For the past 12 months AABio has been surveying the coastal creeks, streams and swamps of the Coffs Harbour City Council’s local government area. The surveys are now complete and the final report has been issued to Coffs Harbour City Council.
The focus of the survey is freshwater crayfish and crustaceans but all aquatic organisms are surveyed and recorded. We were specifically surveying for Tenuibranchiurus crayfish which are a rare and cryptic species in the area. Typically we would catch 150 C. cuspidatus for only one tenuie. We found abundant Cherax cuspidatus and Euastacus dangadi in the region plus numerous other crustaceans. So far we have found five different species of freshwater shrimp. Most species found are common and expected in the area, however we did make some startling discoveries.
We found some unusual species like limpets but of significance was the discovery of an extremely unusual freshwater crab. We were surveying a coastal creek flowing through a suburban Coffs Harbour area and finding long finned eels (Anguilla reinhardtii), intermediate spiny crayfish (Euastacus dangadi), plague minnows(Gambusia holbrooki), empire Gudgeons (Hypseleotris compressa), riffle shrimps (Australatya striolata), glass shrimp (Paratya australiensis), eastern river prawns, (Macrobrachium tolmerum), toebiters (Stenosialis australiensis), which were all common, abundant and expected. What was not expected was finding a freshwater crab! Not just any ordinary freshwater crab but something quite unusual. It’s a first for the ACP we hadn’t found these before. If in doubt I always contact the expert in that particular field. In this case its Peter Davie from the Queensland Museum, he’s the man for crabs and I asked him, “what this!” He advised it’s a River Swimming Crab, Varuna litterata. A marine crab known to occur in freshwater, being excellent swimmers and able to move with the currents along the coast. In Australia they have only been recorded from south east Queensland and north into Northern Australia (Qld Museum). They are also known to occur in India, East Africa and Japan. The discovery of this species this far south greatly increases the known distribution of the species. A specific research projects to acquire new knowledge on this species has been started with The Australian Crayfish Project www.austcray.com Eventually we will submit a scientific paper on the range extension. For an article with more photos, site locations, water quality data, etc. Go to: River Swimming Crab Article. http://www.austcray.com/2014/08/river-swimming-crab-herring-bow-crab-varuna-litterata-2/
Our thanks to Coffs Harbour City Council and specifically to Rachel Binskin, their Biodiversity Officer for their support of the research project and patience awaiting its completion. The project dragged on longer than expected.
Aquatic Biodiversity Survey and Baseline Mapping of Freshwater Crayfish and Aquatic Species of the Gosford Local Government Area
As Part of the Australian Crayfish Project and a sub project 100056 we have been conducting aquatic biological surveys the whole of the Gosford LGA. This project is major sponsored by Australian Aquatic Biological and receives sponsorship from Gosford City Council under their Ecological Research Grants scheme 2010. The project reached fruition in May 2012 with a total of ten aquatic biological catchments reports being issued to Gosford City Council.
The biological surveys were undertaken as part of both the broad Australian Crayfish Project (ACP) and Australian Aquatic Biological Survey (AABS) and a targeted sub-project on the Gosford LGA, Project 100056, Australian Aquatic Biological 2010.
Surveys of the Gosford LGA are completed on a catchment/drainage basis and a total of ten catchment areas were independently surveyed.
1 Wamberal Lagoon
2 Terrigal Lagoon
3 Avoca Lagoon
4 Cockrone Lagoon and Surrounds
5 Green Point to Kilcare & Bouddi NP – Coastal Streams
6 Erina Creek
7 Narara Creek 100056-7 Completed 67, 77, 78, 86, 87.
8 Point Clare to Mullet Creek
9 Mooney Mooney Creek
10 Mangrove Creek to Wisemans Ferry
This was a two year project that discovered much new information The primary aim of Project No. 100056 is to determine what freshwater crayfish occur where in the Gosford LGA. Primarily freshwater crayfish are the priority and the Gosford LGA represents a significant area for crayfish distributions, yet little is known on the distributions of crayfish in this area. Prior to the start of this research project only two species have recorded distributions within the LGA (Euastacus australasiensis and Euastacus spinifer) yet the extent of their distribution are unknown. Additionally, the area includes a number of coastal lagoons, lakes and streams all with independent catchments draining directly to the Tasman Sea that have been isolated from each other for millions of years and many containing unrecorded crayfish species.
The project also records information on all the other aquatic fauna found in the LGA as well as information on landforms and vegetation. All this is in order to facilitate the better conservation and management of the aquatic ecosystems of the Gosford LGA.
Note: For environmental and hygiene reasons (transfer of pests, diseases and weeds, etc.) each of the catchments are treated as individual systems and are surveyed separately with equipment and personnel being sterilized between catchments. A copy of our Hygiene Protocol and Code of Practice is available online at www.aabio.com.au
We managed to map the distributions of four freshwater crayfish species that occur in the Gosford LGA. Euastacus australasiensis, Euastacus spinifer, Cherax destructor and Gramastacus sp.