in stream

Australia New Guinea Fishes Association Queensland Inc.

IN STREAM Volume 14 (Number 3) June 2005

CONTENTS Club News Mary River - Queensland Common Names of Australia Fish Amphidromous Gobies Fish Eating Bats Caragobius rubristriatus ANGFA Convention Report Growing Rainbowfishes in Ponds

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IN STREAM Volume 14 Issue 3 - June 2005 ISSN 1446-3830

Editor

Adrian Tappin (07) 3348 7491 [email protected] This publication may not, in part or in whole, be copied, reproduced, translated or reduced to any electronic medium without the permission of ANGFA Queensland. While the publishers have taken all responsible efforts to ensure the accuracy of material contained in this publication, the publisher accepts no responsibility or liability for any lose or damage which may result from an inaccuracy or omission, or from the use of information contained in the publication. The authority for statements and claims made in In-Stream is the responsibility of the contributors. Reference to named products or technologies does not imply endorsement by the publisher. Opinions expressed in the publication are not necessarily those of ANGFA Qld. The deadline for editorial copy is July 15, 2005. Contact the Editor for details. Alternatives are: E-mail to [email protected] or snail mail to 5 Atlanta Street Manly Queensland 4179 Australia Hard copy text should be accompanied by floppy disc or CD in a common word processing program. Text and Illustrations may be submitted electronically with prior arrangement with the editor.

Membership/Subscription Jeff Gunston (07) 3886 9347 [email protected]

In-Stream is published six times a year by Australia New Guinea Fishes Association Queensland Inc. A subscription to In-Stream (six issues) is $30.00 per year in Australia and $35.00 outside of Australia. Send cheque or credit card details to The Treasurer, PO Box 8135, Woolloongabba Qld 4102, Australia. or subscribe on our website at : http://www.angfaqld.org.au An electronic version (PDF) in colour, is available for members and can be downloaded from the ‘Members’ area on our web site.

Meetings

ANGFA Qld meets on the second Friday of every second month from February: Bar Jai Hall 178 Alexandra Road Clayfield, Brisbane Meetings commence at 8.00 pm

EDiTORiAL Welcome to the June issue of In-Stream. We have somewhat of a mixed bag for you in this issue. Our “Get-Away” this month is to the Mary River in Queensland. The Mary River catchment covers an area of approximately 9700 km2, and is located in the south-east corner of Queensland. The Mary River flows approximately 370 km downstream from its headwaters in the Conondale Range near Maleny through Gympie, Tiaro and Maryborough, then changes course to northeast entering Hervey Bay at River Heads, west of Fraser Island. Also in this issue is an interesting article from Geoff McPherson and Simon Robson about the fish-eating bats in Australia. We also have a look at some Amphidromous gobies and an unusual rare goby called Caragobius rubristriatus. We also take a sneak preview of the proposed common names of Australian freshwater fishes. Bruce Hansen gives us a roundup of this years ANGFA convention that was held in Melbourne. Bruce is a regular attendee of ANGFA convention and his summaries are something everyone looks forward too. Finally we have an in-depth look at growing rainbowfishes in pond for all you members out there breeding all those wonderful rainbowfish. In the next issue we will take a look at the river systems of the Gulf of Carpentaria. There is a very large gap in our knowledge of what fish species are present in the Gulf streams. Many rivers in the Gulf region have not been adequately surveyed for fish and only minor surveys have occurred in some catchments. However, there are some that have had no surveys at all. They just waiting for some intrepid ANGFA members to go and take a look. Something to consider for your next field trip. We will also hear from our foreign correspondent in Kiunga. All this and more – just like “Big Kev” I’m Excited

Adrian Tappin

‘I took in February three table spoons of mud from three different points, beneath the water, on the edge of a little pond; this mud when it was dry weighed only 6 3/4 ounces; I kept it covered up in my study for six months, pulling up and counting each plant as it grew; the plants were of many kinds, and were altogether 537 in number; and yet the viscid mud was all contained in a breakfast cup!’ Charles Darwin on the Origin of Species 1859

COVER PHOTO: Blackwood River, Western Australia

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CLUB NEWS Doug Collom - Secretary Phone: (07) 3277 7171 Email: [email protected] April Meeting The feature talk for the evening was on keeping native fish in Brisbane in winter, largely without heaters. This went into the cold blooded fish’s digestion in cooler water, much less need to feed, and watching for stress. Unheated tanks in Brisbane get down to about 15-16°C, which can be readily tolerated by most native species. The use of timers where heaters had to be used for very tropical fish was also discussed. A technical hitch to another talk on ponds then had Greg Ure speaking more about fish tank temperature control from a talk he had given elsewhere, and had on his lap top. There was another good auction to end the night with many less often seen species on offer. June 10 Meeting Greg Ure will have returned from the Singapore Aquarama, with photos and tales. We will get the pond show from last meeting running this time. We are hoping that quite a few speakers from research establishments will be ready to talk to us also as the year progresses. We have some more of those interesting fish coming from Bruce Sambell’s Ausyfish for the auction again. Swap Meet Saturday July 9 [2 pm - 5 pm] As mentioned in the last In-Stream, we will be having a mid winter ‘dry feet’ outing in July at our normal meeting place, the Bar Jai Hall. We invite all members to come along, bring any of the bits and pieces of fish keeping and collecting gear you don’t use any more. Bring fish, plants, whatever you like. You can swap, barter or give away as you wish. We may also have some demonstrating of some techniques. We’ll have a sausage sizzle starting at 4.30 pm. Come along, even if it’s just for a yarn with other native fish enthusiasts. This swap meet is members only. Aquarium Shops Supporting ANGFA. You will notice at the back of In-Stream, a growing list of Aquarium trade shops supporting ANGFA by giving our members discounts. If an aquarium shop which you deal with is not on the list yet, have a talk to them about the opportunities for them to attract business from ANGFA members. If they offer a discount to our members we will list them for no cost in our magazine. We have also supplies of ANGFA business cards which you can take to give the shopkeepers to hand to any interested non ANGFA customers. Presentations at Meetings. As stated above, we hope to have some interesting speakers from research organisations able to present talks to meetings again soon. I can vouch for the fact that Microsoft PowerPoint, which we use to develop many of our

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The care and breeding of aquarium fishes is by no means a static, unchanging hobby. Aquarists are continually discovering new facts about the fishes they keep and share their experiences with others. It is this kind of information exchange among hobbyists that keeps the hobby always fresh and exciting. The Editorial team seek to be a part of that excitement by examining both new and established areas of interest to members. We welcome contributions, suggestions and/or criticism from our readers. All aquarists can benefit from communication, and we hope that In-Stream will help increase interaction among our members. Our success in this area depends primarily on you. So please write and tell us your opinions or submit articles for publication. They will help us to make In-Stream a better newsletter.

presentations these days, makes putting together last minute talks a much simpler task. But it wouldn’t happen without the generous support of the key fish photographers in ANGFA, Gunther Schmida and Neil Armstrong, who have given us use of some of their best slides for illustrating our printed articles and in preparing talks for club meetings. So if any of you have a topic which you could talk about at our meetings, but feel you lack the pretty pictures to illustrate your talk, have a talk to me and we’ll see what we can do to give you the right stuff. I’ll do the PowerPoint development too if you give me the information to go in it. Don’t forget the Swap Meet July 9. See you there.

Lab evaluations of 7 native fresh and euryhaline fish species, selected as possible mosquito control agents, show that Crimson spotted Rainbowfish (Melanotaenia duboulayi), Australian Smelt (Retropinna semoni), Firetail Gudgeon (Hypseleotris galii), Fly-specked Hardyhead (Craterocephalus stercusmuscarum) and Pacific Blue-eye (Pseudomugil signifer) are the most effective predators of Culex annulirostris larvae. The Crimson-spotted Rainbowfish and the Firetail gudgeon are the most common local species and are amenable to transport and aquaculture. These two species have been selected for use in field trials assessing the efficacy of integrated control methods. The Crimson spotted Rainbowfish has also been selected for evaluation of a predator avoidance response in ovipositing female mosquitoes. Bulletin of the Ecological Society of Australia 33:2 (June 2003)

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Mary River Queensland

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he Mary River catchment covers an area of approximately 9700 km2, and is located in the south-east corner of Queensland. The Mary River flows approximately 370 km downstream from its headwaters in the Conondale Range near Maleny through Gympie, Tiaro and Maryborough, then changes course to north-east entering Hervey Bay at River Heads, west of Fraser Island. From its headwaters in the Conondale ranges the river drops from 500 m above sea level to 200 m in the first five kilometres, at an average bed gradient of 6%. From this point down to Conondale the bed gradient is 0.62% with the gradient reducing as it moves towards the coast. Between Conondale and Kenilworth it averages 0.17% with a gentle slope of 0.04% down to the tidal barrage at Tiaro. Within the catchment are a number of storages and weirs that provide both irrigation and urban water supplies. Rainfall (and therefore river flow) is seasonally variable, with most of the rain falling between January and April. The Tagigan, Beenham, Wapunga and Blackall Ranges form the eastern watershed. The western watershed is formed by the Kandanga, Amamoor and Coast Ranges. Mount Langley (868 m) in the Conondale Range is the highest peak in the catchment. The Mary River catchment has 2947 km of waterways including several major tributaries; Obi Obi, Yabba, Little Yabba, Six Mile, Amamoor, Kandanga, Tinana, Deep, Munna and Wide Bay Creeks. These tributaries provide

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habitat for a diverse range of flora and fauna some of which has been identified as rare, vulnerable and endangered under the Nature Conservation Wildlife Act. The waterways provide the last remaining habitat for the endangered Mary River Cod (Maccullochella peelii mariensis) and Mary River Turtle (Elusor macrurus). The rivers and streams in the catchment vary considerably in terms of their natural character. The Mary River and its major western tributaries are moderate to high energy sand and gravel bed streams. They typically have large high flow channels that can accommodate flows of substantial size. Floodplains and river terraces occur in the wider parts of the valleys. The character of the major eastern tributaries of the Mary River is quite different. Obi Obi Creek rises near Maleny then plunges steeply through a deep bedrock gorge before flowing through floodplain deposits and joining the Mary River. Six Mile Creek is a low-energy rainforest stream, with a sandy substrate and extensive deposits of large woody debris. Tinana Creek is a wallum stream, with distinctive natural water quality, flora and fauna. Early explorers to the region record lush floodplains with many waterholes, but today few of these remain in the landscape. Remnant floodplain wetlands in the larger catchments of the region are uncommon and are typically associated with paperbark (Melaleuca quiquenervia) woodland and forests. Melaleuca wetlands have been extensively cleared for urban development and sugar cane production and many of the shallower seasonal water bodies have been drained or have been silted up.

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History

Fish Species

The Mary River catchment has a unique and interesting history that dates back to the early Portuguese explorers of the 16th century. Portuguese charts of eastern Australia published in 1536 included what is believed to be Fraser Island. Dutch clay pipes have also been discovered in middens on Fraser Island, which also suggests Dutch contact with the Aborigines in the 17th century. The first recorded Europeans to sight the region were the crew of the Endeavour in 1770. Other naval explorers included Lieutenant Matthew Flinders in 1797 and 1802, and William Edwardson who in 1822 sailed through the Great Sandy Strait and established that the Great Sandy Peninsular was in fact an island.

Approximately forty-one species of fish that either breed or spend a major portion of their life cycle in freshwater are thought to occur in the Mary River. An additional five or six native species have been translocated, primarily for recreational fishing purposes. Four exotic species have been introduced into the Mary River system.

In May of 1842 Andrew Petrie and a small crew sailed for three days up the Mary River, or Monoboola as it was then known, a distance of 80 km as far as Tiaro. Here they could go no further. Petrie named the stream the Wide Bay River and it was known by this name until 1847 when Governor Fitzroy decided that the river should be called Mary in honour of his wife, Lady Mary Fitzroy. Thus the lower Mary was explored and settled. The upper and lower Mary River regions were under pastoral occupation by the late 1840s. Runs were initially established for wool production, with Maryborough being the port for export of this product. As pastoralists settled in the upper Mary River the locality soon became known for its timber wealth, and the dense rainforests were soon being exploited. Timber was transported down the river to where it could be used or exported. Gold was discovered by James Nash in Gympie in 1867 and all the watercourses from there to Jimna in the upper catchment were worked by prospectors. The Mary River today is the result of the cumulative impacts of these land use changes and those that followed.

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The Mary River catchment supports three fish species of conservation significance including two endangered fish species (Maccullochella peelii mariensis and Nannoperca oxleyana), and the Queensland lungfish (Neoceratodus forsteri). The Mary River is the last river to support natural populations of the Mary River cod and also contains a unique mainland population of Nannoperca oxleyana. Nannoperca oxleyana inhabit soft water wallum streams and swamps. In the Mary River catchment they occur in Tinana Creek. Populations of lungfish in the Mary River are in considerably better condition than in the Burnett River, the only other river within its natural range. The Mary River catchment is at an interzone between southern temperate coastal freshwater fish species (e.g. Australian bass, Australian smelt, short-finned eel, striped gudgeon) and northern tropical freshwater species (e.g. barramundi, mangrove jack, Rendahl's catfish, jungle perch, barred grunter). It also contains some endemic groups either restricted to the Mary River region or restricted to sub-tropical Queensland and northern New South Wales (e. g. Mary River cod, Australian Lungfish, Oxleyan pygmy perch, freshwater mullet, Duboulay's rainbowfish and the silverstreak hardyhead) as well as species with a wide distribution in eastern Australia (e.g. purple spotted gudgeon, Tandanus catfish, bully mullet, long-finned eel). Therefore the diversity of freshwater fishes in the region is high by Australian standards.

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Mary River Catchment

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Fish Species List Ambassis agassizii - Agassiz's glassfish Ambassis marianus - Estuary glassfish Anguilla australis - Southern shortfin eel Anguilla reinhardtii - Longfin eel Arius graeffei - Blue catfish Arrhamphus sclerolepis krefftii - Snub-nosed garfish Bidyanus bidyanus - Silver perch (translocated) Craterocephalus marjoriae - Silverstreak hardyhead Craterocephalus fulvus - Tawny hardyhead Glossamia aprion - Mouth almighty Gobiomorphus australis - Striped gudgeon Hypseleotris compressa - Empire gudgeon Hypseleotris galii - Firetail gudgeon Hypseleotris klunzingeri - Western carp gudgeon Hypseleotris sp. - Midgley’s carp gudgeon Kuhlia rupestris- Jungle perch Lates calcarifer – Barramundi Leiopotherapon unicolor - Spangled perch Maccullochella peelii mariensis - Mary River cod Macquaria ambigua - Golden perch (translocated) Macquaria novemaculeata - Australian bass (translocated?) Melanotaenia duboulayi - Duboulay’s rainbowfish Megalops cyprinoides - Oxeye herring Mogurnda adspersa - Southern purple-spotted gudgeon Mugil cephalus - Sea mullet Myxus petardi - Freshwater mullet Nannoperca oxleyana - Oxleyan pygmy perch Nematalosa erebi - Bony bream Neoceratodus forsteri - Lungfish Neosilurus hyrtlii - Hyrtl’s catfish Notesthes robusta – Bullrout Ophiocara porocephala- Spangled gudgeon Ophisternon gutturale - Swamp eel Ophisternon sp. - Swamp eel (undescribed) Oxyeleotris lineolata – Sleepy cod (translocated) Philypnodon grandiceps - Flathead gudgeon Philypnodon sp. - Dwarf flathead gudgeon Porochilus rendahli - Rendahl’s catfish Pseudomugil signifer - Southern blue-eye Redigobius bikolanus - Speckled goby Retropinna semoni - Australian smelt Rhadinocentrus ornatus - Ornate rainbowfish Scleropages leichardti – Southern saratoga (translocated) Tandanus tandanus - Freshwater catfish Introduced Exotic Species Gambusia holbrooki - Eastern Gambusia Poecilia reticulata - Guppy Xiphophorus helleri - Swordtail Xiphophorus maculatus – Platy The effects of introduced fishes in the Mary River system are unknown. Estuarine or marine species that occasionally penetrate into the freshwater reaches Diadromous species (eg Myxus petardi, Mugil cephalus, Lates calcarifer, Lutjanus argentimaculatus, Megalops cyprinoides, Macquaria novemaculeata, Anguilla

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reinhardtii) have regular-predictable migrations between freshwater and marine/estuarine environments to complete their life history. Some of these species penetrate upstream to the headwaters and may spend many years in freshwater. Migrations may be for breeding, growth, maturation or a combination of these. Barriers to migration and degraded estuarine and freshwater habitats can all have impacts on these species. Only two diadromous species (Arius graeffei and Arrhamphus sclerolepis krefftii) are known to be able to complete their entire lifecycle in freshwater if access to the estuary or sea is blocked. Some marine-estuarine species use freshwater on a regular or seasonal basis e.g. Gerres filamentosus, Acanthopagrus australis and Selenotoca multifasciata). Some species such as Acanthopagrus australis may move more than 40 km up into freshwater. Estuaries are also used by juveniles of Lates calcarifer, Lutjanus argentimaculatus, Megalops cyprinoides, Scatophagus argus, Selenotoca multifasciata, Pseudomugil signifer and Mugil cephalus; all species that move between fresh and estuarine waters. Acanthopagrus australis - Yellowfin bream Afurcagobius (Favonigobius) – Goby Caranx sexfasciatus - Big-eye trevally Carcharhinus leucas - Bull shark Chanos chanos – Milkfish Elops hawaiensis - Giant herring Gerres filamentosus - Threadfin silver biddy Liza dussmieri - Flat-tailed mullet Liza subviridis - Green-back mullet Lutjanus argentimaculatus - Mangrove jack Monodactylus argenteus - Diamond fish Platycephalus fuscus - Dusky flathead Plectorhinchus gibbosus - Harry hotlips Polydactylus macrochir - Threadfin Salmon Scatophagus argus - Spotted scat Selenotoca multifasciata - Striped scat Translocation Australian fishes that have been translocated into the Mary River system include the golden perch (Macquaria ambigua), silver perch (Bidyanus bidyanus) saratoga (Scleropages leichardtii) and Sleepy cod (Oxyeleotris lineolata). Some translocated species have only been recorded recently in the region e.g. sooty grunter (Hephaestus fuliginosus) and barcoo grunter (Scortum barcoo) in the Mary system. It is not yet known if there are established populations of these species or only isolated occurrences resulting from either deliberate or accidental unauthorised introductions. The impact of these translocations on other species in the region is not yet known. The Australian bass (Macquaria novemaculeata) is of uncertain origin but may have been translocated to the catchment. It has become more abundant in upstream reaches following stocking.

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There are reports that Murray cod have been introduced into the Mary system on several occasions. An article from the Maryborough Chronicle, dated 4.6.1870, outlined a proposal to introduce Murray cod into the Maryborough Water Reservoir. Whether this occurred is not clear. Murray cod from the Condamine River were reportedly introduced into the Mary system at Obi Obi Creek in 1880. The cod were said to have been brought overland in milk churns, although the Kenilworth Historical Society point out that no dairying was carried out in the district until the 1890s and the likelihood of cod surviving such a long trip is low. Also, it is unclear why such an introduction would be attempted given the reported abundance of Mary River cod. Perhaps it was because Murray cod grow larger. More recently, Murray cod are reported to have been released in the Mary River in the 1970's. However, although Murray cod were introduced into the Mary, they can no longer be found there. Reproduction and Spawning The reproduction and spawning requirements of freshwater fish occurring in the catchment area are not well understood. Small-bodied species (e.g. Craterocephalus marjoriae, Melanotaenia duboulayi, Pseudomugil signifer, Hypseleotris spp. and Mogurnda adspersa) are generally thought to have extended breeding seasons from spring through to summer (September-January) but spawning often appears to be concentrated in September and October. Retropinna semoni appears to spawn slightly earlier in the year, commencing in late winter. For many of these small-bodied species, the spawning stimulus is unknown but usually corresponds with increasing water temperatures and photoperiod. Spawning

cues are probably not associated with rising water levels or flooding. However, for some species (e.g. Hypseleotris klunzingeri) spawning can occur during inundation of shallow backwaters and marginal vegetation. In general, the peak spawning period for many of the smallbodied species coincides with pre-flood periods of low and relatively stable discharge in rivers of south-east Queensland rivers. However, breeding may also continue through the months of elevated discharge at the commencement of the wet season (December/January). Multiple spawning over an extended period may be an adaptation to the relatively unpredictable timing of the onset of wet season flooding. The spawning strategy of most of the small-bodied species involves the deposition of adhesive, demersal eggs on a range of submerged physical structures, including gravel and cobble substrates, woody debris, root masses, aquatic vegetation and submerged marginal (riparian) vegetation. Rapid fluctuations in water levels resulting from river regulation may be potentially deleterious to species that spawn in shallow marginal habitats and submerged bankside structures such as root masses and riparian vegetation as the eggs of most species are probably intolerant of desiccation. Although relatively little is known of the habitat requirements of the larvae of many fish species, available evidence indicates that larval Pseudomugil signifer, Melanotaenia duboulayi, Craterocephalus marjoriae and Hypseleotris spp. prefer shallow marginal habitats.

Maccullochella peelii mariensis (Mary River cod) - Günther Schmida

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Mary River Habitat - Günther Schmida

Little Yabba Creek - Bruce Hansen

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Aponogeton elongatus subsp. elongatus (Yabby Creek) - Günther Schmida

Aquatic & Wetland Plants Aquatic plant surveys have been conducted in the Mary River. Myriophyllum verrucosum, Vallisneria nana and Potamogeton crispus were the most widespread species occurring in about one-third of sites sampled. Myriophyllum verrucosum and Vallisneria nana contributed over half (53.8%) of total mean submerged macrophyte cover. One rare and threatened species (Aponogeton elongatus subsp. elongatus) was recorded from Teebar Creek. The outcomes of these surveys are listed below. The temperature tolerances of aquatic macrophytes found in the Mary River are poorly known. In northern hemisphere freshwater systems, aquatic macrophytes may die off during winter and persist as underground tubers or dormant turions. However, some taxa (e.g. Potamogeton crispus) are capable of continued growth in southeast Queensland during winter. Aquatic plant surveys have found no relationships between the abundance of submerged macrophytes and stream temperature in southeast Queensland streams. Aquatic plants known to occur in the Mary River Catchment Note * = introduced (naturalised) species Ageratum spp. - Billygoat weed* [Damp areas] Alternanthera denticulata - Lesser joyweed [Damp areas, stream banks] Alternanthera nana - Hairy joyweed [Stream banks] Amaranthus hybridus - Wild amaranth

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Aponogeton elongatus subsp. elongatus – Laceplant [Still waters] Azolla filiculoides - Pacific azolla [Still-slow flowing waters] Azolla pinnata - Ferny Azolla [Still- slow flowing waters] Bacopa monnieri - Bacopa [Stream margins] Bolboschoenus caldwellii - Caldwell's clubrush [Stream margins] Bolboschoenus fluviatilis - Marsh clubrush [Stream margins, brackish waters] Brachiaria foliosa - Leafy panic Brachiaria mutica - Para grass* [Still-slow flowing waters] Cabomba caroliniana - Fanwort* [Still-slow flowing waters] Callitriche sp. – Starwort Callitriche stagnalis - Starwort Callitriche muelleri – Starwort [Shallow waters, damp ground] Carex spp. [Creek banks] Carex appressa - Tall sedge [Creek banks, damp places] Carex fascicularis - Tassel sedge [Creek banks] Centella asiatica - Pennywort [Damp areas] Ceratophyllum demersum – Hornwort [Still-slow flowing waters] Chara spp. - Stonewort Chloris gayana - Rhodes grass* Cladium procerum - Leafy twigrush [Marshes, damp areas] Cynodon nlemfuensis var. nlemfuensis - African stargrass* [Moist areas near stream margins] Cyperus aquatilis [Damp areas] Cyperus brevifolius - Mullumbimby couch* [Damp areas]

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Cyperus compressus* [Damp areas] Cyperus difformis - Rice sedge [Damp areas] Cyperus distans - Piedmont sedge [Damp areas] Cyperus enervis [Damp areas] Cyperus equisetina [Damp areas] Cyperus eragrostis - Umbrella sedge* [Stream margins, damp places] Cyperus exaltatus - Tall flatsedge [Damp areas] Cyperus flavidus [Swampy or damp areas] Cyperus gracilis - Slender sedge [Damp places] Cyperus haspan var. haspan [Damp areas] Cyperus involucratus - Umbrella sedge* [Damp areas] Cyperus iria - Variable sedge [Damp areas] Cyperus laevis [Damp areas] Cyperus lucidus - Tall cutty grass [Stream banks, swamps] Cyperus nutans var. eleusinoides [Damp areas] Cyperus pilosus - Fuzzy sedge [Stream banks, swamps, damp areas] Cyperus polystachyos - Manyspike sedge, Bunchy sedge [Stream/river margins] Cyperus polystachyos var. polystachyos - Bunchy sedge [Stream/river margins] Cyperus scariosus [Brackish waters] Cyperus sculptus [Damp places] Cyperus sesquiflorus - Kyllinga weed* [Damp areas] Cyperus tenuiculmis [Damp areas] Cyperus trinervis - Australian sedge [Damp areas] Cyperus vaginatus - Stiff flat-sedge [Damp areas] Dactyloctenium aegyptium - Egyptian grass* Dichanthium annulatum - Angleton grass Echinochloa colona - Awnless barnyard grass* [Shallow water, damp areas] Echinochloa crus-galli - Barnyard grass* [Shallow water, damp areas] Echinochloa dietrichiana [Stream and swamp margins] Echinochloa telmatophila - Swamp barnyard grass [Stream and swamp margins] Echinopogon ovatus var. ovatus - Forest hedgehog grass [Damp areas] Eclipta prostrata - White Eclipta* [Damp ground] Egeria densa - Dense waterweed* [Still-moderately flowing waters] Eichhornia crassipes - Water hyacinth* [Still-slow flowing waters] Elatine gratioloides – Waterwort [Shallow water, damp ground] Eleocharis cylindrostachyos – Spikerush Eleocharis dietrichiana – Spikerush Eleocharis philippinensis – Spikerush [Damp areas] Eleocharis sphacelata - Tall spikerush [Damp areas] Enteropogon unispiceus Eriocaulon australe [Swampy areas] Eriocaulon nanum [Swampy areas] Eryngium expansum - Queensland eryngo* [Damp areas] Fimbristylis aestivalis - Summer fringerush Fimbristylis dichotoma - Common fringerush Fimbristylis ferruginea – Fringerush Fimbristylis polytrichoides – Fringerush [Swampy areas] Fimbristylis tristachya – Fringerush Gahnia aspera – Sawsedge Gahnia clarkei - Tall sawsedge [Swampy areas]

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Hydrilla verticillata – Hydrilla [Still and flowing waters] Hydrocotyle tripartite - Pennywort [Damp areas] Hygrophila angustifolia - Temple plant Ischaemum australe var. australe - Large bluegrass [Damp soils] Ischaemum fragile – [Damp sandy soils] Isolepis sp. - Club rush [Stream margins] Isolepis inundata - Swamp club rush [Stream margins, swamps] Juncus spp. Juncus bufonius - Toad rush [Damp areas] Juncus continuus [Damp areas] Juncus polyanthemus - Striated rush [Damp areas] Juncus prismatocarpus - Branching rush [Damp areas] Juncus usitatus - Common rush [Shallow waters] Juncus validus - Roundhead rush Lachnagrostis filiformis – Blowngrass [Damp areas] Lemna disperma - Duckweed [Slow flowing waters] Lepidosperma longitudinale - Pithy swordsedge [Swampy areas] Lepironia articulata - Tube sedge [Creek, river banks] Leptochloa decipiens subsp. decipiens - Slender canegrass [Stream banks] Leptochloa decipiens subsp. peacockii - Slender canegrass [Stream banks] Leptochloa panicea subsp. brachiata Lobelia sp. [Damp areas] Lomandra spp. – Matrush [Stream, river banks] Lomandra hystrix – Matrush [Stream, river banks] Lomandra longifolia – Longleaf matrush [Stream, river banks] Ludwigia octovalvis - Willow primrose [Damp ground] Ludwigia peploides subsp. montevidensis - Water primrose [Stream, river edges, or upright on damp ground] Ludwigia peruviana - Peruvian primrose* [Shallow-deep waters] Lythrum salicaria - Purple loosestrife [Shallow waters, damp ground] Marsilea sp. – Nardoo [Shallow waters, damp ground] Melinis repens - Natal grass* Microlaena stipoides var. stipoides - Weeping grass [Damp areas] Monochoria cyanea – Bog hyacinth [Shallow still-slow flowing waters] Muehlenbeckia gracillima [Stream margins] Myriophyllum simulans – [Still-slow flowing waters, damp ground] Myriophyllum variifolium – varied water-milfoil [Still-slow flowing waters, damp ground] Myriophyllum verrucosum - Red water-milfoil [Still-fast flowing waters, damp ground] Najas tenuifolia - Water nymph [Still-slow flowing waters] Nitella spp. - Stonewort Nymphaea gigantea var. gigantea - Giant waterlily [Still waters] Nymphaea violacea - Native waterlily [Still-slow flowing waters] Nymphoides crenata - Wavy marshwort [Permanent stillslow flowing waters] Nymphoides indica – Water snowflake [Fresh water to 3.5m deep]

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Oenothera indecora subsp. bonariensis - Small flower evening primrose* Oplismenus undulatifolius var. mollis - wavyleaf basketgrass Ottelia alismoides – Ottelia [Still and flowing waters] Ottelia ovalifolia - Swamp lily [Still-fast flowing waters] Ottochloa nodosa Panicum bisulcatum - Blackseed panic [Stream margins] Panicum maximum* Panicum maximum var. maximum - Guinea grass* Panicum maximum var. coloratum* Paspalidium aversum [Damp ground] Paspalum conjugatum - Sourgrass* Paspalum distichum - Water couch [Damp ground, stream margins] Paspalum longifolium [Damp areas] Paspalum notatum - Bahia grass* Paspalum scrobiculatum - Ditch millet [Damp areas] Pennisetum alopecuroides - Swamp foxtail [Damp ground, stream margins] Persicaria attenuata - Water pepper [Shallow waters, damp ground] Persicaria decipiens - Slender knotweed [Shallow water, damp ground] Persicaria hydropiper - Water pepper [Shallow water, damp ground] Persicaria lapathifolia - Pale knotweed* [Creek, river margins; damp ground] Persicaria orientalis [Shallow water, damp ground] Phalaris aquatica - Toowoomba canary grass* Philydrum languinosum – Frogmouth [Damp ground, shallow waters] Phragmites australis - Common reed [Stream, river margins] Poa labillardieri var. labillardieri - Tussock grass [Stream banks] Polygonum salicifolium – Smartweed [Damp ground] Polypogon monspeliensis - Annual beardgrass* [Damp ground, swamps] Potamogeton crispus - Curly leaf pondweed [Still-fast flowing waters] Potamogeton javanicus - Java pondweed [Still-fast flowing waters] Potamogeton ochreatus - Blunt pondweed [Still-moderately flowing waters] Potamogeton pectinatus - Sago pondweed Potamogeton perfoliatus - Clasped pondweed [Still-fast flowing waters] Potamogeton tricarinatus - Floating pondweed [Still-fast flowing waters] Pseudoraphis spinescens - Spiny mudgrass [Shallow water, mud] Ranunculus inundatus - River buttercup [Shallow water, stream margins] Ranunculus lappaceus - Common buttercup [Damp areas] Ranunculus muricatus - Sharp buttercup* [Damp areas] Ranunculus sessiliflorus - Annual buttercup [Damp areas, stream margins] Ranunculus undosus – Buttercup [Stream margins, damp areas] Rhynchospora brownii [Swampy areas] Rhynchospora corymbosa [Damp areas]

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Rhynchospora heterochaeta [Swamp areas] Rhynchospora rubra [Swampy areas] Ricinus communis - Castor oil plant* [Creek banks, shallow water] Rorippa nasturtium-aquaticum - Watercress* [Still-slow flowing waters] Rorippa palustris - Marsh cress* [Damp ground] Rumex crispus - Curled dock* [Damp ground] Rumex brownii - Swamp dock [Stream margins] Ruppia sp. - Sea tassel [Stationary fresh or saline waters] Sacciolepis indica - Indian cupscale grass [Margins of streams and swamps] Salvinia molesta - Salvinia* [Still-slow flowing waters] Schoenoplectus litoralis - Clubrush [Swamp areas] Schoenoplectus mucronatus – Three Cornered Rush [Creek banks] Schoenoplectus validus - River clubrush [Slow moving waters] Schoenus apogon var. apogon - Fluke bogrush [Damp soils] Schoenus brevifolius [Swampy areas] Schoenus calostachyus [Swamp areas] Setaria sphacelata var. sericea - South African pigeon grass* [Stream margins, damp ground] Sorghum halepense - Johnson grass* Sporobolus laxus [Damp ground] Triglochin dubium - Water ribbons [Deep-shallow waters] Triglochin procerum - Water ribbons Triglochin rheophilum [Still-fast flowing waters] Triglochin striata - Streaked arrowgrass [Shallow fresh/ brackish waters] Typha domingensis – Narrowleaf cumbungi [Stream margins, shallow waters] Typha orientalis – Broadleaf cumbungi [Stream margins, shallow waters] Utricularia aurea - Bladderwort [Swamps] Utricularia dichotoma – Purple bladderwort [Stream margins, damp ground] Vallisneria nana - Ribbonweed [Still-fast flowing waters]

Pennisetum alopecuroides - Swamp foxtail

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Freshwater Turtles Chelodina expansa - broad-shelled turtle Chelodina longicollis - snake-neck or longnecked turtle Elseya latisternum - saw-shelled turtle Elseya sp. aff. dentata - Mary River snapper Elusor macrurus - Mary River turtle Emydura macquarii krefftii - Krefft's river turtle Mary River Turtle The Mary River Turtle (Elusor macrurus) has been recorded in the main stem of the Mary River from Tiaro to Kenilworth and in Tinana and Yabba Creeks. Compared to fish species, the turtle has a reasonably small home range with the maximum upstream and downstream extent varying in the vicinity of 0.5 to 6 km. The species show a preference for free flowing water in and around riffle zones to a maximum depth of 5-6 metres. Their diet changes between life stages with juveniles feeding largely on riffle zone macroinvertebrates (74%) with macrophytes (81%) forming the dominant part of the adult diet. While terrestrial plant material comprises only 2% of the adult turtle’s diet, the fruit of the cluster fig (Ficus racemosa) is known to be sort after by the turtle. Many of the species consumed by the turtle are pollution sensitive species (eg. Ephemeroptera (mayflies), Trichoptera (caddis flies) and Vallisneria nana). The story of the Mary River Turtle is an unusual one. Even though it is one of the largest freshwater turtles in Australia, it wasn’t officially described until 1993. Thousands of baby turtles of this ‘new’ species were sold in pet shops throughout Australia during the 1960’s and 70’s, however their actual origin was a complete mystery. After a 30 year search, turtle expert, John Cann finally located the wild population unexpectedly in the Mary River. Because of the difficulties in locating this species, it was named Elusor macrurus (the elusive long-tailed escaper). Elseya sp. aff dentata Elseya sp. is a new species restricted to the Mary, Burnett and Fitzroy rivers. In addition to its limited geographic distribution, it is an uncommon turtle preferring stretches of river with intact riparian vegetation and pools with rocky outcrops. It is usually encountered near well-oxygenated

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reaches of calm water either upstream or downstream of riffle zones, but it is not found specifically in flowing water and probably cannot be considered a riffle specialist. This preference for well-oxygenated water appears related to its unique respiratory physiology, involving a cloacal gill system acting as a supplement to pulmonary respiration. As a member of the Elseya dentata group it is very large and can be expected to be slow to reach maturity and may lay only a single egg clutch per year. This animal is herbivorous, feeding largely on algae and the roots and shoots of submerged vegetation. It is most frequently caught in permanent pools fed by riffles or below weirs. Emydura macquarii krefftii Emydura macquarii krefftii is sometimes viewed as synonymous with the widely dispersed polytypic species Emydura macquarii. Morphology, coloration and geographic range has been used to separate the different sub-species: Populations of the Murray-Darling drainage and coastal rivers from the Brisbane River to the Hawkesbury-Nepean (Emydura macquarii macquarii), populations from coastal Queensland north from the Mary River to the vicinity of Princess Charlotte Bay (Emydura macquarii krefftii), from Fraser Island Emydura macquarii nigra, and from Cooper Creek in central Australia, Emydura macquarii emmotti. A number of other subspecies have been suggested for this widespread southern Emydura, and several others still prefer to regard Emydura krefftii as a distinct species. Emydura macquarii krefftii is widely distributed across eastern Australia and is common in a variety of aquatic habitats. It can be found in habitats with degraded water Elusor macrurus - Neil Armstrong quality but also lives in more pristine streams. It is a generalist in its requirements for habitat and food resources (omnivorous) and is particularly abundant in water storages where water level fluctuations prevent the development of a complex riparian zone and/or complex emergent and submerged littoral macrophytes. These conditions tend to exclude other species of turtles with more specialised needs. Two of the six species of turtles in the Mary System (Elseya sp. aff. dentata and Elusor macrurus) appear to have a declining population and a restricted distribution.

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Source Allen G. R., Midgley, S. H. and Allen M. (2002) Field Guide to the Freshwater Fishes of Australia Western Australian Museum. Burnett Mary Regional Group (2004) Country to Coast - A Healthy Sustainable Future Department of Natural Resources and Mines (2004) Mary Basin draft Water Resource Plan Environmental Conditions Report. Georges A. and Thomson, S. (in press). Evolution and Zoogeography of the Australian Freshwater Turtles. In Merrick, J. R., Archer, M., Hickey, G. and Lee, M. (eds). Evolution and Zoogeography of Australasian Vertebrates. AUSCIPUB (Australian Scientific Publishing) Pty Ltd, Sydney. Hydrobiology (2003) Aquatic ecosystem assessment for the proposed Cooloola Shire landfill, Toolara State Forest. Hydrobiology, Pty Ltd. 70 pp. Kennard, M.J. (2003) Appendix H. Freshwater Fish (Draft) In Brizga ed. Environmental Conditions Report Mary Basin Water Resource Plan. Natural Resources and Mines. Mary River Catchment Coordinating Committee (2001). Mary River and Tributaries Rehabilitation Plan. Department of Natural Resources, Brisbane. Mackay, S.J. (2003) Appendix F. Aquatic Macrophytes (Draft) In Brizga ed. Environmental Conditions Report Mary Basin Water Resource Plan. Natural Resources and Mines. McCord, William P., John Cann and Mehdi Joseph-Ouni (2003). A taxonomic assessment of Emydura (Testudines: Chelidae) with descriptions of new subspecies from Queensland, Australia. Reptilia (GB). 27:59-63. Emydura macquarii emmotti subsp. nov.; Emydura macquarii nigra subsp. nov. Pusey, B.J. (2001) Comparison of Fish Faunas of the Pioneer Valley Water. Resource Plan Study Area and Other Selected Queensland East Coast Catchments. Qld Department of Natural Resources. Pusey, B.J., Kennard, M.J. and Arthington, A.H. (2004). Freshwater Fishes of North-Eastern Australia. CSIRO Publishing, Victoria. Stockwell, B., Hutchison, M., Wedlock, B., Ford, E., Anderson, T., Thomson, C. and Stephens. K. (2004). Freshwater Aquatic Biodiversity in the Burnett Mary Region.

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Common Names of Australian Fishes The CSIRO Marine Research, Fisheries Research and Development Corporation, and Seafood Services Australia have joined forces with fish-book authors, fish taxonomists, recreational anglers, aquarists, and the fishing industry to produce a uniform list of common names for Australian fishes. These names will be published as "Standard Names of Australian Fishes" sometime this year. A draft list of names was constructed from options used in Australia for each species. While there will be regional preferences for some fish names over others, the use of one name per species across the country will have great benefits. The aim is to wind up with names that are unambiguous and manageable. The latest list (November 2004) of proposed common names can be viewed at http://www.marine.csiro.au/caab/namelist.htm Below are the proposed common names for some of the fish species of interest to our members! Ambassis agassizii - Agassiz's Glassfish Ambassis agrammus - Sailfin Glassfish Ambassis elongatus - Elongate Glassfish Ambassis gymnocephalus - Barehead Glassfish Ambassis interrupta - Longspine Glassfish Ambassis macleayi - Macleay's Glassfish Ambassis marianus - Estuary Glassfish Ambassis miops - Flagtail Glassfish Ambassis nalua - Scalloped Glassfish Ambassis vachellii - Vachell's Glassfish Bostrychus sinensis - Chinese Gudgeon Bostrychus zonatus - Sunset Gudgeon [Bostrichthys zonatus] Cairnsichthys rhombosomoides - Cairns Rainbowfish Chlamydogobius eremius - Desert Goby Chlamydogobius gloveri - Dalhousie Goby Chlamydogobius japalpa - Finke Goby Chlamydogobius micropterus - Elizabeth Springs Goby Chlamydogobius ranunculus - Tadpole Goby Chlamydogobius squamigenus - Edgbaston Goby Craterocephalus amniculus - Darling Hardyhead Craterocephalus capreoli - North-West Hardyhead Craterocephalus centralis - Finke Hardyhead Craterocephalus cuneiceps - Deep Hardyhead Craterocephalus dalhousiensis - Dalhousie Hardyhead Craterocephalus eyresii - Desert Hardyhead Craterocephalus fluviatilis - Murray Hardyhead Craterocephalus fulvus - Tawny Hardyhead Craterocephalus gloveri - Glover's Hardyhead Craterocephalus helenae - Drysdale Hardyhead Craterocephalus honoriae - Estuarine Hardyhead Craterocephalus lentigenosus - Freckled Hardyhead Craterocephalus marianae - Mariana's Hardyhead Craterocephalus marjoriae - Silverstreak Hardyhead Craterocephalus munroi - Munro's Hardyhead Craterocephalus pauciradiatus - Few-ray Hardyhead Craterocephalus stercusmuscarum - Flyspecked Hardyhead Craterocephalus stramineus – Blackmast Galaxias auratus - Golden Galaxias Galaxias brevipinnis - Climbing Galaxias Galaxias fontanus - Swan Galaxias Galaxias johnstoni - Clarence Galaxias Galaxias maculates - Common Galaxias Galaxias niger - Black Galaxias Galaxias occidentalis - Western Galaxias Galaxias olidus - Mountain Galaxias Galaxias parvus - Swamp Galaxias Galaxias pedderensis - Pedder Galaxias Galaxias rostratus - Flathead Galaxias Galaxias tanycephalus - Saddled Galaxias Galaxias truttaceus - Trout Galaxias Galaxiella munda - Western Dwarf Galaxias Galaxiella nigrostriata - Blackstriped Dwarf Galaxias Galaxiella pusilla - Eastern Dwarf Galaxias Glossogobius aureus - Golden Flathead Goby Glossogobius bicirrhosus - Bearded Flathead Goby Glossogobius celebius - Celebes Flathead Goby Glossogobius circumspectus - Mangrove Flathead Goby Glossogobius concavifrons - Concave Flathead Goby Glossogobius giuris - Tank Goby Gobiomorphus australis - Striped Gudgeon Gobiomorphus coxii - Cox Gudgeon Guyu wujalwujalensis - Tropical Nightfish Hypseleotris aurea - Golden Carp Gudgeon Hypseleotris compressa - Empire Gudgeon Hypseleotris ejuncida - Slender Carp Gudgeon

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Hypseleotris galii - Firetail Gudgeon Hypseleotris kimberleyensis - Barnett River Gudgeon Hypseleotris klunzingeri - Western Carp Gudgeon Hypseleotris regalis - Regent Carp Gudgeon Iriatherina werneri - Threadfin Rainbowfish Kimberleyeleotris hutchinsi - Mitchell Gudgeon Kimberleyeleotris notata - Drysdale Gudgeon Melanotaenia australis - Western Rainbowfish Melanotaenia duboulayi - Crimsonspotted Rainbowfish Melanotaenia eachamensis - Lake Eacham Rainbowfish Melanotaenia exquisita - Exquisite Rainbowfish Melanotaenia fluviatilis - Murray River Rainbowfish Melanotaenia gracilis - Slender Rainbowfish Melanotaenia maccullochi - McCulloch's Rainbowfish Melanotaenia nigrans - Blackbanded Rainbowfish Melanotaenia pygmaea - Pygmy Rainbowfish Melanotaenia solata - Northern Rainbowfish Melanotaenia splendida - Splendid Rainbowfish Melanotaenia trifasciata - Banded Rainbowfish Melanotaenia utcheensis - Utchee Rainbowfish Mogurnda adspersa - Southern Purplespotted Gudgeon Mogurnda clivicola - Flinders Ranges Mogurnda Mogurnda larapintae - Desert Mogurnda Mogurnda mogurnda - Northern Purplespotted Gudgeon Mogurnda oligolepis - Kimberley Mogurnda Mogurnda thermophila - Dalhousie Mogurnda Mugilogobius filifer - Threadfin Mangrove Goby Mugilogobius littoralis - Beachrock Mangrove Goby Mugilogobius mertoni - Chequered Mangrove Goby Mugilogobius notospilus - Freshwater Mangrove Goby Mugilogobius platynotus - Flatback Mangrove Goby Mugilogobius platystomus - Island Mangrove Goby Mugilogobius rivulus - Drain Mangrove Goby Mugilogobius stigmaticus - Blackspot Mangrove Goby Mugilogobius wilsoni - Wilson's Mangrove Goby Nannatherina balstoni - Balston's Pygmy Perch Nannoperca australis - Southern Pygmy Perch Nannoperca obscura - Yarra Pygmy Perch Nannoperca oxleyana - Oxleyan Pygmy Perch Nannoperca variegata - Variegated Pygmy Perch Pseudomugil cyanodorsalis - Blueback Blue Eye Pseudomugil gertrudae - Spotted Blue Eye Pseudomugil inconspicuus - Inconspicuous Blue Eye Pseudomugil mellis - Honey Blue Eye Pseudomugil signifer - Pacific Blue Eye Pseudomugil tenellus - Delicate Blue Eye Redigobius balteatus - Rhinohorn Goby Redigobius bikolanus - Speckled Goby Redigobius chrysosoma - Spotfin Goby Redigobius macrostoma - Largemouth Goby Retropinna semoni - Australian Smelt Retropinna tasmanica - Tasmanian Smelt Rhadinocentrus ornatus - Ornate Rainbowfish Toxotes chatareus - Sevenspot Archerfish Toxotes jaculatrix - Banded Archerfish Toxotes kimberleyensis - Kimberley Archerfish Toxotes lorentzi - Primitive Archerfish Yongeichthys nebulosus - Hairfin Goby

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Amphidromous Gobies

Lentipes multiradiatus - Gerald Allen

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he fish family, Gobiidae, is in one of the largest groups of teleost fishes, the suborder Gobioidei, or the fish commonly known as gobies. The group's size is best understood upon realizing that approximately ten percent of all fishes are gobies. In addition to being a large group, gobies live in a variety of different habitats. This variation in habitat, in addition to variation in external morphology, causes confusion about classification of these fishes. Amphidromous gobies belong mainly to the genus Lentipes, Sicyopterus, Sicyopus, Stiphodon, Awaous, Stenogobius, Schismatogobius and Rhinogobius for the Indo-Pacific area.

Few studies have investigated the reproductive biology of freshwater Gobiidae, particularly in their natural habitat. In general, the eggs are laid on the substratum, often on the underside of various supporting structures such as stones, rocks and crevices, but sometimes also on, or among, the vegetation. The females usually leave the nest unattended, or are driven away by the male fish, immediately after releasing the eggs. The male fish care for and guard the eggs as in many other species of goby. These species spawn in fresh waters, the free embryos drift downstream to the sea where they undergo a planktonic phase before returning to the rivers to grow and reproduce; hence they are termed amphidromous. Amphidromy necessitates special migratory abilities in larvae and juveniles. The post-hatch embryos appear in the

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marine environment when they have reached 1-4 mm in length where they spend only a few months before they must locate a source of fresh water when they have reached a length of 13-25 mm depending on the species and after their ‘metamorphosis’ into juveniles. The various measurements of larvae indicate that larvae occur at sea with a length that ranges from 13-16 mm for Lentipes, Stenogobius, Awaous and Eleotris and 23-25 mm for Sicyopterus. Soon after entering fresh waters, the juveniles undergo several changes in colour and fin shape. The body of these postlarvae is mostly translucent and light coloured when they enter the estuary, except for the eyes and internal organs. The tail is mainly forked but it gradually becomes truncated and the body acquires pigments as it metamorphoses and changes from a larval planktonic life to an adult benthic life. Pectoral and tail fins grow bigger, together with the pelvic disc needed for upstream movements. Theses gobies are able to use their fused pelvic fins (forming a suction disk) to make their way up tropical mountain streams of steep gradients including waterfalls. The mouth and the jaw structure are also modified, as well as the digestive system. The juveniles must switch from a planktonic feeding mode to a benthic feeding mode, when they ‘graze’ on the substratum. The rows of teeth will regularly be replaced so as to allow grazing. These gobies share a unique dentary modifications which, combined with a pelvic sucking disc, allow the fish to scrape algae from rocks in swift stream habitats. A fleshy

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sac is present above the upper jaw that contains replacement teeth in successive stages of development; as each tooth becomes worn, it is resorbed in the soft tissue of the premaxilla and replaced by another tooth from above. The crown of each tooth in different species is reported to be tricuspid, bicuspid or simple. The presence or absence of long papillae overlying the outer bases of the teeth is another important diagnostic character. Once in the river, the juveniles then migrate upstream, towards the adult habitat. The timing and direction mechanisms required for the success of this migration remain mostly unknown. The juveniles must migrate from the lower reaches of river habitats to the habitats they will occupy as adults. Out of the three genera living highest up river systems (Lentipes, Sicyopterus and Sicyopus), Lentipes is the only one to swim directly towards the upper reaches, while the other two take more time to complete their migration. In similar habitats in other geographic areas, amphidromous goby populations have evolved into landlocked forms (i.e., populations that spend their entire life cycle in freshwater). These gobies feed by scraping diatoms or algae from hard surfaces in the river. Many of these species have teeth adapted for scraping. The amount of plant cover on the banks of the river is another important factor where gobies’ habitat is concerned. Fish density is highest where plant cover is poorest. This is probably because primary productivity on rocks is higher in sunny locations, which provides more algae for the gobies to feed on. This might, however, not be the only reason: it is possible that light

plays a part in propagating the iridescent colours of displaying males. Whatever the cause, vegetation cover on river banks is a contributing factor in the distribution of gobies within streams. Gobies are a prominent part of riverine fish communities throughout the tropical Pacific, but information on the distribution, ecology, and taxonomy of many species is incomplete or lacking. The incomplete nature of this information can be directly attributed to the uncertain systematic and nomenclatural status of most genera, and the relatively few surveys of tropical streams.

Source Keith, P. (2003) Biology and ecology of amphidromous Gobiidae of the Indo-Pacific and the Caribbean regions. Journal of Fish Biology 63: 831-847 Watson, R.E. (1996). A review of Stiphodon from New Guinea and adjacent regions, with descriptions of five new species (Teleostei: Gobiidae: Sicydiinae). Revue Française d'Aquariologie 23(3-4):113-132. Donald W. Buden, D. Brian Lynch and Ronald E. Watson (2001). The Gobiid Fishes (Teleostei: Gobioidei: Sicydiinae) of the Headwater Streams of Pohnpei, Eastern Caroline Islands, Federated States of Micronesia. Micronesica 34(1): 1-10. Heiko L. Schoenfuss, Matthew L. Julius and Richard W. Blob (2004). Colonization of a recent, volcanically formed freshwater habitat: an example of primary succession. Ichthyological Exploration of Freshwaters 15 (1): 83-90

Stiphodon atratus - Gerald Allen

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A black bat on a black night consuming a Gambusia. Photo - Andrew and Simon Robson

Fish Ea t ing Ba t s - Pr eda t or s of Na t iv e a nd Exot ic species Geoff McPherson and Simon Robson

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n 1984 Australia’s big footed bat, Myotis macropus (from a recent DNA assessment for better or worse and variously known as Myotis adversus and Myotis mallacorum), previously thought to eat insects such as water boatmen and mayflies, was also thought to be a fish eater. The search was initiated after one of us (Simon) found fish scales in a greeting card left in his hand by a nervous bat. In 1970 Peter Dwyer (UQld) observed this species flying over water and dragging its long recurved toes through the water to collect fallen insects, and suggested that it might also catch the occasional fish. Sampling of dung piles beneath colonies in the vicinity of creeks in the north-west suburbs of Brisbane indicated that while faeces were dominated by insect remains, they also contained fish scales, namely ‘mosquito fish’ (84%), atherinids (6.8%), guppies (6.8%) and swordtails (2.3%). Full points should be awarded to the bats for reducing the exotic fish population, but it was a poor state of affairs for south-east Queensland creek systems if that was the species mix available to the bats.

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There have never been any reports of bats being stuck to surface logs by their claws, so it appeared that some degree of skill was involved in hunting over the water surface. Perhaps not surprisingly, fish eating bats are capable of taking flight from the surface of the water, an unusual characteristic for bats, but one that must be useful if striking a particularly large fish. More recent studies (Jones and Rayner 1991 for Myotis adversus) of fishing bat behaviour have clarified the hunting process. The species has a maximum wing span of about 27 cm and weighs only 9.5 grams. Fishing photos are not available for this species, it doesn’t win too many awards in the appearance stakes. The photo of a fish eating bat consuming what appears to be a Gambusia does bring out its more endearing qualities. In full hunting mode it would almost certainly look like a cross between a ‘dambuster’ Lancaster on a bombing run and a fire-fighting aircraft scooping water over a lake.

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The bats decelerate prior to dragging their claws for short periods