Environment

Mass oyster mortality in Manihiki
Muri supports sanitation plan
TIS calls for shark finning ban
Fishing groups review concerns
CITC gives cameras for turtle expedition

Dead pearl oysters on spat collector lines – dead jewel box shell at 30m. 12030527

Graph of Temperature and Dissolved Oxygen profiles of Manihiki lagoon. 12030526

Pearl farmers have often described previous “dark periods” in Manihiki lagoon. The current dark state of the lagoon however is just part of the picture involving the complete mortality of all bivalves, including pearl oysters, below 25 metres in the Manihiki Lagoon.

The culprit is thought to be La Nina weather conditions, according to Ministry of Marine Resources (MMR) pearl biologist Georgia Langdon, who presented her findings from a survey of the lagoon to the Island Council and pearl farmers of Manihiki.

“What we have is a combination of unfavourable lagoon conditions that have stressed the oysters for a prolonged period of time. Unusually cold weather in January 2012 may have been the final straw triggering this mass mortality event,” said Langdon.

The trigger for alarm was mass numbers of dead shells on spat collector lines that had surfaced. Scuba surveys have confirmed all pearl oysters wild or farmed, kuku, pipi, kapi kapi and jewel box shells below 25 metres had recently died. All sites surveyed indicate that the mortality is a lagoon wide phenomenon.

Previously dark periods have lasted just weeks but the lagoon has been ‘dark’ since winter 2011, with extraordinarily high levels of chlorophyll indicating an intense algal bloom is occurring.

It is thought that the unusually intense La Nina conditions during the 2011 winter, resulted in a stratified layer of cold dense water sitting below 15m in the water column. This stratification is likely due to a lack of wave driven flushing of ocean water through the lagoon.

Also of serious concern are dissolved oxygen levels at 25m depth which dropped below acceptable levels of 4mg/l.

The concern of MMR now is the that the lagoon does not experience a rapid “turnover”, which would bring all the stagnant water and particulates up from the bottom, causing poor water quality at the surface.

The ministry is putting in place a monitoring survey to profile lagoon water quality and pearl oyster mortality checks.

Fortunately there is currently a team of scientists from Queensland University who are on the island to model lagoon flushing.

“This is not to be confused with the conditions experienced during the 2000 disease outbreak. That was a time of El Nin conditions with very hot, windless weather and high stocking densities leading to massive mortalities of pearl shell on the surface layer.” says MMR secretary Ben Ponia.

There are pearl farm management implications for farmers and the MMR is urging farmers to ensure that their farm lines are kept afloat at the recommended depth of 6 meters. Farmers are also urged to clean their shells regularly and remove old farm lines and unused structures from the water. The accumulation of bio-fouling organisms on these structures heavily contributes to the increased oxygen demand from the water.

These measures have the support of the Manihiki Island Council and the Mayor Ngamata Napara has urged farmers to adopt the Manihiki Pearl Farmers Lagoon Management Plan.

There is no previous report of a dystrophic event of this scale in the 30-year history of pearl farming in Manihiki, but it is expected that the surviving populations of bivalves will eventually repopulate the lagoon.

The MMR team is working with other scientists in the region to see if similar events are taking place elsewhere.

• SMR/RS

Organisers are saying that a public meeting on Muri Lagoon water quality was a success after 45 local residents turned up on Thursday night.

Water Waste and Sanitation Unit (WATSAN) project director Ken McDonald said the response from the local community had been really positive.

“Given we are working with 239 houses, to have a response of 40 to 50 people is really good. If they are representing even one-in-six houses, that’s a pretty good result.”

The meeting was organised to inform Muri locals of plans to upgrade the sanitation units of 239 houses. The project is part of an ongoing programme supported by the New Zealand Aid Programme to improve the quality of Muri lagoon. The project will cost about $2.4 million with 90 per cent of the expenses covered by a grant. Local residents are expected to pay $1000 per house for the upgrade which will bring their properties up to health and safety regulations.

Ngatangiia member of parliament Ata Herman, speaking after the meeting, described the project as an investment.

“People are getting a $10,000 upgrade for only $1000,” he said.

Despite the cost the audience was overwhelmingly in favour of the proposal.

Muri Environment Caregroup chairwoman Mii Kauvai said the receptive response from the audience was due to the work WATSAN and the Muri Environment Caregroup had been doing together.

“Muri people are really concerned about water quality. Our children swim in it, people still eat fish here. If we don’t start cleaning it up, it’s never going to get better.”

The next steps for the programme include consulting with individual households as to the best payment options. People can pay either with a lump sum or pay $50 a month as part of their power bill. In the case of genuine hardship other funding was available.

Work is due to start in May and is planned to be completed by June 2013. It is expected that much of the work will be carried out by local contractors.

McDonald told CINews that any contractor wishing to tender for the work needed to be registered with the Cook Islands’ government.

“We have three drain laying companies on Rarotonga and another on Aitutaki. We are putting out international tenders and hope that we will get some international input but we want the majority of the work to be carried out by locals.”

After completing the domestic upgrades, the programme will change its focus to commercial properties and animal waste management.

Muri resident Karen Johnston summed up the feeling of the group “I’m looking forward to something happening.”

• Peter Campbell

Te Ipukarea Society (TIS) is concerned that the Cook Islands lacks legislation to protect sharks from being hooked by foreign fishing vessels in its waters.

Responding to a recent Radio New Zealand item about Marshall Islands police enforcing their newly-instituted shark fishing ban, TIS is pushing government to institute a similar ban – and in particular a ban on wire-trace.

Wire trace is a wire that attaches a hook to the nylon longline. When wire trace is involved, sharks are unable to break free from a hook and consequently die.

Studies show that nylon monofilament leaders are a viable alternative, as they reduce unwanted catch (including sharks) and increase targeted catch (in this case, tuna).

“If fishing vessels use wire trace on their longlines, they’re effectively targeting sharks,” the TIS executive’s statement reads.

“If there was a ban on wire trace, this would greatly reduce incidental catch of sharks. MMR (Ministry of Marine Resources) should be implementing their National Plan of Action on Sharks, which requires that fishing boats do not use wire trace.”

MMR secretary Ben Ponia says that MMR regulations are consistent with those of the Western and Central Pacific Fisheries Commission.

“MMR regulations require that shark carcasses are retained so as to discourage finning and the ratio of fin to carcass does not exceed five percent weight,” Ponia said. “This is consistent with the Conservation and Management Measures of the Western Central Pacific Fisheries Commission.”

But TIS says the Western Central Pacific Fisheries Commission (WCPFC) regulations represent “the only compromise agreement that parties of the WCPFC have been able to reach”, and urges the Cook Islands lawmakers to go a step further.

“It would be easy for the crew to hide a few bags of dried shark fins on a large fishing boat, and dump all the carcasses overboard. The incentive for crew to do this is very high, as shark fin is very valuable, and often the crew get to keep the proceeds of shark fin sales. And, without observers on the boat, we will have no way of monitoring what is happening,” TIS says.

The Radio New Zealand article which prompted TIS’ response notes that Marshall Islands authorities recently confiscated 60,000 pounds (about 27,200 kilogrammes) of shark carcasses and more than 1500 pounds (680 kilogrammes) of shark fins from a Japanese tuna vessel.

The offending vessel – the first to be apprehended since the Marshall Island banned all shark fishing at the end of last year – was fined US$125,000.

• Rachel Reeves

Representatives of all fishing associations under the umbrella of the Cook Islands Fishing Association (CIF) gathered for a two-hour annual general meeting on Tuesday afternoon.

In attendance were fishers, marine biologists and representatives of the Ministry of Marine Resources (MMR).

All members present elected this year’s executive – Don Beer replaces Mark Vaikai as president, Mark Baxter was voted vice president, Ina Kaikura treasurer, Willie John secretary, Fred Tereva the southern group representative, Ngatokorua Ngatokorua the northern group representative, Dick Marsters the Aitutaki and Pamati representative, and Steven Kavana and Wayne Barclay the Rarotonga representatives.

Among the items of discussion on the meeting agenda were foreign fishing licences, foreign vessels in the north, a shallow-water FAD at Avana, and the proposed shark sanctuary.

Pukapuka and Manihiki representatives raised concerns about foreign boats coming within close proximity of their local fishing boats, and one representative reported that often foreign boats come within 12 miles of small fishers. Those present agreed that longliners and foreign boats should be operating further offshore, and MMR representatives advised members to report incidences as soon as they occur.

While the proposed shark sanctuary and the marine park were discussed, the new executive has yet to formally state its stance on either.

Most members seemed to agree that the marine park will be good for the country, reports CIF project officer Vaine Wichman. However, the executive has yet to make a public statement.

The association discussed the prospect of a shallow-water FAD at Avana, for which ropes and materials are already available. An officer from the South Pacific Commission arrives this month to train fishers in FAD construction, deployment and maintenance.

Bonefish ambassador Jon Hall also made a presentation about the success of Aitutaki’s bonefishery and its guide licensing programme.

During the meeting CIF drafted its work plan for the coming year, which prioritises FADS and the sourcing of funding for safety gear.

The association also addressed specific issues like boats in Mauke which need repairing, a new freezer for Pamati, boat masters training for Aitutaki, fish processing and post-harvest support for Rakahanga fishers, lead lights at Avana and a proposal to install a freeze-blast machine in Rakahanga and an ice-making facility in Aitutaki.

It reviewed its outputs from last year, the most significant of which was the disbursement of over $100,000 in small grants to member clubs.

Each island benefited from the project funding – Aitutaki got lagoon and harbour lighting, Pamati got freezers for storage, Atiu got freight support, Mauke assistance with boat repair, Mitiaro fishing and safety gear, Rakahanga processing tables and fishing gear, Manihiki a cool store container, ice machine and fishing gear, Penrhyn fishing gear, Pukapuka fishing gear, Avana lead lights, Tutakimoa/Takuvaine fishing rods, Tupapa fishing rods and FAD materials and Avatiu safety radios.

• Rachel Reeves

PICI programme manager and Cook Islands Turtle Project expedition coordinator Jess Cramp with the projects two brand new cameras donated by CITC and Panasonic New Zealand. She is pictured here with CITC staff members Mere Short and Pokoroa Pauka. 12022810

Capturing turtles in their natural habitat and documenting the marine creatures will be an easier task for the Cook Islands Turtle Project team who this week were donated two Panasonic FT3 Lumix waterproof cameras by CITC and Panasonic New Zealand.

The Cook Islands Turtle Project, under the Pacific Islands Conservation Initiative umbrella, was recently awarded a Rufford Foundation grant for a sea turtle research expedition to Palmerston Atoll.

The research team is expected to make the voyage to Palmerton Atoll in April aboard the SV Southern Cross and the brand new cameras will be put to work documenting sea turtles.

Doctor Michael White, chief scientist of the Cook Islands Turtle Project and expedition leader, was delighted to hear of the donation.

“Sea turtles are difficult animals to study, apart from when on a nesting beach laying their eggs. These Panasonic cameras will allow us to photograph turtles underwater and use these images to confirm that we are seeing the same individual at a particular place. We look forward to providing many wonderful photos from our Palmerston expedition too,” says White.

“Meitaki maata to CITC and Panasonic New Zealand.”

CITC’s Loretta Siulepa says, “CITC, in association with Panasonic, is proud to supply two waterproof Panasonic cameras for the upcoming Cook Islands Sea Turtle Projects’ expedition to Palmerston. These cameras will be used to identify sea turtle tracks, individual turtles and for documentation of the expedition.”

Siulepa adds that the company’s slogan ‘bringing the best 2U in 2012’ is reflected in their support for this very worthwhile project.

“CITC began partnering with PICI last year with the rubbish roundup and will continue to be part of many other projects throughout 2012 and beyond.”

PICI and CITP are thankful for the support and are excited to begin the expedition.

If you have any questions regarding the expedition or additional space for passage to Palmerston, please contact PICI programme manager and expedition coordinator, Jess Cramp on jess@picionline.org or call her on 55955.

• Matariki Wilson