Recovery Plan for the Pedder, Swan, Clarence, Swamp and Saddled Galaxias

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David Crook and Andrew Sanger
Inland Fisheries Commission, 1997
Revised 1999

Contents


Foreword

The following recovery plan addresses the five species of endemic Tasmanian galaxiids listed in the schedules of the Endangered Species Protection Act 1992. The merger of recovery efforts for these species under the direction of a single project officer, as outlined in the recovery plan, will facilitate logistic, managerial and financial efficiencies that would not be possible if the species were considered separately. The 'Recovery Plan for the Pedder, Swan, Clarence, Swamp and Saddled Galaxias' outlines an up to date series of management recommendations and actions and is intended to replace the previous recovery plans and funding proposals for the Pedder and Swan galaxias.

Conservation status

The conservation status generally referred to in this recovery plan is the status applied by the Australian Society for Fish Biology (ASFB). The International Union for the Conservation of Nature (IUCN) criteria are also referred to although the suitability of these criteria has not been widely tested upon Australian fish. The IUCN criteria are currently being assessed by the ASFB and the criteria referred to in this recovery plan will be altered if necessary once this issue has been resolved.

Population viability analysis

Population viability analysis (PVA) has not been included in the recovery plan as it was considered that the costs of collecting sufficient data for a meaningful analysis would far outweigh the benefits. A PVA conducted for a similar species (Galaxias fuscus) by Raadik (1995) has been used as a guide for the setting of recovery criteria for the five species in this recovery plan.

Land tenure

None of the fish dealt with in this plan occur on Commonwealth lands. The species variously occur on private property, National Parks, Conservation Areas, State Forests, Forest Reserves, Land Recreation Areas and land managed by the Hydro-Electric Corporation.

Tasmanian Galaxiids Recovery Team

In April 1994, two recovery teams were formed to guide the Pedder galaxias and Swan galaxias recovery plans. In May 1996, it was decided to merge the two teams to form the Tasmanian Galaxiids Recovery Team to guide conservation efforts for all threatened galaxiid fishes in Tasmania. Current membership of the Tasmanian Galaxiid Recovery Team includes representatives of Environment Australia, the Inland Fisheries Commission, the Parks and Wildlife Service, Forestry Tasmania, the Hydro-Electric Corporation, the World Wide Fund for Nature, the Freshwater Anglers Council of Tasmania, the Tasmanian Farmers and Graziers Association and the University of Tasmania.

Glossary of abbreviations

  • IFC Inland Fisheries Commission
  • EA Environment Australia
  • ESP Endangered Species Program
  • HEC Hydro-Electric Corporation
  • PWS Tasmanian Parks and Wildlife Service
  • ASFB Australian Society for Fish Biology
  • IUCN International Union for the Conservation of Nature

SUMMARY

Current species status (Endangered Species Protection Act 1992):

Pedder galaxias (Galaxias pedderensis): Endangered

Swan galaxias (Galaxias fontanus): Endangered

Clarence galaxias (Galaxias johnstoni): Endangered

Swamp galaxias (Galaxias parvus): Vulnerable

Saddled galaxias (Galaxias tanycephalus): Vulnerable

The endemic freshwater fish fauna of Tasmania consists largely of fishes of the family Galaxiidae. Galaxiids are relatively small fish and are preyed upon heavily by introduced fish species. A characteristic of these fish is the severely restricted natural range of each species. Restricted distributions and susceptibility to predation make Tasmania's endemic galaxiids unusually prone to major population declines. This is highlighted by the near extinction of the formerly abundant Pedder galaxias within a ten year span.

Habitat requirements and limiting factors:

The five galaxiid species included in these recovery actions inhabit a variety of freshwater habitats including streams, swamps and lakes. The specificity of habitat requirements are generally unknown for each species as reproductive and general behaviours have not yet been detailed. All five species are known to be preyed upon by introduced fish. Predation by and/or competetion with introduced species is the major threatening process for all five species.

Recovery objectives:

The overall objective of these recovery actions is to secure existing populations and improve the conservation status of each species. Specific objectives are outlined for each species in the recovery plan.

Recovery will be assessed against the following basic criteria:

  • 1. Objectives regarding the number and size of populations for each species should be achieved (see individual recovery criteria).
  • 2. No further population declines or reductions in range in any of the species should occur in the next five years.
  • 3. Detailed protocols for captive breeding of threatened galaxiids should be produced.

Actions needed:

1. Recovery co-ordination 4. Captive breeding trials
2. Monitor natural populations 5. Habitat management
3. Establish translocated populations 6. Public information and education

Cost of recovery ($ 000s/year):

Total funds required.

Action

1

2

3

4

5

6

Total

Year

T

T

T

T

T

T

T

1

73.0

18.0

87.0

22.0

-

13.9

213.9

2

75.5

16.0

20.0

9.0

-

0.6

121.1

3

79.5

15.0

19.0

9.0

-

0.6

123.1

4

82.0

15.0

19.0

9.0

-

0.6

125.6

5

84.0

15.0

19.0

9.0

-

0.6

127.6

Total

394.0

79.0

164.0

58.0

-

16.3

711.3

Biodiversity benefits:

Development of detailed captive breeding protocols will provide information directly applicable to the captive breeding of other threatened freshwater fish. The listing of critical habitat under the Tasmanian Threatened Species Protection Act 1995 will provide legislative protection of aquatic and terrestrial habitats occupied by other endemic species within the ranges of the five threatened galaxiids (eg. Arthurs paragalaxias Paragalaxias mesotes at Woods Lake and Arthurs Lake).


1 INTRODUCTION

1.1 Pedder galaxias (Galaxias pedderensis)

The Pedder galaxias (Galaxias pedderensis) is Australia's most endangered fish (Hamr 1995). The species was first described in 1968 (Frankenberg 1968) from Lake Pedder in south-western Tasmania. The Pedder galaxias formerly inhabited the original Lake Pedder and surrounding streams and swamps. When Lake Pedder was flooded in the early 1970's, the Pedder galaxias increased in numbers and was very abundant by the mid 1970's. However, by the mid 1980's, very few Pedder galaxias were left. It is believed that the decline of the Pedder galaxias was due to predation and/or competition with increasing populations of introduced brown trout (Salmo trutta) and climbing galaxias (Galaxias brevipinnis).

Currently, the Pedder galaxias is on the verge of extinction in Lake Pedder. In the past five years, extensive surveys have yielded only five fish from two small streams draining into Bonnet Bay on the eastern side of Lake Pedder. The main hope for recovery of the species now lies in a small population translocated to Lake Oberon in 1991-92. An attempt is also being made to establish a second translocated population at the Strathgordon water supply dam near Lake Pedder.

1.1.1 Description of species

The Pedder galaxias is a medium to large galaxiid species with a slender elongate body and a dorsally compressed head. Adults typically range from 75-120 mm although the largest recorded specimen was 156 mm in length. The colour of the upper body and sides are a light grey-brown with irregular dark blotches. Gold flecks are also usually present on the dorsal surface and sides. The ventral surface is a grey-white colour and the fins are yellow-brown.

Figure1 The Pedder galaxias

Figure 1: The Pedder galaxias (Galaxias pedderensis).

1.1.2 Distribution

Prior to the construction of the Gordon Power Scheme in the early 1970's, the Pedder galaxias was naturally restricted to the original Lake Pedder and adjoining streams. Following inundation of the old lake, there was an initial population increase of Pedder galaxias. The distribution of the Pedder galaxias increased throughout the new lake as well as into the Wedge River, Lake Gordon and McPartlans canal (Andrews 1976, Hamr 1992).

During the 1970's, large schools of Pedder galaxias were observed throughout the new Lake Pedder. However, by the early 1980's, it was reported that numbers were rapidly declining (Raadik and Lake unpubl. data). Surveys by the IFC in 1988-89 revealed that very few Pedder galaxias remained. The species was found to be present in only four streams flowing into Lake Pedder: Bonnet Bay Creek 1, Bonnet Bay Creek 2, Pebbly Creek, and Swampy Creek. A more intensive study conducted in 1990-91 failed to collect Pedder galaxias from Pebbly Creek and Swampy Creek although a reasonable number remained at the Bonnet Bay Creeks. One Pedder galaxias was collected from Stillwater Rivulet during this survey.

In 1991-92, 31 Pedder galaxias were released into Lake Oberon in the western Arthur Range to the south of Lake Pedder. Surveys of Lake Oberon in 1997 showed that Pedder galaxias had spawned successfully and a small population had become established in the lake.

Intensive surveys of Lake Pedder conducted by the IFC between 1994 and 1997 resulted in the collection of only five Pedder galaxias. All five fish were collected from the Bonnet Bay streams. Three of these fish were subsequently transferred to Lake Oberon. The results of the surveys conducted in recent years suggest that the Pedder galaxias is extremely close to extinction within Lake Pedder and that only a few fish probably remain in the two Bonnet Bay streams. The current distribution of the Pedder galaxias is shown in the map on the following page.

1.1.3 Habitat

Prior to the flooding of Lake Pedder, Pedder galaxias inhabited the lake and surrounding swamps and streams. Lake Pedder itself was relatively shallow with a predominantly sandy substrate. There were a number of swamps and meandering streams surrounding the lake with abundant aquatic and overhanging terrestrial vegetation. Pedder galaxias were also found in the slower flowing regions of several steeper streams draining the ranges to the north and south.

When the lake was flooded in the 1970's, Lake Pedder was transformed into a very large and relatively deep lake. The swamps, meandering streams and original lake were flooded beneath more than 20 m of water. The steeper streams were the only areas of natural habitat that remained unchanged after the flooding of Lake Pedder.

In the late 1970's, Pedder galaxias were extremely common around the new lake. Juveniles were reported swimming around the lake shores in large schools and adults were common in streams draining into the lake and around the lake shores. In the last fifteen years, Pedder galaxias have only been recorded in the lower meandering regions of a few small streams flowing into Lake Pedder.

1.1.4 Life history and ecology

The Pedder galaxias spawns in spring as water temperatures begin to rise. In an artificial stream, captive fish laid their eggs under flat rocks, aquatic vegetation and submerged woody debris (Hamr 1992). Most Pedder galaxias appear to breed at three to four years of age. The number of ovarian eggs produced is relatively small and varies between 150-1200 depending on the size of the female.

Artificially fertilised eggs take 22-30 days to hatch at 15-16oC. Larvae are approximately 10 mm in length upon hatching and feed on small aquatic crustaceans. Prior to the population decline, larval fish were observed and collected from schools swimming around the edges of the lake. It appears likely that the original lake served as a nursery area for pelagic larvae and juveniles. Adult Pedder galaxias feed primarily upon terrestrial insects and aquatic insects and crustaceans (Hamr 1992).

Figure 2: Map of Lake Pedder area showing land tenure.

Pedder galaxias were last collected from two streams flowing into Bonnet Bay in 1996. A small translocated population of Pedder galaxias exists at Lake Oberon in the Western Arthur Range to the south of Lake Pedder. The Strathgordon water supply dam has been altered to provide an artificial habitat for Pedder galaxias and is located near Strathgordon village. McPartlans Canal links Lake Pedder and Lake Gordon and has been managed to minimise the risk of redfin perch introduction to lake Pedder.

1.1.5 Reasons for listing

The conservation status of the Pedder galaxias is Endangered (ASFB 1995, Wager and Jackson 1993). It is listed nationally in Schedule 1, Part 1 (Endangered) of the Endangered Species Protection Act 1992 and in Schedule 3, Part 1 (Endangered) of the Tasmanian Threatened Species Protection Act 1995.

The Pedder galaxias has undergone a dramatic decline in numbers in the last 15 years and is now Australia's most endangered fish (Hamr 1995). The decline in Pedder galaxias numbers is thought to be due to predation and/or competition with brown trout and climbing galaxias which were introduced to Lake Pedder when it was flooded in the early 1970's. The Pedder galaxias is on the verge of extinction in Lake Pedder and it is likely that only a few individual fish are left in two streams at Bonnet Bay. A small translocated population exists at Lake Oberon in the western Arthur Range to the south of Lake Pedder.

1.1.6 Existing conservation measures

In 1991-92, a series of translocations of Pedder galaxias into Lake Oberon in the western Arthur Range was conducted. A total of 31 fish were released into the lake, including 20 fish collected from the Bonnet Bay streams and 11 juveniles raised in captivity. In 1997, an additonal three fish were translocated from the Bonnet Bay streams to Lake Oberon. Lake Oberon has been surveyed by the IFC at least once each year since the fish were released. Recent surveys confirmed that a small breeding population exists at the lake.

The first recovery plan for the Pedder galaxias (Gaffney, Hamr and Davies 1992) was prepared to guide recovery efforts for the species. The IFC was the lead agency for the implementation of the plan. Actions outlined in the recovery plan included the capture and transfer of adult stock to Lake Oberon, monitoring of the Bonnet Bay populations, monitoring of the Lake Oberon population, captive breeding, and transfer of stock to an additional site. The current recovery plan is intended to replace the actions outlined in the first recovery plan.

In April 1994, a recovery team was formed to guide the recovery of the Pedder galaxias. In May 1996, this team was merged with the Swan galaxias recovery team to form the Tasmanian Galaxiid Recovery Team to guide conservation efforts for Tasmania's threatened galaxiid species.

In 1996, modified operating procedures for the Gordon Power Scheme were implemented by the HEC in an attempt to prevent the colonisation of Lake Pedder by redfin perch from Lake Gordon. Redfin perch represent a significant threat to the galaxiid populations of Lake Pedder. The modified procedures require the level of Lake Pedder to be kept at least 1 m above that of Lake Gordon before the radial gates on the canal linking the lakes are opened. By maintaining this difference in levels, the flow rate through the radial gates is estimated to be too swift to allow redfin to pass.

In 1997, the water supply dam at Strathgordon near Lake Pedder was drained and works were carried out to convert the dam into an artificial habitat for Pedder galaxias. This action is intended to provide an accessible second translocation site for the Pedder galaxias. Four fish collected in January 1996 were held at the water supply dam. In May 1997, the three surviving fish were released into Lake Oberon. It is hoped that in the future, a reasonable number of fish can be collected from either the Bonnet Bay streams or Lake Oberon to establish a breeding population at the Strathgordon dam.

1.1.7 Strategy for recovery

The Lake Pedder impoundment is no longer a suitable habitat for the Pedder galaxias due to the presence of introduced fishes. Consequently, recovery efforts for the species must focus on establishing translocated populations in other localities. The time and effort put into collecting and releasing 31 Pedder galaxias into Lake Oberon appears to have been rewarded. Recent surveys of the lake have shown that the species is reproducing in the lake and that a small population exists. The apparent success of the Lake Oberon translocation shows the potential of translocations for recovery of the Pedder galaxias. As part of this recovery plan, the status of the Lake Oberon translocation will be monitored and a second translocation will be attempted.

As it appears that the Lake Oberon population may be slowly building up in numbers, the next five years are critical to the direction of the recovery process for the species. The actions outlined for the Lake Oberon population consist of a series of video and electrofishing surveys to monitor the reproductive success and size of the population. The information obtained from these surveys will allow the status of the population to be accurately followed and will serve as a guide for future conservation efforts aimed at the Pedder galaxias.

Attempts will be made to establish a second translocated population at the more accessible Strathgordon water supply dam. The HEC-funded works on the dam are designed to create an artificial habitat for the Pedder galaxias. Further extensive surveys of the Bonnet Bay streams will be conducted as part of the recovery plan in an attempt to obtain more fish to add to the Lake Oberon population or to establish a population at the Strathgordon dam. Whilst it is not currently considered appropriate to collect fish from Lake Oberon to add to the Strathgordon dam population, this may be considered in the future if the size of the Lake Oberon population builds up sufficiently.

A threatened galaxiids captive breeding program will be conducted as part of the recovery plan and will provide benefits for the Pedder galaxias. Whilst Pedder galaxias are unlikely to be used in the initial trials, information regarding the handling of adults and rearing of larvae for other galaxiid species may allow artificial rearing of Pedder galaxias to be attempted again in the future. Captive rearing of Pedder galaxias could become important for the establishment of further translocated populations.

Finally, the Pedder galaxias will be included in a public information and education campaign to increase the profile of Tasmania's threatened galaxiid fishes. As the Pedder galaxias already has a high profile and has a reasonable chance of recovery, it will certainly be a major part of this campaign.

1.2 Swan galaxias (Galaxias fontanus)

The Swan galaxias (Galaxias fontanus) was described (Fulton 1978) following the discovery of a population above Hardings Falls on the Swan River in eastern Tasmania. Access to this area was made possible by roadworks associated with forestry development. Following the discovery of the Swan River population, several other streams in the area were surveyed for galaxiids without success. Fulton (1978) demonstrated that the downstream limit of the galaxiid population coincided with a natural barrier to brown trout invasion, and postulated that the trout were responsible for the absence of galaxiids further downstream in the system.

The distribution, life history and environmental requirements of the species were studied in detail between 1987 and 1989 in a project funded by the World Wildlife Fund (now World Wide Fund for Nature). As a result of that project several management recommendations aimed at conserving the species were proposed (Sanger and Fulton 1991) and adopted in the 'Action Plan for Australian Freshwater Fish' (Wager and Jackson 1993). Using the recommendations as a basis, the first recovery plan for the Swan galaxias was prepared in 1993 (Sanger 1993).

As part of the first recovery plan, a series of translocations was attempted. Currently, twelve breeding populations of Swan galaxias exist including three natural and nine translocated populations. With the success of the translocation actions, the recovery criteria outlined in the recovery plan were met. However, the long term stability and viability of these populations must be proven prior to down listing of the species.

This recovery plan is the second prepared for the species and is intended to replace the actions outlined in the first recovery plan. The current plan consists mainly of a regime of monitoring to ensure the long term viability of the twelve populations of Swan galaxias. It is expected that the Swan galaxias will be down listed by the end of the recovery plan period should the natural and translocated populations prove stable over the next few years. If so, the Swan galaxias may be the first freshwater fish to be downlisted as a result of successful recovery measures.

1.2.1 Description of species

The Swan galaxias is a small to medium sized galaxiid that grows to about 130 mm in length. The colour fades from a light olive-green on the back to creamy white on the ventral surface. Pale brown speckling on the sides and back may form irregular bars and patches. The dorsal fin originates above the vent and the caudal fin is only slightly forked. The pectoral fins are relatively small and extend less than half of the way back to the pelvic fins. The fins are unmarked. The head is broad and flattened dorsally and the eyes are located at the dorsal profile.

Figure 3 The Swan galaxias

Figure 3: The Swan galaxias (Galaxias fontanus).

1.2.2 Distribution

The Swan galaxias is an endemic species found only in a few streams in eastern Tasmania. As the species was discovered after the introduction of brown trout to the Swan and Macquarie River catchments, the original distribution of the Swan galaxias is unknown. However, it is likely that the species was widespread in the catchments prior to the introduction of trout. After its description from the Swan River in 1978, four natural populations of Swan galaxias were discovered in the headwaters of small tributaries of the Macquarie River (Sanger and Fulton 1991). Two of these populations have recently become extinct due to the spread of brown trout and redfin perch. Natural populations of Swan galaxias currently exist in the Upper Swan River and in Blue Tier Creek and Tater Garden Creek in the Macquarie River catchment. Nine translocated populations of Swan galaxias have been established since 1987. The locations of these populations are shown in the map below.

Figure 4: Distribution of Swan galaxias

1 St Pauls River- translocated 8 Wye River - failed translocated
2 Dukes River - translocated 9 Upper Blue Tier Creek -translocated
3 Tullochgorum Creek - translocated 10 Lower Blue Tier Creek- natural
4 Swan River - natural 11 Tater Garden Creek - natural
5 Cygnet River - translocated 12 Green Tier Creek - translocated
6 Coghlans Creek - translocated 13 Rocka Rivulet - translocated
7 Lost Falls Creek - translocated  

1.2.3 Habitat

The Swan galaxias is the only species of endemic Tasmanian galaxiid that lives exclusively in freshwater streams. The species is confined to the headwaters of small streams that are inaccessible to introduced fish species. The streams occupied by Swan galaxias are generally shallow with abundant instream and riparian cover.

1.2.4 Life history and ecology

Swan galaxias spawn in spring within the normal adult habitat. Larval development extends over a period of at least five weeks and the larvae occupy shallow, slow flowing water in small groups. At around 35 mm length, the larvae begin to develop adult colouration. Typically, there are three year classes present in each population. Swan galaxias are opportunistic carnivores and feed upon a wide variety of terrestrial and aquatic prey.

1.2.5 Reasons for listing

The conservation status of the Swan galaxias is Endangered (ASFB 1995, Wager and Jackson 1993). It is listed nationally in Schedule 1, Part 1 (Endangered) of the Endangered Species Protection Act 1992 and in Schedule 3, Part 1 (Endangered) of the Tasmanian Threatened Species Protection Act 1995.

The natural distribution of the Swan galaxias has become fragmented and is presently confined to three small populations in the extreme headwaters of a few streams. Two of the five natural populations discovered since the description of the species in 1978 have become extinct due to the spread of introduced fish. The Swan galaxias is unable to co-exist with brown trout or redfin perch due to predation and/or competition with these species.

As part of a translocation program aimed at extending the range of the Swan galaxias, nine breeding populations have become established in streams that did not previously contain fish. If these translocated populations remain stable over the next few years, it is likely that the species will be down listed.

1.2.6 Existing conservation measures

A detailed study of the distribution, life history and environmental requirements of the Swan galaxias was conducted by the IFC in 1987-89 with funds provided by the World Wildlife Fund Australia (now World Wide Fund for Nature). Arising from this study were a number of recommendations including listing of the areas containing natural populations of Swan galaxias as Forestry Tasmania Wildlife Priority Areas.

In 1989, a small natural barrier to trout in Blue Tier Creek was made more effective by increasing its height and slope. No trout have invaded the upstream part of the creek since the barrier was improved.

Based on the recommendations of Sanger and Fulton (1991), the first recovery plan for the Swan galaxias was prepared in 1993 (Sanger 1993). Actions included in the recovery plan were a translocation program, the construction of artificial barriers to introduced fish, monitoring of natural populations, the establishment of captive populations and an information and education campaign. In 1994, a Swan galaxias recovery team was formed to oversee recovery efforts for the Swan galaxias. This recovery team was merged with the Pedder galaxias recovery team in 1996 to form the Tasmanian Galaxiid Recovery Team to guide conservation efforts for threatened Tasmanian galaxiids.

1.2.7 Strategy for recovery

With the establishment of nine translocated populations of Swan galaxias, the prospects for formal down listing of the species are very good. However, before proceeding with any attempts at down listing, the long term stability and viability of the natural and translocated populations must be firmly established. The core actions outlined for the Swan galaxias in this recovery plan consist of a program of regular monitoring to achieve this goal.

Habitat critical to the survival of the Swan galaxias will be identified and submitted for listing under State threatened species legislation. The Swan galaxias will be included in the captive breeding program for threatened galaxiids. The development of detailed protocols for captive breeding of the species will allow release of captively reared fish to be adopted as a management strategy if this becomes necessary in the future. Finally, the Swan galaxias will be included in the public information and education action to increase awareness of Tasmania's unique galaxiid fauna within the community.

1.3 Clarence galaxias (Galaxias johnstoni)

The Clarence galaxias (Galaxias johnstoni) is a freshwater fish endemic to the Clarence River catchment in central Tasmania. It was first described in 1936 from specimens collected in a tributary of the lower Clarence River (Scott 1936). It is now absent from this area and is entirely restricted to the upper Clarence River catchment. The decline of the Clarence galaxias is almost certainly due to the spread of brown trout within the catchment. Clarence galaxias do not occur in areas where brown trout have colonised. Brown trout are thought to outcompete and/or prey upon Clarence galaxias.

Five populations of Clarence galaxias are currently known including a major population at Clarence lagoon that occurs in sympatry with brook trout (Salvelinus fontinalis). The brook trout population at Clarence Lagoon has been actively maintained by the IFC since the 1960's and provides a relatively benign alternative to brown trout for the anglers who fish this water. The other four populations of Clarence galaxias do not share their habitats with other fish species.

1.3.1 Description

The Clarence galaxias is a small to moderate sized galaxiid fish that reaches a maximum length of approximately 120 mm and lives to around four years of age. Juveniles are lightly pigmented and begin to develop adult colouration at approximately 40 mm. Adults are usually dark brown on the back with this colour extending down the sides in bars and irregular bands and patches, becoming lighter towards the ventral surface. The belly is usually yellowish in colour. Numerous very small black spots are often present, but these are parasites rather than natural markings (Fulton 1990).

Figure 5 The Clarence galaxias

Figure 5: The Clarence galaxias (Galaxias johnstoni).

1.3.2 Distribution

The Clarence galaxias is an endemic Tasmanian species found only in the Clarence River catchment. The distribution of the species was extensively surveyed in 1987-89 and only five populations were discovered (Sanger and Fulton 1991). The species is no longer present in the lower Clarence River catchment where it was first described in the 1930's.

The current distribution of the Clarence galaxias is shown in the following map. A relatively large population exists at Clarence Lagoon in sympatry with brook trout and a small population exists in an unnamed lagoon upstream of Clarence Lagoon. A significant population exists in an unnamed lagoon in the Wentworth Hills to the south and two small populations occur in the headwaters of Dyes Rivulet and Dyes Marsh to the south-west of Clarence Lagoon.

The reduction in the range of the Clarence galaxias is almost certainly due to the spread of brown trout throughout the catchment; the species is not found in sympatric association with brown trout. As brown trout were introduced into the Clarence River catchment prior to the discovery of the Clarence galaxias, the original distribution of the Clarence galaxias is unknown. However, the collection of specimens from the lower catchment in the 1930's (Scott 1936) shows that the Clarence galaxias was more widely distributed in the recent past than it is at present.

1.3.3 Habitat

Within its current range, adult Clarence galaxias occupy stream, marsh and lake habitats. The variety of habitat types occupied shows that the species is not highly selective in its habitat requirements. However, requirements for spawning and/or larval development may be more specific. The distribution of the Clarence galaxias is limited by the presence of brown trout in otherwise suitable habitats.

1.3.4 Life history and ecology

The Clarence galaxias spawns in spring. Eggs have been found laid in masses adhering to rocks in the lower reaches of a stream flowing into the lagoon at Wentworth Hills. The eggs take approximately two months to hatch and larvae have been observed swimming in open water in small schools. At around 40 mm length, juveniles begin to develop the adult colouration and take on a benthic habit. Larvae and small juveniles feed on planktonic crustaceans while the diet of larger fish is comprised mainly of benthic crustaceans and insects.

1.3.5 Reasons for listing

The conservation status of the Clarence galaxias is Endangered (ASFB 1995, Wager and Jackson 1993). It is listed nationally in Schedule 1, Part 1 (Endangered) of the Endangered Species Protection Act 1992 and in Schedule 3, Part 1 (Endangered) of the Tasmanian Threatened Species Protection Act 1995.

Clarence galaxias cannot co-exist with brown trout due to predation and/or competition with this species. From a former distribution that probably included most of the Clarence River system, the range of the Clarence galaxias has been reduced to the extent that only five known populations occur in waters that remain isolated from brown trout. Further introductions of brown trout into the remaining habitats occupied by Clarence galaxias, either by natural dispersal or illegal introduction, are a significant threat to the species.

Figure 6: Current distribution of the Clarence galaxias.

A population exists in sympatry with brook trout at Clarence Lagoon and in the upper Clarence River. Populations isolated from introduced fish occur at an unnamed lagoon in the Wentworth hills, at Dyes Marsh, and in the swamp area immediately north of Clarence Lagoon. Brown trout are present throughout the lower Clarence River catchment and in Laughing Jack Lagoon.

1.3.6 Existing conservation measures

A detailed study of the distribution, life history and environmental requirements of the Clarence galaxias was conducted by the IFC in 1987-89 with funds provided by the World Wildlife Fund Australia (now World Wide Fund for Nature). The populations at Dyes Marsh and upstream of Clarence Lagoon were discovered during this study. A series of management recommendations were produced in the report arising from the study (Sanger and Fulton 1991) suggesting that:

  • 1. the species' conservation status remain Endangered;
  • 2. habitat protection measures be actively promoted;
  • 3. IFC stocking policy recognise the vulnerability of Clarence galaxias to brown trout;
  • 4. translocated populations be established in suitable waters.

Currently, the known populations of Clarence galaxias are monitored intermittently by the IFC. The habitats occupied by the three largest and most important populations of Clarence galaxias are reserved for nature conservation. Clarence Lagoon and its catchment are included in the Tasmanian Wilderness World Heritage Area and also have interim listing on the Register of the National Estate as part of the Clarence Lagoon-Wild Dog extension area. Wentworth Hills has been classified as a Forestry Tasmania Wildlife Priority Area with the specific recommendation that no road access be developed to this locality.

1.3.7 Strategy for recovery

The strategy for recovery of the Clarence galaxias is largely based upon the Pedder and Swan galaxias recovery plans (Gaffney, Hamr and Davies 1992; Sanger 1993). In a very similar situation to the decline of the Swan galaxias, the Clarence galaxias is not capable of survival in the presence of brown trout. Consequently, the core actions for the recovery of the Clarence galaxias are the protection of remaining natural populations from brown trout colonisation and an extension of the range of the species via a series of translocations.

The remaining natural populations of Clarence galaxias will be monitored regularly throughout the recovery plan period to ensure that they remain viable and isolated from brown trout. Artificial barriers will be installed if appropriate locations can be identified to restrict the movement of brown trout into habitats occupied by Clarence galaxias.

Translocated populations will be established in at least five locations within or near the Clarence River catchment. Prior to translocation, each potential site will be assessed for its suitability with regards to water permanency, accessibility, presence of other fish species and presence of other threatened fauna. Translocated populations will be monitored routinely to ensure their ongoing viability and isolation from brown trout.

The maintenance of a trout stocking policy by the IFC that gives highest priority to conservation of the Clarence galaxias is viewed as a major factor in habitat management for the species. Control of brown trout via removal and barrier construction are also seen as potentially important facets of habitat management. The three most significant populations of Clarence galaxias are well reserved for nature conservation. In addition to this protection, critical habitat will be identified and submitted for listing under the Threatened Species Protection Act 1995.

The Clarence galaxias will be included in the captive breeding program for threatened galaxiids. The development of detailed protocols for captive breeding of the species will allow release of captively reared fish to be adopted as a management strategy if this becomes necessary in the future. The techniques will also provide information directly applicable to the successful captive breeding of other threatened galaxiids and will involve interested members of the public in the recovery process.

Finally, the Clarence galaxias will be included in the public information and education action to increase awareness of Tasmania's unique galaxiid fauna within the community.

1.4 Swamp galaxias (Galaxias parvus)

Two species of fish are endemic to the Lake Pedder area in south-western Tasmania. One of these, the Pedder galaxias (Galaxias pedderensis) has declined rapidly in recent years due to interactions with climbing galaxias and brown trout. The swamp galaxias (Galaxias parvus) on the other hand, has remained relatively common within its restricted range.

Prior to the flooding of the original Lake Pedder, the swamp galaxias was found in the small streams and extensive swamps that surrounded the original lake as well as in tributaries of the Wedge and Huon Rivers (Frankenberg 1968). When Lake Pedder was flooded in the 1970's, large areas of habitat were inundated and the species is currently found in swamps and streams surrounding the new lake margins.

Brown trout and climbing galaxias colonised Lake Pedder soon after it was flooded and rapidly established large populations. Unlike the Pedder galaxias, the swamp galaxias remained relatively common in the presence of these populations. However, the changing dynamics of the fish populations in the new Lake Pedder mean that the indefinite survival of the swamp galaxias cannot be assured.

The trout and Pedder galaxias populations in Lake Pedder expanded rapidly in the first decade after flooding. This initially resulted in phenomenal growth by trout and a boom period in the recreational fishery. More recently however, the lake has become overpopulated with small trout and the Pedder galaxias has effectively disappeared from Lake Pedder. The climbing galaxias population also increased rapidly during this time and is now the dominant fish species in many of the streams flowing into Lake Pedder. Until the fish populations of Lake Pedder stabilise over the long term, it cannot be assumed that the swamp galaxias will continue to remain common within its current range.

In addition to the threats posed by the introduced species already within Lake Pedder, redfin perch may present a future threat to the swamp galaxias. Redfin are aggressive piscivores and have already been implicated in a local extinction of the Swan galaxias Galaxias fontanus (Sanger 1993). Although redfin have not yet been recorded in Lake Pedder, nearby Lake Gordon supports a massive redfin population. Lake Pedder is linked to Lake Gordon via a large canal whose flow is controlled by a single set of radial gates. At present, these gates are the only barrier to the invasion of Lake Pedder by redfin and it is not known if any have managed to migrate into Lake Pedder.

There is very little that can be done to prevent redfin colonisation once they have entered the lake as there is no available method for complete removal of fish from such a large body of water. If redfin become established in Lake Pedder, isolated populations of swamp galaxias are essential to ensure the long term survival of the species.

1.4.1 Description of species

The swamp galaxias is a small to moderate sized galaxiid that reaches a maximum length of approximately 100 mm. Juveniles are lightly pigmented and begin to develop adult colouration at approximately 35-40 mm. Adults are a light brown on the back and fin bases with irregular and sparse small spots and flecks over the body. The stomach region often appears pale orange to yellow becoming lighter on the undersurface (Fulton 1990).

Figure 7 The Swamp Galaxias

Figure 7: The swamp galaxias (Galaxias parvus).

1.4.2 Distribution

Prior to flooding of the original Lake Pedder, the swamp galaxias was found mainly in the streams and extensive swamps that surrounded the original lake and in tributaries of the Wedge and Huon rivers. When Lake Pedder was flooded, large areas of habitat were inundated. Currently, populations of the species are found in swamps and streams surrounding the new lake margins. The swamp galaxias is not generally found in the main body of Lake Pedder (Fulton 1990; Hamr 1992). The map on the following page shows the known distribution of the swamp galaxias.

1.4.3 Habitat

The swamp galaxias inhabits shallow vegetated margins of swamps and backwaters and pools within streams. Juvenile fish have been observed swimming amongst vegetation around the margins of streams and around the lake shores (Hamr 1992).

1.4.4 Life history and ecology

The diet of the swamp galaxias consists mainly of terrestrial insects and aquatic crustacea. Breeding occurs in early spring. Spawning sites for fish in the wild have not been described although a female kept in an aquarium deposited eggs on gravel under a rock shelter. The swamp galaxias produces a relatively small number (70-500) of large eggs (1.6-2.6 mm) which take 50-60 days to hatch (Hamr 1992). Juvenile stages occupy shallow vegetated margins before taking on the cryptic and benthic habits of the adults at around 35-40 mm.

1.4.5 Reasons for listing

Due to a lack of knowledge regarding the abundance and distribution of the swamp galaxias prior to the flooding of Lake Pedder, the extent of decline of this species is uncertain. As a consequence, the conservation status of the species has not been uniformly agreed upon. The swamp galaxias is listed as Potentially Threatened by ASFB (1995), Poorly Known by Wager and Jackson (1993), Vulnerable in Schedule 1, Part 2 of the Endangered Species Protection Act 1992, and is not listed in the Tasmanian Threatened Species Protection Act 1995. Under IUCN criteria, the species may be classified as Endangered based upon a projected population decline should redfin perch colonise Lake Pedder. Clearly, there is a need for accurate determination of the conservation status of the swamp galaxias.

1.4.6 Existing conservation measures

Aspects of the ecology of the swamp galaxias were examined during conservation efforts directed towards the Pedder galaxias from 1988-91 (Hamr 1992). Details of the life history and environmental requirements of the species were examined and a distributional survey conducted. Captive breeding was attempted during this time and a number of larvae were successfully reared.

In consultation with the IFC, the HEC implemented modified operating procedures for the McPartlans Canal gates in 1996 to minimise the risk of redfin perch introduction into Lake Pedder. If successful, this will benefit conservation efforts for the Pedder galaxias and the swamp galaxias. Most of the habitats occupied by swamp galaxias are well reserved for nature conservation with most included in the South-West Wilderness World Heritage Area and the remainder within crown land managed by the HEC.

1.4.7 Strategy for recovery

Although the modified operating regime at McPartlans Canal greatly reduces the chances of redfin migrating into Lake Pedder, the threat of illegal introductions of undesirable fish by humans is ever present. Additionally, little can be done to control the abundance of trout and climbing galaxias in Lake Pedder. Consequently, the focus of this recovery plan is to secure the long term survival of the swamp galaxias by ensuring that an adequate number of viable populations exist in habitats that will remain isolated from introduced fish in the long term.

The actions outlined in the recovery plan include a detailed survey of the current distribution of the swamp galaxias and an assessment of the accessibility of populations to introduced fish species. If necessary, a number of translocated populations will be established in the Lake Pedder area to bring the total number of known populations isolated from introduced fish species to at least twenty. Prior to any translocations, the invertebrate fauna of prospective sites will be sampled and the presence of any threatened species or communities will be determined. Natural and translocated populations will be monitored regularly to assess their ongoing viability and isolation from introduced fish species.

The swamp galaxias will be included in the threatened galaxiids captive breeding program. The development of detailed protocols for captive breeding of the species will allow release of captively reared fish to be adopted as a management strategy if this becomes necessary in the future. The techniques will also provide information directly applicable to the successful captive breeding of other threatened galaxiids and will involve interested members of the public in the recovery process.

Modifications to HEC operating procedures have been implemented to minimise the risks of redfin perch introduction into Lake Pedder. Further consultation with the HEC regarding threatened fish management will continue throughout the life of the recovery plan. Critical habitat will be determined and submitted for listing under the Threatened Species Protection Act 1995 to provide legislative protection for the habitats occupied by the species. Finally, the swamp galaxias will be included in the public information and education action to increase awareness of Tasmania's unique galaxiid fauna within the community.

Figure 8: Known distribution of swamp galaxias.

Yellow symbols (¢ )represent sites where swamp galaxias were recorded in electrofishing surveys conducted by the IFC between 1990 and 1992 (Hamr 1992).

1.5 Saddled galaxias (Galaxias tanycephalus)

The saddled galaxias (Galaxias tanycephalus) is an endemic species found only in Arthurs Lake and Woods Lake in Tasmania's Central Highlands. The species was described by Fulton (1978) from specimens collected from Arthurs Lake in 1976. Both of the lakes in which the saddled galaxias occurs are natural lakes that were raised by dams constructed by the HEC. Brown trout were introduced into the systems at around the turn of the century and saddled galaxias have almost certainly been preyed upon heavily by trout in both lakes since this time. Despite this predation, the species has maintained a sparse population in Arthurs Lake and an abundant population at Woods Lake. Whilst the current levels of trout predation appear sustainable, at least in Woods Lake, the possibility of future introductions of undesirable species poses an ongoing threat to the saddled galaxias. European carp are present in Lake Sorell and Lake Crescent only 8 km to the east of Woods Lake and redfin perch are present in the Lagoon of Islands only 2 km to the south-west.

In addition to the impacts of introduced fish, deteriorations in the quality of habitat also pose potential threats to the saddled galaxias. Water quality has been a concern at Woods Lake for a number of years and is regularly monitored by the HEC and IFC. The Ripple Creek diversion canal directs nutrient rich water into the lake for much of the year and it is likely that these nutrients contribute to the severity of periodic phytoplankton blooms. Drawdowns of Woods Lake for the supply of irrigation water have also caused water quality deteriorations and dewatering of saddled galaxias habitat.

1.5.1 Description of species

The saddled galaxias grows to a maximum length of about 150 mm. The markings of the species appear as series of saddles that cover the back and sides. This pattern sometimes gives way to large oval spots which become confluent towards the back. Smaller fish are dark olive on the back, yellow-green around the markings, with a silver belly. Larger specimens may appear black on the back and sides with a purple sheen and a greyish belly. The dorsal and anal fins may have black edges but this is not usual (Fulton 1990).

Figure 9 The Saddled galaxias

Figure 9: The saddled galaxias (Galaxias tanycephalus).

1.5.2 Distribution

The distribution of the saddled galaxias is confined to Arthurs Lake and Woods Lake in the Central Highlands of Tasmania. The locations of these lakes are shown in the map below. The saddled galaxias is uncommon in Arthurs Lake and is abundant in Woods Lake. Possible reasons for the smaller size of the population at Arthurs Lake are the lake's very large trout population, high water clarity and relatively low planktonic productivity. Although Woods Lake also has a large trout population, it is more turbid, which probably reduces predation by trout, and has higher planktonic productivity, which probably increases recruitment of the pelagic larvae and juveniles into the adult population (Sanger and Fulton 1991).

Figure 10: Distribution of the saddled galaxias.

Populations occur at Arthurs Lake, Woods Lake and in the Lake River between these two lakes. The saddled galaxias occurs in sympatry with brown trout throughout its range. Redfin perch are present in the Lagoon of Islands 2 km to the south-west of Woods Lake and European carp are present in Lake Sorell and Lake Crescent 8 km to the south-east.

1.5.3 Habitat

The species is almost exclusively lacustrine with adults occupying rocky lake margins and the planktonic larval and juvenile stages occupying open water.

1.5.4 Life history and ecology

Adult saddled galaxias are generally benthic in habit and feed mainly on benthic crustacea and aquatic insects (Fulton 1990). Larval and juvenile stages are planktonic and feed on planktonic crustacea. Saddled galaxias generally spawn at one year of age and there appears to be both autumn and spring spawning periods. Small larvae are present in Woods Lake all year round with a peak in summer (Sanger and Fulton 1991).

1.5.5 Reasons for listing

The saddled galaxias is listed as Vulnerable (ASFB 1995, Wager and Jackson 1993, Schedule 1, Part 2 Endangered Species Protection Act 1992, Schedule 4 Threatened Species Protection Act 1995) due to its acutely restricted distribution and low number of populations. The relatively low numbers of saddled galaxias in Arthurs Lake and its apparent absence from two small lakes connected to Arthurs Lake are seen as an indication of the vulnerability of the species to trout predation.

1.5.6 Existing conservation measures

A detailed study of the saddled galaxias was conducted by the IFC in 1987-89 with funds provided by the World Wildlife Fund Australia (now World Wide Fund for Nature). This study examined the distribution, life history and environmental requirements of the saddled galaxias. A report arising from the study (Sanger and Fulton 1991) recommended that:

  • 1. the conservation status of the species remain Vulnerable;
  • 2. habitat protection measures at Woods Lake be pursued;
  • 3. no enhancement of brown trout populations at Woods Lake occur;
  • 4. the possibility of establishing a translocated population be examined.

In 1995, Woods Lake was drawn down to an extremely low level by the HEC to provide irrigation water to farmers in the Lake River catchment. This resulted in a dramatic increase in turbidity in the lake and dewatering of much of the habitat of the saddled galaxias. Water column nutrient and chlorophyll levels also increased substantially during this period. At the time, concern was expressed by the IFC regarding the well being of the saddled galaxias and the HEC agreed to release water from Arthurs Lake to refill Woods Lake. This action, along with heavy rainfalls at the time, resulted in the raising of the lake's level and a subsequent improvement in water quality. The HEC has since instituted a new normal minimum operating level aimed at improving the habitat for the saddled galaxias at Woods Lake.

1.5.7 Strategy for recovery

In Woods Lake, the saddled galaxias population remains relatively abundant and trout predation, whilst considerable, appears to have a limited impact. At Arthurs Lake, the saddled galaxias is uncommon due, at least in part, to high levels of trout predation (Sanger and Fulton 1991).

There is little that can be done to reduce the impact of trout on saddled galaxias in either lake as both are large bodies of water that contain very abundant and naturally sustainable trout populations. Consequently, one of the actions outlined in this recovery plan aims at gaining knowledge of the population structure and dynamics of the saddled galaxias through regular monitoring. This knowledge will be particularly important if catastrophic declines similar to those of the Pedder galaxias were to occur amongst the saddled galaxias populations. In addition to the impact of trout, the presence of redfin perch and European carp in nearby lakes may present future threats to the saddled galaxias and increase the urgency for more detailed knowledge of the ecology of the species.

Deteriorations in water quality may also present threats to the two saddled galaxias populations. This is especially so at Woods Lake where high levels of turbidity, phytoplankton biomass and nutrient levels have been linked to lake management strategies (Sanger 1993, Crook 1995). One of the actions outlined in this recovery plan focuses on reducing the chances of decline of the species as a result of water quality deterioration. This will involve the continuation and formalisation of lake management strategies in consultation with the HEC that take the requirements of the saddled galaxias into account.

An assessment of the feasibility of translocating saddled galaxias will be conducted as part of the recovery plan. Sites identified as suitable for translocation must have similar characteristics to the natural habitats occupied by the species. The task of locating a suitable translocation site is more difficult for a species that naturally occurs in large lakes than for a species which occupies stream or swamp habitats. Surveys of the Lake River catchment have shown that there are no large lakes within or near the catchment that are free of introduced fish species. The feasibility of introducing saddled galaxias into two small lakes to the north of Arthurs Lake that contain trout populations will be examined and the potential of establishing populations within man-made dams will also be investigated.

The saddled galaxias will be included in the threatened galaxiids captive breeding program. The development of detailed protocols for captive breeding of the species will allow release of captively reared fish to be adopted as a management strategy if this becomes necessary in the future. The techniques will also provide information directly applicable to the successful captive breeding of other threatened galaxiids and will involve interested members of the public in the recovery process.

Studies of the Woods Lake population of saddled galaxias have suggested that the species has two main spawning periods during the year. This is unique amongst galaxiid fishes and may have implications regarding the genetic compositions of the Arthurs and Woods lakes populations. Preliminary work has shown that some degree of genetic separation exists between the larvae of spring and autumn spawnings and that two genetically distinct breeding stocks may exist at Woods Lake. A detailed study of the genetic composition of the two populations of saddled galaxias is included in the recovery plan to allow consideration of the genetic diversity within the two populations for future management.

Finally, the saddled galaxias will be included in the public information and education action to increase awareness of Tasmania's unique galaxiid fauna within the general community.


2 recovery plan Objectives and Criteria

2.1 Pedder galaxias

The long term objective is to improve the conservation status of the Pedder galaxias so that it no longer meets the ASFB or IUCN criteria for Endangered and can be down listed to Vulnerable. Within the five year span of this recovery plan, the objective is to ensure that the Pedder galaxias does not become extinct by establishing and monitoring two translocated populations.

Recovery will be assessed against the following criteria:

  • 1. At least two self maintaining translocated populations of the species should exist within five years. The minimum size of each of these populations should exceed 500 adult fish.
  • 2. Detailed protocols for captive breeding of the Pedder galaxias should be produced.

2.2 Swan galaxias

The objective is to improve the conservation status of the Swan galaxias so that it no longer meets the ASFB or IUCN criteria for Endangered and can be down listed to Vulnerable within five years.

Recovery will be assessed against the following criteria:

  • 1. At least ten self maintaining populations of the species should exist within five years. The minimum size of each of these populations should exceed 500 adult fish.
  • 2. No further population declines or reductions in range should occur due to interactions with introduced fish in the next five years.
  • 3. Detailed protocols for captive breeding of the Swan galaxias should be produced.

2.3 Clarence galaxias

The long term objective is to improve the conservation status of the Clarence galaxias so that it no longer meets the ASFB or IUCN criteria for Endangered and can be down listed to Vulnerable. Within the five year span of this recovery plan, the objective is to secure the existing natural populations of Clarence galaxias and to extend the range of the species by establishing five translocated populations.

Recovery will be assessed against the following criteria:

  • 1. At least ten self maintaining populations of the species should exist within five years. The minimum size of at least five of these populations should exceed 500 adult fish.
  • 2. No further population declines or reductions in range should occur due to interactions with introduced fish in the next five years.
  • 3. Detailed protocols for captive breeding of the Clarence galaxias should be produced.

2.4 Swamp galaxias

The objective of this recovery plan is to improve the conservation status of the swamp galaxias so that it meets the ASFB criteria for Restricted or the IUCN criteria for Lower Risk within five years.

Recovery will be assessed against the following criteria:

  • 1. At least 20 self maintaining populations, either natural or translocated, should be isolated from other fish species within five years. The minimum size of at least ten of these populations should exceed 300 adult fish.
  • 2. No further population declines or reductions in range should occur due to interactions with introduced fish in the next five years.
  • 3. Detailed protocols for captive breeding of the swamp galaxias should be produced.

2.5 Saddled galaxias

The long term objective is to improve the conservation status of the saddled galaxias so that it no longer meets the ASFB or IUCN criteria for Vulnerable and can be down listed to the ASFB Restricted or IUCN Lower Risk classifications. Within the five year time frame of this recovery plan, the objective is to secure the existing populations and develop and implement a strategy for increasing the range of the saddled galaxias.

Recovery will be assessed against the following criteria:

  • 1. An evaluation of all available options for translocation should be completed and its recommendations implemented.
  • 2. No further population declines or reductions in range should occur due to interactions with introduced fish or water quality deteriorations in the next five years.
  • 3. Detailed protocols for captive breeding of the saddled galaxias should be produced.

3 RECOVERY ACTIONS

The actions required to implement this recovery plan are described and costed over a five year period. Costs are based on 1997 prices and are for each financial year.

3.1 Recovery co-ordination

A project officer is required to oversee implementation of actions for the recovery of the five threatened galaxiids. This person will co-ordinate the actions outlined in the recovery plan, liaise with appropriate government and non-government organisations and report to the relevant funding agencies. The project officer will organise and chair recovery team meetings and will provide a contact point within the lead agency for recovery team members, relevant organisations and the general public. The project officer will oversee and assist in tasks requiring field work and will be responsible for the analysis of data and publication of results. A technical officer is also required to provide technical and general assistance.

COSTS

YEAR 1

YEAR 2

YEAR 3

YEAR 4

YEAR 5

TOTAL

TOTAL

73.0

75.5

79.5

82.0

84.0

394.0

3.2 Monitor natural populations

The rapid decline of the Pedder galaxias (Sanger and Fulton 1991; Hamr 1995) highlights the importance of continued monitoring of populations of threatened galaxiids. Given the restricted ranges of the five species included in this plan, it is essential that any significant population declines be detected quickly so that the reasons for the declines can be identified and acted upon. The following actions will provide an ongoing assessment of the stability of populations of the five species of threatened galaxiids.

3.2.1 Pedder galaxias

Surveys of Lake Pedder for Pedder galaxias will be conducted on a regular basis throughout the life of this recovery plan. Whilst the emphasis for recovery of the species has shifted towards the establishment of translocated populations, it remains important to continue searching Lake Pedder for any remaining wild fish. Given the very small numbers of Pedder galaxias left, any fish collected from the wild may add considerable genetic diversity to the translocated stocks. This may significantly enhance the chances of success of the translocated populations.

Approximately six field trips per year will be conducted. Any Pedder galaxias collected will be moved from Lake Pedder to one of the translocation sites.

COSTS

YEAR 1

YEAR 2

YEAR 3

YEAR 4

YEAR 5

TOTAL

TOTAL

6.0

6.0

6.0

6.0

6.0

30.0

3.2.2 Swan galaxias

To ensure that the three remaining natural populations remain viable and isolated from introduced fish species, regular electrofishing surveys will be conducted. Mark-recapture estimates of population size will be carried out and population structure will be examined. Two surveys per year are required to complete this action.

COSTS

YEAR 1

YEAR 2

YEAR 3

YEAR 4

YEAR 5

TOTAL

TOTAL

3.0

3.0

3.0

3.0

3.0

15.0

3.2.3 Clarence galaxias

The viability of the remaining natural populations of Clarence galaxias will be assessed by conducting electrofishing surveys. Fish will be collected using a backpack electrofishing unit and an assessment of population size and structure will be conducted. Surveys will be conducted twice yearly and will include the five remaining natural populations.

COSTS

YEAR 1

YEAR 2

YEAR 3

YEAR 4

YEAR 5

TOTAL

TOTAL

2.0

2.0

2.0

2.0

2.0

10.0

3.2.4 Swamp galaxias

As the swamp galaxias inhabits streams and swamps flowing into Lake Pedder, monitoring of natural populations of swamp galaxias will be incorporated into the surveys for Pedder galaxias. Fish will be collected using a backpack electrofishing unit and an assessment of population size and structure will be conducted.

In addition to this regular sampling, an extensive electrofishing survey of swamps and streams in the Lake Pedder area will be conducted in the first year of the recovery plan period. A detailed distribution map of the fish species collected will be produced and this will be used as a basis for the selection of translocation sites and for assessing the isolation of swamp galaxias populations from introduced fish.

COSTS

YEAR 1

YEAR 2

YEAR 3

YEAR 4

YEAR 5

TOTAL

TOTAL

2.0

-

-

-

-

2.0

3.2.5 Saddled galaxias

The two populations of saddled galaxias will be monitored regularly as part of the recovery plan. Adult and larval abundance will be monitored to assess seasonal breeding success and recruitment. As the species appears to have both winter and summer spawning periods, a more frequent monitoring regime than for single spawning species is required.

Four field trips per year are required for five years to monitor the two saddled galaxias populations. The IFC will provide accommodation, a vehicle and all other equipment required for the surveys.

Preliminary studies of the saddled galaxias (Elliott and Sanger unpubl.) have shown that there is a certain level of genetic divergence between larvae spawned in summer and those spawned in winter. A genetic study will be conducted in cooperation with CSIRO Marine Labs to determine whether there is sufficient divergence to suggest that there are two separate breeding populations of saddled galaxias in Woods Lake. The genetic composition of the population of saddled galaxias in Arthurs Lake will also be examined.

COSTS

YEAR 1

YEAR 2

YEAR 3

YEAR 4

YEAR 5

TOTAL

TOTAL

5.0

5.0

4.0

4.0

4.0

22.0

3.3 Establish and monitor translocated populations

The major threat facing Tasmania's threatened galaxiids is the presence of introduced fish which prey upon and/or compete with galaxiids. Consequently, the establishment of translocated populations in waters that are isolated from introduced fish is central to improving the conservation status of these fish. The translocations described in the following section are aimed at increasing the range of the species concerned to reduce the risks of extinction in the long term.

The IUCN (1987) position statement on the translocation of living organisms was considered in the formulation of the translocations proposed in this recovery plan. Whilst the proposed translocations conform to the position statement in other respects, the introduction of fish into natural habitats (habitats not perceptibly altered by man) does not conform to the generalised IUCN position. However, in the case of the threatened galaxiids, we consider such translocations justified.

In the case of the Pedder galaxias, the species would almost certainly be extinct within a few years if a translocation to Lake Oberon had not been conducted. There was considerable debate and consultation at the time regarding the decision to translocate Pedder galaxias to this relatively pristine lake. However, considering the imminent extinction of the species, it was eventually decided that the translocation was justified.

In the case of the Swan galaxias, only three small remnant populations would currently exist if translocations were not conducted. With a simple careless or vindictive act by a single person (ie. the release of brown trout or redfin perch) any of these populations could be decimated almost immediately. The translocated populations of Swan galaxias now provide a 'safety net' for the species.

The reclaimation of former habitat via the removal of introduced fish and subsequent restocking is obviously a preferable option for the recovery of the threatened galaxiids. Whilst this approach will certainly be considered at all stages, it must be recognised that the eradication of fish is invariably difficult and often impossible in practice. Translocations, if conducted in a careful and responsible manner, provide an effective means of improving the conservation status of threatened galaxiids without significantly impacting on other important components of the Tasmanian fauna.

3.3.1 Pedder galaxias

The focus of recovery efforts for the Pedder galaxias now lies in the successful establishment of translocated populations. To ensure that translocated populations become established and remain viable, populations must be monitored on a regular basis.

The Lake Oberon population will be monitored once per year. Each survey will consist of electrofishing and underwater video surveys to estimate reproductive success and population size. At the Strathgordon water supply dam, the artificial stream will be revegetated and instream habitat will be provided by collecting rocks and woody debris from Lake Pedder streams. If the recovery team considers it appropriate, fish from the Bonnet Bay streams or Lake Oberon will be released into the dam once rehabilitation is complete. Regular monitoring trips will be conducted to observe the survival, behaviour and habitat use by these fish.

COSTS

YEAR 1

YEAR 2

YEAR 3

YEAR 4

YEAR 5

TOTAL

TOTAL

82.0

12.0

12.0

12.0

12.0

130.0

3.3.2 Swan galaxias

At present, nine translocated populations of Swan galaxias have been established. This number of populations meets the recovery criteria listed in the previous recovery plan for the species (Sanger 1993) and is sufficient to allow for eventual down listing of the species. However, the long term viability of the translocated populations must be proved prior to any formal attempts at down listing. To this end, the translocated populations will be monitored regularly throughout the life of this recovery plan. A small number of new translocations may be attempted if it is considered that some of the populations are unstable or too small.

Electrofishing surveys will be conducted and will consist of mark-recapture population estimates and collection of length frequency data. Two field trips per year will be required to complete this action.

COSTS

YEAR 1

YEAR 2

YEAR 3

YEAR 4

YEAR 5

TOTAL

TOTAL

3.0

3.0

3.0

3.0

3.0

15.0

3.3.3 Clarence galaxias

To achieve the recovery criteria outlined in this plan, at least five sites suitable for translocation of Clarence galaxias must be identified within or near the Clarence River catchment. Suitable sites must permanently carry water of good quality, must not contain brown trout or other fish species, must be reasonably accessible, and must not contain other threatened fauna.

Electrofishing surveys of the Clarence River and waters within or near its catchment will be conducted in the first year to determine the distribution of brown trout and other fish species. Samples of the invertebrate fauna of potential sites will be collected and sorted qualitatively to determine the presence of threatened species. Sites considered suitable for translocation will be identified to members of the recovery team and the PWS for approval prior to the transfer of fish. Once suitable sites have been identified and approved, approximately fifty adult fish collected from Clarence Lagoon will be released at each translocation site in the second year.

To ensure that translocated populations become established and remain viable, assessments of population size and structure will be carried out on a regular basis from the third year onwards. This will be achieved by conducting electrofishing surveys of all translocated populations.

Two field trips per year are required to complete this action.

COSTS

YEAR 1

YEAR 2

YEAR 3

YEAR 4

YEAR 5

TOTAL

TOTAL

2.0

1.0

2.0

2.0

2.0

9.0

3.3.4 Swamp galaxias

The survey of the distribution of fish species around Lake Pedder (Action 3.2.4) will provide the basis for the selection of translocation sites for the swamp galaxias. At least twenty populations, either natural or translocated, that are isolated from other fish species must be identified to achieve the criterion relating to this action. This requirement will dictate the number of translocations attempted.

Potential translocation sites must be reasonably accessible, isolated from introduced fish, hold water permanently and contain no other threatened fauna. Samples of invertebrates will be taken from potentially suitable sites and qualitatively analysed to determine the presence of any threatened species. Sites fulfilling all of the above criteria will be identified to the recovery team and the PWS for approval.

Once suitable translocation sites have been identified and approved, fish will be collected from larger natural populations and released. Approximately fifty adult fish will be introduced to each translocation site. Translocated populations will be monitored regularly to assess their ongoing viability and isolation from introduced species. Electrofishing surveys will be conducted to examine population size, structure and reproductive success.

Four field trips in the second year and two trips per year from the third year onwards will be required to complete this action.

COSTS

YEAR 1

YEAR 2

YEAR 3

YEAR 4

YEAR 5

TOTAL

TOTAL

-

4.0

2.0

2.0

2.0

10.0

3.3.5 Saddled galaxias

The potential role of translocations for the conservation of the saddled galaxias will be evaluated. As there are no large lakes within or near the Lake River catchment that do not contain introduced fish populations, the feasibility of using man-made dams in the catchment as habitats for translocated fish will be assessed. The outcomes of this assessment will be discussed with the relevant land managers and any resolutions or agreements regarding translocations will be pursued. No funds are required for this action at present.

3.4 Captive breeding trials

An initiative of this recovery plan is the introduction of a captive breeding program. The main aim of the captive breeding program is to produce a manual which outlines detailed methods for hatching and rearing threatened galaxiids in captivity. These methods will have application for the rearing and subsequent release of the five threatened galaxiids if this becomes necessary in the future. The methods are also likely to be directly applicable to a number of other threatened fish species and will provide an opportunity to conduct research regarding the reproduction and behaviour of galaxiid fishes in general.

A further aim of the captive breeding program is to involve the wider community in the recovery process. The need for maintenance of fish in aquaria provides an ideal situation for the involvement of volunteers. The development of good relations between the IFC and interested members of the public through programs such as this is seen as important to the long term success of recovery efforts for Tasmania's threatened galaxiids.

The captive breeding trials will run during the last four years of the recovery plan period.

COSTS

YEAR 1

YEAR 2

YEAR 3

YEAR 4

YEAR 5

TOTAL

TOTAL

22.0

9.0

9.0

9.0

9.0

58.0

3.5 Habitat management

A common approach to providing protection of habitat for the five species of threatened galaxiids will be adopted in this recovery plan. Under the Tasmanian Threatened Species Protection Act 1995, a provision exists for the determination of habitat deemed critical to the survival of threatened taxa. Such habitats are afforded legislative protection subject to the conditions of the Act. As part of the recovery plan, habitat deemed critical to the survival of the five threatened galaxiids will be identifed in consultation with the PWS and submitted for listing.

Other aspects of habitat management for the individual species are summarised in the following sections.

3.5.1 Pedder galaxias

In consultation with the IFC, the HEC has implemented new operating procedures for the Lake Pedder and Lake Gordon impoundments in an effort to minimise the risk of redfin colonisation of Lake Pedder. These procedures require the level of Lake Pedder to be kept at least 1 m above that of Lake Gordon before the radial gates on the canal linking the lakes are opened. By maintaining this difference in levels, the flow rate through the radial gates is estimated to be too swift to allow redfin to pass. The cost to the HEC in lost power generation capacity due to the maintenance of these operating procedures is estimated at up to $100 000 per year.

Control of the introduced fish species already present within Lake Pedder is not considered a feasible option for the conservation of the Pedder galaxias. Large populations of brown trout and climbing galaxias are well established in the lake and there is no effective method available for controlling these populations.

3.5.2 Swan galaxias

The habitats containing natural populations of Swan galaxias in the upper Swan River, Blue Tier Creek and Tater Garden Creek are managed as Wildlife Priority Areas by Forestry Tasmania. The management of these areas with regard to forestry practices involves minimizing stream sedimentation, allowing free movement of fish along the length of the streams, protecting streamside vegetation, protecting instream habitat and maintaining natural hydrological regimes.

All populations of Swan galaxias are situated above natural or man-made barriers to introduced fish. The integrity of these barriers requires regular monitoring. This will be incorporated in Action 3.2.2. If introduced species invade habitats containing populations of Swan galaxias, an assessment of the feasibility of their removal will be conducted. Any decision to attempt eradication of fish in such a situation must take scientific, logistic and social issues into account. If the recovery team agrees that eradication measures should proceed, this course of action will be pursued.

3.5.3 Clarence galaxias

Clarence Lagoon has been stocked with brook trout since 1963 and the Clarence galaxias has remained relatively abundant in the lagoon since that time. A series of recommendations regarding trout stocking policy at Clarence Lagoon were produced by the IFC in 1991 (Sanger and Fulton 1991). These recommendations affirmed the importance of continued stocking of Clarence Lagoon with brook trout to provide a relatively benign alternative to brown trout for the many anglers who fish this water. It was suggested that while a healthy and numerous brook trout population exists at Clarence Lagoon, the risk of illegal brown trout introductions by anglers is minimal.

It was also recommended that the trout free status of the Wentworth Hills lagoon be maintained and that brown trout be removed should they be illegally introduced to this water. For the Dyes Marsh and Dyes Rivulet populations, it was also recommended that the brown trout free status of these waters be maintained. This recovery plan supports these recommendations and strongly suggests that IFC policy continue to give the conservation of the Clarence galaxias highest priority when considering trout stocking issues within or near catchments where the Clarence galaxias occurs.

The lagoon containing a population of Clarence galaxias at Wentworth Hills is managed as a Wildlife Priority area by Forestry Tasmania with the specific recommendation that development of road access to the lagoon be prevented. This recommendation is intended to discourage the illegal introduction of brown trout into the lagoon.

As outlined in Action 3.3.3, a detailed electrofishing survey of the Clarence River and waters within and near its catchment will be conducted to determine the distribution of brown trout and other fish species. Using the results of this survey, any locations suitable for the installation of barriers to brown trout will be identified. Whilst the costs of barrier construction cannot be estimated at this stage, the IFC will attempt to utilise the resources and expertise of volunteers where possible for the construction of artificial barriers.

If brown trout invade habitats containing populations of Clarence galaxias, an assessment of the feasibility of trout removal will be conducted. Any decision to attempt eradication of trout in such a situation must take scientific, logistic and social issues into account. If the recovery team agrees that trout eradication measures should proceed, this course of action will be pursued.

3.5.4 Swamp galaxias

See habitat management measures for Lake Pedder (Action 3.5.1).

3.5.5 Saddled galaxias

A significant threat to the saddled galaxias in Woods Lake is degradation of habitat due to lake level fluctuations and nutrient rich inputs from the Ripple Creek diversion. The HEC has acknowledged the decline in water quality that occurred when the lake was drawn down in 1995 and the potential threat it posed to the saddled galaxias. Their swift response in releasing water from Arthurs Lake and subsequent discussions show that the HEC is willing to modify operating procedures at Woods Lake to take the requirements of the saddled galaxias into account. New operating guidelines were implemented for Woods Lake in late 1995 and the HEC has committed to their indefinite continuation. The IFC will continue to consult with the HEC regarding the habitat of the saddled galaxias and will seek to formalise the agreements that have been reached.

3.6 Public information and education

3.6.1 Threatened species education kit

The PWS has compiled an education kit for threatened Tasmanian fauna which has been distributed throughout Tasmania's schools. The kit contains information and activities regarding a wide variety of threatened fauna and currently includes a section on the Pedder galaxias. The format used in the education kit allows for the addition of further sections as they become available. Further pages on the other species of threatened galaxiids will be prepared and sent to schools for inclusion in the kit as part of this recovery plan. The page will be prepared by the PWS staff with input from the project officer.

COSTS

YEAR 1

YEAR 2

YEAR 3

YEAR 4

YEAR 5

TOTAL

TOTAL

0.3

0.3

0.3

0.3

0.3

1.5

3.6.2 Internet site

The PWS has established a site for threatened Tasmanian fauna on the Internet. Currently, there are pages on the Swan galaxias and Pedder galaxias which include general information, distribution maps and photographs of the two species. These pages will be updated and new pages for the Clarence, swamp and saddled galaxias will be prepared. The pages will be prepared and maintained by PWS staff with input from the project officer.

COSTS

YEAR 1

YEAR 2

YEAR 3

YEAR 4

YEAR 5

TOTAL

TOTAL

0.3

0.3

0.3

0.3

0.3

1.5

3.6.3 Threatened galaxiids brochure

A brochure including information about Tasmania's threatened galaxiids and threatening processes will be prepared. The aim of the brochure is to increase awareness of the diverse native fish fauna within Tasmania and the threats facing these fish. A particular target group for this action are trout anglers. The brochure will be distrbuted to anglers upon purchase of a fishing licence along with the IFC Fishing Code.

The brochures will outline the negative effects of illegal fish introductions and will highlight the need for a balance between a recreational trout fishery and the conservation of native fishes. Approximately 15 000 brochures will be distributed through fishing licence vendors and a further 5 000 will be distributed by other means.

COSTS

YEAR 1

YEAR 2

YEAR 3

YEAR 4

YEAR 5

TOTAL

TOTAL

4.0

-

-

-

-

4.0

3.6.4 Threatened galaxiids posters

A series of three posters depicting threatened Tasmanian galaxiids will be produced and distributed. The posters are aimed at reaching a wide variety of people rather than just those with a prior interest in fish or fishing. Approximately 600 copies of each poster will be produced and will be distributed to schools, councils, Waterwatch and Landcare groups, etc.

COSTS

YEAR 1

YEAR 2

YEAR 3

YEAR 4

YEAR 5

TOTAL

TOTAL

6.0

-

-

-

-

6.0

3.6.5 Portable interpretive display

An interpretive display will be produced to complement the brochure and posters. The display will be used for special events (eg. Agfest, IFC Open Day) and will therefore reach a wide audience. When not in use for such events, the display will be lent to schools, councils, etc.

COSTS

YEAR 1

YEAR 2

YEAR 3

YEAR 4

YEAR 5

TOTAL

TOTAL

3.3

-

-

-

-

3.3

Citation: Crook, D.A. and Sanger, A.C. (1997). Recovery Plan for the Pedder, Swan, Clarence, swamp and saddled galaxias. Inland Fisheries Commission, Hobart.

© Copyright to The Director, National Parks and Wildlife Service,

GPO Box 737, Canberra, Australian Capital Territory, 2061.

The views and opinions expressed in this report are those of the authors and do not necessarily reflect those of the Commonwealth Government, the Minister for the Environment and Heritage, or the Director of the Australian National Parks and Wildlife Service.

Apart from fair dealing for the purposes of private study, research, criticism or review as permitted under the Copyright Act, no part of this report may be reproduced by any means without the permission of The Director, National Parks and Wildlife Service.

Published by:

Inland Fisheries Commission
6b Lampton Ave
Derwent Park, Tasmania, 7009

Cover photographs: Ron Mawbey

Illustrations:

Carol Kroger (from 'Freshwater Fishes of Tasmania' by Wayne Fulton).