SCS: New Zealand Sea Lion Mortality

At the end of January 1998 scientists working on New Zealand's sub-Antarctic islands found dead and dying New Zealand (Hooker's) sea lions (Phocarctos hookeri) on the breeding grounds there. This was the start of a serious mass mortality event which claimed the lives of at least 53 percent of the year’s pup production (over 1,600 pups), and which may have killed a significant percentage of the adult population. Unique to New Zealand, and the rarest sea lion in the world, there were an estimated 12,000 - 14,000 New Zealand sea lions before the mortality event.

On this page you can access news of the mass mortality by means of press releases, news wire stories and other information held locally and at other web sites on the internet. For some background information on the species see New Zealand Sea Lion. For information on New Zealand sea lion bycatch in trawl fisheries see Background: Sea Lions and Fisheries, part of a press release issued by the New Zealand Forest and Bird Protection Society. For the preliminary scientific report on the investigation of the mortality by the Massey University Cetacean Investigation Centre (MUCIC) and the N.Z. Department of Conservation see New Zealand Sea Lion Epidemic.

New Zealand Sea Lion Mass Mortalities
(31 Jan 1998, DOC Press Release)

A serious mass mortality event is currently sweeping through the two main breeding colonies of the New Zealand (Hooker's) sea lion (Phocarctos hookeri), with 30-40% of this year's pups already dead, and indications of increasing mortalities amongst adult females.

The New Zealand sea lion is found only in New Zealand waters and is one of the world's rarest seal species. In 1997, based on pup production estimates, the population was estimated at between 11,000 and 15,000 animals. Once distributed throughout New Zealand, from the tip of the North Island to Campbell Island, deep in the subantarctic, the species was taken to the brink of extinction by commercial sealers of the early nineteenth century. The major concern in recent times has been the impact of accidental catches in the trawl fishery for squid around the Auckland Islands, which is one of New Zealand's most important deepwater fisheries. For each of the past four years Ministers of Conservation and Fisheries have set a catch limit for sea lions. The squid fishery was closed early last year, because the sea lion catch limit was exceeded.

Over the past ten years, the Department of Conservation (DOC) has been monitoring the main breeding colonies of Dundas and Enderby Island, part of the Auckland Islands group located some 420km south of New Zealand's South Island. These two colonies (which collectively occupy an area roughly the size of six football pitches) account for some 95% of the sea lion breeding population. Annual pup production in recent years has been approximately 2,500 animals. Dundas Island is responsible for 80% of all pup production, but is surrounded by rocky reefs and is much harder to access than Enderby, where DOC has a research station.

DOC scientists arrived at Enderby Island in mid-January, and everything seemed to be normal. However, when weather conditions permitted a visit to Dundas on 26 January, the team discovered some 700 recently-dead pups. Symptoms included puffy eyes, ulcerated anuses and vaginas and lesions on the head. Dying pups often showed spasms and paralysis. Fewer adults than usual were on the beach, but at that time there were no signs that the older animals had been affected. Returning to Enderby, the team soon found that pups were beginning to die there also. In addition, adult females started showing signs of paralysis.

Afflicted animals also had small raised lesions on the belly and neck. Post-mortems have shown pus-filled swellings around the salivary gland in the neck. The most recent estimate on the day of this posting is that 111 pups have died on Enderby, and a further 150 are unaccounted for. 20% of the adult females on the breeding beach are dead or afflicted with lesions or paralysis. The numbers of adult females on the beach are considerably lower than normal. An unknown number of females (and males) may have died at sea, and some pups are consequently starving to death.

Samples from autopsied pups and females and six pup carcasses were flown back to the mainland by helicopter on 29 January. Pathologists from Massey University Cetacean Investigation Centre in Palmerston North will begin detailed examinations of the samples on Monday 1 February.

Mike Donoghue
Marine Protection
External Relations Division
Department of Conservation

Dozens of Hooker sea lion breeding cows may be the latest casualties of the mystery disease that is killing the endangered species in the sub- Antarctic Islands. Only 20 cows had returned after their normal two days at sea to feed pups on Enderby Island yesterday, when normally 150 should have been on shore. Department of Conservation spokesman Mike Donoghue said if the cows had died or were dying at sea it would be disastrous for the long-term recovery of the Hooker sea lion population which scientists fear may be already decimated by the disease.

Of the 350 to 400 pups normally on Enderby, scientists counted 111 dead and 150 were unaccounted for yesterday, he said. Nineteen percent of the adult population was also affected by the disease, which starts with lesions and progresses to paralysis before death.

Rough weather yesterday stopped scientists going to assess the situation at nearby Dundas Island where 80% of the Hooker breeding population lives. Seven hundred dead pups were found there on Thursday. Samples are being examined at Massey University, but it will be two weeks before any results are known.

The squid fishing season began yesterday amid criticism from the Forest and Bird Protection Society and Greenpeace. Squid fishing industry spokesman Andrew Branson said operators were told to be careful and watch out for sea lions. However he did not see why the season should be put on hold by what was happening to the sea lion population. "This event seems to be occurring by natural means. Fishing hasn't had anything to do with it". he said.

Under the Fisheries Act a specified number of accidental sea lion kills is allowed before the fishery is closed down. Last year it was 64. However, a figure hasn't been set for this season because of the disease. Last year, the season was closed early because too many sea lions were caught in nets.It was estimated $20m of quota was uncaught.

Wellington- Massey University scientists trying to find the cause of the deaths of hundreds of Hookers sea lions say while the present epidemic would dent the population, it was likely to recover over time.

Cetacean investigation centre director Per Madie said yesterday it was "highly unlikely" the entire population would be wiped out an organism because it would wipe itself out by killing off its host.But, he added, scientists were no closer to finding out that had killed the seal lions. The Department of Conservation said as many as 1000 adults and 1400 pups had been found dead in the Auckland Islands group, 320km south of New Zealand.

DOC public awareness co-ordinator for the Southland conservancy, Tom O' Conner, said the bodies of adult females were being washed up on the shore, making the situation more serious.

"For every dead female, that's one pup on the beach that starves," he said. Adult females were again pregnant so the embryos would also die if the females were struck by the mystery illness. Mr Madie said an autopsy of two pups had found a slight lung infection but that could be unrelated to the deaths. It was initially believed a virus might be responsible for the deaths but so far there had been no evidence to confirm that.

The team was now culturing tissue samples in the hope the micro-organism causing the deaths would become apparent. However, that was likely to take weeks. If the deaths were caused by a virus, the only remedy would be a vaccine, which could take years to develop.

Source: NewsRoom Tonight; Staff Reporter: Ian Llewellyn
Date: Thursday, 5 February 1998; Time: 10:21 pm NZT

Islands Closed - The Conservation Minister has closed the Auckland and Campbell Islands to visitors in response to potential risks to human health, from the mystery illness that has caused mass fatalities of New Zealand (Hooker) sea lions. See the Politics Wire. There is general concern that a series of environmental malaise may be linked. Besides the sea lions, dead marine life have been washing up on the parts of the eastern coasts of the Wairarapa and Kaikoura. In the Wairarapa a number of people and animals have suffered sore throats, headaches and irritations, these have been linked to algae at sea being blown on shore. Shellfish gathering has also been stopped on Great Barrier Island following the discovery of mussels contaminated with a natural toxin.

TV1 6pm News (first segment); Staff Reporter: Ian Llewellyn
Date: Thursday, 5 February 1998; Time: 6:15 pm NZT

1. Animals are dying and swimmers are falling ill around the coast of New Zealand. On Great Barrier Island people have been told to stop harvesting shellfish, on the Wairarapa Coast people are becoming ill and seals are dying on the Auckland Islands. The Conservation Minister has closed the Auckland and Campbell Islands die to the unknown nature of the mysterious ailment which is killing New Zealand sea lion pups.

2. Algae blooms are appearing around the coast causing problems for shellfish and other marine mammals in a number of areas. El Niño is being blamed.

Hot weather blamed for sealife deaths (6 Feb 1998, The Press News Page)

by Diane Keenan and Seth Robson (edited)

(Posted on the internet by Elayne Ravji (FOENZ) / <rabbit@wantree.com.au>)

The disturbing developments on the New Zealand east coast in the past week include:

[1] Reports of mysterious deaths of seals, crayfish, octopuses, and shellfish at Kaikoura.

[2] Toxic algae confirmed as causing health problems such as sore throats and nose and eye irritations in beach goers in the Wairarapa.

[4] Public health officials have closed the coasts of Great Barrier Island to shellfish-gathering after detecting a poison that can cause paralysis.

Bob McDavitt, of the MetService, said that the weather pattern of El Niño was a factor in the emergence of toxic algae in coastal areas. "We're going for the mother of all El Niños this summer, so it wouldn't surprise us if it also produced algae blooms."

Canterbury Health yesterday tested for algal bloom off the Kaikoura coast after reports of dead seals, crayfish, octopuses, and shellfish. The National Institute for Water and Atmospheric Research was taking samples from the dead octopuses washed up along the coast. Divers have reported dead kina (sea eggs) and crayfish off the Kaikoura Peninsula. Department of Conservation staff are investigating the Kaikoura reports. DOC Kaikoura field centre supervisor Mike Morrissey said two dead seals had been found near Kaikoura on Wednesday and tissue samples had been sent to Massey University for testing.

Further south, a seal separated from its mother was found at Waikuku, along with a dead adult seal. Mr Morrissey said there were about 3000 seals along the Kaikoura coast and some occasionally died of natural causes. However, the testing of the pair of dead seals was to ensure there was no connection with the dead New Zealand (Hooker) sea lions that were discovered last week at the Auckland Islands.

Mr Morrissey said he went diving off Kaikoura at the weekend and did not find any dead crayfish. "But I cannot think of any reason why kina would be lying upside down on the bottom unless they were suffering from an infection," he said.

Stress from hot weather killed an endangered adult female albatross and her chick at Taiaroa Head near Dunedin yesterday. DOC staff used fire hoses to spray nesting birds every two hours to keep them cool from high temperatures.

Squid Fishery Management Company Calls for Cessation of Fishing (23 Mar 1998)

Squid Fishery Management Company Limited
PRESS RELEASE - IMMEDIATE 2.00 PM
For All Agencies. 23 March 1998

The Squid Fishery Management Co Ltd today issued a circular on behalf of Shareholders in which all fishers were advised to cease fishing for squid in area 6 (near Auckland and Campbell Islands) immediately, and in any event no later than at Midnight on Monday 23 March 1998. The circular and call to cease fishing was made by the Company at 2.00 PM today on the basis that, by the best estimate available to the Company, the by-catch level for Hooker's sea lion had reached 63, being the maximum level permitted by the Minister of Conservation and the Minister of Fisheries.

Whilst continuing to debate a proper setting for any future sea lion by-catch limit, the Squid Fishery Management Co Ltd last week offered to Ministers an undertaking that it would take all responsible steps to ensure co-operation in monitoring the level of by-catch, and would act voluntarily to close the fishery at an appropriate time and thus avoid any over-run of the prescribed catch limit. In taking this voluntary but responsible action the Squid Company has shown its ability to monitor activities in the fishery and to take management action more promptly than the Ministry of Fisheries.

The Company has, of course, communicated its findings to staff at M.Fish and a legal closure of the fishery is expected to follow in a few days time.

The Chief executive for the Squid Fishery Management Co Ltd said today that initial indications from fishers has been that all those involved in the fishery will support the actions taken and observe the voluntary closure. For some it means a significant loss of revenue as a consequence of uncaught squid quota which cannot now be taken in the area, even though squid are expected still to be available in the area around the Auckland and Campbell Islands for at least another month. Squid fishing may continue, but only in area Squid.1, well away from the Auckland and Campbell Islands.

The Company has considerable concern for the status of Hooker's sea lion and has taken a number of steps to see that by-catch in the squid trawl fishery is minimised. The Company believes that it has only a very small impact on the aggregate sea lion population and that its activities do not endanger the population.

Unexpected high mortalities of sea lion pups and of some adults observed during January - February '98, well before squid fishing commenced, remain unexplained and the Company will continue its dialogue with officials from M.Fish and with DoC to consider further means for investigating the deaths and for monitoring the future sea lion population.

World Wide Fund for Nature has applauded the fishing industry's speed in stopping the squid fishery near the Auckland Islands, a move which was announced today.

"It is gratifying that industry has moved quickly to stop squid fishing in that area. We understand that as soon as it became apparent that the maximum allowable limit of sixty-three Hookers sealions killed had been reached, the industry took the initiative," said Chris Laidlaw, WWF-NZ's Executive Director. "Of course WWF has been strongly advocating closure of the fishery since January to protect the sealions. Over 1600 have died from illness and losing any more from fishing activities compounds the tragedy. However, by moving quickly, the industry has ensured that no more unnecessary deaths will impact on this rare species this season."

Mr Laidlaw also said that the decision to stop fishing is a clear example that industry can move quickly on conservation matters when necessary and it showed how important a maximum allowable limit had become to the survival of the sealions.

According to Mr Laidlaw there has been intensive interest in the Hooker's sealion situation, both in New Zealand and overseas. "We are aware of a number of overseas groups who have been monitoring the situation very carefully. We are pleased that the New Zealand industry has made the right move and not tarnished our standing in the international conservation arena."

The squid fishing industry says millions of dollars in squid exports and many jobs could be lost with the early closure of part of the squid fishery. The chief executive of the Squid Fishery Management Company, Andrew Branson, says they closed the Auckland and Campbell Island fishery because the quota of 63 allowable sea lion deaths had been reached.

The Squid Fishery Management Company is a fisheries industry organisation, which manages the fishery on behalf of individual quota owners. The closure follows Greenpeace claims that the rising death toll of Hookers Sealions in the fishery was pushing the world's rarest Sealion nearer to extinction.

By regulation, the Minister of Fisheries sets the maximum number of allowable sealion deaths from fishermen's nets. This number was reduced after a mass Sealion die-off in February killed 60 percent of the pup population and at least 20 percent of the adults.

Mr Branson says many boats are a long way from catching their full quota since the season started only in February, because of the mass deaths in the sealion breeding areas. The season usually runs from December to April or May. The Auckland and Campbell Islands area provides up to half of the country's squid exports, which are worth between $120 to $160 million a year. More than two thousand crew work on boats in the area, and 175 full-time staff process the squid year-round. Mr Branson says it is likely that some of the jobs will now be lost.

Forest and Bird Protection Society said today it was disappointed that 63 New Zealand Sea lions had to die before the Auckland Islands squid fishery was closed.

Society spokesperson Barry Weeber said the fishery should never have opened this season once the seriousness of the mystery disease impacts on sea lions was known.

"We still do not know what the disease was or what the final impact has been on adult sea lions. In similar disease events overseas as many as 60-70% of adult sea lions have died."

Mr Weeber said that reports from Ministry of Fisheries observers on fishing boats indicated that the disease was continuing to cause harm as animals with neck lesions were still being seen in the water. Neck lesions is one of the signs of the disease which affected the sea lions.

"Since the squid fishery started in the early 1980s over 2000 sea lions have died. Squid fishing has drowned the most seals but it is not the only fishery that has killed sea lions - they have also been drowned in the scampi and orange roughy fisheries around the Auckland Islands."

Mr Weeber said the fishing industry were over-playing the economic aspect of any closure. The Auckland Islands squid fishery catch has been very variable with an average of only 56 percent of the allowable catch limit being caught in the last 11 years.

"In 1993 only 5% of the catch limit was caught. In the last 11 years the fishery has been closed due to sea lion deaths only in the last two years.

Mr Weeber said the scampi and orange roughy fisheries should also be closed around the Auckland Islands. Both fisheries were considered to be unsustainable with declining catch rates.

"It is urgent for the Ministers of Fisheries and Conservation to develop a management plan to deal with Auckland Islands fisheries. This must include extension of the current marine mammal sanctuary out to 100 kilometres off the Auckland Islands.

Mr Weeber said the industry must consider using alternatives to trawling for catching squid. Jiggers which catch squid elsewhere should be trialed around the Auckland Islands."

Note: Jiggers use bright lights and a barbed hook to catch squid. The method has little by-catch of other fish species and is used in other parts of the fishing zone to catch squid.

No killed in previous years?
Since the Auckland Islands squid fishery began in 1979 around 2000 Hooker’s sea lions have been estimated to have been drowned. Squid is caught in nets 60 m high and over 150 metres wide which are towed by large trawlers. Ministry of Fisheries (previously MAF) have only had consistent observer coverage since 1988. In the last 10 years over 775 sea lions have been killed. Sea lions have also been reported drowned in the orange roughy, scampi and southern blue whiting fishery around the Auckland Islands.

Year	Mortalities	Agreed Limit
1988	33
1989	141
1990	117
1991	21	16
1992	82	16*
1993	17	63
1994	32	63
1995	109	63*
1996	101	63
1997	123	73
1998	63+	63 was 79

Hooker’s or New Zealand Sea lion?
Hooker’s or New Zealand sea lion (the names are alternates) only breeds around the New Zealand sub-antarctic Islands. The population is estimated at around 11,000 to 15,000 animals prior to the recent mass die-off. Of these, 95 percent breed on two small islands off the Auckland Islands - Enderby and Dundas Islands. Dundas Island, where 75 percent of the animals breed is only the size of two football fields. A small population lives around Campbell Island and occasional vagrant pupping occurs on Snares Islands.

The population may have been reduced by between 20 and 60% in the recent disease event. The actual extent of mortality of adults will not be known for 1 to 3 years.

Hooker’s sea lions were killed for pelts by sealers in the early 1800s and reduced to very low levels. It is likely that the population has not yet recovered to pre-European levels. Evidence indicates that Sea lions bred in the Nelson area and on the Chatham Islands in the last 1000 years but were eliminated by Maori harvests.

The seal specialist group of the Species Survival Commission (a group of 7000 international specialists) of IUCN - the World Conservation Union, ranks Hooker’s sea lion as a vulnerable threatened species. This ranking is based on objective criteria which have been developed over the last 10 years after extensive international peer review. These criteria are now internationally recognised. In October 1996 IUCN published a Red Data Book containing all threatened animals ranked by IUCN specialist groups.

According to the Red Data Book, the new criteria "applie[s] a more objective system for classifying conservation status, that allows comparisons to be made across species in assessing the likelihood of extinction". The new criteria provides for:

The Minister of Conservation has gazetted Hooker’s sea lion as a threatened species under the Marine Mammals Protection Act. This was opposed by the fishing industry.

Sea lion Limits:
1998 is the sixth season limits have been in place on the number of sea lions that can be drowned in the squid fishery before it is closed. The limits are agreed by the Ministers of Fisheries and Conservation after consultation with all stakeholders.

In 1996 the limit was 63 sea lion deaths or 32 female sea lion deaths. Last year the Minister of Fisheries agreed to increase the limit to 73 sea lions. This year the limit has been raised again to over 79 sea lions before Ministers reacted to the deaths caused by the disease and reduced the limit by 20% to 63.

Forest and Bird has consistently proposed a much lower limit with the aim of reducing mortality towards zero.

Legislation:
The mortality of Hooker’s sea lions in fisheries is managed by the Fisheries Act and the Marine Mammals Protection Act. Since 1 October 1996 new provisions were added to the Marine Mammals Protection Act which allow the Minister of Conservation to develop a Population Management Plan for protected species at risk from fisheries. Consultation has occurred with all stakeholders, and several technical meetings have been held. The Department of Conservation intends to finish this plan prior to the opening of next year’s squid fishery. This plan includes setting a limit for the number of sea lions that can be drowned in fisheries.

The Fisheries Act 1996 has new provisions to control the by-catch of protected species - both marine mammals and seabirds (section 15). Under section 15 the Minister of Fisheries must apply the limit agreed in the population management plan or if there is no plan, the Minister must set a limit under sub-section (2). The Minister has an obligation under section 15(5)(b) "for the purpose of ensuring that any limit on fishing-related mortality is not exceeded" (our emphasis).

To achieve the requirements of the Act the agencies have to establish a process which will ensure that the limit is not exceeded. Despite repeated requests no such process has been established and the limit has been well exceeded for the last two years. A population management plan for Hooker’s sea lions is proposed to be released later this year for public consultation.

Industry code of practice
The industry has developed a voluntary code of practice for marine mammal interactions. The code includes a provision that any vessel which catches three or more sea lions will be removed from the fishery so that a review can be undertaken. Last year two vessels caught three or more sea lions, with one vessel catching more than seven. None of these vessels were removed and no review was undertaken. The industry breached their own code of practice, further bringing into question the effectiveness of the code.

Squid Fishery
The squid fishery is a very variable . Squid only live for about a year before spawning and thus the number of squid present every year is mainly dependent on environmental conditions. In the last 10 years the reported catch in the fishery around the Auckland Islands has varied between 1551 tonnes and 34,534 tonnes. The current catch limit is 30,369 tonnes. Squid is caught mainly by chartered Russian, Japanese, Norwegian, Korean and Chinese vessels fishing for New Zealand companies.

In 1996 only 14,041 tonnes had been caught by the time the fishery closed in early May. The fishery usually runs from the beginning of February to the end of April. In 1997 the fishery started earlier, in the middle of January. An estimated 19,843 tonnes were caught last year, which is greater than the catch for seven of the last ten years.

The Auckland Islands squid fishery represents 25 percent of the New Zealand squid fishery, which has a total catch limit of 123,332 tonnes. On average 25 percent of the squid catch comes from the Auckland Islands.

The sustainable catch limit for squid in any of the New Zealand squid fisheries is not known. Research into the squid ceased in 1993 and the current catch limits are arbitrary. The squid fishery is managed under the Quota Management System. While squid are part of the sea lions diet this was not considered when setting the catch limit.

The fishery was closed in 1997 at the end of March by the Minister of Fisheries when 123 sea lions had drowned which was well above the agreed limit of 73. This is the second consecutive year the fishery was closed early because of Hooker’s sea lion deaths.

Stock No.	Year	TACC	Rep Catch	Catch/TACC	Sealion Deaths
SQU6T	1986-87	32333	16025	50%	143
SQU6T	1987-88	32333	7021	22%	33
SQU6T	1988-89	35933	33462	93%	141
SQU6T	1989-90	42118	19859	47%	117
SQU6T	1990-91	30190	10658	35%	21
SQU6T	1991-92	30190	10861	36%	82
SQU6T	1992-93	30369	1551	5%	17
SQU6T	1993-94	30369	34534	114%	32
SQU6T	1994-95	30369	30683	101%	109
SQU6T	1995-96	30369	14041	46%	101
SQU6T	1996-97	30369	19843	65%	123
SQU6T	1997-98	30369
Average		32109.25	18048.91	56%	83

No Cause Found for NZ Sea Lion Die-Off
(30 Apr 1998, DOC Press Release)

The cause of the die-off of New Zealand sea lions in the subantarctic in January and February this year has not been determined, despite extensive study of samples from diseased animals in New Zealand and overseas. Laboratories at Massey University (Palmerston North), AgResearch (Ruakura), Environmental Science and Research (Porirua) and Erasmus University (Rotterdam, The Netherlands) have examined samples of tissue and blood for an infectious agent or toxic residues over the past three months without a definitive result. The United States' Department of Agriculture's Foreign Animal Disease Diagnostic Laboratory in New York is currently undertaking final tests for viruses.

DOC spokesperson Dr Alan Baker says scientists have reported that there are two possible scenarios for this mortality event: "One possibility is an infectious agent, such as a virus or bacteria, spreading rapidly through the crowded colonies, causing sickness and death. The second possibility is that poisoning or impairment occurred, caused by a marine biotoxin or 'red tide'. Sea lions could succumb after ingesting such a toxin or inhaling toxic aerosols in ocean spray."

Dr Baker said that although it was unlikely that bacterial infection, such as the Salmonella species isolated from diseased samples, was the cause of the epidemic, their role as a cause of death in some animals is under further investigation. Salmonella was also isolated from samples of sea lions collected a year before the epidemic. The isolation of these bacteria from New Zealand sea lions therefore may be an incidental finding. No viruses have been isolated from the samples.

"If infectious agents cannot be implicated as the cause, a possible alternative is intoxication by a marine algal biotoxin acting alone or in combination with alterations in prey availability or distribution caused by El Niño. No biotoxin has been identified in the samples collected to date; however, biotoxins are notorious for leaving no residues, and their absence may also reflect the lack of suitable samples. For example, no water samples or plankton samples were able to be collected from the Aucklands shelf waters at the time of the epidemic. Neither was it possible to collect samples from sea lions that died at sea."

Dr Baker said that there was a possibility that an algal bloom occurred in the Auckland Islands region during January 1998. "Landsat imagery, provided by the NZ National Institute of Water and Atmospheric Research (NIWA), shows high chlorophyll concentrations in surface water layers around the Auckland Islands in January. However, it is not known whether this phenomenon is a regular or a rare occurrence in that remote subantarctic region. Coincidentally, there were red tides at other locations around the New Zealand mainland between January and March that caused clinical illness in people and was the likely cause of fish, sea bird, and fur seal deaths in those affected areas.

"A possible scenario for the event is that if sickness or death, either pathogen or biotoxin-induced, resulted in longer or ineffective foraging sorties, or even none, then at least some pups would suffer malnutrition and be predisposed to secondary bacterial or parasitic infections that would otherwise be harmless. The "podding" or huddling behaviour of pups on the beach could also facilitate the rapid spread of pathogenic bacteria between animals."

Work on existing samples of sea lions would continue, and a winter expedition to further sample the subantarctic population was proposed, said Dr Baker. A scientific workshop would be held in Wellington in June to review the research into the sea lion die-off.

Please see the Massey University website at "www.massey.ac.nz" for a full copy of the scientific report, and for further information, contact Dr Alan Baker, DOC Science & Research Unit, phone: 04 471 3299, or Nicola Patrick, DOC Public Awareness Unit, phone: 04 471 3117.