Indicator: IW-28 Number of effective fishways

Data

Queensland

Fishways have been built in Queensland since the early 1990s. Earlier fishways were built using northern hemisphere type designs that did not cater for Queensland fish species and were mainly developed with salmon and trout in mind; fish that migrate upstream as adults and have exceptional swimming abilities.

The number of fishways currently constructed on Queensland rivers is 46. Of these, 24 are considered effective or likely to be effective, 9 are partially effective or likely to be partially effective and the rest are ineffective or of unknown effectiveness.

There are any number of causeways in coastal Queensland that act as low level crossings but have now been replaced by high level bridges. These continue to act as barriers to fish migration. Local governments tend to leave them in place and rely on floods to 'remove' these structures.

Source: Environmental Protection Agency - Queensland (unpubl.) 2001, Volume of effluent discharged to non-tidal waterbodies, Qld, 2001, Dr Laurence Knight Environmental Reporting Unit Environmental Protection Agency PO Box 15155, CITY EAST, Qld, 4002 Ph 07 3227 8956, Fax 07 3220 3542 Email laurence.knight@epa.qld.gov.au.

NSW

Of the 53 native freshwater species in NSW, 28 undertake large-scale migrations, 16 migrate on local scales and the status of the remaining 9 species is unknown. At present in NSW there are over 4300 physical barriers and 28 fishways effective for native fish.

Source: NSW Fisheries 2003, Status of Fisheries Resources 2001-2002, NSW Fisheries, Cronulla, NSW, viewed 15 Nov 2005, http://www.fisheries.nsw.gov.au/science/scientific_outputs.

Fish species found at the Branch River Crossing, NSW, illustrates the impact of weirs
Common Name	Above Weir	Below Weir
Port Jackson glassfish	0	237
Long-finned eel	5	11
Silver bellies/biddies	0	83
Hypseleotris gudgeons	7	5
Flat-tailed mullet	0	28
Australian bass	13	49
Bully/Sea mullet	6	10
Freshwater mullet	2	1
Flat-head gudgeon	71	148
Dwarf flathead gudgeon	3	1
Blue eye	0	49

Source: World Wildlife Foundation Australia 2003, Redundant weir removal: the Branch River Crossing - A case study, WWF Australia, Sydney, viewed 8 Dec 2005, http://www.fisheries.nsw.gov.au/_data/assets/pdf_file/4919/Weir-Removal-Case-Study.pdf.

Balranald Weir report: summary of total fish catches from sites downstream (D) and upstream (U) of Balranald Weir showing sites and seasons sampled. Catches are pooled results from both years sampled.
Species name	Autunm		Winter		Spring		Summer
	D	U	D	U	D	U	D	U
Native
Silver perch	7	3	0	6	1	1	9	18
Flyspecked hardyhead	3	0	5	3	10	0	3	0
Western carp gudgeon	5	9	1	2	32	34	86	28
Murray cod	8	7	13	1	3	1	1	2
Golden perch	14	45	36	66	7	11	10	29
Crimson-spotted rainbowfish	82	41	47	306	22	4	660	54
Bony bream	988	807	525	1450	7	13	756	288
Flatheaded gudgeon	0	0	0	0	0	0	1	0
Australian smelt	999	129	626	1581	70	9	388	295
Introduced
Common carp	45	70	56	136	24	37	455	46
Goldfish	9	15	3	39	5	2	91	53
Mosquitofish	0	3	0	1	0	0	0	1
Redfin perch	14	23	1	9	9	2	134	9

Source: Baumgartner, L.J, 2004, The effects of Balranald Weir on spatial and temporal distributions of lower Murrumbidgee River fish assemblages, NSW Department of Primary Industries-Fisheries, viewed 14 Nov 2005, http://www.fisheries.nsw.gov.au/_data/assets/pdf_file/5241/
Output_477_Baumgartner_Balranald_Weir_Final_Report_PDF.pdf.

What the data mean

In the studies reported, small fish species were found immediately downstream of weirs, despite previously being considered non-migratory. This suggests that fishways should be designed to allow passage for small individuals and species and not just for the adults of large species.

Seasonal changes are important; the greatest upstream movement in fish appears to be summer and autumn.

In Queensland and NSW, there seems to be an increasing acceptance that fishways suited to native species are beneficial and efforts are underway to construct more and to remove obstructions such as weirs. Data have not been found for other jurisdictions.

Data Limitations

The number of fishways in other jurisdictions is unknown

Issues for which this is an indicator and why

Inland Waters - Habitat scale influences - Fish passage

Number of effective fishways would be indicative of improvements in the management of inland waters.