Australian Aquatic Biological

Australian aquatic biodiversity research and consultancy

Central Highlands Burrowing Cray Engaeus affinis (Smith & Schuster 1913)

Engaeus affinis from a communal burrow, Healesville, Vic

Engaeus affinis from a communal burrow, Healesville, Vic

This species is endemic to Victoria with a relatively small distribution known at this time (estimated extent of occurrence of approximately 200 km2). Found in the upper Yarra, Acheron, Yea and Big Rivers. An area roughly from Kinglake to Eildon to Jamieson to Noojee to Hoddles Creek. Central Highlands Burrowing Cray Engaeus affinis has been assessed on the IUCN Red List as Data Deficient. 

Engaeus affinis, Healesville, Vic

Engaeus affinis, Healesville, Vic

It’s a robust species and at many sites relatively abundant. Typically, it’s a communal burrower, both type 2 & 3 burrows with multiple surface entrances (20 or so) over a square metre. Both fans shaped entrances and chimneys. Surface openings descend into large central burrows. Central burrows are relatively large in diameter (150 to 200 mm), typically water filled and tending horizontal and descending and converging into a larger chamber.

Engaeus affinis, Badger Creek, Vic

Engaeus affinis, Badger Creek, Vic

Typically, the easiest way to capture is to excavate down to the water level, usually from 200 to 600 mm deep. Once water is found, wait, (patience required), larger males will come to investigate the disturbance and you can grab them, otherwise, every 5 minutes or so, shove your hand down the burrow and feel around in the water. If you are lucky and have good feeling in your fingers you should be able to grab one every 5-10 minutes. That’s the way we collected the specimens for this article.

Burrow entrance, Badger Creek, Vic

Burrow entrance, Badger Creek, Vic

Those from Healesville were in a yellow clay on the slope beside a creek approximately 1.2 metres above the creek water height (7 metres from creek bank) but had water at 650 mm in the burrow system. Those from Badger Creek were in a fine silty material in a seepage area in the tree fern forest with water only 100 mm below ground level and over 100 m from Badger Creek.

Engaeus affinis, Badger Creek, Vic

Engaeus affinis, Badger Creek, Vic

Happy Yabbying

Cheers

Rob

Lowland Burrowing Crayfish Engaeus quadrimanus

Also known as “The Mernda Land Yabby” Engaeus quadrimanus (Clark 1936) is a relatively widespread and locally abundant species. It’s a lowland species generally found under 250 m a.s.l. from just north of Melbourne, east along the Victorian coast to just before the NSW border. Engaeus quadrimanus has been assessed as Least Concern on the IUCN Red List.

Engaeus quadrimanus - note the burrow entrance behind

Engaeus quadrimanus – note the burrow entrance behind

This specimen is from the west of the range. Collected from the bank of Fish Creek a tributary of the Tarwin River crossing Meeniyan-Promontory Rd, Fish Creek, Victoria.

A very robust and adaptable species that usually has large colonies with the area being riddled with burrows. Typically, burrows are round to oval in shape and open with excavated material at the entrance (see photo). In some areas they can create a pelleted chimney but for many areas it’s just an open hole in the ground as the excavated material has been washed away with flood waters. Burrows are type 2 and relatively basic with only 2-3 surface entrances descending to a horizontal corridor then a deeper burrow to water table. Typically most of the burrow system is flooded and typically they are individual burrows with both males and females having their own burrows. One of the keys to the species is that they are intersexed so hard to determine which are males and which females. Breeding season is autumn and they can be found sharing burrows together then. The species is extremely active during flood events and uses the creeks to migrate and find mates, etc.

Fish Creek

Fish Creek

For a similar article on this species and images from populations further east, go to: http://www.austcray.com/2015/09/engaeus-quadrimanus-from-cann-river-victoria/

Cheers
Rob

 

A New Spiny Crayfish in Western Drainage, NSW.

Project: 100007 started back in 2008 final draws to a closure. The project that started out as an unidentified Euastacus crayfish species has been found in western drainage of NSW has been finalized with the completion of the project going to press.

The New Euastacus species for NSW showing an unusual colour variation

The New Euastacus species for NSW showing an unusual colour variation

A scientific manuscript title; Euastacus sp. nov., a new giant spiny crayfish (Crustacea, Decapoda, Parastacidae) from the Great Dividing Range, New South Wales, Australia, by Robert B. McCormack & Shane T. Ahyong has been completed and submitted to the journal Zootaxa.

The New Euastacus is a true spiny crayfish with numerous large sharp spines

The New Euastacus is a true spiny crayfish with numerous large sharp spines

The new species is described from the upper Cudgegong River, New South Wales, Australia This new species occurs in the western drainage of the Great Dividing Range, and is most closely related to E. spinifer (Heller, 1865), which occurs on the eastern side of the range. The new species differs from E. spinifer by its considerably smaller maximum size, greater degree of thoracic spination loosely arrayed in three instead of two rows, genetic sequence divergence in COI and unusual colour variations.

The new species is small in size with the majority of the female population breeding each year

The new species is small in size with the majority of the female population breeding each year

Both Euastacus armatus and the new Euastacus species occur in the upper Cudgegong River and this has led to much confusion in the past. Recent research by Whiterod et al., 2016 indicates that the E. armatus population in the upper Cudgegong is a translocated population.

In our present study, we formally describe this new Euastacus species, increasing the number of species of Euastacus to 53.

Cheers
Rob McCormack

Disused Aquaculture Ponds Wanted to Lease

Got an aquaculture facility that’s not operational or not making the amount of money you desire. Why not lease your farm or your ponds? We have clients in desperate need of ponds now.

Aquaculture is the fastest growing primary industry in Australia. Demand for aquacultured produce is skyrocketing and new production methods are increasingly improving profit margins making modern land based aquaculture an increasingly lucrative enterprise.

Unfortunately, difficulties in obtaining approvals for new ponds and the ensuing time delays in receiving approvals and then building ponds makes the interest level in existing ponds extremely high.

Existing yabby and fish ponds are wanted now so that large scale commercial farmers can expand their production by using your ponds. They come to you, use their staff, their equipment and technology, to get your ponds into commercial production. They don’t need you to do anything at all, you do not need to expend one cent towards the enterprise. They just rent your ponds or property nothing more.

If you have ponds not producing much or haven’t been in production for years then contact us for further details. Perhaps we have a lucrative solution to create a substantial, reliable income without any effort or expense from your end.

Contact

Rob McCormack

RBM Aquaculture

rob@rbmaqua.com.au

The Australian Crayfish Project Team Visits Tasmania

In early May four members of the ACP visited Tasmania.  We are also members of the NSW Aquaculture Association and one of the reasons for visiting Tassie was to visit Huon Aquaculture. For an article of Huon see: http://nswaqua.com.au/huon-aquaculture-sea-cages/  Whilst in Tassie we took full advantage of the opportunity and travelled the country from one end to the other. We flew into Launceston and hired 3 campervans, Paul and I had one each and the Burnes brothers shared a van. Despite the constant rain, snow and wind we had a great time in Tasraina.

Our first camp site

Our first camp site

The first night saw us camped at the end of a small track on the Great Forester River. We didn’t have any bait so dragged a bit of road kill (dead wallaby) and tied that up on the edge of the river to see if it attracted anything.

The bait-a dead wallaby

The bait-a dead wallaby

Paul Burnes with a 1.5kg Astacopsis gouldi

Paul Burnes with a 1.5kg Astacopsis gouldi (eastern Tasmania)

Surprisingly we managed to attract a 1.5 kg giant Tasmanian lobster. It was a bit of a surprise and only quick action by Craig saw it captured by hand. It was a female but not berried even though I would have expected it to be breeding season. After a photo shoot we release here back into the river, but a great start for us.

Galaxias were common and abundant

Galaxias were common and abundant

We observed large numbers of eels in the creeks and lots of Galaxias as we spotlighted the creeks and rivers at night.

Opportunistic surveying

Opportunistic surveying

We didn’t have a plan as such we were just driving around checking out the country side and stopping at likely spots to see if we could find a crayfish and have a photo shoot of the catch of the day.

Tasmanian Engaeus laevis

Tasmanian Engaeus laevis

Engaeus crayfish were quite common and the first specimens we found were Engaeus laevis.

Engaeus fossor

Engaeus fossor (green tint)

We also found a number of Engaeus fossor. Interestingly we found quite a large colour variation in the species.

Engaeus fossor

Engaeus fossor (Tan tint)

Engaeus crayfish are relatively easy to find, their presence is given away by their chimney shaped burrows. They are a deep burrowing crayfish so knowing where they live and then actually getting a specimen out of the burrow is a very different matter.

Looking for Engaeus crayfish

Looking for Engaeus crayfish

Large parts of Tasmania suffered from bush fires over summer. This however made it easier for us to find the burrows.

Engaeus burrows

Engaeus burrows

Its always good to find something new. Paul V managed to catch an Engaeus lengana. Thats the first time I’ve ever seen one so very happy with that catch.

Engaeus lengana

Engaeus lengana

Just being tourists an traveling around the whole state we didnt have much in the way of survey equipment, basically it was all capture of crayfish by hand.

Looking through a creek

Craig looking through a creek

Small creeks in remote areas produced a surprising number of crayfish species. This creek was full for Astacopsis tricornis.

Astacopsis tricornis

Astacopsis tricornis

Unfortunately, the weather was less than cooperative with high winds and rain. The state was in drought till we got there. Once we arrived the heavens opened.

Blocked roads were a repetitive theme

Blocked roads were a repetitive theme

Nearly all our travels through Tassie were on the back roads. Unfortunately, with the high winds and rain, trees down were a huge problem for us. The boys managed to clear this fallen tree with the saw on a pen knife. We managed to get another 2 km up the road before we were stopped by huge fallen trees that completely blocked the road.

Another roadside campsit

Paul V (left) and Paul B (right) at another roadside campsite

We were fully self sufficient so we would make camp, survey the area around the camp and await rescue by someone with a big chainsaw.

Rob McCormack with a Giant Tasmanian Lobster Astacopsis gouldi

Rob McCormack with a Giant Tasmanian Lobster Astacopsis gouldi

One of the highlights of the trip was spending some time with Todd Walsh and researching the Giant Tasmania Lobster Astacopsis gouldi. We all had a great time with Todd who was a wealth of information on this iconic species. If you would like to read more about our time with Todd see: http://www.austcray.com/2016/06/tasmanian-giant-freshwater-lobster-astacopsis-gouldi/

Paul Van der Werf with a 2.5 kg Astacopsis gouldi

Paul Van der Werf with a 2.5 kg Astacopsis gouldi

Despite the rain Craig Burnes is happy with this Astacopsis gouldi he caught

Despite the rain Craig Burnes is happy with this Astacopsis gouldi he caught

I had a fantastic time in Tassie with a great bunch of mates. We were cold an wet most of the time, spent long hours going short distances, spent hours digging holes, trudged up and down mountains, had to abandon camp in the middle of the night just before the floodwaters washed us away, cleared fallen trees off the road with a penknife, and spent endless hours at the end of the trip cleaning the mud out of our campervans, but despite all that- I wouldn’t have missed for the world.

Cheers

Rob

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