A Balearic Shearwater at sea

NOTE: This post continues an occasional series that features photographs of the 31 ACAP-listed species, along with information from and about their photographers.  Here, José Manuel ‘Pep’ Arcos (SEO BirdLife) writes about his efforts studying the Critically Endangered Balearic Shearwater Puffinus mauretanicus.

Pep Arcos holds a Balearic Shearwater in  Ibiza in 2014; photograph by David García

My interest in seabirds started well over 30 years ago.  First as a young birder, later as a researcher, and nowadays as a conservationist, although I like to believe that I keep these three approaches ingrained in me as one, and the Balearic Shearwater has been always there as a common thread.

A downy chick and an adult Balearic Shearwater at a marked study nest

The Balearic Shearwater is a threatened species endemic as a breeder to Spain’s Balearic Islands in the western Mediterranean.  With a global breeding population of about 3000 breeding pairs, it is experiencing a severe negative trend estimated at -14% per year, according to demographic modelling.  Adult survival is the weakest demographic parameter, and hence threats causing direct mortality are of main concern.  Current evidence points to fishing bycatch as the most acute threat, followed by predation by introduced mammals at breeding sites.

Balearic Shearwaters are excellent divers, able to reach a depth of 30 m

From my first days as a young birdwatcher in the second half of the 1980s, I recall the large congregations of these shearwaters in winter near Barcelona where I lived, usually reaching a few thousand birds.  At the time the Balearic Shearwater was considered a subspecies of the more abundant and widespread (and non-threatened) Manx Shearwater P. puffinus, and nobody paid much attention to these birds, but for me they were the closest thing to the mythical albatrosses in my “backyard”, and I was fascinated by them.  But most of my experience was limited to observations from the coast, and I wanted more.  So, after finishing my undergraduate degree in biology, I started my PhD focused on the use of fisheries discards by seabirds in the western Mediterranean.  This allowed me to get aboard fishing vessels regularly, and to enjoy close views of seabirds, with Balearic Shearwaters being among the most regular species observed.  During these years I enjoyed the life at sea in the company of fishers and became more and more interested in the ecology of this procellariiform.  The extensive use of discards by the species was remarkable compared to other shearwaters, and this implied a higher risk of bycatch, as fishers usually reported; although this was mainly related to longlines, a fishing modality with which I was not then familiar.

Seabirds, including Balearic Shearwaters, seek discards behind trawlers, one of the scenes I enjoyed photographing.  How much would I have enjoyed a digital camera in the late 1990s!

In the late 1990s and early 2000s, the Balearic Shearwater started to gain attention.  First, because it had been recognized as a distinct species, and one that is restricted to a very small breeding area, the Balearic Islands.  Second, because the Balearic Government, along with SEO/BirdLife (the Spanish BirdLife partner), conducted a EU-funded LIFE Project focused on the species, and started to gain knowledge of its conservation status.  During that time my work kept me focused on the sea, but I was lucky to collaborate with the LIFE project (it was called “LIFE Virot”, as “virot” is the local name for the species in Ibiza and Formentera, the southernmost Balearic Islands).  This collaboration allowed me to visit the breeding colonies for the first time in 2001, and I keep a strong memory of the first bird that I found face to face in a cave at night.  I was leaving when the bird landed in front of me on its way back from the sea.  It was after this project that SEO/BirdLife produced the first Spanish Red List Book in 2004, and I had the chance of writing the text for the Balearic Shearwater, along with my former PhD supervisor, Daniel Oro.  His expertise in demography, along with the data collected during the LIFE Virot project, allowed us to run the first Population Viability Analysis for the species. The results raised the alarm: an unusually low adult survival, most likely related with threats at sea, and a mean extinction time of 40 years.

In the last decade there has been increasing evidence of the threat that bycatch poses to Balearic Shearwaters, with several hundred reported killed by collaborative fishers, here including three Mediterranean Shags Phalacrocorax aristotelis desmarestii, six Scopoli’s Shearwaters Calonectris diomedea and one Balearic Shearwater

These raised concerns increased my interest in conservation biology and led me to apply for a position as a marine officer with SEO/BirdLife, where I started working in 2005 and started coordinating its marine programme shortly afterwards.  From this position, I’ve been able to keep working on applied research and conservation action, paying particular attention to the Balearic Shearwater.  Highlights include the elaboration of one of the first marine Important Bird Areas (mIBAs) inventories worldwide, which led to the designation of these sites as Marine Protected Areas by the Spanish Government in 2014; setting up a collaborative long-term breeding monitoring programme in Ibiza; revision of the international action plan of the species (2011); and ongoing collaborative work with fishers to understand and minimize bycatch.  All this work, often in collaboration with many other organizations, has provided novel information on the biology and the ecology of the species, as well as on its threats.

This is Quimera, the oldest known Balearic Shearwater, banded in 1986 as an “adult” in Mallorca.  I recaptured the bird in June 2021 with a hand net from a trawler off Barcelona, and deployed a GPS/GSM tracker that provided information for 45 days as it visited the colony and then left for the Atlantic, staying off Aveiro, Portugal.  We also added a plastic alpha-numeric band

During this time, SEO/BirdLife has also been active in policy work, promoting the recognition of the species by several international agreements, including ACAP, and becoming involved in its conservation through several activities at Spanish and European Union levels. However, despite all these improvements in knowledge and gains in recognition, there has been little progress in monitoring and conservation action on the ground by local authorities.  There are no official monitoring programmes in place, and severe threats such as bycatch and predation by introduced mammals have been not systematically addressed.  Meanwhile, the large congregations of shearwaters that attracted my attention 30 years ago are almost a memory from the past, and new demographic models strengthen the evidence of a severe population decline.  It’s time to move on, and to pass from theory to practice!

Selected references:

Abelló, P., Arcos, J.M. & Gil de Sola, L. 2003.  Geographical patterns of seabird attendance to a research trawler along the Iberian Mediterranean coast.  Scientia Marina  67 Suppl. 2: 69-75.

Afán, I., Arcos, J.M., Ramírez, F.,García, D., Rodríguez, B., Delord, K., Boué, A., Micol, T., Weimerskirch, H. & Louzao, M. 2021.  Where to head: environmental conditions shape foraging destinations in a critically endangered seabird.  Marine Biology  168:23.

Arcos, J.M. (compiler) 2011.  International species action plan for the Balearic shearwater, Puffinus mauretanicus.  SEO/BirdLife & BirdLife International.

Arcos, J.M. & Oro, D. 2002.  Significance of nocturnal purse seine fisheries for seabirds: a case study off the Ebro Delta (NW Mediterranean).  Marine Biology 141: 277-286.

Arcos, J.M. & Oro, D. 2002.  Significance of fisheries discards for a threatened Mediterranean seabird, the Balearic shearwater Puffinus mauretanicus.  Marine Ecology Progress Series  239: 209-220.

Arcos, J.M. & Oro, D. 2004. Balearic Shearwater, Puffinus mauretanicus (in Spanish, English summary).  In: Madroño, A., González, C. & Atienza, J.C. (Eds).  Libro Rojo de las Aves de España.  Madrid: Dirección General para la Biodiversidad & SEO/BirdLife.  pp. 46-50.

Arcos, J.M., Arroyo, G.M., Bécares, J., Mateos-Rodríguez, M., Rodríguez, B., Muñoz, Ruiz, A., de la Cruz, A., Cuenca, D., Onrubia, A. & Oro, D. 2012.  New estimates at sea suggest a larger global population of the Balearic Shearwater Puffinus mauretanicus.  In: Yésou, P., Bacceti, N. & Sultana, J. (Eds).  Ecology and Conservation of Mediterranean Seabirds and other Bird Species under the Barcelona Convention.  Proceedings of the 13th MEDMARAVIS Pan-Mediterranean Symposium, Alghero (Sardinia).  pp. 84-94.

Arcos J.M., Bécares J., Rodríguez B. & Ruiz A. 2009.  Áreas Importantes para la Conservación de las Aves marinas en España.  Madrid: Sociedad Española de Ornitología (SEO/BirdLife).

Arcos, J.M., Bécares, J., Villero, D., Brotons, L., Rodríguez, B. & Ruiz, A. 2012.  Assessing the location and stability of foraging hotspots for pelagic seabirds: an approach to identify marine Important Bird Areas (IBAs) in Spain.  Biological Conservation 156: 30-40.

Arcos, J.M., Louzao, M. & Oro, D. 2008.  Fishery ecosystem impacts and management in the Mediterranean: seabirds point of view.  In: Nielsen, J.L., Dods, J.J., Friedland, K., Hamon, T.R., Musick, J. & Verspoor, E. (Eds).  Reconciling Fisheries with Conservation: Proceedings of the Fourth World Fisheries Congress.  Bethesda: American Fisheries Society.  pp. 1471-1479.

Arcos, J.M., Massutí, E., Abelló, P. & Oro, D. 2000.  Fish associated with floating drifting objects as a feeding resource for Balearic Shearwaters Puffinus mauretanicus during the breeding season.  Ornis Fennica 77: 177-182.

Cortés, V., Arcos, J.M. & González-Solís, J. 2017.  Seabirds and demersal longliners in the northwestern Mediterranean: factors driving their interactions and bycatch rates.  Marine Ecology Progress Series ..565: 1-16.

Genovart, M., Arcos, J.M., Álvarez, D., McMinn, M., Meier, R., Wynn, R., Guilford, T. & Oro, D. 2016.  Demography of the critically endangered Balearic shearwater: the impact of ries and time to extinction.  Journal of Applied Ecology  53: 1158-1168.

Laneri, K.F., Louzao, M., Martínez-Abraín, A., Arcos, J.M., Belda, E., Guallart, J., Sánchez, A., Giménez, M., Maestre, R. & Oro, D. 2010.  Trawling regime influences longline seabird bycatch in the editerranean: new insights from a small-scale fishery.  Marine Ecology Progress Series  20: 241-252.

Louzao, M., Hyrenbach, D., Arcos, J.M., Abelló, P., Gil de Sola, L. & Oro, D. 2006.  Oceanographic habitat of a critically endangered Mediterranean procellariiform: implications for the design of Marine Protected Areas.  Ecological Applications  16: 1683-695.

Louzao, M. Arcos, J.M., Guijarro, B., Valls, M. & Oro, D. 2011.  Seabird-trawling onteractions: factors affecting species-specific to regional community utilisation of fisheries waste.  Fisheries Oceanography  20: 263-277.

Louzao, M., Delord, K. García, D., Afán, I., Arcos, J.M. & Weimerskirch, H. 2021.  First days at sea: depicting migration patterns of juvenile seabirds in highly impacted seascapes.  Peer J 9: e11054.

Meier, R.E., Wynn, .B., Votier, S.C., McMinn Grivé, M., Rodríguez, A., Maurice, L., van Loon, E.E., Jones, .R., Suberg, L., Arcos, J.M., Morgan, G., Josey, S. & Guilford, T. 2015.  Consistent foraging areas and commuting corridors of the critically endangered Balearic shearwater Puffinus mauretanicus in the northwestern Mediterranean.  Biological Conservation  190: 7-97.

Navarro, J., Louzao, M., Igual, J.M., Oro, D., Delgado, A., Arcos, J.M., Genovart, M., Hobson, K.A. & Forero, M.G. 2009.  Seasonal changes in the diet of a critically endangered seabird and the importance of trawling discards.  Marine Biology  156: 2571-578.

Pérez-Roda, A., Delord, K., Boué, A., Arcos, J. M., García, D., Micol, T., Weimerskirch, H., Pinaud, D. & Louzao, M. 2017.  Identifying mportant Atlantic areas for the conservation of Balearic shearwaters: spatial overlap with onservation areas.  Deep-Sea Research Part II  141: 285-293.

Ruiz, A. & Martí, R. (Eds.). 2004.  La Pardela Balear.  Madrid: SEO & BirdLife-Conselleria de Medi Ambient del Govern de les illes Balears.

Pep Arcos, Marine Officer, SEO/BirdLife, Spain, 02 February 2022

Black-browed Albatrosses gather behind a trawler in the South Atlantic; photograph by Graham Parker

Amanda Kuepfer (South Atlantic Environmental Research Institute) and colleagues have published in the journal Biological Conservation on batch discarding of trawler offal as a mitigation measure to reduce seabird mortality.

The paper’s abstract follows:

“Incidental mortality in trawl fisheries is a serious threat to seabird sustainability.  Driven primarily by seabirds attracted to discards, limiting discard discharge through strategic batching is a best practice mitigation measure recommended by the Agreement on the Conservation of Albatrosses and Petrels (ACAP).  However, studies supporting the efficacy of batch discarding are rare, limited to the south-western Pacific, and assess seabird numbers attending vessels only, not gear contact rates.  The effectiveness of batch discarding in areas with different seabird communities, fishery assemblages, and natural prey availability is therefore unknown.  Here we quantify both seabird numbers and gear contact rates in response to strategic discard discharge in the Falkland Islands trawl fleet for two high-risk species groups: black-browed albatross (Thalassarche melanophris) and giant petrel species (Macronectes spp.).  Specifically, we test the effect of three different discharge treatments (zero, batch and continuous discarding) at two vessels.   Bird abundance and contact rates were positively related, but zero discarding consistently reduced seabird numbers attending trawlers and eliminated contacts with warp cables and tori-lines. Batching significantly reduced bird abundance and contact rates at the vessel that stored all discards between batches.  At the other vessel, however, intermittent release of hashed viscera diminished the mitigation effect.  Our findings validate the generality of batch discarding as an effective mitigation measure in trawl fisheries where zero discarding is not possible, whilst highlighting the importance of complete waste storage.”

A Black-browed Albatrosses collides with a trawler warp in the South Atlantic; photograph by Graham Parker

Reference:

Kuepfer, A., Sherley, R.B., Brickle, P., Arkhipkin, A. & Votier, S.C. 2022.  Strategic discarding reduces seabird numbers and contact rates with trawl fishery gears in the Southwest Atlantic.  Biological Conservation  266.  doi.org/10.1016/j.biocon.2022.109462.

John Cooper, ACAP Information Officer, 01 February 2022

The Black-footed Albatross was the first new species I saw when I started my life-long love of the wildlife of the Northwestern Hawaiian Islands

NOTE:  This post continues an occasional series that features photographs of the 31 ACAP listed species, along with information from and about their photographers.  Here Beth Flint  of the US Fish and Wildlife Service writes of the Near Threatened Black-footed Albatrosses Phoebastria nigripes she has known and subsequently worked with since her days as a student.

Beth Flint with a plastic decoy Short-tailed Albatross that was willing to pose with her in the off-season

My first encounter with a Black-footed Albatross came as I first stepped of the plane at Tern Island, French Frigate Shoals in January of 1980.  I was there to do fieldwork on Sooty Terns Onychoprion fuscatus and with the typical single-mindedness of a young graduate student had not even thought about the fact that I would be living in a breeding colony of magnificent Black-footed Albatrosses.  I was immediately smitten with these regal, aloof birds, sometimes stoic and sometimes exuberant.  I had fallen in love with colonial seabirds from reading about them during my studies in wildlife biology at the University of Montana and went on to study with Nicholas Collias, the ethologist at the University of California, Los Angeles (UCLA), without ever having set foot in a seabird colony.

Enthralled with their new egg, Laysan Island 26 November 2004; photograph by Mark MacDonald

My study site was located in one of the earliest major conservation areas protected in the United States.  Human exploitation of seabirds (particularly Laysan P. immutabilis and Black-footed Albatrosses) on the breeding grounds in the forms of guano mining, egg collection for albumin used in photography, and then feather hunting for stuffing mattresses started afflicting the populations of these birds in the Northwestern Hawaiian Islands in 1891.  In 1903 Teddy Roosevelt, moved by public outcry about the destruction caused by the feather hunters coming from Japan, placed the islands under Navy protection stationed at Midway Atoll and in 1909 declared the entire northern end of the archipelago from Nihoa 1200 miles [1930 km] north to Kure as the Hawaiian Islands Bird Reservation.

Through the years, the name, the boundaries, and the mission have changed and today this area is known as the Papahānaumokuākea Marine National Monument. This enormous no-take Marine Protected Area protects the islands and waters out to the 200-mile [320-km] Exclusive Economic Zone boundary and is 583 000 square miles [1.5 million square km] in area.  It is managed by a Board containing the United States Fish and Wildlife Service, National Oceanic and Atmospheric Administration, State of Hawaii, and the Office of Hawaiian Affairs.  I work for the Department of Interior in the U.S. Fish and Wildlife Service as a wildlife biologist and am responsible for advising the Refuge Managers on technical issues that will help them make management decisions and monitoring populations and habitats in the Marine National Monuments of the central tropical Pacific.

Midway Atoll in 2015

Although these islands are remote and most can only be reached by ship, they are much less rugged than are the breeding homes of many other species in this photo essay series.  A fair amount of research has been undertaken on the breeding biology, movement ecology, effects of contaminants, demography and survival rates of the Black-footed Albatross.  Tens of thousands [have been banded by refuge staff since the middle of the last century.  Citizen scientists have made a huge contribution to monitoring population size by undertaking a complete census of all the albatrosses at Midway Atoll each year since 1992.

Over a century of land and sea-based protection has enabled these populations to recover from the insults of the beginning of the 20th century and current populations are stable.  As with the majority of seabird species, the dominant population level threats for Laysan and Black-footed Albatrosses are introduced predators in the breeding colonies and fisheries interactions.  For almost 30 years the Fish and Wildlife Service and their partners have been tracking the effects of commercial fishing on Black-footed Albatross survival rates and working with colleagues to minimize the negative interactions between this species and fishing gear.  While other more localized problems also exist, it has become increasingly clear that the threat that will eclipse all others for Black-footed Albatrosses is climate change.

Six of the sixteen Black-footed Albatross breeding islands in the world accommodate more than 95% percent of global population of less than 70 000 pairs and are lower in elevation than 25 metres above sea level.  These low islands are already showing periodic inundation due to storms of increased frequency and intensity and accelerating erosion and loss of entire islets.  At French Frigate Shoals three of 10 islets have already washed away completely during storms, rendering thousands of pairs of Black-footed Albatross homeless.  Adults and chicks in the colonies are also exhibiting increased levels of thermal stress and dying in greater numbers from heat injury and the birds face disruptions in prey availability due to hot water events and ocean acidification.

Black-footed Albatross colony (with Latsan Albatrosses and Masked Boobies) on Whaleskate Island at French Frigate Shoals in the spring of 1980.  The entire island was washed away in the 1990s

 
A Black-footed Albatross chick works hard to stay cool with Sooty Tern chicks taking advantage of its shade.  Northern hemisphere albatrosses (Black-footed, Laysan and Short-tailed P. albatrus) are winter breeders, possibly as a phylogenetic holdover from their relatives in the southern hemisphere or perhaps because they breed in the subtropics and tropics so cannot manage ambient temperatures in the summer months at their breeding sites.  Increasingly, there is high mortality when the adults return to the colony during the hot, windless days of early autumn or in the late spring when chicks die by the thousands

Colonial seabirds have had difficulty withstanding the many ecological insults caused by the rampant success of Homo sapiens.  Albatross-like seabirds have moved across the face of the earth for upwards of 60 million years.  They have persisted during sea levels more than 100 metres higher than today.  In some ways these birds possess characteristics that might make us predict they will be better equipped to survive the coming climate troubles than many more sedentary species.  They possess extraordinary mobility and forage over the entire North Pacific Ocean.  They will likely be able to adjust to changed conditions on their foraging grounds.  However, safe breeding sites for birds that cannot withstand mammalian predators have become rare during the age of man.  For Black-footed Albatrosses to persist into the future we may need to restore high islands at latitudes with appropriate thermal conditions by ridding them of rodents, ungulates and carnivores and resort to assisted colonization to help this species through the troubled times to come.

Erosion at Midway Atoll has eliminated hundreds of albatross nests.  Black-footed Albatrosses tend to nest closer to the sea than do Laysan Albatrosses, so were likely affected disproportionately

A partnership involving U.S. Government Departments and NGOs such as Pacific Rim Conservation is implementing an innovaticonservation effort to establish new breeding colonies for seabirds affected by sea level rise and increased storm intensity.  A total of 511 chicks of four species (Laysan Albatross, Black-footed Albatross, Bonin Petrel Pterodroma hypoleuca and Tristram’s Storm Petrel Hydrobates tristrami) has been translocated to a predator-proof fenced area at the James Campbell National Wildlife Refuge on Oahu, primarily from low islands in the Papahānaumokuākea Marine National Monument, over the last six years.  Of those, 471 (92%) have fledged and adult birds of all four species have returned to the site.  Translocated Bonin Petrels have already started breeding and successfully fledging chicks from the refuge.  This conservation effort provides a climate-resilient nesting habitat for species threatened by sea level rise in the low-lying areas of the Monument.  Motivated by the same reasons as described above, USFWS and Pacific Rim Conservation, together with Mexico’s Comisión Nacional de Áreas Naturales Protegidas (CONANP) and the Mexican environmental NGO Grupo de Ecología y Conservación de Islas (GECI) collaborated to reintroduce Black-footed Albatrosses from the USA’s Midway Atoll National Refuge to Guadalupe Island Biosphere Reserve, Mexico.  In early 2021, they transferred 21 eggs and nine chicks to Guadalupe and the 27 surviving chicks were expected to fledge in June.  More birds will be moved in 2022 and 2023.

My hope is that this chick preparing to fledge from Laysan Island will be able to live out its long life on its natal island but that its cousins survive on new high island sites to carry on the Black-footed Albatross way of life

Selected Publications:

Batten, S.D., Chen, X., Flint, E.N., Freeland, H.J., Holmes, J., Howell, E., Ichii, T., Kaeriyama, M., Landry, M.R., Lunsford, C., Mackas, D.L., Mate, B., Matsuda, K., McKinnell, S.M., Miller, L., Morgan, K.H., Pen, A., Polovina, J.J., Robert, M., Seki, M.P., Sydeman, W.J., Thompson, S.A., Whitney, F.A., Woodworth, P. & Yamaguchi, A. 2010.  Status and trends of the North Pacific oceanic region 2003-2008.  In: McKinnell, S.M. & Dagg, M.J. (Eds).  Marine Ecosystems of the North Pacific Ocean, 2003-2008.  PICES Special Publication 4.

Brooke, M.de L., Bonnaud, E., Dilley, B.J., Flint, E.N., Holmes, N.D., Jones, H.P., Provost, P., Rocamora, G., Ryan, P.G., Surman, C. & Buxton, R.T. 2018.  Enhancing the value of future island eradications need improved understanding of past outcomes.  Animal Conservation 21: 19-20.

Dearborn, D.C., Anders, A.D. & Flint, E.N. 2001.  Trends in reproductive success of Hawaiian seabirds: is guild membership a good criterion for choosing indicator species?  Biological Conservation 101: 97-103.

Doherty, P.F. Jr., Kendall, W.L., Sillett, S., Gustafson, M., Flint, B. [E.N.], Naughton, M., Robbins, C.S. & Pyle, P. 2006.  Development of a banding database for north Pacific albatross: implications for future data collection.  Atoll Research Bulletin 543: 173-179.

Duhr, M., Flint, E.N., Hunter, S.A., Taylor, R.V., Flanders, B., Howald, G. & Norwood, N. 2019.  Control of house mice preying on adult albatrosses at Midway Atoll National Wildlife Refuge.  In: Veitch, C.R., Clout, M.N., Martin, A.R., Russell J.C. & West, C.J. (Eds).  Island Invasives: Scaling up to Meet the Challenge.  Occasional Paper SSC No. 62.  Gland: IUCN.  pp. 21-25.

Flint, E.N. 1997.  Interactions between albatrosses and pelagic longline fisheries in the North Central Pacific.  ‘Elepaio  57: 119-121.

Flint, E.N. 1999.  Status of seabird populations and conservation in the tropical island Pacific.  In: Eldredge, L., Maragos, J., Holthus, P. & Takeuchi, H.F. (Eds).  Marine and Coastal Biodiversity in the Tropical Island Pacific Region: Population, Development, and Conservation Priorities.  Vol. 2.  Honolulu: East-West Center.

Flint, E.N. 2011.  Midway Atoll.  In: Gillespie, R. & Clegg, D.A. (Eds).  Encyclopedia of Islands.  Berkeley: University of California Press.  pp. 631-633.

Flint, E.N. & Fraiola, K. 2021.  Status and trends of albatrosses in the Northwestern Hawaiian Islands.  In: Hyrenbach, K.D., Ishizaki, A., Polovina, J. & Ellgen, S. (Eds).  The Factors influencing Albatross Interactions in the Hawaii Longline Fishery: Towards Identifying Drivers and Quantifying Impacts. U.S. Dept. of Commerce, NOAA Technical Memorandum NOAA-TM-NMFS-PIFSC 122.  163 pp.

Gutowsky, S.E., Tremblay, Y., Kappes, M.A., Flint, E.N., Klavitter, J., Laniawe, L., Costa, D.P., Naughton, M.B., Romano, M.D. & Shaffer, S.A. 2014.  Divergent post-breeding distribution and habitat associations of fledgling and adult Black-footed Albatrosses Phoebastria nigripes in the North Pacific.  Ibis 156: 60-72.

Kendall, B., Flint, E., Naughton, M., Swift, R., Romano, N., Peterjohn, B. & Pearson, K. 2021.  Survival and breeding probability of Black-Footed and Laysan Albatrosses at Midway Atoll and Laysan Island, 2006-2015.  In: Hyrenbach, K.D., Ishizaki, A., Polovina J. & Ellgen S. (Eds).  The Factors influencing Albatross Interactions in the Hawaii Longline Fishery: Towards Identifying Drivers and Quantifying Impacts.  U.S. Dept. of Commerce, NOAA Technical Memorandum NOAA-TM-NMFS-PIFSC 122.  163 pp.

Polovina, J., Mitchum, G., Graham, N., Craig, M., DeMartini, E. & Flint, E. 1994.  Physical and biological consequences of a climate event in the central North Pacific.  Fisheries Oceanography 3: 15-21.

Reynolds, M.H., Courtot, K.N., Berkowitz, P., Storlazzi., C.D., Moore, J. & Flint, E. 2015.  Will the effects of sea-level rise create ecological traps for Pacific island seabirds?  PLoS ONE  10(9): e0136773.

Véran, S., Gimenez, O., Flint, E., Kendall, W.L., Doherty, P.F. Jr. & Lebreton, J. 2007.  Quantifying the impact of longline fisheries on adult survival in the Black-footed Albatross.  Journal of Applied Ecology  44: 942-952.

Beth Flint, Marine National Monuments of the Pacific, US Fish and Wildlife Service, Honolulu, Hawaii, USA, 31 January 2022

 
A Cory's Shearwater grounded by artificial lighting; photograph by Beneharo Rodriguez

Airam Rodríguez (Canary Islands’ Ornithology and Natural History Group, Buenavista del Norte & Department of Ecology, Universidad Autónoma de Madrid, Spain) and colleagues have published open access in the journal Frontiers in Ecology and Evolution on factors affecting grounding of Cory’s Shearwaters Calonectris borealis fledglings due to light pollution

The paper’s abstract follows:.

“Light pollution causes attraction and/or disorientation of seabirds, leading to mortality events due to multiple threats.  This is a poorly understood phenomenon, largely because of the challenge to track seabirds at night from their nests to the grounding light-polluted locations.  New tracking technologies can inform about this phenomenon.  Here, we used GPS transmitters with remote download to track the flights of Cory’s shearwater Calonectris borealis fledglings from an inland experimental releasing site to the ocean.  We released birds assigned to three experimental groups: GPS tagged, tape-labelled, and control birds.  We assessed how both intrinsic (such as body mass, body condition, body size, and down abundance) and extrinsic (i.e., flight descriptors, such as distance, straightness, and flight duration, wind speed, or moon luminance) factors influenced light-induced groundings by using two datasets: one including the three groups and another including just the GPS tagged birds (as GPS devices provide unique information).  We tested whether the probability of being grounded by artificial lights was related to intrinsic factors.  With the use of the whole dataset, we found that birds with a higher down abundance had a higher probability of being grounded.  GPS data revealed that the probability of being grounded was positively related to the tortuosity of flights and the overflown light pollution levels.  Also, birds with slower flights were more likely to be grounded than birds with fast flights.  Tortuosity increased with light pollution levels but decreased with the ambient light of the moon.  GPSs with remote data download provided information on birds reaching the ocean, this being a substantial improvement to previous studies requiring recapture of the individuals to retrieve the data.  GPS tracks of birds reaching the ocean allowed us to know that some birds overflew coastal urban areas so light-polluted as the landing sites of grounded birds.  We provide novel scientific-based information to manage seabird mortality induced by artificial lights.”

Movement trajectories of ten Cory’s Shearwater fledglings tracked with GPS-GSM devices. Ring refers to the unique ring codes of the birds. The animation shows the irradiance values (nW/cm2/sr), as a proxy of light pollution (bluish), taken from a cloud-free composite of VIIRS nighttime lights corresponding to November 2019

With thanks to Airam Rodríguez Martín.

Reference:

Rodríguez, A., Rodríguez, B., Acosta, Y. & Negro, J.J. 2022.  Tracking flights to investigate seabird mortality induced by artificial lights.  Frontiers in Ecology and Evolution.  doi.org/10.3389/fevo.2021.786557.

John Cooper, ACAP Information Officer, 28 January 2022