The12th Meeting of the Working Party on Ecosystems and Bycatch (WPEB12) of the Indian Ocean Tuna Commission (IOTC) was held in Victoria, Mahé, Seychelles from 12-16 September.

The Albatross and Petrel Agreement was represented by Anton Wolfaardt, Convenor of its Seabird Bycatch Working Group.  The meeting considered a number of seabird-related papers, two of which were submitted by ACAP.  One of these papers (IOTC-2016-WPEB12-34, ACAP advice for reducing the impact of pelagic longline fishing operations on seabirds) by Anton Wolfaardt, Marco Favero and Nathan Walker summarised the latest ACAP best-practice advice for reducing seabird bycatch associated with pelagic longline fisheries.  ACAP’s advice was updated most recently at the Ninth Meeting of its Advisory Committee (AC9) in May 2016 to modify the recommended line-weighting specifications, and to include in the list of best-practice mitigation measures two hook-shielding devices.  These two devices encase the point and barb of baited hooks until a prescribed depth or immersion time has been reached, thus reducing the likelihood of seabirds becoming hooked.

The WPEB supported both aspects of the updated ACAP best-practice advice, and recommended that when the IOTC Seabird Conservation and Management Measure (Resolution 12/06 On reducing the incidental bycatch of seabirds in longline fisheries) is next reviewed, the line-weighting specifications be updated to conform with the latest ACAP advice.  It further recommended that the two hook-shielding devices recommended by ACAP be incorporated as additional mitigation options.  This recommendation by the WPEB will be further discussed and considered by the IOTC Scientific Committee, at its 19th Meeting to be held from 1-5 December this year in the Seychelles.

Click here to access the official report of WPEB12

Anton Wolfaardt, Convenor, ACAP Seabird Bycatch Working Group, 11 October 2016

Steffen Oppel (Royal Society for the Protection of Birds, Sandy, U.K.) and colleagues have a paper accepted by Emu Austral Ornithology that reports on the breeding success of island-endemic and Endangered Henderson Petrels Pterodroma atrata in the face of predation by introduced Pacific or Polynesian Rats Rattus exulans 

The manuscript’s abstract follows:

“One of the most important breeding colonies for gadfly petrels in the sub-tropics, Henderson Island in the South Pacific Ocean, was subjected to a rat eradication attempt in 2011, but the eradication failed.  Here we examine whether the current population status of the endemic Henderson Petrel Pterodroma atrata is consistent with an ongoing population decline.  We collected basic biological information on Henderson Petrels in 2015 to compare estimates of breeding population size and nest survival to data from 1991.  We found that the extrapolated population size of 19,987 pairs was marginally higher than the comparable estimate of 18,668 in 1991.  We also estimated the nest survival of 25 nests to be 28.5%, and most nest failures occurred within 7 days of hatching when chicks were killed by rats (n = 3) or a crab (n = 1).  Breeding success was higher than in 1991, and possibly sufficient for a stable population.  Although differences in survey effort render it difficult to directly compare estimates from 1991 and 2015, there is currently no evidence that the conservation status of the Henderson Petrel has deteriorated since it was listed as 'Endangered' by the IUCN.”

Henderson Petrel, photograph by Mike de L. Brooke

Read more here.

Reference:

Oppel, S., Lavers, J., Donaldson, A., Forrest, A., McClelland, G., Bond, A. & Brooke, M. Accepted ms.  Population status, breeding success and ecology of the Henderson Petrel after a failed rat eradication on Henderson Island.  Emu.

John Cooper, ACAP Information Officer, 07 October 2016

A commercial fishing boat skipper who caused the death of 39 threatened albatrosses refused to use a bird-scaring line, a court has been told.

The vessel’s master was fishing for Southern Bluefin Tuna Thunnus maccoyii off the West Coast of New Zealand in April this year and failed to use a bird-scaring line during two fishing trips, a mandatory requirement for the fishery, resulting in the capture of 41 albatrosses, 39 of which died.  A Ministry for Primary Industries (MPI) observer on board noticed that 10 longlines with up to 1400 hooks were set without a bird-scaring line, despite one being aboard and the captain being informed he was required to deploy it.

The albatrosses killed were 24 Buller’s Thalassarche bulleri, 14 White-capped T. steadi and one Wandering Diomedea exulans.  Single southern Royal D. epomophora and White-capped Albatrosses were released alive. According to information to hand the Buller’s Albatrosses would have been of the southern nominate race that were feeding chicks at the time, which will not have survived to fledging with only one parent remaining to feed them.

Buller's Albatross, photograph by Chris Golding

The court was told the captain knew he had to use a bird-scaring line under the Fisheries (Commercial Fishing) Regulations and had admitted to not using one.  The captain pleaded guilty but stated that “he did not use streamer lines because he was concerned for the safety of his crew and they cost him time and money when the streamer lines damaged the fishing vessel".

Sentencing is set for 14 November.  The maximum fine for the offence is NZ$ 100 000 and forfeiture of the fishing vessel.

The MPI is now considering the mandatory use of weighted lines for pelagic longliners.

Read more:

http://www.stuff.co.nz/national/crime/84933279/fisherman-pleads-guilty-to-38-albatross-deaths

http://www.newshub.co.nz/nznews/west-coast-fisherman-admits-causing-deaths-of-38-albatross-2016100412

http://www.stuff.co.nz/national/82116704/Commercial-fisherman-prosecuted-over-38-albatross-deaths-on-West-Coast

http://www.nzherald.co.nz/nz/news/article.cfm?c_id=1&objectid=11722328

https://www.tvnz.co.nz/one-news/new-zealand/fisherman-pleads-guilty-killing-39-albatrosses

John Cooper, ACAP Information Officer, 06 October 2016

Graham Robertson (Kingston, Tasmania, Australia) and colleagues have published in the journal Polar Biology on population increases of Black-browed Thalassarche melanophris and Grey-headed T. chrysostoma Albatrosses on Chilean islands.

Black-browed Albatross

Grey-headed Albatross, photographs by Cristián Suazo

The paper’s abstract follows:

“Black-browed albatrosses (Thalassarche melanophris) are killed incidentally in commercial fishing operations.  Aerial surveys in 2002 and 2011 revealed the number of black-browed albatrosses at the Diego Ramírez and Ildefonso islands, Chile, increased by 52 and 18 %, respectively.  The increases were attributed to reduced mortality in the longline fishery for Patagonian toothfish (Dissostichus eleginoides) following fleet conversion to a new gear configuration with much higher average hook sink rates.  A new survey in 2014 revealed the number of black-browed albatrosses at Ildefonso was about the same as in 2011, but the number at Diego Ramírez had increased by a further 29 % (8.8 %/year).  The number of greyheaded albatrosses (Thalassarche chrysostoma) at Diego Ramírez also increased, by 23 %, in the same time period.  In 2014, Ildefonso held an estimated 54,284 breeding pairs of black-browed albatrosses.  The populations of blackbrowed albatrosses at two more northern sites, the Evangelistas and Leonard islets, stood at 4818 and 545 breeding pairs, respectively.  The total number of breeding pairs of both albatross species at Diego could not be determined because not all islands in the archipelago were surveyed.”

Black-browed Albatrosses hunker down on their nests in strong wind on a Chilean Island, photograph by Graham Robertson

With thanks to Cristián Suazo.

Reference:

Robertson, G., Wienecke, B., Suazo, C.G., Lawton, K., Arata, J.A. & Moreno, C. 2016.  Continued increase in the number of black-browed albatrosses (Thalassarche melanophris) at Diego Ramírez, Chile.  Polar Biology DOI 10.1007/s00300-016-2028-5.

John Cooper, ACAP Information Officer, 05 October 2016