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Estimating recreational catch in Tasmania’s rock lobster and abalone fisheries

Rock lobster and abalone have always been an important food source for Aboriginal people in Tasmania and are highly prized by recreational fishers as well as supporting major commercial fisheries.

Participation, fishing effort and catches in Tasmania’s recreational rock lobster and abalone fisheries have been relatively consistent across recent seasons, according to the 2018-19 fishing season survey conducted by IMAS.

Both fisheries have been regularly monitored since the mid-nineties and moved to annual surveys in 2014 focusing on the fishery off the east coast.

This followed the East Coast Stock Rebuilding Strategy implementation in 2013, which aims to rebuild east coast rock lobster stocks to at least 20% of the unfished biomass by 2023.

Taking notes on catch and effort

During the 2018-19 season, more than 18,000 people held at least one recreational rock lobster licence and over 11,000 held a recreational abalone licence, an increase of around 5% compared with the previous licensing year.

For the survey, a random sample of licence-holders were invited to provide details of their rock lobster and abalone fishing activity between November 2018 and April 2019. The survey achieved an 80% response rate, with almost 500 respondents providing detailed catch and effort information for each of their fishing trips. This information was then scaled up to represent the entire fishery.

AbaloneThe state-wide rock lobster harvest for the survey period was estimated at over 70,000 lobsters, equivalent to 74.7 tonnes. Catches from the east coast of Tasmania accounted for 78% of the total harvest by number and 72% based on weight, with the remaining harvest split between the north and west coasts. (Images: left, credit Scott Ling; above right, credit Antonia Cooper)

Over 60% of rock lobsters were taken by potting and 37% by dive collection, with ring nets accounting for only a small proportion of the total catch. Average daily catch rates achieved by divers (1.7 lobsters) were, however, substantially higher than those for potters (0.7 lobster).  

Divers targeting abalone were estimated to have caught almost 45,000 abalone in 2018-19, with Blacklip abalone dominating the catch at almost 80% of numbers and Greenlip abalone accounting for the balance.

About one in five dives resulted in the daily bag limit (10 abalone in 2018-19) being taken, with the overall average daily harvest rate at 4.5 abalone. The current Abalone harvest estimate of about 21 tonnes is very similar to those for the previous three seasons, which are also among the lowest since surveys commenced.

Making moves to rebuild east coast rock lobster stocks

Declining rock lobster stocks were identified in the late 2000s and hit historically low levels in the 2011-12 due to years of below-average recruitment and heavy fishing pressure. In response, the East Coast Stock Rebuilding Strategy was developed.

A key element of the strategy is an east coast recreational catch share target, set at 40 tonnes for the stock rebuilding zone in 2018-19. Recent management changes, including reducing the eastern region bag limit to two lobster per day and shortening of the season, have been implemented to help constrain recreational catches to within catch target levels.  However, despite these measures it is proving more and more challenging to constrain recreational catches to target levels, especially as stocks rebuild and catch rates improve (see table).  In fact, the only seasons where catches have been below target levels (2015-16 and 2017-18) were those heavily impacted by biotoxin closures during peak fishing times, resulting in a marked reduction in recreational fishing effort.

E. Coast stock rebuilding zoneThe IMAS Tasmanian Recreational Rock Lobster & Abalone Fisheries 2018-19 Fishing Season Report includes estimates of catch and days fished by fishing methods and area, and social information including attitudes about perceived stock status, fishing quality and management. Read the full report here.

Authorised by the Executive Director, Institute for Marine and Antarctic Studies
December 2, 2019