Abalone

1. What is it?

Abalone (Haliotis midae) are endemic, slow-growing marine snails that take 8 to 10 years to reach legal fishing size making them susceptible to overfishing. Beginning in the late 1990’s /early 2000’s, abalone was subject to heavy fishing pressure (much of it illegal) which led to the eventual collapse of the stock. As a result, the commercial fishery was closed (February 2008) and then subsequently re-opened a few years later (July 2010) on condition that poaching is substantially reduced. In addition, biomass declines are also due to the southeast invasion of West Coast Rock Lobster (WCRL), which has indirectly affected abalone populations (DAFF 2014). The stock has continued to decline whilst poaching has increased by nearly 150%; as a result, abalone remains overfished and over-exploited.

2. How was it caught or farmed?

Abalone are farmed in a flow-through tank system on land which does not lead to freshwater depletion although the effluent water is discharged directly into the sea without prior treatment. The discharge is not considered a major concern at present. A number of farms are integrating seaweed culture with abalone farming which reduces final waste. Abalone culture requires feed inputs. Feed is consists of seaweed (wild-caught or farmed) and fishmeal and the majority of this feed can be traced to sustainable sources. The habitat alternation caused by farming abalone is minor. There have been no serious disease outbreaks recorded to date but this has occurred elsewhere and remains a potential threat to endangered wild stocks. Through good management disease, outbreaks can be detected early and controlled.

Abalone are fished by hand collection which is a highly selective process. Therefore, the amount of bycatch is low and often restricted to the organisms living on the shell. Diving for abalone causes no damage to the benthic habitat or benthic species. Some (minimal) damage may occur during low spring tides due to walking and dragging baskets over the benthic substrate.

3. Where is it from?

Abalone are farmed along the coast of South Africa. Although, broodstock are sourced from the heavily over-exploited wild abalone stocks, the collection of broodstock well regulated and controlled through permits. There are strict environmental impact assessments and a very good legal framework which addresses most the necessary concerns sufficiently.

The abalone fishery is managed through a TAC, which is set for each of the 7 commercial fishing zones. Management is not considered effective because of the severe poaching problem and continued allocations of commercial catches in severely overfished areas. Further, more resources and effort in terms of monitoring and compliance are badly needed.