frog populations. Dead and moribund frogs collected from various populations during the course of other research have been forwarded for pathological examination to the CSIRO Animal Health Laboratories in Geelong. Tissue sections prepared for skeletochronology have also been examined. Chytrid fungus recently identified from several other declining frog species has been identified in Spotted Tree Frogs from Bogong Creek prior to the decline, Taponga River, Snake Creek and Goulburn River. This fungus has also been detected in specimens of Lesueur's Frog from two streams in Victoria. The significance of this fungus in the decline of the Spotted Tree Frog is not yet known.
As part of the Regional Forests Agreement process, an investigation of the relationship between stream-side buffer and filter strips and in-stream habitat and macroinvertebrates was commenced in 1997. This study will examine the effectiveness of these buffers and filter strips in protecting the stream ecosystem from the impact of sedimentation arising from forest harvesting practices. The findings of this study should assist in assessing the effectiveness of current prescriptions for protecting Spotted Tree Frog habitat values in logging areas.
Sixteen long-term monitoring transects have been established and monitored, to detect any seasonal and yearly fluctuations in population numbers (1994- 98). A further six monitoring transects were established in the remaining populations in 1998.
1.6.4 Population Viability Analysis (PVA)
A Population and Habitat Viability workshop was conducted in August 1996. The modelling, based upon preliminary life history and demographic information, indicated that the level of recruitment from the larval phase was a particularly important determinant of population size and probability of extinction, and that management should attempt to enhance survivorship through this phase. Clear identification of threats, suggested measures for threat amelioration, and guidelines for genetic investigations were produced. A report from this workshop is in preparation (see also Action 3.8).
Specific research and management recommendations, with indications of their priority for recovery of the species, were formulated during the workshop. It was recommended to:
· implement a trial project to evaluate the effects of excluding fish on increasing the production of metamorphs. This may also immediately benefit treated populations by reversing further declines.
· investigate captive or artificial on-stream management as a means of rapidly stabilising or increasing wild populations
· investigate with fishing groups (both local and state) their willingness to participate in further studies of fish predation on Spotted Tree Frog and management actions.
· assess the need and feasibility of fish exclusion or control works at all frog populations.
· identify at all frog sites all significant sources of sedimentation that require urgent attention and implement remedial works as a priority action.
· implement an additional auditing program aimed specifically at ensuring that roading and forestry activities (including State Forest and National Parks) are conforming with prescriptions detailed in the draft Action Statement and Central Highlands Forest Management Plan.
· if predator control results in increases in frog population sizes, consider the necessity and potential to increase the carrying capacity of all frog habitats.
· immediately conduct further modelling using VORTEX and other models, suited to amphibian life histories, with additional time spent on investigating the impact of catastrophic events on population viability and repeat the modelling of all scenarios when the additional data (listed below) have been collected.
· collect data on factors affecting egg, tadpole and juvenile survival.
· determine the variation in reproductive output between individual frogs, using genetic techniques.
· investigate the spatial heterogeneity of populations (metapopulation dynamics) using mark-recapture, radio tracking and genetic techniques.
· determine if the Spotted Tree Frog is composed of multiple taxonomic groups, using genetic techniques
· determine the genetic population unit, defined as the areas within which there is random mating, and the genetically viable effective population size for all populations, using genetic techniques.
· continue monitoring of all populations so that population dynamics and environmental variation can be better estimated.
A three-year moratorium (until June 1996) on logging in the Wongungarra River above Mount Selwyn Creek was instigated in 1993, subject to research into the effects of timber harvesting and associated roading activities on Spotted Tree Frogs. No timber harvesting has occurred since 1996, and future management for this area will be decided through the North-East forest management planning process, taking due account of the Spotted Tree Frog.
Training of regional NRE staff in searching techniques for Spotted Tree Frogs was undertaken. Fencing and revegetation works have been undertaken, and information displays erected in areas of high recreational pressure.
Increased policing of illegal eductor dredging operations was instigated and legal action was undertaken against operators. Eductor dredging was reviewed in 1993 (ENRC 1994), and is not permitted in Victoria.
Independent advice was sought and recommendations received from a consultant (O'Shaughnessy and Associates 1995) on reducing risk from sediment, including detailed prescriptions for habitat management during roading and timber harvesting operations, together with remedial works required.
A study of the feasibility of trout eradication and exclusion has been conducted at Bogong Creek, Lightning Creek, Buffalo Creek and Still/White Creeks (Saddlier and Gillespie 1997).
An Action Statement has been prepared in Victoria under the Flora and Fauna Guarantee legislation. It includes detailed prescriptions for management of the habitat of the Spotted Tree Frog, some of which have been adopted prior to official release of the document.
A National Recovery Team has been established to oversee and direct research and management of the species. Representatives from NRE, NSW National Parks and Wildlife Service, University of Canberra, University of Melbourne, LaTrobe University, Biodiversity Group, Environment Australia and conservation groups are included. The Recovery Team has overseen the research program and preparation of the Victorian Action Statement, which includes detailed prescriptions for management of the habitat of the Spotted Tree Frog.
1.6.7 Public Awareness and Education
Conservation of the Spotted Tree Frog was promoted by an education exercise targeted at NRE staff and other interest groups. Educational information was disseminated; a poster was produced (CFL habitat series no. 4); an identification pamphlet and sighting report form was circulated, and extensive media promotion was undertaken.
The long term objective is to secure the species from the threat of extinction by:
(a)ensuring long-term survival of genetically viable populations across the geographic range,
(b)increasing the populations to a level predicted by PVA analyses to be adequate for long-term viability.
This may be achieved by improving the conservation status of the species so that it no longer meets the IUCN (1994) criteria for critically endangered or endangered, and can be listed in the vulnerable category within ten years, by increasing the effective population size of each wild population to over 200 individuals.
The medium-term and short-term objectives within the time-frame of this plan (5 years) are:
ESP = Environment Australia, Endangered Species Program;
NRE = Victorian Department of Natural Resources and Environment
NSW NP&WS = New South Wales National Parks and Wildlife Service
SMA = Snowy Mountains Authority
RFA = Regional Forest Agreement (funding support)
3.1 Action 1 Long-term Monitoring
An understanding of what constitutes natural or abnormal fluctuations in Spotted Tree Frog populations can only be achieved by monitoring the abundance of populations over considerable periods, to establish the extent of population stability, to detect any adverse effects of environmental disturbance, and to assess the effects of management activities. For amphibians generally, it has been suggested that the length of monitoring time should be at least one generation (Pechmann and Wilbur 1994). The longevity of the Spotted Tree Frog is over 10 years; monitoring should continue for at least this time, but is desirable until recovery is assured, and perhaps even longer where threats persist.
A rigorous program to monitor some Spotted Tree Frog populations has been implemented during the past four years. This has been expanded to include all extant sites twice yearly. Similarly, fish populations will be monitored at selected sites annually to investigate any responses of frog recruitment to introduced fish and their control measures. (Costings for the fish monitoring component are included within Action 3.7.2)
Funding is required from ESP to contribute towards expanding the existing monitoring program to include all sites. Monitoring will be conducted by NRE personnel. (Note that the costing does not include salaries of NRE personnel, just running costs to enable the field work to proceed.)
Responsibility: NRE, NSW NP&WS
|
Costs |
1998 |
1999 |
2000 |
2001 |
2002 |
|
NRE |
$3000 |
$3000 |
$3000 |
$3000 |
$3000 |
|
NSW NPWS |
$1000 |
$1000 |
$1000 |
$1000 |
$1000 |
|
ESP |
$1000 |
$1000 |
$1000 |
$1000 |
$1000 |
|
Total cost |
$5000 |
$5000 |
$5000 |
$5000 |
$5000 |
3.2 Action 2 Intensive Population Monitoring
Intensive monitoring involving mark-recapture along fixed transects has been conducted at Bogong Creek for three years and Taponga River for six years. These studies have yielded invaluable demographic data, and have shown a high degree of variability of key demographic parameters. (See Gillespie and Robertson 1996b; Gillespie 1997b.) It is highly desirable to continue the intensive monitoring at these sites, to further investigate demographic parameters and to determine the factors responsible for their variability. On-going monitoring of the Bogong Creek population, which underwent a precipitous decline in 1996/97, is required to assess the on-going status and possible recovery of this population. The Still/White Creek population has been considered appropriate for trials on reduction of trout predation (Gillespie and Saddlier 1997) (see Actions 3.7.3 and 3.7.4), and as such must be monitored intensively to measure responses of the frog population.
Funding is required from ESP to enable further intensive monitoring to proceed. This will be undertaken by a suitably experienced consultant(s) under the supervision of NRE. If funding is available from NSW NP&WS, then requirement for ESP contribution could be reduced,
Responsibility: NRE, NSW NP&WS, Consultant
|
Costs |
1998 |
1999 |
2000 |
2001 |
2002 |
|
NRE |
$10500 |
$10500 |
$10500 |
$10500 |
$10500 |
|
ESP |
$19500 |
$19500 |
$19500 |
$19500 |
$19500 |
|
Total cost |
$30000 |
$30000 |
$30000 |
$30000 |
$30000 |
To determine the area in which management activities will be undertaken, and to provide information on the size of populations for modelling purposes, it is important to know exactly where the populations occur. While extensive and intensive surveys have been undertaken in eastern Victoria and south-eastern New South Wales in recent years (Gillespie 1993, Gillespie 1993, Gillespie and Hollis 1996, Hunter 1996, Gillespie 1998; Hunter and Gillespie in prep.), some streams supporting potentially suitable habitat require further survey (eg. Mt Selwyn Creek and Humphrey River in Victoria, Swampy Plains catchment in NSW)). The limits of extant populations are understood for most populations, but some require further survey. In particular, the occurrence down-stream from Bourke's Gorge on Bogong Creek, where the species has recently declined, is unknown. In addition, further information is required on the distribution and abundance of other riverine species with relation to the distribution of introduced trout.
Researchers who conduct the surveys must have a good knowledge of the biology and ecology of the Spotted Tree Frog and be experienced with the methodologies previously employed. Funds have been allocated from the RFA process for this action.
Responsibility: NRE, NSW NPWS, Consultant
|
Costs |
1998 |
1999 |
2000 |
2001 |
2002 |
|
NRE |
$3000 |
$3000 |
0 |
0 |
0 |
|
NSW NPWS |
$2000 |
$2000 |
0 |
0 |
0 |
|
ESP |
0 |
$3000 |
0 |
0 |
0 |
|
Total cost |
$5000 |
$8000 |
0 |
0 |
0 |
3.4 Action 4 Skeleto Chronology
To investigate population viability and possible threats to the Spotted Tree Frog, information about the population demography of the species is essential. Many demographic parameters may be examined by intensive monitoring in conjunction with skeletochronology to determine age of individuals. The Spotted Tree Frog has proven to be a suitable species for the application of skeletochronological techniques (Gillespie 1997b), and much valuable information has been obtained from analyses to date. Over 150 samples have been examined; however a significant proportion of the sample population from Bogong Creek have not yet been examined, and further samples have been collected from the Taponga River population. These samples need to be examined to complete analyses of population age structure.
Samples are processed under the supervision of an histologist using equipment and facilities provided by a university. Funding is required from ESP to complete the processing of existing samples, and to allow for continuation of sampling from the future intensive transect monitoring.
Responsibility: NRE,Consultant
|
Costs |
1998 |
1999 |
2000 |
2001 |
2002 |
|
NRE |
0 |
0 |
0 |
0 |
0 |
|
ESP |
$4000 |
$1000 |
$1000 |
$1000 |
$1000 |
|
Total cost |
$4000 |
$1000 |
$1000 |
$1000 |
$1000 |
Samples of material collected from eight Spotted Tree Frog populations have been examined by allozyme electrophoresis. Results indicate that each population is genetically distinct, suggesting long isolation times and the potential for local adaptation. Further analyses, using various DNA techniques, are proposed to further determine degree of differentiation and the time scale of separation, and to investigate any potential variation within a stream. This work was a major recommendation arising from genetics specialist group in the PHVA workshop. A good understanding of the population genetics of the species is essential if reintroductions or translocations are contemplated.
The first phase of the genetics studies, allozyme electrophoresis, has been largely completed (funded by NRE), and funding is required from ESP to complete the analysis. Additional work utilising more sensitive DNA techniques is required, and can be undertaken largely with existing samples. Funding is required from ESP to establish the DNA testing.
Responsibility: NRE,Consultants
|
Costs |
1998 |
1999 |
2000 |
2001 |
2002 |
|
NRE |
0 |
0 |
0 |
0 |
0 |
|
ESP |
0 |
$4000 |
$20000 |
$20000 |
0 |
|
Total cost |
0 |
$4000 |
$20000 |
$20000 |
0 |
3.6 Action 6 Population viability Analyses
The use of computer programs (eg. VORTEX) to model the long-term viability of species requires detailed information about population demography and dynamics. For the Spotted Tree Frog, some pertinent information has been obtained, however the variability of these data, through time and between populations, is not well understood. Detailed population viability analyses cannot be conducted on each Spotted Tree Frog population until these demographic data are obtained.
A Population and Habitat Viability Assessment (PHVA) workshop on the Spotted Tree Frog was conducted in August 1996. The purpose was to collate and review all data pertaining to the biology, threats and management of the Spotted Tree Frog, as a basis for developing population simulation models, assessing extinction risks, and formulating and assessing different management scenarios. Modelling indicated that management actions should be directed at reducing mortality between egg and metamorph stages and of juveniles. Key threats were identified as predation from fish and sedimentation of stream habitat.
Among the specific research and management recommendations formulated during the workshop, it was seen as essential to conduct further modelling using VORTEX and other models suited to amphibian life histories, with additional time spent on investigating the impact of catastrophic events on population viability, and to repeat the modelling of all scenarios when additional data (as listed below) have been collected.
· collect data on factors affecting egg, tadpole and juvenile survival.
· determine the variation in reproductive output between individual frogs, using genetic techniques.
· investigate the spatial heterogeneity of populations (metapopulation dynamics) using mark-recapture, radio tracking and genetic techniques.
· determine if the Spotted Tree Frog is composed of multiple taxonomic groups, using genetic techniques
· determine the genetic population unit, defined as the areas within which there is random mating, and the genetically viable effective population size for all populations, using genetic techniques.
· continue monitoring of all populations so that population dynamics and environmental variation can be better estimated.
Funding contribution is required from ESP to allow detailed PVA models and assessments to be developed for each population.
Responsibility: NRE, Consultant.
|
Costs |
1998 |
1999 |
2000 |
2001 |
2002 |
|
NRE |
0 |
$5000 |
0 |
0 |
0 |
|
ESP |
0 |
$10000 |
0 |
0 |
0 |
|
Total cost |
0 |
$15000 |
0 |
0 |
0 |
To minimise deleterious effects of predation by introduced fish upon Spotted Tree Frog populations, further liberations of introduced fish in Spotted Tree Frog streams should be prohibited. The following trials should be conducted as a matter of urgency - not only will they provide clear directions for future management, but some may have immediate positive effects on frog populations.
3.7.1 Feasibility Study Fish Exclusion
Feasibility of trout exclusion has been assessed at Bogong Creek, Lightning Creek, Buffalo Creek and Still/White Creeks (Saddlier and Gillespie 1997). Exclusion was shown to be feasible for at least two catchments; Taponga River and Lightning Creek An assessment of the feasibility of excluding introduced trout from other streams or sections of stream habitat supporting Spotted Tree Frog populations will be conducted. This would involve the use of natural barriers or the construction of permanent barriers in streams to eliminate upstream movement of trout, and subsequent eradication of trout above the barrier. Site assessment will consider a range of criteria, including: logistics of eradication by rotenone; amelioration of any effects of this process on other fauna, feasibility of establishing an artificial barrier, if necessary, to eliminate re-invasion of trout from downstream; and probability of re-introduction of trout. The impact of rotenone for eradication purposes on amphibians and invertebrates will also be assessed.
Additional funding is required from ESP to contribute towards extending the feasibility study to other streams.
Responsibility: NRE, NSW NP&WS, Consultant.
|
Costs |
1998 |
1999 |
2000 |
2001 |
2002 |
|
NRE |
0 |
$2000 |
0 |
0 |
0 |
|
ESP |
0 |
$4000 |
0 |
0 |
0 |
|
Total cost |
0 |
$6000 |
0 |
0 |
0 |
Trial eradication and exclusion of trout will be pursued in selected catchments occupied by Spotted Tree Frogs, as determined by feasibility studies (Action 3.7.1). The general strategy for eradication and exclusion of trout is to inject rotenone into the headwaters of a stream, which then kills the fish as it flows downstream. The rotenone is then neutralised with potassium permanganate at a specific point downstream below the section being treated. Rotenone treatment, followed by electrofishing checks, is considered to be the only technique proven to effectively eradicate trout. A barrier is required along the stream, above the point of neutralisation, to stop trout from re-invading from downstream. The barrier can be a natural water fall or a man -made structure which creates a vertical drop in the stream.
An initial trial will be conducted in the Taponga River where detailed frog population monitoring records are available to assess the success of the project. Changes in recruitment and population density will be assessed along monitoring transects within trout exclusion stream reaches, and compared to monitoring transects on reaches outside exclusion zones. If successful, eradication and exclusion will be pursued in other selected catchments. Sites currently considered priorities for trout exclusion are Buffalo Creek, which already has a natural barrier, and Lightning Creek. Other sites will be considered, subject to feasibility assessment (Section 3.7.1).
Costing for the project includes rotenone/electrofishing treatments, construction of an artificial barrier, and subsequent monitoring of both fish and frog populations in treated and control streams. Funding is required from ESP to enable this essential action to proceed.
Responsibility: NRE, NSW NP&WS, Consultant
|
Costs |
1998 |
1999 |
2000 |
2001 |
2002 |
|
NRE |
$20000 |
$10000 |
$10000 |
$10000 |
0 |
|
ESP |
$73000 |
$20000 |
$50000 |
$30000 |
$5000 |
|
Total cost |
$93000 |
$30000 |
$60000 |
$40000 |
$5000 |
3.8 action 8 Disease Investigation
Disease has been implicated as a possible explanation for the decline and disappearance of some amphibians (eg. Bradford 1991; Blaustein et al. 1994; Trenerry et al. 1994; Laurance et al. 1996; Berger et al. 1998). However, in very few studies has the demise of an amphibian population been positively attributed to a pathogenic species (eg. Blaustein et al. 1994). In many cases, the disease hypothesis is largely supported by the discovery of moribund frogs only, with no rigorous assessment to directly link pathogenic species with the demise of amphibian taxa. However, Berger et al. (1998) recently identified a chytrid fungus associated with some declining frog species in Australia and South America which is capable of killing frogs under laboratory conditions. This fungus has been found in several Spotted Tree Frog populations, including the Bogong population prior to the recent decline. In view of the currently unexplained dramatic decline of the Bogong Creek population of Spotted Tree Frogs (Gillespie 1997b), and the potential for disease to be implicated, it is essential to further investigate this possibility. Any dead, moribund or diseased frogs encountered during the research, monitoring and survey have and will be collected and forwarded to a specialist laboratory for analysis, and any possible contribution of disease to the species decline will be determined. Strict procedures, as outlined by the Declining Amphibian Taskforce, will be instigated by field workers to prevent inadvertent transmission of any disease organism.
Funding is required from ESP to augment the collection of specimens, and to enable these laboratory investigations to be undertaken. They will complement, rather than duplicate, similar investigations with other frog taxa, and should be conducted in concert with the broader investigations.
Responsibility: NRE,Consultants
|
Costs |
1998 |
1999 |
2000 |
2001 |
2002 |
|
NRE |
0 |
0 |
0 |
0 |
0 |
|
ESP |
$2500 |
$2500 |
0 |
0 |
0 |
|
Total cost |
$2500 |
$2500 |
0 |
0 |
0 |
3.9 Action 9 Captive Husbandry
The role of captive husbandry in Spotted Tree Frog conservation may become increasingly important if the factors responsible for the decline in the Spotted Tree Frog populations continue to operate. Captive group(s) of frogs may be invaluable for studies on reproductive biology, as a source of animals for genetic studies, as a potential reservoir and source of animals for reintroductions, and as a public education resource. They may also be of great benefit in providing for short-term enhancement of recruitment to wild populations, where particular life stages (eg. eggs) may be collected from the field, raised in captivity through the stages during which most mortality in the field would occur, and then released. The techniques required to maintain captive groups must be determined before any larger scale population enhancements or translocations are attempted. Any collection of individuals must not compromise wild populations.
A captive management strategy will be developed by NRE to identify objectives and priorities of the captive management program, and provide guidelines and a methodological framework for achieving these.
Husbandry techniques will be developed and implemented by a suitably experienced consultant. To preclude the possibility of exposure of frogs to exotic pathogens during the husbandry trials, and to prevent any subsequent release of contaminated frogs at completion, strict measures will be put in place to ensure that raising of eggs, larvae and frogs are undertaken in isolated and sterile conditions. Frogs will only be released to the field if it can be shown there is no risk of disease introduction, and only if the release is undertaken as part of a planned enhancement or reintroduction program.
Funding is required from ESP to establish a suitable husbandry facility and to provide for ongoing maintenance of captive individuals during the husbandry trials. Husbandry programs are currently in place for two other endangered south-eastern Australian frog species; the Baw Baw Frog (Philoria frosti) and the Corroboree Frog (Pseudophryne corroboree). The establishment of a combined facility for all frog husbandry programs is highly desirable and is likely to result in considerable overall cost savings. However, the ecological requirements of the Spotted Tree Frog are completely different from those of the above species, which are both alpine bog specialists. Consequently the husbandry of Spotted Tree Frogs will require markedly different techniques and equipment from those developed for these species. Nevertheless the establishment of a combined facility will minimise duplication of effort and enable cost savings where possible. The husbandry techniques developed by this facility will also be transferable to other eastern Australian riverine amphibian species which may require similar recovery actions in the future. The costs indicated here are estimated to enable establishment and maintenance of a husbandry program for the Spotted Tree Frog, building upon existing facilities.
The Amphibian Research Centre has already carried out husbandry work upon the Spotted Tree Frog at its own expense for the past two years, and will continue to cover a significant component of the on-going costs.
Initially, husbandry will continue on a small scale to assess the effectiveness of techniques currently being trialed. If successful the program will be expanded to support re-introduction and enhancement programs (see Action 3.10)
Responsibility: NRE, Consultants
|
Costs |
1998 |
1999 |
2000 |
2001 |
2002 |
|
NRE |
$10000 |
0 |
0 |
0 |
0 |
|
Consultant |
$20000 |
$10000 |
$10000 |
$10000 |
$10000 |
|
ESP |
$10000 |
$30000 |
$10000 |
$10000 |
$10000 |
|
Total cost |
$40000 |
$40000 |
$20000 |
$20000 |
$20000 |
3.10 Action 10 RE-INTRODUCTION/Translocation/enhancement
To improve recruitment at existing threatened populations, or to reintroduce populations to sites where the species is now extinct, translocation programs (with or without a captive component) or enhancement programs (involving captive maintenance for some period; see Action 3.9 above) will be attempted. Experimental trials are required to determine the feasibility, methodology and benefits of such exercises.
The possibility of reintroducing a population of Spotted Tree Frogs to Buffalo Creek, where the species is now thought to be extinct, will be examined. This will be contemplated only if the factors responsible for extinction are understood and can be managed (eg. by excluding introduced trout; see Actions 3.7.1 and 3.7.2), and if all genetic considerations can be satisfied. Rigorous monitoring of any such introduced population is essential and will be undertaken.
A re-introduction strategy will be developed by NRE, to identify objectives and priorities for re-introductions or translocations, and appropriate guidelines and methods for implementation and monitoring.
Funding is required from ESP to enable this trial at Buffalo Creek to proceed, and for subsequent monitoring of the population.
Responsibility: NRE, NSW NP&WS, Consultants
|
Costs |
1998 |
1999 |
2000 |
2001 |
2002 |
|
NRE |
0 |
$5000 |
$5000 |
$2000 |
$2000 |
|
ESP |
0 |
$20000 |
$20000 |
$4000 |
$4000 |
|
Total cost |
0 |
$25000 |
$25000 |
$6000 |
$6000 |
3.11 Action 11 Habitat Management
Many management activities which will enhance Spotted Tree Frog populations and their habitat have been identified and will be implemented, as below. The costing for many of these activities is currently uncertain, however some may be implemented within existing budgets of management authorities.
O'Shaughnessy (1995) identified existing roads and stream crossings, both their initial construction and subsequent poor maintenance, as a major source of sediment into Spotted Tree Frog steams. Remedial measures are urgently required. The issue is potentially of some magnitude and could require significant resources to rehabilitate or close problem roads. The first step in this process is to assess all roads in Spotted Tree Frog catchments for their condition and their contribution to sediment input to streams, and to allocate priorities for remedial actions.
Funding has been made available within NRE and from the RFA process to undertake this initial assessment, which is currently under way. While road maintenance and repair are ongoing costs to NRE, many roads urgently require substantial funding input to raise them to acceptable standards. NRE has committed some funds to rehabilitation in the Taponga catchment, as a matter of priority for Spotted Tree Frog conservation. Further funds (yet to be determined) will be required within NRE to continue the overall rehabilitation program, with priority being given to Spotted Tree Frog catchments.
NSW NPWS has negotiated with the SMA to rehabilitate the Bourke's Gorge Road to reduce sediment input into Bogong Creek. Guidelines will be produced by NSW NPWS in consultation with the SMA for the future reconstruction and up-grading of the Bourke's Gorge Road bridge over Bogong Creek to minimise disturbance to the stream bed and banks. The new bridge will further reduce sediment input from the road in the long term. The feasibility of rehabilitation of the large spoil dump down stream of Bourke's Gorge will also be investigated in conjunction with the SMA.
Responsibility: NRE, NSW NPWS
|
Costs |
1998 |
1999 |
2000 |
2001 |
2002 |
|
NRE |
$72000 |
? |
? |
? |
? |
|
NSW NPWS |
$2500 |
$2500 |
0 |
0 |
|
|
ESP |
0 |
0 |
0 |
0 |
0 |
|
Total costs |
$72000 |
? |
? |
? |
? |
Prescriptions for the construction of new roads and stream crossings in Spotted Tree Frog catchments will be formulated according to the guidelines of O'Shaughnessy (1995), incorporated into all relevant management documents, and implemented.
Responsibility: NRE
|
Costs |
1998 |
1999 |
2000 |
2001 |
2002 |
|
NRE |
$2000 |
$2000 |
$2000 |
$2000 |
$2000 |
|
NSW NPWS |
$500 |
$500 |
$500 |
$500 |
$500 |
|
ESP |
0 |
0 |
0 |
0 |
0 |
|
Total costs |
$2500 |
$2500 |
$2500 |
$2500 |
$2500 |
3.11.3 Timber Harvesting Prescriptions
Prescriptions for the conduct of timber harvesting operations in Spotted Tree Frog catchments will be formulated according to the guidelines of O'Shaughnessy (1995), incorporated into all relevant management documents, and implemented.
Responsibility: NRE
|
Costs |
1998 |
1999 |
2000 |
2001 |
2002 |
|
NRE |
$2000 |
$1000 |
$1000 |
$1000 |
$1000 |
|
ESP |
0 |
0 |
0 |
0 |
0 |
|
Total costs |
$2000 |
$1000 |
$1000 |
$1000 |
$1000 |
To prevent changes in the habitat of the Spotted Tree Frog or changes to water quality in STF streams: Do not permit prescribed fire in the Spotted Tree Frog habitat, and aim to exclude all fire from this area. Fuel reduction burning to be excluded from all catchments upstream of Spotted Tree Frog habitat where possible. Fire management strategy to be developed for each catchment, including provision for treatment of wildfire such that minimal disturbance to Spotted Tree Frog habitat is maintained; to be included in area fire management plans.
Responsibility: NRE, NSW NP&WS
|
Costs |
1998 |
1999 |
2000 |
2001 |
2002 |
|
NRE |
$1000 |
$1000 |
0 |
0 |
0 |
|
NSW NPWS |
$1000 |
$1000 |
0 |
0 |
0 |
|
ESP |
0 |
0 |
0 |
0 |
0 |
|
Total costs |
$2000 |
$2000 |
0 |
0 |
0 |
Spraying with herbicides may be very risky in areas known to support frogs. Where weed control is required for land management purposes, hand weeding/slashing should be implemented in preference to spraying. In areas of heavy infestations, consider spraying only as a last resort after consideration of application method, knowledge of toxicity, and best time to spray to minimise impact upon frogs. Monitor effects. Consider hand weeding/slashing and/or limited spraying of Blackberry (Rubus spp.) with biodegradable chemicals in catchments where the weed is controllable and may be affecting frog habitat.
Responsibility: NRE, SMA, NSW NP&WS
|
Costs |
1998 |
1999 |
2000 |
2001 |
2002 |
|
NRE |
$2000 |
$1000 |
$1000 |
$1000 |
$1000 |
|
NSW NPWS |
$1000 |
$1000 |
$1000 |
$1000 |
$1000 |
|
ESP |
0 |
0 |
0 |
0 |
0 |
|
Total costs |
$3000 |
$2000 |
$2000 |
$2000 |
$2000 |
To prevent disturbances to Spotted Tree Frog habitat, and to prevent changes in water quality, investigate the impacts of cattle grazing in Spotted Tree Frog catchments, with regard to the potential deterioration of riparian habitat or changes to water quality in streams. If grazing is shown to be affecting Spotted Tree Frog populations or habitat, instigate measures to ameliorate the disturbance, such as (for example) preventing cattle access to streams, by restriction of licences, or by imposition of appropriate licence conditions, such as requirement for electric fencing.
Responsibility: NRE
|
Costs |
1998 |
1999 |
2000 |
2001 |
2002 |
|
NRE |
$2000 |
$1000 |
$1000 |
$1000 |
$1000 |
|
ESP |
0 |
0 |
0 |
0 |
0 |
|
Total costs |
$2000 |
$1000 |
$1000 |
$1000 |
$1000 |
The provision of information to visitors about the ecology of sensitive flora and fauna, and their protection, is an important component of the conservation and protection of Spotted Tree Frog habitat. Interpretative signs detailing information on sensitive communities and species, including the Spotted Tree Frog, will be constructed and made available to visitors.
Some camp sites have been established within sensitive vegetation communities, including Spotted Tree Frog habitat. To prevent human disturbance to frog behaviour and deterioration of frog habitat, do not increase access to streams, and close access to frog habitat in some areas, as required to exclude disturbance. Actively manage camping areas near frog habitat to minimise recreational impacts or, where feasible, relocate these camping areas away from Spotted Tree Frog catchments to exclude disturbance.. The recovery of existing camp sites, and incidence of new camp sites, will be monitored during frog population surveys to assess the potential impact on the habitat and biology of the Spotted Tree Frog.
Restrict road use to a minimum in catchments, particularly in wet weather, when sediment risk would be greatest. Continued monitoring of the impact of recreational activities on the environment is necessary to provide feedback on the effectiveness of management actions
Responsibility: NRE
|
Costs |
1998 |
1999 |
2000 |
2001 |
2002 |
|
NRE |
$5000 |
$5000 |
$2000 |
$2000 |
$2000 |
|
ESP |
0 |
0 |
0 |
0 |
0 |
|
Total cost |
$5000 |
$5000 |
$2000 |
$2000 |
$2000 |
To prevent disturbances to Spotted Tree Frog habitat, and to prevent changes in water quality (particularly sediment levels) and quantity in streams, strictly enforce ban on eductor dredging at all Spotted Tree Frog streams. Recommend exclusion of exploration and mining from areas in all catchments where these activities may effect Spotted Tree Frog habitat, and develop suitable management prescriptions to prevent such disturbances. In Victoria, the Mines Act requires EES investigation prior to activities in Special Protection Zones in state forest areas - a similar requirement should be instigated for all Spotted Tree Frog catchments.
Responsibility: NRE
|
Costs |
1998 |
1999 |
2000 |
2001 |
2002 |
|
NRE |
$1000 |
$1000 |
$1000 |
$1000 |
$1000 |
|
ESP |
0 |
0 |
0 |
0 |
0 |
|
Total costs |
$1000 |
$1000 |
$1000 |
$1000 |
$1000 |
To prevent changes in flow regimes which may result in reduced breeding opportunities for Spotted Tree Frogs or reduced survivorship of tadpoles, liaise with the water management authorities responsible for each catchment to ensure that any potential stream works (eg. diversions, impoundments, etc) do not impinge upon Spotted Tree Frog habitat, do not cause changes in water quality, and do not substantially effect current flow regimes. Ensure that maintenance activities (eg. de-silting of water storages) do not affect Spotted Tree Frog habitat and do not cause changes in water quality.
In conjunction with the Snowy Mountains Authority, coordinate annual water releases so as to maximise benefits for the frog population on Bogong Creek. Examine the impact of five-year maintenance flushing of the by the Snowy Mountains Authority. Improve drainage of Bourke's Road to ameliorate run-off into the stream. Restrict further activities which may encroach on the stream environment, eg. new roads, stream crossings, spoil areas. Examine the feasibility of rehabilitation of riparian habitats near Bourke's Road crossing and the tunnel spoil area.
Responsibility: NRE, NSW NP&WS
|
Costs |
1998 |
1999 |
2000 |
2001 |
2002 |
|
NRE |
$1000 |
$1000 |
$1000 |
$1000 |
$1000 |
|
NSW NPWS |
$5000 |
$5000 |
$1000 |
$1000 |
$1000 |
|
ESP |
0 |
0 |
0 |
0 |
0 |
|
Total costs |
$6000 |
$6000 |
$2000 |
$2000 |
$2000 |
3.12 Action 12 Monitoring of Adherence to Management
Prescriptions
Any adverse effects of imposed disturbances upon Spotted Tree Frog populations need to be rapidly identified. To ensure that this occurs, on-site monitoring audits of these activities will be conducted at least twice yearly, and contingency plans developed to quickly remedy any threatening situation.
All new roads and coupes in Spotted Tree Frog catchments will be monitored, both during and after construction/utilisation, for compliance with management prescriptions.
Monitor the effectiveness of the prescriptions in preventing any changes to stream parameters (particularly sediment in all catchments in which disturbances are imposed, both at the time of the disturbance and during peak storm events subsequently, to enable cessation of activities and/or remedial actions to be instigated should breaches or threats to the frogs be detected.
The management prescriptions are to be reviewed and revised as necessary for all catchments.
Responsibility: NRE, NSW NP&WS
|
Costs |
1998 |
1999 |
2000 |
2001 |
2002 |
|
NRE |
$2000 |
$2000 |
$2000 |
$2000 |
$2000 |
|
NSW NPWS |
$1000 |
$1000 |
$1000 |
$1000 |
$1000 |
|
ESP |
0 |
0 |
0 |
0 |
0 |
|
Total cost |
$2000 |
$2000 |
$2000 |
$2000 |
$2000 |
Contingency plans will be developed to enable immediate remedial action to be undertaken should any breach of management prescriptions be detected, or should adverse effects of any activities (even those adhering to prescriptions) become apparent.
Should further populations of the Spotted Tree Frog be discovered, then the management prescriptions developed for known populations will apply, until such time as 25 populations are secure, after which a reappraisal of the conservation program will be required.
Responsibility: NRE, NSW NP&WS
|
Costs |
1998 |
1999 |
2000 |
2001 |
2002 |
|
NRE |
$2000 |
$2000 |
0 |
0 |
0 |
|
NSW NPWS |
$2000 |
$2000 |
0 |
0 |
0 |
|
ESP |
0 |
0 |
0 |
0 |
0 |
|
Total cost |
$4000 |
$4000 |
0 |
0 |
0 |
3.13 Action 13 Community Involvement
Continue previous extension and media activities, targeted at education of anglers, bushwalkers, campers and the public, such that their acceptance of any restriction of activities resulting from Spotted Tree Frog management will be enhanced. Continue training of NRE personnel in identification and monitoring, to facilitate long-term monitoring of frog populations by Area personnel. Continue liaison with conservation and specialist herpetological groups and seek their continued support.
Revise and reprint the identification brochure (discontinue previous reporting sheet as no records resulted). Include the brochure within a broader education 'kit' containing fact sheets on various aspects of the frogs biology and conservation management. Include project ideas for students. Distribute widely through conservation, education and angling networks.
Seek support from conservation and herpetological groups for the formation of a 'friends group' for assistance with media liaison, broad distribution of information, and some 'on-ground' works (see 3.13.2).
Target peak angling bodies and conservation groups for distribution of information, and seek their support for and assistance with the recovery program.
Erect interpretive signs or similar material near frog habitat areas which have high visitor usage, to explain and enlist support for any restriction of recreational activities. Enforce any such restrictions.
Funding is required from ESP to assist with preparation and publication of interpretive material.
Responsibility: NRE, Friends Group
|
Costs |
1998 |
1999 |
2000 |
2001 |
2002 |
|
NRE |
$2000 |
$1000 |
$1000 |
$1000 |
$1000 |
|
NGO |
$2000 |
$2000 |
$1000 |
$1000 |
$1000 |
|
ESP |
$2000 |
$1000 |
0 |
0 |
0 |
|
Total cost |
$6000 |
$4000 |
$2000 |
$2000 |
$2000 |
A friends group or special interest group within an herpetological organisation (or some amalgam of the two), when formed, could assist conservation of the Spotted Tree Frog in a number of key areas, while providing a valuable educational experience for group members.
Such assistance could include:
The funding proposed for this action is largely for costs associated with field work for the on-ground management works.
Responsibility: NRE, Friends Group
|
Costs |
1998 |
1999 |
2000 |
2001 |
2002 |
|
NRE |
$2000 |
$2000 |
$2000 |
$2000 |
$2000 |
|
NGO |
$2000 |
$2000 |
$2000 |
$2000 |
$2000 |
|
ESP |
0 |
0 |
0 |
0 |
0 |
|
Total cost |
$4000 |
$4000 |
$4000 |
$4000 |
$4000 |
3.14 Action 14 Management of Recovery Program
3.14.1 Operation of Recovery Team
A Recovery Team to advise on issues arising within the Spotted Tree Frog research program has been operating for several years. With the status of the species and its threats now established, and many aspects of its biology understood, requirement for an intensive recovery effort recognised, and some of funds and resources committed from organisations, recovery actions can be implemented to attempt to prevent extinction of the species. The Recovery Team includes participants with a range of required skills, particularly in frog ecology, population genetics, captive breeding, land management and utilisation, and project management. The Recovery Team will be responsible for implementing the Recovery Plan, including the detailed planning required for the program, such as the identification of actions, targets, responsibilities and time-lines for their completion. The Recovery Team will also monitor and assess implementation of the Recovery Plan, and will need to address administrative issues relating to the recovery effort, including the issue and management of contracts for components of the program, and obtaining relevant permits to enable work to proceed. The major cost for management of the recovery program (salaries for project planners) will be met by NRE. Other participating agencies will be responsible for their own costs.
Responsibility: NRE, NSW NPWS, ESP, Other recovery team members
|
Costs |
1998 |
1999 |
2000 |
2001 |
2002 |
|
NRE |
$8000 |
$8000 |
$8000 |
$8000 |
$8000 |
|
ESP |
0 |
0 |
0 |
0 |
0 |
|
Total cost |
$8000 |
$8000 |
$8000 |
$8000 |
$8000 |
3.14.2 Recovery Program Evaluation and Review
Regular review and evaluation of implementation of the recovery effort is essential, especially in a program such as this where there is a high degree of uncertainty. Reviews and evaluations are required to determine if objectives are being met, to rapidly identify and solve problems, and to revise objectives. Regular informal reviews should occur at recovery team meetings, and a major formal review and evaluation (possibly utilising an external facilitator) held annually. NRE will meet the cost of holding the annual review. Participating agencies will be responsible for their own costs.
Responsibility: NRE
|
Costs |
1998 |
1999 |
2000 |
2001 |
2002 |
|
NRE |
$3000 |
$3000 |
$3000 |
$3000 |
$3000 |
|
ESP |
0 |
0 |
0 |
0 |
0 |
|
Total cost |
$3000 |
$3000 |
$3000 |
$3000 |
$3000 |
3.14.3 Spotted Tree Frog Action Statement
A Victorian Action Statement, under the Flora and Fauna Guarantee Act 1988, will be published for the Spotted Tree Frog in 1998, and is due for review and update in 2002. Investigate, define and declare the critical habitat of the Spotted Tree Frog under the FFG Act 1988.
Responsibility: NRE
|
Costs |
1998 |
1999 |
2000 |
2001 |
2002 |
|
NRE |
$5000 |
0 |
0 |
0 |
0 |
|
ESP |
0 |
0 |
0 |
0 |
0 |
|
Total cost |
$5000 |
0 |
0 |
0 |
0 |
3.14.4 Preparation of the Spotted Tree Frog Recovery Plan
The production of this Recovery Plan will be completed by the Department of Natural Resources and Environment.
Responsibility: NRE
|
Costs |
1998 |
1999 |
2000 |
2001 |
2002 |
|
NRE |
$5000 |
0 |
0 |
0 |
0 |
|
ESP |
0 |
0 |
0 |
0 |
0 |
|
Total cost |
$5000 |
0 |
0 |
0 |
0 |
|
Task # |
Task Description |
Priority |
Feasibility |
Responsible Party |
Cost Estimates ($000s/financial year ) |
||||||||||||
|
1998 |
1999 |
2000 |
2001 |
2002 |
Total |
||||||||||||
|
3.1 |
Long-term Monitoring |
1 |
100 |
NRE, Consultant |
a |
3 |
3 |
3 |
3 |
3 |
15 |
||||||
|
NSW NPWS |
b |
1 |
1 |
1 |
1 |
1 |
5 |
||||||||||
|
c |
1 |
1 |
1 |
1 |
1 |
5 |
|||||||||||
|
e |
5 |
5 |
5 |
5 |
5 |
25 |
|||||||||||
|
3.2 |
Population Monitoring |
1 |
100 |
Consultant |
a |
10.5 |
10.5 |
10.5 |
10.5 |
10.5 |
52.5 |
||||||
|
NSW NPWS |
b |
19.5 |
19.5 |
19.5 |
19.5 |
19.5 |
97.5 |
||||||||||
|
e |
30 |
30 |
30 |
30 |
30 |
150 |
|||||||||||
|
3.3 |
Further Survey |
1 |
100 |
Consultant |
a |
3 |
- |
- |
- |
- |
3 |
||||||
|
(i) known site limits |
b |
- |
3 |
- |
- |
- |
3 |
||||||||||
|
(ii) new streams limits |
c |
2 |
2 |
- |
- |
- |
4 |
||||||||||
|
e |
5 |
5 |
- |
- |
- |
10 |
|||||||||||
|
3.4 |
Skeletochronology |
1 |
100 |
Consultant |
b |
4 |
1 |
1 |
1 |
1 |
8 |
||||||
|
e |
4 |
1 |
1 |
1 |
1 |
8 |
|||||||||||
|
3.5 |
Genetic Studies |
2 |
100 |
Consultant |
b |
- |
4 |
20 |
20 |
- |
44 |
||||||
|
e |
- |
4 |
20 |
20 |
- |
44 |
|||||||||||
|
3.6 |
PVA Analyses |
1 |
90 |
NRE, Consultant |
a |
- |
5 |
- |
- |
- |
5 |
||||||
|
b |
- |
10 \520 |
- |
- |
- |
10 |
|||||||||||
|
e |
- |
15 |
- |
- |
- |
15 |
|||||||||||
|
3.7 |
Fish Studies |
||||||||||||||||
|
3.7.1 |
Feasibility study fish exclusion |
1 |
100 |
NRE, Consultant, |
a |
- |
2 |
- |
- |
- |
2 |
||||||
|
b |
- |
4 |
- |
- |
- |
4 |
|||||||||||
|
e |
6 |
- |
- |
- |
6 |
||||||||||||
|
3.7.2 |
Trial fish exclusion |
1 |
90 |
Consultant, NRE |
a |
20 |
10 |
10 |
10 |
- |
40 |
||||||
|
(costing dependent upon 3.7.1) |
b |
73 |
20 |
50 |
30 |
5 |
148 |
||||||||||
|
e |
93 |
30 |
60 |
40 |
5 |
228 |
|||||||||||
|
3.8 |
Disease Investigation |
1 |
70 |
Consultant |
b |
2.5 |
2.5 |
- |
- |
- |
5 |
||||||
|
e |
2.5 |
2.5 |
- |
- |
- |
5 |
|||||||||||
|
3.9 |
Captive Husbandry |
2 |
70 |
Consultant |
a |
10 |
- |
- |
- |
- |
10 |
||||||
|
b |
10 |
30 |
10 |
10 |
10 |
70 |
|||||||||||
|
d |
20 |
10 |
10 |
10 |
10 |
60 |
|||||||||||
|
e |
40 |
40 |
20 |
20 |
20 |
140 |
|||||||||||
|
3.10 |
Re-introduction/ |
2 |
80 |
Consultant, NRE |
a |
- |
5 |
5 |
2 |
2 |
14 |
||||||
|
b |
- |
20 |
20 |
4 |
4 |
48 |
|||||||||||
|
e |
- |
25 |
25 |
6 |
6 |
62 |
|||||||||||
a:NRE contribution; b:ESP funds required; c:NSW NP&WS contribution; d: other; e: Total Cost of Action
Priorities: 1. critical to prevent extinction. 2. Prevents negative impact short of extinction. 3. Desirable as integral part of recovery program.
|
Task # |
Task Description |
Priority |
Feasibility |
Responsible Party |
Cost Estimates ($000s/year) |
||||||||||||
|
1998 |
1999 |
2000 |
2001 |
2002 |
Total |
||||||||||||
|
3.11 |
Habitat Management |
||||||||||||||||
|
3.11.1 |
Roading rehabilitation |
1 |
90 |
NRE, NP&WS Consultant |
a |
50 |
? |
? |
? |
? |
50 |
||||||
|
c |
2.5 |
2.5 |
- |
- |
- |
5 |
|||||||||||
|
e |
52.5 |
2.5 |
? |
? |
? |
55 |
|||||||||||
|
3.11.2 |
Roading prescriptions |
1 |
100 |
NRE, NP&WS |
a |
2 |
2 |
2 |
2 |
2 |
10 |
||||||
|
c |
0.5 |
0.5 |
0.5 |
0.5 |
0.5 |
2.5 |
|||||||||||
|
e |
2.5 |
2.5 |
2.5 |
2.5 |
2.5 |
12.5 |
|||||||||||
|
3.11.3 |
Timber harvesting prescriptions |
1 |
100 |
NRE |
a |
2 |
1 |
1 |
1 |
1 |
6 |
||||||
|
e |
2 |
1 |
1 |
1 |
1 |
6 |
|||||||||||
|
3.11.4 |
Fire Management |
1 |
100 |
NRE, NSW NP&WS |
a |
1 |
1 |
- |
- |
- |
2 |
||||||
|
c |
1 |
1 |
2 |
||||||||||||||
|
e |
2 |
2 |
- |
- |
- |
4 |
|||||||||||
|
3.11.5 |
Weed Control |
2 |
80 |
NRE, NSW NP&WS |
a |
2 |
1 |
1 |
1 |
1 |
6 |
||||||
|
c |
1 |
1 |
1 |
1 |
1 |
5 |
|||||||||||
|
e |
3 |
2 |
2 |
2 |
2 |
11 |
|||||||||||
|
3.11.6 |
Grazing Management |
3 |
80 |
NRE |
a |
2 |
1 |
1 |
1 |
1 |
6 |
||||||
|
e |
2 |
1 |
1 |
1 |
1 |
6 |
|||||||||||
|
3.11.7 |
Recreation Management |
1 |
90 |
NRE |
a |
5 |
5 |
2 |
2 |
2 |
16 |
||||||
|
e |
5 |
5 |
2 |
2 |
2 |
16 |
|||||||||||
|
3.11.8 |
Mining Management |
2 |
90 |
NRE |
a |
1 |
1 |
1 |
1 |
1 |
5 |
||||||
|
e |
1 |
1 |
1 |
1 |
1 |
5 |
|||||||||||
|
3.11.9 |
Water Management |
1 |
90 |
NRE, NPWS |
a |
1 |
1 |
1 |
1 |
1 |
5 |
||||||
|
c |
5 |
5 |
1 |
1 |
1 |
13 |
|||||||||||
|
e |
6 |
6 |
2 |
2 |
2 |
18 |
|||||||||||
|
3.12 |
Monitoring prescriptions |
||||||||||||||||
|
3.12.1 |
Monitoring |
1 |
100 |
NRE, NPWS |
a |
2 |
2 |
2 |
2 |
2 |
10 |
||||||
|
c |
1 |
1 |
1 |
1 |
1 |
5 |
|||||||||||
|
e |
3 |
3 |
3 |
3 |
3 |
15 |
|||||||||||
|
3.12.2 |
Contingency Planning |
1 |
100 |
NRE, NPWS |
a |
2 |
2 |
- |
- |
- |
4 |
||||||
|
c |
2 |
2 |
- |
- |
- |
4 |
|||||||||||
|
e |
4 |
4 |
- |
- |
- |
8 |
|||||||||||
|
3.13 |
Community Involvement |
||||||||||||||||
|
3.13.1 |
Educational materials, brochure |
3 |
90 |
NRE, NSW NPWS, NGO |
a |
2 |
1 |
1 |
1 |
1 |
6 |
||||||
|
b |
2 |
1 |
- |
- |
- |
3 |
|||||||||||
|
d |
2 |
2 |
1 |
1 |
1 |
7 |
|||||||||||
|
e |
6 |
4 |
2 |
2 |
2 |
16 |
|||||||||||
|
3.13.2 |
Friends group, habitat mgt.. |
3 |
90 |
NRE, NSW NPWS, NGO |
a |
2 |
2 |
2 |
2 |
2 |
10 |
||||||
|
on site displays |
d |
2 |
2 |
2 |
2 |
2 |
10 |
||||||||||
|
e |
4 |
4 |
4 |
4 |
4 |
20 |
|||||||||||
a:NRE contribution; b:ESP funds required; c: NSW NP&WS contribution; d: other; e: Total Cost of Action
|
Task # |
Task Description |
Priority |
Feasibility |
Responsible Party |
Cost Estimates ($000s/year) |
||||||||||||
|
1998 |
1999 |
2000 |
2001 |
2002 |
Total |
||||||||||||
|
3.14 |
Management of Recovery |
||||||||||||||||
|
3.14.1 |
Operation of Recovery Team |
1 |
100 |
NRE |
a |
8 |
8 |
8 |
8 |
8 |
40 |
||||||
|
e |
8 |
8 |
8 |
8 |
8 |
40 |
|||||||||||
|
3.14.2 |
Recovery Evaluation & Review |
1 |
100 |
NRE, NSW NPWS, ESP |
a |
3 |
3 |
3 |
3 |
3 |
15 |
||||||
|
e |
3 |
3 |
3 |
3 |
3 |
15 |
|||||||||||
|
3.14.3 |
STF Action Statement |
1 |
100 |
NRE |
a |
5 |
- |
- |
- |
- |
5 |
||||||
|
e |
5 |
- |
- |
- |
- |
5 |
|||||||||||
|
3.14.4 |
STF recovery Plan |
1 |
100 |
NRE |
a |
5 |
5 |
||||||||||
|
e |
5 |
5 |
|||||||||||||||
|
Total ($000s) |
293.5 |
212.5 |
192.5 |
153.5 |
98.5 |
950.5 |
|||||||||||
a:NRE contribution; b:ESP funds required; c: NSW NP&WS contribution; d: other; e: Total Cost of Action
Special thanks must go to all members of the Spotted Tree Frog Recovery Team for their input into the preparation and refinement of the Recovery Program. Kim Lowe, NRE, Graeme Enders, NSW NPWS and the Biodiversity Group, Environment Australia provided additional comment on the manuscript. The Department of Natural Resources and Environment provided funds to support the preparation of this Recovery Plan.
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Disclaimer:
The views expressed in this report are those of the authors and do not necessarily reflect those of the Biodiversity Group of Environment Australia, Canberra.
Publication reference and availability details:
Robertson, P. and Gillespie, G. (1998). Recovery Plan for the Spotted Tree Frog (Litoria spenceri). Report to Environment Australia, Canberra.