Hoki Fishery Has Too Many Environmental Impacts

The Forest and Bird Protection Society said today that the hoki fishery has too many environmental impacts to be assessed as a "sustainable fishery" by the Marine Stewardship Council (MSC).

Society spokesperson, Barry Weeber, said the hoki fishery had a widespread impact on the marine environment.

"1000 fur seals are killed a year in the hoki fishery and over 1100 seabirds are captured, 80% of which are killed."

Mr Weeber said albatross make up 60 percent of the birds caught, with white-capped, Buller's and Salvin's albatross being the main species.

"These three albatross species are listed as vulnerable threatened species by the Species Survival Commission of IUCN."

Mr Weeber said the fur seal deaths were impacting on a total New Zealand population of around 50-80,000 seals which is 5% of its population level in 1800.

"The latest information indicates a decline in fur seal numbers in colonies near the West Coast hoki fishery, which is consistent with the numbers being killed in this fishery."

Mr Weeber said there were also questions over the sustainability of hoki, in particular the eastern hoki stock.

"In the latest stock assessment there is a significant risk (60-70%) of the eastern hoki stock dropping below 20% of its natural population size in any year in the next 4 years.

Mr Weeber said the impact of the hoki fishery on other commercial and non-commercial fish species has not been adequately assessed.

"Also not assessed is the impact of this fishery on bottom dwelling species, many of which are long-lived and under increasing threat."

Mr Weeber said there clearly needs to be a review of the MSC procedures and Forest and Bird would be supporting a review of the accreditation of hoki.

"In our view hoki does not meet the requirements of MSC and the accreditation of this fishery should have been rejected."

For further information contact: Barry Weeber (04)385-7374 or (025)622-7369.

Background on Hoki Fishery

Hoki sustainability:

The latest Ministry of Fisheries stock assessment of hoki (Annala et al 2000) raises serious concerns about the sustainability of the eastern hoki stock.

The eastern hoki stock, which includes the Cook Strait and the Chatham Rise, meets the criteria of an "urgent sustainability" risk. The hoki fishery has for nearly 10 year been scientifically assessed as two stocks - eastern and western.

The latest NIWA assessment (two-stock MIAEL model) for the Ministry of Fisheries predicts that there is greater than 58 percent chance that the eastern stock will go below 20%Bo (the default danger level for any stock) in any year in the next 5 years. (When eastern CPUE is used the risk rises to 69%). The current biomass is estimated to be below Bmcy and above Bmay, which are proxies for Bmsy.

The current assessment states that "the current distribution of catches at the present TACC may cause the eastern stock to decline to unacceptably low levels". About 40% of current hoki catches are taken from the eastern stock. This stock is estimated to represent between 10 and 20% of the total hoki unfished biomass. From the assessment MCY is estimated at 28,000 tonnes and CAY1999 at 42,000 tonnes. These estimates of sustainable yield are less than half the current catch at around 100,000 tonnes.

More recent information is not optimistic. The 1995 and 1996 hoki year classes are weak. The January 2000 Chatham Rise trawl survey (the 9th annual survey) produced the lowest biomass of the 3+ year olds (half the lowest previous value). The 1 and 2 year olds were in the middle of the range indicating that the last 2 year classes are unlikely to be strong.

It is not a simple matter of switching 60-70,000 tonnes of catch to the larger western stock. This fishery is not without risk. CPUE based model results gives the risk of the stock going below 20% Bo in any year in the next 5 years as 23%. Switching catch would increase this risk. Length frequencies from this fishery indicates that over the last decade fishers are catching smaller fish, indicating an increasing reliance on younger fish and fewer year classes.

If more of the western stock catch was taken on the West Coast of the South Island additional complications arise:

* Fur seal deaths would likely increase from their current level of around 1000/year. This level of bycatch is neither acceptable nor sustainable. Surveys of West Coast breeding rookeries by DOC indicate a significant decline in pup numbers over the last 5-8 years. * Ling, silver warehou and hake over catch would increase. These three species have all had their catch limits in QMA7 exceeded due to the hoki fishery. Last year the hake catch was 2,200 tonnes over TACC (20%) and the ling catch was 1100 tonnes over the TACC (50%). Silver warehou TACC has been up to 45% over the TACC.

The west coast South Island hoki fishery has been associated with a catch of bycatch species exceeding the TACC for ling, hake and silver warehou.

Seabird Deaths:

The Hoki fishery has recently been identifed as a major cause of seabird deaths in the New Zealand EEZ.

An estimated 1100 bird caught by the hoki fishery, principally by flying in trawl wires. About 20 percent of the birds were reported released alive. The level of deaths could be higher as MFish observer coverage was often poor in months of high fishing effort.

The 1100 bird compares to 74 bird in the chartered Japanese longline fishery and over 1000 in the domestic longline fishery. The ling longline fishery is the other fishery which takes substantial numbers of seabirds. A range of species make up the species killed. Albatross make up 60 percent of the birds caught with white-capped, Buller's and Salvin's albatross being the main species - all of which are listed as vulnerable species by IUCN.

Fur seal deaths in hoki fishery

Fur seals are drowned in significant numbers in trawl nets in the West Coast hoki fishery. Between 1989 and 1998 (the most recent year for which data is available) over 5600 fur seals are estimated to have drowned in the West Coast hoki fishery and over 7200 in hoki fisheries throughout the EEZ.

The hoki fishery has had a high fur seal catch for over 10 years. The largest catch was 44 animals in one trawl net.

The total population of New Zealand fur seals is estimated at around 50,000 animals, around 5% of the population it was in 1800 prior to sealing in New Zealand waters. The populations of several fur seal colonies on the West Coast of the South Island have been declining in the last 5 years (Parliamentary Record 2001, Best pers com and Donoghue 1999). Female seals do not breed till they are around 5-6 years old. These colonies are adjacent to the West Coast hoki fishery.

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