Category Archives: Species spotlight

Candidates for second most interesting Australian freshwater fish.

FykeNetSet

Spang, Leioptherapon unicolor (Günther, 1859)

Image: Fyke netting (Courtesy of Oliver Scholz)

 

Written by: Iain ‘Listy’ Ellis

‘Listy, pen me something quirky for themorayslair’ I was asked….apparently it’s a place on the web to share thoughts and experiences with fellow fish nerds. Crikey, that’s dangerous…. I think to myself… #quirky and #something to do with fish and #Listyboy…this could bring back a whole raft of suppressed memories. By the way, Listyboy – that’s me. Ebb named me that in my first month working as a techo in the strange but alluring world of freshwater ecology out Mildura way. That was back in 1998, but like a Carp to sweetcorn, the nick-name stuck. I used to tick off items for field trips on lists before we set off into the empty. I still work out here where the Murray and Darling rivers meet (give or take a couple of hundred river miles in any direction).

But I digress – he wants a fishy article.

A ‘Species spotlight’ perhaps? Although I spend a lot of time working with the threatened Murray hardyhead (a freshwater fish that – get this – prefers salty water!), I choose the Spangled perch as my favourite. Although it is one of Australia’s most widespread fish, on the eastern side of the country, it’s rarely detected as far south as Menindee on the Darling River. In fact, according to the texts, prior to 2010 there had only been four records of it from the Murray River, and three of those were after the famous monster flood of 1956. Apparently it’s a bit cold down here for them in winter and as they are rarely detected far south of “the Menindee line”, therefore I shouldn’t really know much about Spangs.

I’d heard stories of course. Spangs are tough and live in rivers, lakes, ponds, puddles, tanks, wet wheel ruts and pretty much any wet-spot across the top half of Australia (e.g. Unmack 2001, Kerezsy et al. 2013). They can move quickly from/between said wet-spots at the smell of rain just to reach another waterhole before any of their mates. Okay, so I embellish a little – they generally wait for the rain to fall, but they are pretty amazing none the less. Until recently some folks still believed they could aestivate (survive dry spells cocooned in the dirt) as they turned up in water that seemed unreachable. We now know they don’t aestivate, although, they can jump from a tank, slap their way down a 20 meter hallway before almost succumbing to desiccation in a dusty corner after half an hour. I know this because I saw it happen – the same fish, several times. We called him Jumpy-slappy, and yes he survived exposure for half an hour in the dust, and recovered when replaced in his tank. Spangs are even reported to be transferred about the place as “rains of fishes”, whereby swirling eddies of desert wind siphon them out of one wet patch and drop them elsewhere.

I felt myself lucky to glimpse a couple of little Spangs in the northern Menindee Lakes back in the1990’s, flushed down the Darling River to our waiting nets in a small flood. I was with Ebner actually– the same trip a freak storm created a six-metre swell, shipwrecking me and Ebb on the distant side of a pretty remote lake. My life flashed before my eyes back then. Not because of the storm, but because we had skipped lunch, and I could see Ebb weighing up the value of hunting for a raw Carp, or gnawing one of my spindly arms – if only he could find a decent rock in the sand dunes with which to dispatch me humanely (and in adherence to our animal ethics permit).

But I digress again…

Yep, I thought those two scrawny Spangs might be the last I’d ever see, along with the lone Hyrtl’s catfish Ebb excitedly pulled from a net that same week (still the only one recoded down these parts by the way!). Clearly, I wasn’t eaten, but I didn’t see another Spang for almost two decades. Not until 2010 in fact. We got a flood. Not a massive one, but significant given the preceding decade of drought. By now I had a bit of a feel for fish in my part of the world, and I hoped like billy-oh we might stumble across a Spang or two when the flood waters reached the lower Darling, and eventually the Murray River at Wentworth.

Hyrtls&Spangler

That Hyrtl’s catfish, and a pretty little Spang

And we did! Little Chip (Danielle, a smashing young fisho I’ve had the pleasure of working with the last 5 years or so) returned smiling from monitoring surveys south of Menindee, rewarding my prayers with news of not just a couple, but loads of Spangs in the flood waters. In a world where small fish like gudgeons or smelt almost always dominate our catch, Chip returned hauls for the next couple of years in which Spangs were frequently the dominant fish!. But they weren’t just in the lower Darling. We got Spangs in the Murray River from down near the river mouth (the Coorong in SA) up as far as the Hattah Lakes near Euston. It was becoming clear what salty northern fishos like Hairy Balcombe and Adam “the red-eyed-blue-arse” Kersxkzfgy meant when they said Spangs had “strong dispersal capabilities” (see. Kerezsy et al. 2013). We saw first hand how they fearlessly navigate shallow drains or pipes and swim up slippery hills and along rainy roads during rain events – to reach a puddle ahead of their mates.

ListyBlackBoxBijiji

A full Lake Bijiji in 1997

What still amazes me though is the fact Spangs still hang around down here south of the Menindee Line –two years after the floods have subsided. That’s why they are my favourite fish. They make me rethink what I thought I knew.

 

References & further reading

Kerezsy, A., Balcombe, S. R, Tischler, M., and Arthington, A. H. (2013). Fish movement strategies in an ephemeral river in the Simpson Desert, Australia. Australian Journal of Ecology 60, 45–57.

Llewellyn, L. C. (1973). Spawning, development, and temperature tolerance of the spangled perch, Madigania unicolor (Gunther), from inland waters in Australia. Australian Journal of Freshwater and Marine Research 24, 73-94.

Unmack, P. J. (2001). Fish persistence and fluvial geomorphology in central Australia. Journal of Arid Environments 49, 653-659.

http://www.desertfishes.org/australia/fish/leiounic.shtml

2SpBlackieBroadhurstArticle

Two-spined blackfish, Gadopsis bispinosus

An adult Two-spined blackfish with “giraffe-like” patterning

 

By Ben Broadhurst

Institute for Applied Ecology, University of Canberra

My favourite freshwater fish species would have to be the Two-spined blackfish or “blackies” as they are known to those who work on them (I’ve studied them for over a decade, so we are on a nickname basis). The Two-spined blackfish is a medium sized member of the Percichthyidae family (freshwater basses and cods) endemic to the Murray-Darling Basin in south-eastern Australia. This species primarily inhabits cool upland rivers and streams where it prefers shelter provided by spaces between cobbles and boulders. This species grows to a maximum of around 350 mm total length, though individuals over 250 mm are uncommon. This species is usually abundant where it is present though has a highly disconnected distribution with many populations now fragmented from each other. This species is highly susceptible to sedimentation and is a common prey item of alien trout species.

BroadhurstCotterRiver2SpBlackieArticle

Typical Two-spined blackfish habitat, a cobble / boulder-bottomed upland stream (Photo: Ben Broadhurst)

Two-spined blackfish are a highly charismatic freshwater fish, manoeuvring largely with their pectoral fins in and out of structure, much like clown fishes do in anemones on coral reefs. An outstanding feature of the Two-spined blackfish is their marbled, almost giraffe-like, patterning of dark greens and yellows, more prevalent in some individuals than others. During some aquaria-based trials we have conducted on radio-tag retention of Two-spined blackfish, my colleagues and I noted that they became tame and boisterous very quickly and would feed from the hand within a week or so of being captured. Whilst snorkelling in rivers where this species is present, I’ve found them to be quite inquisitive, with my presence acknowledged; but they usually do not attempt to escape or take shelter.

Two-spined blackfish spawn in late-spring to early summer. Although natural egg locations are difficult to locate, it is hypothesised that this species deposits it sticky eggs onto a hard, sediment free surface. After spawning the male take responsibility for guarding and fanning the eggs (and larvae) to keep them oxygenated and free from sediment. Some experimental studies have had success with spawning Two-spined blackfish in PVC tubes.

I’ve had the pleasure of studying the movement patterns of this species using radio-telemetry in both riverine and reservoir environments. My research has shown that this species is nocturnally active and returns back to its home rock or piece of timber each morning after foraging on aquatic insects throughout the night. In rivers, Two-spined blackfish generally exhibit small home ranges of around 15 – 30 m, generally completing a day’s movements within the same pool. In reservoirs, Two-spined blackfish can move more than 500 m in a night, moving to feeding grounds at dusk then returning to their daytime shelters at dawn.

BlackieAnaesthesia

An Adult two-spined blackfish being gently anaesthetized prior to radio-tag insertion

 

Further reading:

Koehn, J. D. (1990). Distribution and conservation status of the two-spined blackfish Gadopsis bispinosus in Victoria. Proceedings of the Royal Society of Victoria 102, 97-103.

Jackson, P. D., Koehn, J. D., Lintermans, M. & Sanger, A. C. (1996). Family Gadopsidae: Freshwater blackfishes. In Freshwater fishes of south-eastern Australia (McDowall, R. M., ed.), pp. 186-190. Australia: Reed Books.

Lintermans, M. (1998). The ecology of the two-spined blackfish Gadopsis bispinosus (Pisces: Gadopsidae). Unpublished M. Sc. Thesis. p. 219. Canberra: School of Botany and Zoology, Australian National University.

O’Connor, J. P. & Zampatti, B. P. (2006). Spawning season and site location of Gadopsis bispinosus Sanger (Pisces: Gadopsidae) in a montane stream of southeastern Australia. Transactions of the Royal Society of South Australia 130, 227-232.

Broadhurst, B. T., Lintermans, M., Thiem, J. D., Ebner, B. C., Wright, D. W. & Clear, R. C. (2012). Spatial ecology and habitat use of two-spined blackfish Gadopsis bispinosus in an upland reservoir. Aquatic Ecology 46, 297-309.

Broadhurst, B., Dyer, J., Ebner, B., Thiem, J. & Pridmore, P. (2011). Response of two-spined blackfish Gadopsis bispinosus to short-term flow fluctuations in an upland Australian stream. Hydrobiologia 673, 63-77.

BenBroadhurst

Ben Broadhurst is a scientist at the University of Canberra. He specialises in studying the ecology of inland freshwater fishes and is a keen angler.

[email protected]

https://www.researchgate.net/profile/Ben_Broadhurst

ScalelessGoby

Abracadabra, the Scaleless goby

By Brendan Ebner

In my experience the Scaleless goby attains a maximum total length of about 50 mm. It lives in coastal streams of the Wet Tropics in flowing water (typically 0.2-0.4 ms-1, Donaldson et al. 2013) often in laminar surface flow (Pusey et al. 2004) in very specific habitat. Snorkelling is a great way to appreciate colonies of this goby in shallow runs. By moving your hands slowly over the benthos, individuals will spook from subsurface haunts and interstitial spaces. If you approach the run very slowly from the downstream side and wait patiently, individuals will sometimes swim by and interact with one another, seemingly without being scared of the massive snorkeler. On some occasions the sands will literally shift to reveal the once buried goby as if by a magician’s sleight of hand. The Scaleless goby can re-bury just as quickly or dart off for a distance of up to a couple of metres with a startling bound of acceleration resembling that of a Mexican jumping bean. The female is somewhat drab and has a smaller head and mouth than the male. The male is cloaked in a skin that defies accurate description. But here goes nothing. It is orange in places, intermixed with green and white camouflage patches. There is a smattering of light blue-whitish fluorescent spots over much of the body. It is also somewhat bug-eyed, and has a distinctive scissor shaped pattern on the caudal peduncle. The male opens an enlarged grotto of a mouth, revealing a bright orange gob that serves as a signal to neighbouring ladies (see photo). They make fascinating pets but do best in a small aquarium with at least two power heads to create benthic turbulence, and require daily feeding to maintain body condition. There is still much to learn about the Scaleless goby, which has several similarly poorly known congeners found in streams of the tropical Pacific (e.g. Keith et al. 2013).

 

Donaldson, J. A., Ebner, B. C. & Fulton, C. J. (2013). Flow velocity underpins microhabitat selectivity in amphidromous gobies of the Australian Wet Tropics. Freshwater Biology 58, 1038–1051.

Keith P., Marquet G., Gerbeaux, P., Vigneux, E. Lord, C. (2013). Poissons et crustacés d’eau douce de Polynésie. Taxonomie, écologie, biologie et gestion. Société Franchcaise d’ Ichyologie, Paris. 282 pages.

Pusey B. J., Kennard M. J. & Arthington A. H. (2004). Freshwater Fishes of North-EasternAustralia. CSIRO Publishing, Melbourne, 702 pp.

Congolli

The Congolli, Pseudaphritis urvillii

By Chris Bice

Written 17 December 2013, Posted April 2014

The Congolli as it is known in South Australia (or Tupong if you’re from Victoria or Sandy if you’re Tasmanian), is a small-medium sized fish (up to about 350 mm) native to coastal streams of south eastern Australia (McDowall 1996). Body colouring can vary between individuals and habitats, but it is typically light brown with dark brown blotches or bars on the sides and dorsal surface, and white on the ventral surface. A benthic species, the Congolli has a flattened head with a pair of high set eyes and a large mouth. It also doesn’t have a swim bladder like most other ray-finned fishes. The Congolli is an ambush predator, commonly burying itself in the substrate with just its eyes protruding, before bursting out and preying upon unsuspecting small fish, crustaceans and aquatic insects.

The Congolli is a catadromous species meaning it resides in freshwater habitats as an adult, but spawns in the ocean. As such, the ability of adults to migrate from freshwater to marine habitats to spawn and then for juveniles to migrate upstream into freshwater habitats is fundamental for the persistence of populations of this species. Subsequently, barriers to migration in the form of barrages, weirs, culverts, etc. represent a significant threat to this species throughout its range.

Interestingly, Congolli display marked sexual dimorphism. All fish over 200 mm are invariably mature females, whilst male size maxes out at only 150 mm. Furthermore, there appears to be sexual segregation in habitat use with mature females most common in freshwater habitats and the smaller males more common in brackish and estuarine habitats. In the Lower Lakes of the River Murray, adult females migrate downstream to meet up with the males and spawn in winter (Zampatti et al. 2011).

When they decide to migrate, their desire for a rendezvous with the males is surprisingly strong – one female, tagged with an acoustic transmitter, was observed to migrate downstream a distance of 35 km in one night; not a bad effort for a small fish that doesn’t have a swim bladder! Studies on the movement of female Congolli in both South Australia and Victoria (Crook et al. 2010) did not detect return movements of adult female Congolli from the ocean, suggesting the species is semelparous – that is the adult females die after spawning.

Congolli were much more abundant throughout their range prior to the damming and regulation of south eastern Australia’s coastal rivers. Indeed they once comprised a significant proportion of the commercial fishery in the Lower Lakes and Coorong in South Australia, and were commonly used as live bait by the same commercial fishers when targeting mulloway at the Murray Mouth (Evans 1991). Nonetheless, increased knowledge of the life-history of Congolli has highlighted key issues (notably connectivity between riverine and marine environments to allow migrations) to be addressed by environmental managers to ensure the conservation of this unique species.

 

Bice

Chris Bice is a fish ecologist based in Adelaide, South Australia. Chris’s areas of expertise include threatened species ecology, fish movement and the response of fish to altered flow regimes.

http://www.sardi.sa.gov.au/__data/assets/pdf_file/0005/126626/Bice_Chris.pdf

 

References

Crook, D. A., W. M. Koster, J. I. Macdonald, S. J. Nicol, C. A. Belcher, D. R. Dawson, D. J. O’Mahony, D. Lovett, A. Walker and L. Bannam (2010). Catadromous migrations by female tupong (Pseudaphritis urvillii) in coastal streams in Victoria, Australia. Marine and Freshwater Research 61: 474-483.

Evans, D. (1991). The Coorong. A multi-species fishery. Part 2. Fishing Methods, Technology and Personal Experiences 1930-1966 and Gear Statistics 1972-1989, Fish Research Paper, Department of Fisheries South Australia. McDowall, R. M., Ed. (1996). Freshwater fishes of south-eastern Australia. Sydney, Reed.

Zampatti, B. P., C. M. Bice and P. R. Jennings (2011). Movements of female Congolli (pseudaphritis urvillii) in the Coorong and Lower Lakes of the River Murray South Australian Research and Development Institute (Aquatic Sciences), Adelaide. SARDI Publication No. F2011/000333-1. SARDI Research Report Series No. 577. 32pp.

 

Hey Ebb, Tough question, I suppose they are one of my favourite fish species for a few reasons, firstly they aren’t particularly common (it’s easier to like the species that are a little more rare), secondly, I find the catadromous life-history pretty interesting and last, whilst physically they are very tough fish – you can directly transfer them between freshwater and marine water and vice versa with apparently no impact, and they seem more or less impervious to handling – they are highly vulnerable to the impacts of river regulation due to their migratory life history.   Sounds pretty artsy, but I think it’s this contrast between ‘toughness’ and vulnerability that makes them appealing.   Feel free to incorporate this however you like  

Cheers Chris  

 

Editor’s note: I think your email says it just fine.

Pmaraena-profile-Koster-Dec-2013-Figure-2

The Australian Grayling (Prototroctes maraena)

By Wayne Koster

18 December 2013

Why I really like this species – I like the smell of cucumbers, nah just kidding. I really like the Australian grayling because they can be such an elusive fish and their ecology has long puzzled researchers, starting with the work of Allport and Saville-Kent way back in the late 1800′s.

Pmaraena-profile-Koster-Dec-2013-Figure-1

The Australian grayling is a nationally threatened amphidromous fish species that inhabits coastal streams in south-eastern Australia (Crook et al 2006). The species has a strong cucumber odour and grows to a length of about 300 mm.

The New Zealand grayling (Prototroctes oxyrhynchus), the only other member of the genus, appears to be extinct (McDowall 1976). For many years, the spawning and movement behaviours of adult Australian grayling remained a mystery. However, recent research using novel approaches (egg/larval surveys combined with acoustic telemetry) has provided some important insights. In particular, adult Australian grayling have been shown to undertake large (e.g. 30 km) downstream spawning migrations to the lower reaches of rivers in autumn coinciding with increases in river flow (Koster et al. 2013). This downstream spawning migration strategy appears to be relatively rare among the amphidromous fishes. Interestingly, following downstream migration, adult Australian grayling also tend to migrate back upstream to the same area they previously occupied. The Australian grayling can be a difficult-to-find species at times. In smaller, clear rivers a useful technique, especially on sunny days, can be to walk or drive along the river bank and polaroid for schools of fish. The Australian grayling sometimes displays surface activity, especially in the early morning, which can also be a useful technique for locating fish. The migratory behaviours of juvenile Australian grayling, including the importance of river flow as an upstream migration cue, are poorly understood and is an important area for future research. The Australian grayling is a delicate species and does not tolerate handling well.

References
Allport, M. (1870). No title. Monthly Notices of Papers and Proceedings of the Royal Society of Tasmania for 1869 6.

Crook, D. A., Macdonald, J. I., O’Connor, J. P. and Barry, B. (2006). Use of otolith chemistry to examine patterns of diadromy in the threatened Australian grayling Prototroctes maraena. Journal of Fish Biology 69, 1330–1344.

Koster, W.M., Dawson, D.R. and Crook, D.A. (2013). Downstream spawning migration by the amphidromous Australian grayling (Prototroctes maraena) in a coastal river in south-eastern Australia. Marine and Freshwater Research 64, 31–41.

McDowall, R.M. (1976). Fishes of the family Prototroctidae (Salmoniformes). Marine and Freshwater Research 27, 641–659.

Saville-Kent, W. (1885). Fisheries Department. Report for the year terminating 31st July, 1885. Tasmanian Parliamentary Paper No. 90.