Rocas Alijos (Alijos Rocks) are located 320 km west of Baja California, Mexico. They consist of three volcanic rocky spires: North (29 m high), Middle (18 m) and South (35 m) Rocks along with numerous smaller low-lying rocks that are often awash.

Rocas Alijos

 South Rock, North Rock and Middle Rock from left to right

Laysan Albatrosses regularly roost and are presumed to breed on both South and North Rocks

The total exposed surface area on the two rocks (North and South) where Laysan Albatrosses Phoebastria immutabilis are thought to breed is only a hundred square metres or so.  There is a small amount of loose soil on top of South Rock, but no terrestrial plants or breeding land birds have been observed.  South and Middle Rocks were climbed for the first time in 1990; it appears that a landing has not been made on North Rock.

South Rock is severely undermined with daylight visible through the base at all angles.  Three Laysan Albatrosses are just visible at its top

Laysan Albatrosses were first recorded at Rocas Alijos in February 1976 when 10 were present; birds were first observed displaying on the water in 1983, and in January 1988 there were 16-18 present when single birds were first observed landing on two of the rocks.  Twelve were seen near the rocks in February 1993 and in December 1999 from a helicopter I observed one Laysan roosting on South Rock (Roca Sur) and five on North Rock – one on the latter appeared to be incubating as it stayed in the same position for at least three hours.

A Laysan Albatross swims in the roiling foam among the rocks at Rocas Alijos

An apparently incubating Laysan Albatross is discernable on North Rock in the aerial photo's centre in December 1999

In December 2003, I counted 28 Laysan Albatrosses associated with the rocks. This is the highest count for the locality and the birds seemed to be either already breeding on North and South Rocks or just preparing to as birds were displaying on the water with three to four pairs considered to be breeding at the time.  Laysan Albatrosses occur seasonally at Rocas Alijos: none was seen during visits to the rocks in August 2006 and October 1993.

In addition to Laysan Albatrosses, a single Black-footed Albatross P. nigripes was observed around a boat at Rocas Alijos for two days in February 1993, and a minimum of three were flying between the rocks in December 1999.

Several other seabirds are known to breed on Rocas Alijos, including Red-billed Tropicbird Phaethon aethereus (strongly suspected), both Masked Sula dactylatra and Nazca S. granti Boobies, an as-yet unidentified frigatebird Fregata sp., Sooty Tern Onychoprion fuscata and an unidentified storm petrel Oceanodroma sp.

See ACAP Breeding Site accounts for the Mexican islands supporting breeding Laysan Albatrosses of Clarion, Revillagigedo Archipelago and Guadalupe.

All photographs by R.L. Pitman.

Selected References:

Everett, W.T. & Pitman, R.L. 1996.  Avian specimens from Rocas Alijos.  In: Schmieder, R.W. (Ed.).  Rocas Alijos.  Scientific Results from the Cordell Expeditions.  Dordrecht: Kluwer Academic Publishers.  pp. 359-362.

Howell, S.N.G. & Webb, S.W. 1992. Changing status of the Laysan Albatross in Mexico.  American Birds Summer 1992: 220-223.

Pitman, R.L. 1985.  The marine birds of Alijos Rocks, Mexico.  Western Birds 16: 81-92.

Pitman, R.L., Walker, W.A., Everett, W.T. & Gallo-Reynoso, J.P. 2004.  Population status, foods and foraging of Laysan Albatrosses Phoebastria immutabilis nesting on Guadalupe Island, Mexico. Marine Ornithology.

Senf, E. & Wicksten, M.K. 1996.  Birds observed at Rocas Alijos.  In: Schmieder, R.W. (Ed.).  Rocas Alijos.  Scientific Results from the Cordell Expeditions.  Dordrecht: Kluwer Academic Publishers.  pp. 355-357.

Bob Pitman, Southwest Fisheries Science Center, La Jolla, California, USA, 03 February 2013

Tanya Haupt (Department of Botany and Zoology, Stellenbosch University, South Africa) and colleagues write in the journal Polar Biology on why Wandering Albatross Diomedea exulans nests contain so many moth caterpillars.

The papers’ abstract follows:

“On the South Indian Ocean Province Islands of the sub-Antarctic, most nutrients are processed through a detritus-based food web.  On Marion Island, larvae of the moth Pringleophaga marioni are one of the key decomposers. Abundance of these caterpillars is higher in newly abandoned Wandering Albatross (Diomedea exulans) nests than other habitats, and this observation has been explained by hypotheses regarding the thermal and nutrient advantages of nests.  These hypotheses require a mechanism for increasing the abundance of caterpillars, since nests are an ephemeral resource, and here, we determine whether caterpillars respond to chemosensory and thermal cues using a laboratory choice chamber approach.  Caterpillars show no significant preference for newly abandoned nest material over no other choice, old nest material, and the common mire moss Sanionia uncinata.  Caterpillars that are acclimated to warm (15°C) conditions do prefer lower (5°C) to higher (15°C) temperatures, perhaps reflecting negative effects of prolonged exposure to warm temperatures on growth.  Caterpillars also show significant avoidance of conspecifics, possibly because of incidental cannibalism previously reported in this species.  Thus, we find no empirical support for nest-finding ability in caterpillars based on chemosensory or thermal cues.  It is possible that adult females or very early instar caterpillars show such ability, or high caterpillar density and biomass in nests are an incidental consequence of better conditions in the nests or deposition by the birds during nest construction.”

A Wanding Albatross chick on its nest at Marion Island

Photograph by John Cooper

Reference:

Haupt, T. Sinclair, B.J. & Chown, S.L. 2014.  Chemosensory and thermal cue responses in the sub-Antarctic moth Pringleophaga marioni: do caterpillars choose Wandering Albatross nest proxies?  Polar Biology DOI 10.1007/s00300-014-1457-2.

John Cooper, ACAP Information Officer, 02 February 2014

The Critically Endangered Tristan Albatross Diomedea dabbenena is perhaps the most threatened species listed within the Albatross and Petrel Agreement, facing as it does the twin threats of chick predation by mice ashore and longlining mortality at sea (click here).  In response BirdLife South Africa has declared the species to be its Bird of the Year for 2014 so as to increase publicity of its plight.

Tristan Albatross chick on Gough Island, a victim of attacks by mice

Photograph by Peter Ryan

“Seabirds, and albatrosses in particular, face a variety of daunting challenges.  They are becoming increasingly threatened and at a faster rate globally than any other group of birds. Many declines are closely linked to the expansion of commercial longline fisheries in seabird foraging areas, combined with the impacts of invasive alien species at nesting colonies.  The 2012 IUCN Red List reveals that the Tristan Albatross is the only Critically Endangered species that occurs annually in South African territory (including territorial waters).  The listing is a result of the bird’s extremely small breeding range (it is essentially a single-island endemic) and an exceptionally rapid projected population decline over three generations (70 years).  The population is decreasing through a combination of unsustainable deaths from tuna longline fishing and the incredible damage done by predatory, introduced mice at Gough Island, which are laying waste to around half the chicks produced every season.  Currently BirdLife South Africa is collaborating with the Percy FitzPatrick Institute at the University of Cape Town, tracking juvenile birds.  One of them recently entered South African waters, near Cape Town, and perhaps lucky birders on a pelagic trip could even see this individual in future!”

Other news from South Africa is that Professor John Croxall, Chairman of the BirdLife International’s Global Seabird Programme will be the guest speaker at BirdLife South Africa’s Annual General Meeting to be held at Mont-aux-Sources in South Africa’s Drakensberg Mountains in KwaZulu-Natal on 15 March 2014.  John has served on many national and international committees, notably as President of the British Ornithologists’ Union and Chairman of Council of the Royal Society for the Protection of Birds (RSPB).  He has received numerous awards, including appointment as CBE, election as a Fellow of the Royal Society, and receiving the President's and Godman-Salvin Medals of the British Ecological Society and the BOU, respectively. He is an Honorary Professor at the Universities of Birmingham and Durham, an Honorary Fellow of the American Ornithologists' Union and received the Lifetime Achievement Award from the Pacific Seabird Group in 2008.  John Croxall retired from a long and distinguished career studying southern seabirds with the British Antarctic Survey in 2006 but remains active in the conservation and management of seabirds and marine systems, especially with his participation in the Global Seabird Programme, as a member of the High Seas Task Force of the World Conservation Union (IUCN), and as a regular attendee at Sessions of ACAP’s Meeting of Parties and its Advisory Committee since 2001.

John Croxall conducting field work on Bird Island (with a Wandering Albatross behind)

Immediately before the AGM John and Alison Stattersfield, Head of Science at BirdLife International, will participate in LAB (Learn about Birds), a two-day interactive series of lectures, presentations and discussions co-hosted by BirdLife South Africa and the University of Cape Town's Percy FitzPatrick Institute of African Ornithology.

John Cooper, ACAP Information Officer, 01 February 2014

Deborah Pardo (British Antarctic Survey, Cambridge, United Kingdom and ACAP’s European News Correspondent) and colleagues write open-access in the journal Ecology and Evolution on ageing in Wandering Albatrosses Diomedea exulans.

The paper’s abstract follows:

“Allocation decisions depend on an organism’s condition which can change with age.  Two opposite changes in life-history traits are predicted in the presence of senescence: either an increase in breeding performance in late age associated with terminal investment or a decrease due to either life-history trade-offs between current breeding and future survival or decreased efficiency at old age.  Age variation in several life-history traits has been detected in a number of species, and demographic performances of individuals in a given year are influenced by their reproductive state the previous year.  Few studies have, however, examined state-dependent variation in life-history traits with aging, and they focused mainly on a dichotomy of successful versus failed breeding and nonbreeding birds.  Using a 50-year dataset on the long-lived quasi-biennial breeding wandering albatross, we investigated variations in life-history traits with aging according to a gradient of states corresponding to potential costs of reproduction the previous year (in ascending order): non-breeding birds staying at sea or present at breeding grounds, breeding birds that failed early, late or were successful.  We used multistate models to study survival and decompose reproduction into four components (probabilities of return, breeding, hatching, and fledging), while accounting for imperfect detection.  Our results suggest the possible existence of two strategies in the population: strict biennial breeders that exhibited almost no reproductive senescence and quasi-biennial breeders that showed an increased breeding frequency with a strong and moderate senescence on hatching and fledging probabilities, respectively.  The patterns observed on survival were contrary to our predictions, suggesting an influence of individual quality rather than trade-offs between reproduction and survival at late ages.  This work represents a step further into understanding the evolutionary ecology of senescence and its relationship with costs of reproduction at the population level.  It paves the way for individual-based studies that could show the importance of intra-population heterogeneity in those processes.”

An old Wanderer guards its chick, photograph by John Cooper

Click here to access earlier publications by Deborah Pardo on ageing in albatrosses, including her PhD thesis on the subject.

Reference:

Pardo, D., Barbraud, C. & Weimerskirch, H. 2014.  What shall I do now?  State-dependent variations of life-history traits with aging in Wandering Albatrosses.  Ecology and Evolution doi: 10.1002/ece3.882.

John Cooper, ACAP Information Officer, 31 January 2014