Cracking the code to farming rock lobster
One of the benefits of studying marine biology at Deakin University is the range of successful graduates Deakin can call on to give guest lectures during the semester.
David Francis, who completed the undergrad through to PhD route in aquaculture at Deakin, has been part of a team at the Australian Institute of Marine Science in Townsville, Queensland looking at developing a stable program of rearing farmed rock lobster (crayfish).
The growing and increasingly lucrative market in Australia (and for export) for rock lobster and its impact on wild stocks has understandably concerned crayfishers, fisheries bodies and marine scientists.
Many varieties of rock lobster have low fecundity, larval survival rates and long larval stages (the southern rock lobster Jasus edwardsii has an average larval (phyllosoma) stage of 450 days, while the tropical variety Panulirus ornatus has only 150 days as larvae). Illegal fishing – including licensed crayfishers flaunting size and catch restrictions – has further decimated wild stock numbers in several main fishing grounds.
Apart from the difficulties and expense of farming a species with a long larval stage, Francis’ team also found that creating the right feed formulation was a tough task – larval lobster are notoriously picky and cannot survive on a standard fishmeal diet, so creating the perfect feed became the AIMS team’s key goal.
After investigating the gut contents of wild prey and chemical profiling the tropical lobster larvae, the AIMS scientists were able to formulate a growth-focused feed to take the larvae successfully into the juvenile stage.
Restrictions on funding meant the research has not yet been completed but Francis hopes an aquaculture company can continue to invest in the program and raise a commercial quantity of farmed lobster, helping in the long term to reduce the impact on wild fisheries.