Cory's  Shearwater in flight

Joana Calado (Molecular and Environmental Biology Centre, University of Minho, Braga, Portugal) and colleagues have published in the journal Ocean & Coastal Management on Cory's Shearwaters Calonectris borealis (and other seabirds) that interact with Portuguese fishing vessels in the North-east Atlantic.

The paper’s abstract follows:

“Seabirds are marine predators known to forage in association with fisheries, however detailed knowledge on seabird-fishery interactions remains scarce in several regions of the world.  We quantified seabird-fishery interactions and bycatch in central Portuguese coastal waters (NE Atlantic) between 2016 and 2018 in four gears: purse-seines, longlines, gillnets, and fishing traps.  We mapped gear-specific fishing effort and seabird bycatch events and characterized fishery catches.  Specific objectives were to determine separately for seabird-fishery interactions and bycatch (i) the gear with the highest rates, (ii) the most abundant species, and (iii) to assess the main drivers (i.e. year, season, gear, and fishery catch) of seabird-fishery interactions.  Purse-seines had the highest seabird-fishery interactions, and the most abundant species were Yellow-legged and Lesser black-backed gulls, Northern gannet, and Cory's shearwater.  Total seabird-fishery interactions varied inter-annually but not seasonally, indicating high total seabird numbers at fishing boats year-round.  In contrast, higher fishery interactions were found during spring for Yellow-legged gulls. Age classes of individuals varied according to species, and fishery catches had a positive effect on seabird-fishery interactions.  Seabird bycatch occurred mostly in longlines and within the ‘Ilhas Berlengas’ Special Protection Area. Northern gannet and Cory's shearwater were the most bycaught species, and species ecological traits seemed important in determining gear-specific bycatch.  Our results suggest a strong influence of purse-seine and artisanal fisheries on seabirds in the NE Atlantic coast, and future studies should investigate the effects of these fisheries on seabird populations in other regions of the world”.

Reference:

Calado J.G., Ramos, J.A. Almeida, A.,  Oliveira, N., Paiva, V.H.  2020.  Seabird-fishery interactions and bycatch at multiple gears in the Atlantic Iberian coast.  Ocean & Coastal Management  doi.org/10.1016/j.ocecoaman.2020.105306.

John Cooper, ACAP Information Officer, 26 August 2020

Laysan Albatross V301, fledged 2016, seen back in 2020, photograph by Pacific Rim Conservation

V106 as a downy chick during hand rearing in 2015, photograph by Robby Kohley, Pacific Rim Conservation

VI06 back in the refuge, photograph by Megan Dalton, Pacific Rim Conservation

So far, four translocated Laysan Albatross Phoebastria immutabilis chicks have returned to the James Campbell National Wildlife Refuge on the Hawaiian island of Oahu, according to the environmental NGO, Pacific Rim Conservation.  The birds are V106, from the 2015 cohort (out of 10 fledglings) who first returned in 2018 and has been sighted each year since and V301, V309 and V315 from the 2016 cohort (from 19 fledglings) who returned for the first time this year.

The NGO writes “Each now-adult bird was spotted multiple times, and sometimes seen dancing together!  We couldn't be more excited about these birds returning to the predator exclusion fence and look forward to seeing more of them (and hopefully their offspring) in the near future!”

A total of 46 translocated Laysan Albatross chicks fledged from the James Campbell NWR over the three-year period 2015-2017.  Several hundred sightings of Laysans have been subsequently recorded within the refuge. A pair of wild adults has bred in the refuge for the first time, laying an egg in December 2017 (click here).

Translocated Black-footed Albatrosses P. nigripes are also being hand-reared in the James Campbell NWR, as are two other seabird species (click here).

Read more about the seabird translocation projects here.

Information from Pacific Rim Conservation’s Facebook page.

John Cooper, ACAP Information Officer, 25 August 2020

Black-browed Albatrosses gather behind a fishing vessel, photograph by Graham Robertson

Julien Collett and Henri Weimerskirch (Centre d'Etudes Biologiques de Chizé, Université de la Rochelle, Villiers-en-Bois, France) have published open access in the Proceedings of the Royal Society B Biological Sciences on the ability of Black-browed Albatrosses Thalassarche melanophris to memorize where they encountered vessels across consecutive foraging trips from Kerguelen.

The paper’s abstract follows:

“Human activities generate food attracting many animals worldwide, causing major conservation issues. The spatio-temporal predictability of anthropogenic resources could reduce search costs for animals and mediate their attractiveness. We investigated this through GPS tracking in breeding black-browed albatrosses attracted to fishing boats. We tested for answers to the following questions. (i) Can future boat locations be anticipated from cues available to birds? (ii) Are birds able to appropriately use these cues to increase encounters? (iii) How frequently do birds use these cues? Boats were spatially persistent: birds searching in the direction where they previously attended boats would encounter twice as many boats compared with following a random direction strategy. A large proportion of birds did not use this cue: across pairs of consecutive trips (n = 85), 51% of birds switched their foraging direction irrespective of previous boat encounters. Still, 15 birds (27%) were observed to closely approach (approx. 0.1–1 km) where they previously attended a boat while boats were no longer there. This is less than the distance expected by chance (approx. 10–100 km), based on permutation control procedures accounting for individual-specific spatial consistency, suggesting individuals could memorize where they encountered boats across consecutive trips. We conclude albatrosses were able to exploit predictive cues from recent boat encounters but most favoured alternative resources.”

Reference:

Collet, J. & Weimerskirch, H. 2020.  Albatrosses can memorize locations of predictable fishing boats but favour natural foraging.  Proceedings of the Royal Society B Biological Sciences 287.  doi.org/10.1098/rspb.2020.0958.

John Cooper, ACAP Information Officer, 24 August 2020

A Kilauea Point Laysan Albatross, lighthouse in the background, photograph by Jacqueline Olivera

The Kīlauea Point National Wildlife Refuge on the Hawaiian island of Kauai was established to preserve and enhance seabird breeding colonies, including the Laysan Albatross or Mōlī Phoebastria immutabilis (click here).  The Kīlauea Point NWR supported a total of 116 pairs of Laysan Albatrosses in the 2019/20 breeding season according to a Facebook post dated 17 April.  “Of those, 31 nests failed to hatch (broken, missing, etc.), 14 failed to hatch (but were incubated to full term), and 71 successfully hatched” (giving a hatching success of 61.2%).  “Of these 71, 19 chicks are missing or depredated (suspect feral cat [click here], feral pig, or owl) and 52 were alive and being fed by parents, although some chicks seemed very small and thin for their age”.

A downy Kilauea Point Laysan Albatross chick, photograph by Jacqueline Olivera

Following an enquiry at the time, the KNWR replied “the birds are protected by a fence that keeps out dogs and pigs.  Though, as you know, pigs are a persistent beast all their own and are still a concern which is why we actively conduct predator control for them if they breach our fence lines”.  A later report by USFWS Biologist Kim Uyehara, states “We … have an old fence, which feral pigs regularly breach and feral cats easily climb over.  We look forward to a new mammal-proof fence within the next few years”.  It is further reported that ground wortk fior the new fence will commence next year.

A Kilauea Point Laysan Albatross chick approaching fledging against the current pig-proof fence - that will not keep out feral cats, photograph by Louise Barnfield

The August 2020 edition of Wild Times, the newsletter of Friends of Kauaʻi Wildlife Refuges, reports “Laysan albatross (mōlī) fledging success rates at Kīlauea Point NWR this year are much lower than usual with only 36 chicks fledging out of 115 nests [within the fence*].  Low fledging success may be linked to decreased invasive species management capability as a result of staff shortages, reduced capabilities during the COVID-19 closure and challenges with extensive staff time needing to be devoted to avian botulism outbreaks at Hanalei NWR.”

However, an update received from Louise Barnfield, KPNWR volunteer who surveys the albatross colony, includes late fledging chicks to give a total of 44.  Overall breeding success for the 2019/20 season was thus 37.9% (with a fledging success of 44/71 or 62.0%). The chicks were not banded prior to fledging.  In the previous season (2018/19) 121 active nests were counted in December 2018.

*Note that one of the 116 nests in 2019/20 was just outside the existing fence.

With thanks to Louise Barnfield, KPNWR volunteer.

John Cooper, ACAP Information Officer, 21 August 2020, updated 02 September 2020