Summary

Aquabait is an aquaculture facility that propagates marine worms. These marine worms are highly sought after on the recreational fishing bait market. Currently the only other method of obtaining these marine worms for bait are through licensed diggers. Aquabait Marine Worm Farm is a facility that can provide an alternative bait and aquaculture feed onto the market that is not obtained through exploiting the natural stocks and therefore no damage is caused to the fragile intertidal zone. Aquabait has taken sustainable aquaculture further by the farm set-up itself. Aquabait is positioned adjacent to Eraring Power Station, on Lake Macquarie catchment, New South Wales. This position will enable Aquabait to utilise the cooling water from the power station outlet channel to create increased growth rates all year round, in turn increasing yield. Aquabait has also structured its ponds to create a clean outflow of water from the farm by the addition of Settlement Ponds, and by the filtering system of the ponds themselves. This paper discusses the methods that Aquabait Marine Worm Farm has implemented in order to become a sustainable facility, and how Aquabait is positively contributing to reducing environmental damage within the intertidal zone on Australia’s coastline.

Aquabait Marine worm farm is located on Lake Macquarie catchment on the New South Wales Central Coast. The farm itself is positioned close by to one of the most productive coal fired power stations in New South Wales, Eraring Power Station.
Aquabait Pty Ltd was established in 1996 and until today has been developing its own technology within a controlled laboratory environment in conjunction with the best marine polychaete (segmented marine worms) scientists in Australia to provide a sustainable product.
Aquabait provides live and preserved marine “tube-worms” onto the recreational fishing bait market currently. Future markets will include the marine worms being used in the diet of other aquaculture species, from various finfish to crustaceans. The “Tube-worm” is a relative to the beachworm by sharing the same family, Onuphidae.

Aquabait understands the environmental implications of disturbing our delicate intertidal zones and estuaries, therefore by providing marine baitworms from our facility we can help to protect these areas and encourage the culture of marine worms in the future. Various ways that Aquabait has contributed to sustainability, both environmentally and economically are:

• by providing an alternate bait source other than from the natural environment to the recreational fishing market. 
• by providing a future protein source for aquaculture processed feed. 
• by the structural set-up of the farm that allows the out-flowing water from the farm to be treated and therefore, low in nutrient input into Lake Macquarie. 
• by the use of a waste product of warm water outflow from power generating facilities to increase year round growth rates.
• by identifying an industry within Australia that can develop into a basis for supporting Aquaculture and providing an open door to innovation through research.

Aquaculture is one of the fastest growing industries in the world. Sustainability is the buzz word of the aquaculture industry. The ultimate goal of aquaculture is to create a sustainable industry, meaning its impacts on the environment are negligible and the industry can continue to produce at a steady level indefinitely.

The intertidal zone of Australian and overseas estuaries have been the site of the bait worm industry for years. Delicate muddy shores and seagrass beds at low tide have been severely scarred from bait diggers. This type of environment takes many years to regenerate from this sort of disturbance (McLusky et al,1983; Olive, 1994; Van den Heiligenberg, 1987).

Three main types of exploitation can be recognised:

• Collection by anglers for their own use.
• Collection by semi-professional bait diggers for ad-hoc commercial sales.
• Collection by professional diggers contracted to wholesaler distribution.

The only worm farming that has existed previously was the earthworm farm that is now well known for its composting capabilities. The marine worm farm is a new concept completely different to earthworms. These marine invertebrates play a very important role in the food chain in the ocean and waterways. Many commercial fish require marine worms in their diet from a juvenile stage, and also at the adult stage of their lifecycle. Therefore, as it’s always the case, the small inconspicuous species are often forgotten about, but are always the most important link.

Studies of the population structure of exploited populations of bait worms suggest that only in relatively few areas are conditions suitable for a sustained fishery (Brafield and Chapman, 1967; Creaser et al, 1983; Olive, 1993). The value of bait worms in world markets suggests that these fisheries alone are not able to meet all the demand. By being able to cultivate marine worms in a controlled environment, the current recreational fishing market can utilise bait that has not caused any environmental disturbance (Olive, 1994).

The polychaeta (marine worms) play an important role in the ecology of marine communities partly due to the diversity of their structure and function. A relatively small number of species are also of commercial importance. This arises mostly from their use as live bait in support of the recreational fishing industry.

The polychaeta are likely to become increasingly important as a resource in relation to the development of aquaculture for Crustacea since it has been found that polychaetes can provide a nutritionally correct balance of polyunsaturated fatty acids which are essential for egg maturation in cultured prawns (Lytle et al, 1990) or can provide other factors essential for egg maturation (Croz et al, 1990). Currently there is valuable research being undertaken in the field of alternative live feeds in fish larvae (Kolkovski et al, 1997; Kolkovski, 2001).
A study in Western Australia, funded by the Fisheries Research and Development Corporation, is looking into the replacement of Artemia in marine finfish aquaculture based production for use as live larvae diet which weans the fish onto an artificial based diet (Kolkovski et al, unpublished, incomplete).

The development of marine worm aquaculture has the ability to provide marine finfish aquaculture farms the ability to obtain a live feed sustainably and affordably. Naturally in the marine environment polychaetes are an important source of nutrients for larval fish by providing them with certain digestive enzymes and fatty acids that are essential for growth and survival.

Aquabait Pty Ltd is the pioneer of marine worm farming in Australia and will continue to further research and develop the industry for important uses as mentioned. Aquabait is the first in the world to cultivate a species from the Onuphidae family, and continues to contribute to the scientific knowledge of the species farmed and inturn to polychaetes in general.

Aquabait Pty Ltd marine worm farm facility is a flow-through system in which water quality is continuously monitored. The farm has a total pondage area covering 1000m2. This is the pilot phase and is expected to triple over the next 2 years. Each pond has a sedimentary layer of sandy substrate which acts as a nutrient catchment and an ecosystem.
Natural breakdown of wastes and nutrients occurs within each pond as a result of bioturbation and recycling of nutrients by other small polychaetes, interstitial organisms, phytoplankton, microalgae and naturally occurring marine bacteria. This allows the nutrients from the tube-worm waste and leftover feed to be broken down within the pond before it leaves the facility.
Much of the nutrients and suspended solids that enter the ponds are taken into the system, therefore creating a filtering effect and allowing the water to escape back into Lake Macquarie “cleaner”. By the term “cleaner” I refer to there being low suspended solids, and insignificant traces of nutrients such as ammonia, Nitrogen, Phosphorus, Nitrates and Nitrites.

These findings are supportable by our water quality testing that is done monthly from both input and output, these results are then compared to reveal the levels entering the Lake Macquarie catchment. Aquabait has also built a separate pondage area that is strictly for the purpose of making sure the water output of the farm is maintained as “clean”. This pondage area is known as the settlement ponds. This pond creates a runway system before the water reaches the outflow pipes. This runway system allows the growth of macro and micro- algae to grow which takes up nutrients from the water and also catches any suspended solids. A pit is also integrated into this system to allow any escaping worms and loose sediment and feed to be caught onsite, then reused.

The Lake Macquarie City Council now requires zero nutrient input into Lake Macquarie catchment and Aquabait is very proud of its water quality results in support of this. This system utilised by Aquabait is again the first of its kind to produce such “clean” output from an aquaculture facility.

Aquabait Pty Ltd is positioned next to Eraring Power Station and currently utilises its inlet channel for its water input. Future developments will allow Aquabait to pump water from the outlet channel allowing the temperature of the water to increase and be more constant, therefore increasing the capacities of the farm to year round consistent growth rates.

This is an important use of the cooling water channel. A designated use for waste such as this can change the way power generating facilities are viewed in the future in that they will become increasingly sustainable, and supportive of projects such as this to also be viewed as sustainable.

There are large opportunities for an industry with polychaete worms in Australia, and overseas, not only for the recreational fishing industry but also for the aquaculture feed industry (Olive, 1999).

Aquabait Pty Ltd has developed its technology of spawning mechanisms, settlement and grow-out through sheer trial and error alongside scientific research. Aquabait is only in its beginning phase and much more research and development is under way. Aquabait’s leading technological advance in this industry will allow other marine worm farms to develop in the future with already developed technology to follow, and new technology to develop.

In order for the ever increasing aquaculture industry to remain and in some cases become sustainable both environmentally and economically, other facets of aquaculture production will also need to be sustainably produced, in this case aquaculture feed and fishing bait. Aquabait Pty Ltd has continued support from other polychaete scientists in Australia to advise on scientific aspects and a very supportive network through organizations such as NSW Fisheries for useful contacts with other aquaculture farmers and scientists and supportive advice, also Department of State and Regional Development for seeing a potential industry in marine worm farming and helping Aquabait with start up funding, also through Newcastle University, which is supporting our marine research scientist currently through a Masters Degree, and also to RIRDC (Rural Industries Research and Development Corporation), Rural Women’s Network and NSW Agriculture for recognising our research scientist as The Rural Woman Of the Year, for New South Wales, 2003.

Thanks to many of the supporting networks that exist in Australia for newly developing industries, it is possible for Australia to move ahead and promote the potential for Australians to succeed.

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