Printer Friendly

A general survey of the freshwater fish fauna of the Bomaderry Creek catchment in southern coastal New South Wales.


A field survey of the freshwater fishes of the Bomaderry Creek catchment in 1994-1995 recorded nine native species and one introduced species. One of the species recorded, Climbing Galaxias Galaxias brevipinnis, is of conservation concern in New South Wales. A report of an additional four native species was obtained from secondary sources. A concrete weir on Bomaderry Creek was found to represent a discontinuity in the distribution of some fish species. Four out of the six diadromous species recorded in the field survey were found only below the weir, while the two potamodromous species recorded were both found above and below the weir. The subsequent decommissioning of this weir in 1998 may substantially increase the potential habitat available for diadromous fish species in the Bomaderry Creek catchment. (The Victorian Naturalist 134 (4), 2017, 108-114)

Keywords: survey, New South Wales South Coast, Sydney Basin bioregion, freshwater fish, diadromous, potamodromous, weir barrier


The freshwater fish fauna of Australia has relatively low species diversity by global standards but is significant because of a high level of endemism (Allen et al. 2002; Leveque et al. 2008). River regulation and agricultural and urban development of catchments in south-eastern Australia have had a major impact on freshwater habitats and fish communities (Koehn and O'Connor 1990; Faragher and Harris 1994). Stream barriers such as dams and weirs can have a significantly adverse impact on freshwater fish populations, obstructing spawning and seasonal migrations and altering habitat conditions (Mallen-Cooper 1993; Morris et al. 2001; Gehrke et al. 2002; Rolls 2011). Government agencies and community groups have made a considerable effort in recent years to reverse some of the damage and to restore catchment connectivity and aquatic habitat values. Actions taken have included decommissioning of obsolete dams and weirs, construction of fishways specifically designed for Australian native fish, allocation of water for environmental river flows and restoration of riparian vegetation (Arthington and Pusey 2003; Bond and Lake 2003; Gilligan et al. 2003).

Bomaderry Creek, on the lower Shoalhaven River near Nowra on the south coast of New South Wales (NSW), is one of many coastal streams in south-eastern Australia modified by construction of a weir for local water resource development. This paper documents the results of a general survey of the freshwater fish fauna of the system prior to the decommissioning of this weir. Freshwater fishes are categorised in this paper as including estuarine species that often venture into freshwater, consistent with general references such as Allen (1989), McDowall (1996) and Allen et al. (2002).

Study area

Bomaderry Creek (34[degrees] 50.7' S, 150[degrees] 35.4' E) (Fig. 1 and see front cover) is located 125 km SSW of Sydney, in Dharawal Aboriginal Country in the Illawarra subregion of the Sydney Basin bioregion. The Bomaderry Creek catchment is about 36 [km.sup.2] in area, with an elevation range of 10-620 m (Australian Height Datum), and is a mix of farmland, forest and urban areas. The Bomaderry Creek system includes the upper tributaries Tapitallee Creek, Browns Creek and Good Dog Creek. The lowest part of the creek is estuarine (Fig. 2). In 1938, a concrete weir (Fig. 3) was constructed on Bomaderry Creek about 5.3 km above its confluence with the Shoal-haven River to provide a reliable water supply for the township of Bomaderry (NSW Office of Environment and Heritage 2016). Approximately 21 km of stream occurs above the weir.



The primary survey method involved wading along streams at night with a spotlight and a hand-held fine mesh dip-net. Larger fish were identified by sight while smaller species were captured for identification and then released. Species were identified by reference to Allen (1989). Surveys were done on nine nights between April 1994 and August 1995 (Appendix 1). The majority of surveying was done along the section of creek within about 1 km upstream and downstream of the weir (sites 4 to 7) (Appendix 2). This part of the creek is within the Bomaderry Creek Bushland, an urban bushland area situated between North Nowra and Bomaderry (Barratt 1994; NSW Office of Environment and Heritage 2016). Additional sites were sampled lower (sites 1 to 3) and higher (sites 8 to 12) in the catchment (Fig. 1 and Appendix 2). The author also accompanied NSW Fisheries officers surveying the lower 6 km of the creek on one afternoon and night in August 1995. The methods employed comprised electrofishing (sites 4, 5 and 7) and use of minnow traps and gill nets (sites 1, 5 and 6). Of particular interest was site 1 on the estuarine section of the creek, where the stream was too deep to sample effectively by wading. Assessment of the local status of species in the Bomaderry Creek system was based on the number of sites where species were recorded and the relative abundance of species at a site. Categories used were rare, uncommon and common.


Seven species of freshwater fish (six native and one introduced) were recorded in the Bomaderry Creek catchment by the spotlight/dip-net wading survey method (Table 1). Two species (Australian Bass Macquaria novemaculeata and Striped Gudgeon Gobiomorphus australis) were found only downstream of the weir, and one species (Climbing Galaxias Galaxias brevipinnis) was found only in the headwaters of the catchment (at an elevation of about 200 m AHD). One additional native freshwater species (Bullrout Notesthes robusta) was recorded by NSW Fisheries officers in the deeper estuarine section of Bomaderry Creek. It was captured in gill nets together with several estuarine species, of which two (Striped Mullet Mugil cephalus and Flat-tail Mullet Liza argentea) are also listed here as they can often be found in the lower freshwater reaches of coastal rivers. Overall, the field survey recorded nine freshwater fish species below the weir and five above the weir (Table 1 and Appendix 3).



Bomaderry Creek has a relatively diverse native freshwater fish community considering its small size, and the apparent absence of additional introduced species such as Carp Cyprinus carpio and Goldfish Carassius auratus at the time of the survey is also noteworthy. The nine native species reported here comprise about 43% of the native freshwater fish species known from the Shoalhaven River downstream of Tallowa Dam (Bishop and Bell 1978; Gehrke et al. 2002; Murphy unpublished data) and about 29% of the species known from the south coast of NSW (Faragher and Harris 1994). Further survey effort in Bomaderry Creek, particularly in the estuarine section, would be likely to identify additional species. Barratt (2015) reported an additional four species from the lower (Bomaderry Creek Bushland and estuary) sections of the creek: Estuary Perch Macquaria colonorum, Freshwater Mullet Myxus petardi, Yellow-eyed Mullet Aldrichetta forsteri and Flat-headed Gudgeon Philypnodon grandiceps. Southern Blue-eye Pseudomugil signifer has been recorded in the Shoalhaven River 15 km upriver from Bomaderry Creek at the mouth of Bengalee Creek (Murphy pers. obs. Feb 1995). Other possible species include Short-headed Lamprey Mordacia mordax, Short-finned Eel Anguilla australis, Common Jollytail Galaxias maculatus and Empire Gudgeon Hypseleotris compressa.

Climbing Galaxias has been identified as a species of conservation concern in NSW (Morris et al. 2001), although it has not been formally listed as a threatened species under the NSW Fisheries Management Act 1994 (current to June 2017). The distribution of this species is considered likely to have been fragmented as a result of forest clearing and predation by introduced trout (McDowall and Fulton 1996). The forest-shaded headwater stream where it was recorded in the present study is typical of the species' habitat (O'Connor and Koehn 1998). An ecologist residing in the local area has noted that Climbing Galaxias has not been seen at this site or in the local area since about 2000 and may now be locally extinct (G Daly pers. comm. October 2016).

The results of this survey suggest that the weir represented a discontinuity in the distribution of some fish species in the Bomaderry Creek system. Variation between species distributions was in part a reflection of differences in life-history habits. The two potamodromous (migrating wholly within freshwater) species recorded in the field survey, Australian Smelt Retropinna semoni and Cox's Gudgeon Gobiomorphus coxii, were evidently able to maintain populations above the weir. In contrast, only two of the six diadromous (migrating between freshwater and the sea) species recorded were found above the weir (Table 1). A diadromous life history includes catadromous species (species that migrate from freshwater to the sea as adults to spawn, e.g. Long-finned Eel Anguilla reinhardtii and Australian Bass) and amphidromous species (species that live and spawn in freshwater with the hatchlings being swept downstream to the sea before returning to freshwater, e.g. Climbing Galaxias), as well as anadromous species (species that migrate from the sea to freshwater as adults to spawn--nil recorded in this study). Dams and weirs have been found to affect populations of diadromous fish species more than potamodromous species (Gehrke et al. 2002; Rolls 2011). Three of the four native species recorded above the Bomaderry Creek weir are known for their ability to climb vertical obstacles such as waterfalls and the damp walls of dams and weirs: the potamodromous Cox's Gudgeon (Bishop and Bell 1978; Larson and Hoese 1996) and the diadromous Long-finned Eel (Bishop and Bell 1978) and Climbing Galaxias (McDowall and Fulton 1996; O'Connor and Koehn 1998).


The Bomaderry weir was occasionally overtopped during extremely high stream flows (Murphy pers. obs.) but was usually a barrier to fish movement. The weir was obsolete by the early 1970s and in 1998 (three years after this survey) a section was removed to restore natural stream flows (NSW Office of Environment and Heritage 2016) (Fig. 4). The decommissioning of the weir has provided opportunity for additional diadromous fish species such as Bullrout, Australian Bass and Striped Gudgeon to recolonise Bomaderry Creek above the weir. The information documented here provides a useful benchmark of the composition and distribution of the freshwater fish community of Bomaderry Creek in the mid-1990s when the weir was still in place, and will be of value in any future assessment of the catchment area's freshwater fish community.



This research was done under a scientific research permit issued by NSW Fisheries. Thanks to Sam Murphy for company in the field in 1994-1995 and 2016, Alan Lugg for inviting the author to accompany the Fisheries survey and allowing the results to be included in this paper, Terry Barratt for information from his plan of management, Garry Daly for access to his property at the headwaters of Tapitallee Creek and for information on the local status of Climbing Galaxias, Jess Murphy for help preparing Fig. 1 and an anonymous reviewer whose suggestions improved the paper.


Allen GR (1989) Freshwater fishes of Australia. (TFH Publications: Neptune City, USA)

Allen GR, Midgley SH and Allen M (2002) Field guide to the freshwater fishes of Australia. (Western Australian Museum: Perth, Western Australia)

Arthington AH and Pusey BJ (2003) Flow restoration and protection in Australian rivers. River Research and Applications 19, 377-395.

Barratt T (1994) Bomaderry Creek Bushland Draft Plan of Management. (Australian Conservation Foundation, Nowra, NSW)

Barratt T (2015) Fish species in Bomaderry Creek Bushland. Available online at:

Bishop KA and Bell JD (1978) Observations on the fish fauna below Tallowa Dam (Shoalhaven River, New South Wales) during river flow stoppages. Australian Journal of Marine and Freshwater Research 29, 543-549.

Bond NR and Lake S (2003) Local habitat restoration in streams: constraints on the effectiveness of restoration for stream biota. Ecological Restoration and Management 4, 193-198.

Faragher RA and Harris JH (1994) The historical and current status of freshwater fish in New South Wales. Australian Zoologist 29, 166-176.

Gehrke PC, Gilligan DM and Barwick M (2002) Changes in fish communities of the Shoalhaven River 20 years after construction of Tallowa Dam, Australia. River Research and Applications 18, 265-286.

Gilligan DM, Harris JH and Mallen-Cooper M (2003) Monitoring changes in Crawford River fish community following replacement of an ineffective fishway with a vertical-slot fishway design: results of an eight year monitoring program. NSW Fisheries Final Report Series No. 45. NSW Fisheries, Narrandera, NSW.

Koehn JD and O'Connor WG (1990) Threats to Victorian native freshwater fish. The Victorian Naturalist 107, 5-12.

Larson HK and Hoese DF (1996) Gudgeons. In Freshwater fishes of South-Eastern Australia (2nd edition), Chapter 34. Ed R McDowall. (Reed Books: Sydney, NSW)

Leveque C, Oberdorff T, Paugy D, Stiassny MLJ and Tedesco PA (2008) Global diversity of fish (Pisces) in freshwater. Hydrobiologia 595, 545-567.

Mallen-Cooper M (1993) Habitat changes and declines of freshwater fish in Australia: what is the evidence and do we need more? In Sustainable Fisheries through Sustaining Fish Habitats, pp. 118-123. Ed DA Hancock. Australian Society for Fish Biology Workshop. Bureau of Rural Resource Sciences Proceedings. (Australian Government Publishing Service: Canberra)

McDowall R (Ed) (1996) Freshwater fishes of South-Eastern Australia (2nd edition). (Reed Books: Sydney, NSW)

McDowall RM and Fulton W (1996) Galaxiids. In Freshwater fishes of South-Eastern Australia (2nd edition), Chapter 10. Ed R McDowall. (Reed Books: Sydney, NSW)

Morris SA, Pollard DA, Gehrke PC and Pogonoski JJ (2001) Threatened and potentially threatened freshwater fishes of Coastal New South Wales and the Murray-Darling Basin. NSW Fisheries Final Report Series No. 33. NSW Fisheries, Sydney, NSW.

NSW Office of Environment and Heritage (2016) Bomaderry Creek Regional Park Plan of Management. Office of Environment and Heritage, Sydney, NSW.

O'Connor JD and Koehn JD (1998) Spawning of the broad-finned galaxias Galaxias brevipinnis Gunther (Pisces: Galaxiidae) in coastal streams of southeastern Australia. Ecology of Freshwater Fish 7, 95-100.

Rolls RJ (2011) The role of life-history and location of barriers to migration in the spatial distribution and conservation of fish assemblages in a coastal river system. Biological Conservation 144, 339-349.

Received 1 December 2016; accepted 8 June 2017
Appendix 1. Survey dates for 1994-1995 Bomaderry Creek fish survey.

14 April1994                               Sites 2, 3
08 September1994                           Sites 5, 6
10 September1994                           Sites 3, 5, 6, 7
14 September 994                           Site 12
15 September1994                           Sites 1, 4, 5, 6
03 June1995                                Sites 8, 9, 10
11 June1995                                Sites 5, 6, 7, 11
15 July 1995                               Site 8
31 August1995                              Sites 1, 4, 5, 6, 7

Appendix 2. Location of 1994-1995 survey sites.
Sites are numbered by increasing distance from Shoalhaven River (see
Fig. 1).

 1             ZLions Park boat ramp, Bolong Rd, Bomaderry
 2             ZSporting field, Bolong Rd, Bomaderry
               Z(shallowly inundated at time)
 3             ZFrog Hollow wetland, Bolong Rd Bomaderry
 4             ZMossy Gully, Bomaderry Creek Bushland
 5             ZPool below weir, Bomaderry Creek Bushland
 6             ZPool above weir, Bomaderry Creek Bushland
 7             ZEnd of West Cambewarra Rd,
               ZBomaderry Creek Bushland
 8             ZHockeys Lane crossing, Tapitallee Creek
 9             ZMain Rd crossing, Good Dog Creek
10             Tapitallee Rd crossing, Tapitallee Creek
11             Browns Mountain Rd crossing, Tapitallee Creek
12             Private property on Flannery Rd, Tapitallee Creek

 1             34[degrees] 51.42' S, 150[degrees] 36.46' E
 2             34[degrees] 51.42' S, 150[degrees] 36.37' E
 3             34[degrees] 51.55' S, 150[degrees] 36.08' E
 4             34[degrees] 50.84' S, 150[degrees] 35.45' E
 5             34[degrees] 50.70' S, 150[degrees] 35.38' E
 6             34[degrees] 50.68' S, 150[degrees] 35.39' E
 7             34[degrees] 50.49' S, 150[degrees] 35.24' E
 8             34[degrees] 50.24' S, 150[degrees] 33.69' E
 9             34[degrees] 49.40' S, 150[degrees] 33.71' E
10             34[degrees] 49.50' S, 150[degrees] 32.48' E
11             34[degrees] 49.39' S, 150[degrees] 31.34' E
12             34[degrees] 49.07' S, 150[degrees] 30.44' E

Appendix 3. Freshwater species recorded at each of 12 sites in
Bomaderry Creek catchment 1994-1995. Sites 1-5 were below the weir and
sites 6-12 above the weir.

Species                              Site number
                    1    2   3   4   5   6   7   8   9   10   11   12

Long-finned Eel                      x   x   x   x   x        x
Climbing Galaxias                                                  x
Australian Smelt                 x   x   x   x   x       x
Eastern Gambusia         x                   x   x
Bullrout            x
Australian Bass                      x
Striped Mullet      x
Flat-tail Mullet    x
Cox's Gudgeon                    x   x   x   x   x       x
Striped Gudgeon              x
Total               3    1   1   2   4   3   4   4   1   2    1    1

Ninety Years Ago


About 30 members and friends attended the excursion to the Fish Hatcheries--at Studley, Park, under the leadership of Mr. F. Lewis, Chief Inspector of Fisheries and Game, on the afternoon of Saturday, September 10th. After giving a short explanation of the methods of hatching the eggs of Rainbow and Brown Trout, Mr. Lewis conducted the party through one of the hatcheries, where the eggs of these fishes were in process of being hatched. The ova were in various stages of development. The leader showed us through another hatchery, where the most modern apparatus for the propagation of fish has been installed, with the object of hatching native fishes, such as Murray Cod, Perch, and Blackfish. Success, it is confidently expected, will be ultimately achieved. The ponds in which many of the more mature fishes are kept were inspected. A vote of thanks was tendered to Mr. Lewis.--L. L. HODGSON.

From The Victorian Naturalist XLIV p 169, October 5, 1927

Michael J Murphy

'Blackbird Grange', 2 Rundle Street, Coonabarabran, NSW 2357
Table 1. Freshwater fishes of the Bomaderry Creek catchment 1994-1995.
(*) Introduced species. # Estuarine species extending into freshwater.

Family               Scientific name               Common name

Anguillidae          Anguilla reinhardtii          Long-finned Eel
Galaxiidae           Galaxias brevipinnis          Climbing Galaxias
Retropinnidae        Retropinna semoni             Australian Smelt
Poeciliidae          Gambusia holbrooki (*)        Eastern Gambusia
Scorpaenidae         Notesthes robusta             Bullrout
Percichthyidae       Macquaria                     Australian Bass
Mugilidae            Mugil cephalus #              Striped Mullet
                     Liza argentea #               Flat-tail Mullet
Eleotridae           Gobiomorphus coxii            Cox's Gudgeon
                     Gobiomorphus                  Striped Gudgeon

Family               Local status                  Life history

Anguillidae          Common above and              Diadromous
                     uncommon below weir           (Catadromous)
Galaxiidae           Rare above weir               Diadromous
                     (headwaters)                  (Amphidromous)
Retropinnidae        Common above and              Potamodromous
                     below weir
Poeciliidae          Uncommon above and            Unspecified
                     below weir
Scorpaenidae         Rare below weir (estuary)     Diadromous
Percichthyidae       Uncommon below weir           Diadromous
Mugilidae            Rare below weir (estuary)     Diadromous
                     Rare below weir (estuary)     Unspecified
Eleotridae           Common above and              Potamodromous
                     below weir
                     Rare below weir               Diadromous
COPYRIGHT 2017 The Field Naturalists Club of Victoria Inc.
No portion of this article can be reproduced without the express written permission from the copyright holder.
Copyright 2017 Gale, Cengage Learning. All rights reserved.

Article Details
Printer friendly Cite/link Email Feedback
Title Annotation:Contributions
Author:Murphy, Michael J.
Publication:The Victorian Naturalist
Article Type:Report
Geographic Code:8AUNS
Date:Aug 1, 2017
Previous Article:Notes on a record of the White-footed Dunnart Sminthopsis leucopus (Gray, 1842) (Dasyuromorphia: Dasyuridae) north of Nowra, New South Wales.
Next Article:Behaviour of Daddy Long-legs spiders Pholcus phalangioides at Notting Hill, Victoria.

Terms of use | Privacy policy | Copyright © 2019 Farlex, Inc. | Feedback | For webmasters