At the start of the dry this year, Cape York NRM and Rodney and Anne Raymond, the property owners of Kimba Station, arranged for James Cook University fish ecologist Ebb, to survey fish and crabs in the local waterways.
The purpose of this first field trip was getting baseline estimates of the aquatic fauna prior to fencing off a reach of the Alice River from being accessible to cattle. A primary focus was on the Tiger crab (Austrothelphusa tigrina), which is an endemic species that is currently only known from the western slopes of the Kimba Plateau.
Ann Raymond from Kimba Station said her family had known that Tiger crabs were special, and unique to the region, since her son Shane did some research for a school project.
Ebb is hoping that more properties owners on the Cape and recreational anglers that come across this stunning type of crab, might contact him to help map out the wider distribution of the critter. A photo and a GPS point or a rough location would be a handy start.
Vicki Wundersitz assisted with the surveys and was responsible for counting the number of crab holes in the banks. Vicki and Ebb nick-named these facilities ‘hotels’, but essentially they resemble a mud- coloured, Swiss-cheese river bank. Of the 15 hotels that were fully inspected, the least holes were 24 and the most was 276, with an average of 121 holes. Six of these motels showed signs of pig damage.
Apparently crab truffles are in demand.
The Tiger crab spends about half of its year underground and cuts loose during the wet. The study turned up two types of crab, the common freshwater crab which is typically a plain washed out grey or brown colour, and the unmistakable tiger crab. The Tiger crabs were generally larger than the common freshwater crab, but the latter species was found at a number of small creeks where the Tiger crabs and their hotels were absent.
Small fish were about but not in great numbers at most sites that were surveyed. In some places the rapid drying of the river was leaving small rainbowfish flapping about and short of a future. Presumably the 4WD capability of the crabs ensures a final banquet of stranded fish before the crabs go into hibernation for the dry. A second trip is planned for the end of this upcoming wet season.
For further information or to report a sighting contact: Vicki Wundersitz P: 07 4095 7132
E: vwundersitz@capeyorknrm.com.au
Ebb P: 07 40918805 E: brendan.ebner@csiro
This project is supported by Cape York NRM through funding through Australian Government’s National Landcare Programme.
