Freshwater sponges are very primitive organisms, members of the phylum Porifera (which means “pore bearer”). They have relatively soft bodies full of channels and pores allowing water to circulate through them. Their bodies are a network of fibres and branches with needle type projections – quite weird under the microscope.
I’m not a spongiologist and typically just look and don’t touch, however, recently with the increasing drought, dams, lakes and rivers are drying up and the sponges which would normally be in deep water are becoming exposed and this has attracted my interest.
There are over 20 species of freshwater sponges in Australia, this one is from central west NSW. I’ve no idea of the species, if anyone knows I’d be interested in your knowledge. Typically, the sponges I see are on rocks and logs and usually a thin mat of sponge (<1cm thick) covering a broad area. These sponges are closer to the saltwater sponges I’m used to.
These sponges only seem to grow on submerged sticks and logs at depth. They seem to like the cooler deep water and shallow hot water seems fatal to them. If we move these sponges into warm water they “dissolve” and form gemmules.
Formation of gemmules is asexual reproduction. Gemmules are small round tough-coated dormant cluster of embryonic cells that can survive harsh conditions and await the return of favourable conditions when they will “hatch” and grow into a genetically identical copy of the original “parent” sponge.
Sponges seem slow growing, don’t know how long these ones live for, but they must by many, many years old. They are filter feeders so help clean the water and their loss on mass across the dams, lakes and rivers of eastern Australia due to the unprecedented drought will take many years to recover and be a loss to water quality when the water returns for many years. Another long term negative consequence for our freshwater ecosystems from the drought.
Australian aquatic Biological and its subsidiary RBM Aquaculture has had another extremely busy year with numerous consultations.
We designed and assisted with approval for a new Redclaw crayfish (Cherax quadricarinatus) Farm in Queensland this year. Interest in Redclaw aquaculture continues to grow in Queensland with continued investment. We designed a new aquaculture facility with 12 nursery ponds (25 x 10 m), 35 growout ponds (50 x 20 m), 4 sediment ponds (75 x 20 m), plus a water storage dam and purging facilities, etc. This consult was successfully completed this year with approvals from DAF, DSDMIP and Council being granted.
Consultation with a new Murray Cod farm just over the border of NSW in Victoria was completed this year. This consult also provided the opportunity for a holiday in Victoria for the wife (Cheryl), the family dog (Binx) and myself.
We designed and assisted with the licencing of a new Yabby (Cherax destructor) Farm in NSW. NSW DPI instigated a new regulation this year requiring a Farm Biosecurity Risk Management Plan to be created, submitted and approved prior to aquaculture permits being granted. This was something new from NSWDPI and over the year we generated a number of plans but each time they were rejected and the department required greater information. The problem was that DPI didn’t have a template or much direction and being the first to submit a plan we became the test case. We worked with DPI on not just this biosecurity plan but others as well for our other clients and finally this project was completed with approval granted and aquaculture permit issued.
This facility has 19 growout ponds (50 x 20 m), 2 sediment ponds (75 x 20 m), water storages, irrigation areas and purging facilities etc.
Pre approval from NSW DPI Fisheries has been granted but this consult is ongoing into 2019 as it was submitted to council in December 2018.
We have designed a new Murray Cod, Silver Perch, and Yabby Farm for NSW this year.
It’s in the developmental stage at the moment with designs, applications, SOMP and Biosecurity Plan created but this project will be ongoing into 2019.
Long term consultancy with the Queensland Government has continued throughout the year. AABio has been engaged to supply expert opinion on freshwater crayfish and land based aquaculture to the Qld DSDMIP and DAF. This consultancy is ongoing and will continue in 2019.
Long term consultancy with Jamie Williams of Yabbydabbadoo Yabby Farm was terminated in early November 2018.
Basin View Gardens. Regular services and support for the Royal Freemasons’ Benevolent Institution’s award winning aquaponic garden at Basin View, NSW has continued this year. Paul Van der Werf designed the integrated garden and then Paul and I built the Garden at RFBI Basin View Masonic Village back in December 2011. Since completion the aquaponic gardens have flourished being the subject of praise from all quarters, and a number of scientific studies commissioned on the health benefits of the gardens for the Retirement Village Residents. At the time this was the largest aquaponic garden in the southern hemisphere and won an International Academy of Design and Health Award. The International Academy for Design & Health is a global, interdisciplinary knowledge community dedicated to the stimulation and application of research concerning the interaction between design, health, science & culture.
Since construction AABio has conducted regular service and maintenance of the garden. Significantly this year, the last of the Silver Perch were removed from tank 3 and replaced with ornamental fish (Koi & Goldfish). The ornamental fish supply a better visual stimulation for the village residents compared to the silver perch that only became clearly visible at feeding time. Our thanks to my mate Craig at Albatross Aquaculture for the supply of all our ornamental fish. The garden continues to supply high quality organically grown leafy greens and vegetables for the residents, the hostel kitchen and excess for fetes, etc.
Numerous other smaller consultations have also been completed. Plus long term consultancy with a number of our previous major clients continued throughout the year.
Ecological Consultancy (major projects)
Another year of monitoring streams and crayfish populations for BMCC has been completed. Our long term ecological monitoring program is collecting valuable data and assisting with long term management actions to improve aquatic and riparian environments.
This year our aquatic surveys were expanded to include the Springwood Creek catchment. Data collected over the last 4 years is being included in a scientific manuscript currently in preparation.
Additionally, this year we attended the Leura Swamp Fest, held at Peter Carroll Oval in September 2018. We did a number of presentations “Up Close with Freshwater Crayfish” presenting information on the crayfish species present in the streams of the Blue Mountains and their importance as keystone species.
Euastacus gamilaroi. The imperiled Gamilaroi crayfish, Euastacus gamilaroi Morgan (1997), was described from a single specimen collected in 1954 from the vague location of Hanging Rock near Nundle, New South Wales (NSW). Since 1954 no further specimens have been lodged in museum collections or any detailed account of any aspect of the biology and ecology of this critically endangered species. Our current project aims to fill this knowledge gap. Over the year we had 6 expeditions gathering information and we intend to finalize and publish our findings in 2019.
Cape York expedition 2018.
As part of the Australian Crayfish Project, AABio sponsored an expedition to Cape York in July and August. This was an extremely productive expedition with a vast amount of knowledge gained that will take several years to be fully utilized.
Two new Cherax species and a number of papers on known species are currently in preparation.
No scientific papers were published this year but several are nearing completion.
No new books published this year, however, Keeping Pet Yabbies has been updated with a new edition.
The 3rd Edition 2019 is currently at the printers and will be available in all good book stores by the 1st week of January 2019. (BUY PET BOOK)
A guide to Australia’s Spiny Freshwater crayfish continues as a best seller this year.
RBM Aquaculture (Nets and Traps)
Net and traps sales continued this year with strong demand for commercial nets. The 14m super yabby trap continues with strong demand. We import these traps directly from the manufacturer in China and we only sell the heavy duty trap with the extra heavy duty cod end. This makes the traps expensive to purchase but if you want a trap you can use commercially every day year after year then these are the traps for you. Unfortunately, there are some very cheap, light weight 3.2 metre similar traps on the market that don’t catch much or last any time at all, “Buyer beware” “You only get what you pay for”.
Opera House trap sales have also gone through the roof this year. Commercial traps with no rings are the big seller. These type traps catch and retain far more yabbies than normal traps with a ring. We sell both a light duty and an extra heavy duty style trap. The extra heavy duty are the ones in huge demand by both commercial crayfish farmers and commercial fishers. Commercial fishers fit their own rings to these traps. (BUY TRAPS)We have had a great deal of difficulty securing supply of these traps in any quantity from our traditional manufacturer that charges an arm and a leg for them. The two attempts with alternate Chinese manufacturers were both a failure as the sample trap they manufactured and sent to us were not to our specifications or an acceptable standard.
A warning for all you commercial crayfish farmers that like using opera house traps. All opera house traps are made overseas, we have had great difficulty dealing with manufacturers as opera house traps without rings are banned in Australia for recreational fishing and even ones with rings are banned in States like Victoria. If the anti opera house trap lobby has their way they will be completely banned from import into Australia. I expect it is only a matter of time before opera house traps will no longer be available, you should stock up now whilst you still can.
The large opera house traps NO RING have also seen a huge surge in sales. Traditionally used to catch eels from farm dams, more and more commercial fish farmers are using them to catch fish from farm dams. Murray Cod, Carp and Silver Perch farmers are snapping them up. Again, these are traps that may not be available in the near future.
Mid West Yabby & Fish Traders
A quiet year for Mid West with only small amounts, less than 250kgs of yabbies being traded.
This will increase in future years, a new holding and purging facility is currently under construction as part of the AustSilvers development.
Stainless steel holding/purging tanks are being utilised, these tanks are available as a speciality item through the RBM Aquaculture website.
Stainless steel tanks are 2000mm x 800mm floor with a 200 mm wall x 1.5mm 304 Stainless Steel with a 25 mm BSP drain.These are purging/holding tanks are $385 each plus GST ex Sydney or Swan Bay (2424) NSW. Just send me an email if you want any, typically, they are supplied to our consult customers but happy to sell to anyone.
Construction of AustSilvers aquaculture facility began in late 2017. We have had a full year of development and construction occurring but we are still a long way from completing. This is a full aquaculture development being constructed from scratch.
Stage 1 ponds have been constructed. Each pond is gravity drainable, with its own independent water and air supply.
Bird netting frame work is under construction for all ponds and the first pond has been netted
The fish hatchery has been constructed and is in production with breeding of Silver Perch Bidyanus bidyanus being successfully achieved in the new hatchery.
The first silver perch fingerlings were harvested in late December 2018 The first harvest was of larger advanced fingerlings that were the offspring of our best genetic lines. These fish will mostly be used as future broodstock and were restocked into our own dams and ponds. We have another 200,000 fish in the ponds ready for harvest in the new year. (BUY SILVER PERCH FINGERLINGS)
Freshwater mussel culture is well underway, both bottom holding trays and floating cages have been constructed and installed in the Silver Perch broodstock ponds. Each of the 2 current broodstock ponds holds 10,000 mussels.
The Silver Perch broodstock act as the host for larval mussels and some mussel breeding has occurred in 2018.
Mussels sales for private farm dams and koi ponds has been strong with over 12,000 sold this year.
The mussels are also part of a freshwater pearl project, however, the construction of new facilities has consumed all our efforts and no further progress was made this year on pearl culture, however, the infrastructure is being developed ready for the future.
In 2017 the Hunter Region of NSW was suffering from the worst drought in 50 years. In late 2017 my local creek at Port Stephens dried up for the first time in the last 18 years since I’ve been here.
As the water dried out, I took the opportunity to investigate all the species that occur in my creek. The shallows of the creek dried rapidly but the deeper pools retained water through most of the 2017 period.
Interestingly, I observed freshwater mussels moving from the shallows into the deeper water. They use their foot which is tongue like to push themselves along. This leaves a trail in the sediments which you can easily follow to the mussel.
I was quite surprised by the sheer number of them that were in my deeper pool that I would normally use as a fishing and swimming hole. Typically its over 3 metres deep but the drought saw it shallowing to less that 300mm. Freshwater mussels are great indicators of your streams health. They are sensitive to pollution and sedimentation so if you have healthy populations, your stream is more than likely healthy.
The water in the bottom of my pool was clear, warm and shallow so I decided to survey the freshwater mussels in it. I systematically, worked my way by hand through the bottom sediments, feeling for mussels and counting them.
Interestingly, I found around 2600 mussels in the pool. That’s great news and indicates my creek is generally health and has been so for quite some time. Mussels are very long lived 20-40 years and these were a good mix of small to large old mussels that I was finding, indicating healthy conditions for many years.
Unfortunately, I’m not a freshwater mussel expert but I have spent some time over the years with experts helping them collect mussels for identification. The mussels I found were all very similar in size, colour and shape. However, if you looked closely, occasionally, I would find something different.
The most common and abundant freshwater mussel was Hyridella drapeta.
Interestingly, in amongst the 2600 mussels were around 160 different ones, these were Hyridella australis.
They look very similar but if you look closely they have v-shaped sculpturing on the beaks of the shells.
Freshwater mussels are natural biofilters processing large volumes of water. They remove large quantities of nutrients, algae, bacteria and organic matter which helps to clean water bodies. Both H. australis and H. drapeta are classed as river mussels. They need permanent and flowing water to breed and survive so generally found in permanent flowing streams.
Many people want freshwater mussels for their fish ponds or farm dams to help keep them clean. River mussels are not suitable and will eventually die in a static water dam or pond. However, there is one species that thrives in static water dams and ponds. That’s the flood plain mussel Velesunio ambiguus. This mussel will live and breed up to huge numbers in your ponds and helps to keep your water clean. This is a commercially, cultured species so available for purchase from aquaculture farms like AustSilvers or if you just want one or two for a fish tank then check with your local aquarium shop.
BTW, If you want to start a sustainable population going in a farm dam you will need several hundred as initial stock.
Freshwater blood and fluid sucking leeches can pose a serious problem for freshwater crayfish. Typically it’s the common yabby (Cherax destructor) that you find leeches attached to or they have a nasty round scar indicating a leech has had a feed. The scar remains until the crayfish moults but the scar itself can create difficulty in moulting and can lead to the death of the crayfish. From an aquaculture perspective, leeches in your ponds are a big NO-NO and every effort should be made to catch and remove them as the unsightly scars on crayfish make them unsellable.
Most leeches can ingest several times their own weight in blood at one feeding and swell to a large fat size. Leeches attach to their hosts and remain there until they become full, at which point they disengage and fall off to digest their huge feed. Crayfish are most vulnerable when they are freshly moulted. Freshly moulted crayfish are already stressed out and weakened by the moult process, the additional blood loss from a leech feeding could be fatal. This risk of mortality is greatly increased if the crayfish is small and the leach large.
The example Marron with a leech attached was found in the swimming hole below North Dandalup Dam, WA.
Images compliments of Tegan & Josh Moylan
SORRY – THIS SYSTEM HAS BEEN SOLD
A complete fish hatchery and grow out recirculating aquaculture system is currently for sale. If you are thinking of entering the Recirculating Aquaculture Industry and can’t afford the $500K price tag for a brand new system, then purchasing a second hand system at 30% of the new price may be the perfect option for you.
Second hand systems coming on the market are rare so you need to act quickly when they do come up. Now due to retirement of the owners a complete RAS system is currently offered for sale.
The system belongs to Glencoe Fish Hatchery (GFH) which supplied weaned pellet feeding Murray Cod fingerlings to other RAS grow-out systems of the commercial aquaculture industry, plus grown out Barramundi for the restaurant and market trade in Melbourne. All fingerlings produced in the RAS by GFH came with a veterinary certificate to guarantee their health. Glencoe Fish Hatchery are proud to be one of the first hatcheries to have inside brood stock of Murray Cod which guarantees when they breed, their offspring will be of a high quality and health standard as the internal brood stock are not live caught but born and bred in tanks which means their natural instincts have changed and they live wholly on a pellet feed diet.
Glencoe Fish Hatchery was aimed at the commercial market with the system’s capacity around 100,000 fish per batch and several batches per year. Glencoe Fish Hatchery strived to have the best fish on the market in both health and appearance.
The complete system as a single unit is for sale.
The system is currently intact and complete available for viewing. The owners will dismantle and make it ready for transport by the purchaser. Each section would be labelled ready for reassembly by the purchaser.
For Further Information Contact: Andre Henry Phone: 0427 640 844 Email: email@example.com All equipment is viewable by appointment only, at: Glencoe Fish Hatchery 2333 Loddon River Road, Appin South Victoria 3579