George and Geraldine (left) will not rear a chick in 2022; photograph by Jon Plissner, 20 January 2022

ACAP Latest News has been following the fortunes of George and Geraldine, the Vulnerable Short-tailed Albatross Phoebastria albatrus pair on the USA’s Midway Atoll for several years (click here).  To date they have successfully fledged three chicks since first meeting up in 2016, laying their most recent egg in October last year.  However, there will be no chick leaving the island this year as reported on the Friends of Midway Atoll National Wildlife Refuge Facebook page.

“The current short-tailed albatross pair on Midway have successfully raised chicks for the past several years, always in the same location south of the runway on Sand Island.  This year their routine was progressing as expected while scientists monitored the nest from a distance and with a remote camera, all while waiting for the egg to hatch when it normally does around January 1st.  Though the actual hatching is generally not observed, the behavior of the attending parent clearly changes when there is a squirming chick under them instead of the egg. This year, it was noticed that a parent was still sitting firmly on the nest well after the 1st, which was not a good sign.

By January 8th, both parents were attending to the nest together, the female "Geraldine" on the nest with her mate "George" sitting alongside. Scientists were unable to get a view inside of the nest to discern the egg's status.  With every passing day, it was less and less likely that the egg was viable.

This picture was taken by Fish and Wildlife Service Biologist Jon Plissner on January 20th, a first view to confirm that the egg had indeed failed. There are no guesses as to what might have happened.

Short-tailed albatross are endangered and were once even thought to be extinct.  These two on Midway Atoll National Wildlife Refuge are currently the only breeding pair outside of Japan and will hopefully return to have a successful egg again next year.”

John Cooper, ACAP Information Officer, 04 February 2022

One of two Short-tailed Albatross chicks on Mukojima in January 2022; photograph from the Yamashina Institute for Ornithology

Two Vulnerable Short-tailed Albatross Phoebastria albatrus chicks hatched on Mukojima in the Ogasawara Islands last month.  The locality is the site where 69 chicks were translocated from Torishima and hand-reared over five seasons by the Yamashina Institute for Ornithology (click here).

“This is the first time that two chicks have hatched in one breeding season in Mukojima Island since the start of our project.  In addition, there is another piece of good news.  One of these The Ichicks is the first chick that belongs to the 3rd generation starting from the 69 Short-tailed Albatrosses translocated to this island from Torishima Island and fledged there.  We are nstiucelebrating the birth of a chick that is the first grandchild [sic] of the translocated birds.  This shows that the project has made another step forward towards the goal of establishing a self-sustained breeding population in Ogasawara Islands.” (from the Institute's Facebook page).

John Cooper, ACAP Information Officer, 03 February 2022

 
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