Category Archives: Fish Stocks

Amorous roughy respond to fishing

16th August 2013

A scientific paper (Pitman, Haddy and Kloser) has been released assessing the impact of commercial fishing on the reproductive capacity (fecundity) of orange roughy. Data from when exploitation began (1987–1992) is compared with current observations from the eastern Tasmanian stock. Findings show that fecundity is negatively related to stock size, meaning that as the population of orange roughy declined fecundity per individual increased 41,145 (± 1,363) eggs in 1992 to 59,236 (± 1,047) eggs in 2010. The fecundity per fish has increased by 73%. Modelling this increase based on the 2006 stock assessment showed that the female spawning stock biomass was at 19% of virgin levels, whereas the total reproductive potential was markedly higher and estimated to be at 32% of virgin levels. The biological mechanisms of this compensatory effect were also investigated and showed fecundity was not related to ovarian atresia levels but was positively related to body condition and liver condition. The implications of these findings for stock recovery and management suggest that the stock is in a better position to recover from over-exploitation than would be expected if only spawning stock biomass is considered. The full report can be read here.

Fishermen collect 2,000 blue warehou lengths

7th May 2013

In 2011 industry began to collect length data on blue warehou during the SETFIA run blue warehou fishery independant survey.  The aim of the collection is that the information could be used in a future stock assessment. Industry avoids blue warehou in an effort to allow it to rebuild but in doing so has lost the use of catch as an index of abundance.
In 2011/12 Ray Wicks and his crew from Portland were awarded the prize for the collection of the most blue warehou data. In that year industry collected information from 2,070 fish.
The 2012/13 award has been won by the Skipper and crew of the Lady Miriam – a trawl vessel domiciled in Lakes Entrance. For their good work Skipper Trevor (Bluey) Hunt and his crew have collected the most data collecting 1,961 lengths. For their efforts each has won themselves a Prime Mover Workwear water repellent jacket.
The Association is hopeful that the data individually collected from 4,000 blue warehou might contribute to an SPR assessment. Now that an SPR assessment might be a reality SETFIA hopes to really ramp up the collection of data.

Quotas in the South East increase 600 tonnes

23rd April 2013

The Australian Fisheries Management Authority (AFMA) have stated that increasing productivity of wild fish stocks has allowed an increase in the sustainable seafood harvest catch limits for a number of key species in the Southern and Eastern Scalefish and Shark Fishery (SESSF). The South East Trawl Fishery is part of the SESSF.
Catch limits for popular table fish such as flake and whiting have increased in the 2013/14 fishing season following scientific advice showing stocks are healthy and increased catches can be sustained.
The fishing season opened on 1 May 2013 with the total allowable catch limits increasing for 11 of 34 species, including Gummy Shark, Silver Trevally, Mirror Dory and School Whiting and catch limits for most other species remaining stable.
There will be a net increase in the aggregation of Total Allowable Catch (TAC) limits this season of more than 600 tonnes, which is great news for the fishing industry and seafood consumers.
AFMA CEO Dr James Findlay said that this was a pleasing result with strict management and world leading science ensuring the sustainability of our fisheries for years to come.
“The overall improvement in fish stocks is a result of strong science-based management and an industry dedicated to the long-term sustainability of the fishery and their business. Ultimately this means more fresh, sustainable, local fish on Australian tables and more fishing jobs in rural and regional Australia”.
AFMA has also recognised the significant contributions that all members of its Management Advisory Committees and Resource Assessment Groups, as well as stakeholder bodies, have made to sound fisheries management over many years.

Will SPR analysis help assess blue warehou?

22nd April 2013

An Australian breakthrough in stock assessment science looks to solve the problem of assessing data-poor fisheries and make assessment processes affordable. The approach estimates the proportion of spawning occurring relative to unfished levels rather than estimating sustainable catch levels directly, simply indicates whether fishing pressure should be incrementally increased or decreased until stocks and catches stabilize at management targets. The technique makes assessment possible with information about average maximum size, or size of maturity, and current size composition. Eliminating the need for information about stock structure, catch rate trends and biomass estimates the new approach promises to slash the cost of fisheries assessments worldwide.

Blue warehou is one of the three stocks (of more than 30 commercial stocks in total) in the fishery with a quota set that only allows unavoidable by-catch.  No targetting is allowed until the stock rebuilds.  Industry has worked to avoid blue warehou and CSIRO confirms that an analsysis of the fishery shows less and less targeting.  However, no targetted fishing means that it is very difficult to assess the stock’s abundance.  Thousands of length/frequencies collected by industry, the observer program and on previous fishery surveys may have the potential to feed into a future SPR analysis and provide a trend in abundance.

For more information on SPR analysis contact Dr Jeremy Prince.

Australia’s fish stocks in great shape

5th March 2013

In December 2012 the Australian Government released the first ever national snapshot on the status of all major Australian commercial fish stocks. The report found that Australian fisheries are healthy and well managed. Only a tiny fraction of the 150 stocks reviewed were found to be “overfished”.
The report was compiled by the Australian Bureau of Agricultural and Resource Economics and Sciences (ABARES) and took 80 scientists 18 months to compile before being peer reviewed. The 150 stocks reviewed cover 70% by volume and 80% by value of the Australian commercial fishing industry regardless of whether they are managed by a State or the Commonwealth Government. The full report is available here.
98 stocks are classed as “sustainable”, 11 “transitioning”, 39 generally smaller stocks had insufficient catch and therefore insufficient data to have them assessed and only two stocks were found to be “overfished”.
Mr Tom Bibby, the South East Trawl Fishing Industry Association’s (SETFIA) Chair said, “This is a report for all Australians, for consumers, for sellers, for fishermen and for researchers. It is the first ever broad and independent review of the status of Australian and probably global commercial fish stocks. We are overjoyed that it has found that Australian fish stocks are in such good shape.”
The two species found to be overfished are school shark and southern bluefin tuna. Both species are already subject to strict management controls and are rebuilding. The South East Trawl fishery does not catch southern bluefin tuna and school shark is managed as part of another fishery.
Mr Bibby concluded by stating that, “This report confirms what the fishing industry has known for a long time. That is that Australia’s fisheries are well managed and there will be fish for generations to come. To make a sustainable choice all consumers need to do is to buy Australian.”

A better solution for unavoidable snapper by-catch

5th March 2013

Snapper is an iconic recreational species with around 550 tonnes caught annually by Victorian recreational fishermen. Fisheries in Australia are managed either by the State or the Commonwealth. In waters adjacent to Victoria, non-trawl caught snapper are managed by Victorian but snapper caught by trawlers are managed by the Commonwealth. South East Trawl (SET) vessels have a long history of taking a small amount of snapper as a by-catch. The Australian Fisheries Management Authority (AFMA) imposed what is known as a trip limit above which all snapper must be returned to the sea dead. Snapper do not understand that fishing vessels are licensed either by the State or Commonwealth and are sometimes caught by Commonwealth vessels and dumped dead. A trial promoted by SETFIA in eastern Victoria put strict move-on conditions on SET vessels if they catch snapper but also allows for all unavoidable by-catch to be landed rather than thrown away dead. The trial saw SET catches fall from 100 tonnes to about 50 tonnes per annum currently. The trial was agreed by all stakeholders a a success but AFMA and Victoria are yet to agree a management arrangement and SET vessels continue to be forced to dump snapper. The Association continues to call on AFMA to adopt the move-on arrangement which worked so well and did not waste any snapper.

Monster pink ling

4th March 2013

Crew member Richard Knox couldn’t believe his eyes when this massive pink ling was hauled on board the Petuna Endeavour. The average pink ling is 1m long and weighs less than 10 kg’s. The maximum reported weight for pink ling is 25 kg’s at which time it would be 30 years old. However, the pink ling pictured weighed a whopping 45 kg’s and was 1.74m long. Pink ling live along the southern coast of Australia, from Perth to Port Macquarie including Bass Strait and around Tasmania, in open waters on the continental shelf and upper slopes between 200m and 800m. They occur in other southern hemisphere countries including New Zealand, Argentina and Chile. Many fishermen believe that ling live in burrows when on soft bottom but they are also often associated with canyons. Pink ling is an important commercial species in Australia and are managed under quotas set by the Commonwealth harvest strategy.

Industry manage eastern gemfish

4th March 2013

Prior to management under the Harvest Strategy, eastern gemfish were depleted in southern NSW when in the 70’s and 80’s when catches were as high as 7,000 tonnes a year. Eastern gemfish spawn in June, July and August and most by-catch is taken in winter as the fish undertake their spawning run on NSW’s south coast. Eastern Gemfish was listed as conservation dependant in 1999 and the Harvest Strategy now allows no targeting.
It is therefore important that they are actively avoided as much as possible to allow them to continue to rebuild. The code of conduct agreed by fishermen from Sydney, Wollongong, Ulladulla and Eden included measures such as:
1. Communicating each day with other vessels within 20 miles in gemfish season
2. Steaming away deeper or shallower if more than a third of the catch in a shot is gemfish
3. Contacting the Association if they catch more than 20 boxes in a single shot. A warning with co-ordinates is then sent to the fleet
4. Using special gear including larger meshes to allow juvenile gemfish to escape
5. Leasing quota out to other vessels (who need to cover unavoidable by-catch), rather than targeting any quota remaining at the end of the season
The Association is pleased to announce now that the fishing year is finished that the 2011/12 catch of eastern gemfish was 76 tonnes even though there is a 100 tonne by-catch quota allowed. These by-catches are much lower than those of the previous three years which have been 119 tonnes, 100 tonnes and 108 tonnes. This year’s lowered take will speed up the recovery of the species.
Mr Tony Lavalle, SETFIA Director and Ulladulla fishermen explained, “Fishermen have shown that they can avoid this species and the Commission have agreed to leave the by-catch quota at 100 tonnes. We may catch a little less or a little more this winter but will continue to work to the code of conduct to avoid gemfish. The current 100 tonne quota should be sufficient to see no dumping of unavoidable fish.” He added, “This success has shown that there are ways to manage fisheries without more closures”.

Commonwealth fish stocks continue to improve

14th February 2013

The Australian Bureau of Agricultural and Resource Economics and Sciences (ABARES) has released the 17th edition of Fishery Status Report (2011). This annual report is similar to the ground breaking national snapshot report released in December but the latest Fishery Status Report covers all fish species managed by the Commonwealth Government (not those managed by the States and not just the economically important species).

The latest report found that the number of Commonwealth stocks fished at a sustainable level has increased from 71 to 77. The number of stocks subject to over-fishing has decreased from eight to six. The number of stocks whose status is uncertain has also decreased from 17 to 12.
These findings are consistent with the national snapshot of both Commonwealth and State managed species which also reflected very positively on Australian fisheries.
The situation in South East Trawl Fishery has improved from an already strong position. Previously four of the 28 species in the South East were assessed were classed as being subject to over-fishing but this has reduced to two with only eastern gemfish and gulper sharks remaining in the “red”. Gulper shark catch is now almost nil with 30-40% of gulper habitat closed to trawling. Eastern gemfish by-catch was the lowest ever in 2011/12 due to active avoidance brought about by a code of practice and training courses for fishermen which raised awareness of the need to avoid the specie and let it rebuild.