ACAP Latest News

Read about recent developments and findings in procellariiform science and conservation relevant to the Agreement on the Conservation of Albatrosses and Petrels in ACAP Latest News.

Beached fledglings have heavier plastic loads than do road-killed fledglings in the Short-tailed Shearwater

Airam Rodríguez (Conservation Department, Phillip Island Nature Parks, Cowes, Victoria, Australia) and colleagues have published in the journal Environmental Pollution on plastic pollution in the Short-tailed Shearwater Ardenna tenuirostris (Least Concern)

The paper’s abstract follows:

“Despite the increase of literature on seabird plastic ingestion in recent years, few studies have assessed how plastic loads vary according to different sampling methods. Most studies use necropsies of seabirds with a natural cause of death, e.g. beached or predated [sic], to determine plastic loads and monitor marine debris. Sampling naturally dead seabirds may be biased as they have perished because of their intrinsic factors, e.g. poor body condition, high parasite loads, sickness or predation, affecting estimates of plastic loads. However, seabirds killed accidentally may be more representative of the population. Here, we used the short-tailed shearwater Ardenna tenuirostris to test different sampling methods: naturally beached fledglings and accidentally road-killed fledglings after being attracted and grounded by artificial lights. We compared plastic load, body condition, and feeding strategies (through using feathers’ δ13C and δ15N isotope niche) between beached and road-killed fledglings. Beached birds showed higher plastic loads, poorer body condition and reduced isotopic variability, suggesting that this group is not a representative subsample of the whole cohort of the fledgling population. Our results might have implications for long-term monitoring programs of seabird plastic ingestion. Monitoring plastic debris through beached birds could overestimate plastic ingestion by the entire population. We encourage the establishment of refined monitoring programs using fledglings grounded by light pollution if available. These samples focus on known cohorts from the same population. The fledgling plastic loads are transferred from parents during parental feeding, accumulating during the chick-rearing period. Thus, these fledglings provide a higher and valuable temporal resolution, which is more useful and informative than unknown life history of beached birds.”

Short-tailed Shearwater at sea, photograph by Kirk Zufelt

Reference:

Rodríguez, A., Ramírez, F., Carrasco, M.N. & Chiaradia, A. 2018.  Seabird plastic ingestion differs among collection methods: examples from the short-tailed shearwater.  Environmental Pollution 243B: 1750-1757.

John Cooper, AAP Information Officer, 13 November 2018

The Tamini Tabla keeps bird-scaring lines away from trawl cables – and wins an award

The Marsh Award for Marine Conservation Leadership is made by the Marsh Christian Trust (MCT) in partnership with Fauna and Flora International (FFI) and “recognises people and organisations who are having a profound impact on marine conservation activities in the areas where they operate”.

The Award celebrates those who have been active in their communities, highlighting local leaders or organisations making a particularly special contribution to marine conservation through FFI’s organisational aims: securing the future of key threatened habitats and species; addressing root causes of biodiversity loss; assisting others in delivering conservational gains.

One of the two Marsh Marine Conservation Leadership Award recipients for 2018 is Leandro (Leo) Tamini of Albatross Task Force - Argentina, who has invented the Tamini Tabla (Tamini Table), a device that has the potential to reduce seabird mortality due to collision with trawl cables or warps.

A Tamini Tabla gets fitted for deployment on a bird-scaring line aboard a trawler, photograph by Leo Tamini

Luis reports in a BirdLife International news item: “One of my goals when I began working with the Albatross Task Force was to increase the usage of bird-scaring lines. This method [which involves using colorful streamers to ward birds away from trawl cables or longline hooks] is one of the simplest and most economical ways to reduce the instances of birds crashing into trawling cables. However, these lines can become tangled in the trawl cables, wearing them out and causing problems for fishing crews.  The solution was to design something that would weigh the bird-scaring lines down, to maintain the tension and keep the lines separated from the trawl cables. After pondering on the question for a while, and discarding a few ideas that wouldn’t work for technical reasons, I thought that we should try doing something like a miniature surfboard, with a keel at about 45 degrees to make sure the board stayed even. With the help of some crew I was able to put together a prototype from materials found on board the vessel. We tested it, and incredibly, it worked great! The lines were more taut and went out at about a 20 degree angle away from the vessel” (click here).

John Cooper, ACAP Information Officer, 12 November 2018

Inferring comparative foraging ecology of the Waved Albatross from isotope analysis

Gustavo Jiménez-Uzcátegui (Charles Darwin Research Station, Puerto Ayora, Galápagos, Ecuador) and colleagues have published in the open-access journal Marine Ornithology on the foraging ecology of three species of Galapagos seabirds studied by stable isotope analysis, including the globally Critically Endangered Waved Albatross Phoebastria irrorata.

The paper’s abstract follows:

“The Galápagos Penguin Spheniscus mendiculus, Flightless Cormorant Phalacrocorax harrisi, and Waved Albatross Phoebastria irrorata are endemic to Islas Galápagos. They are known to feed on different prey (including crustaceans, cephalopods, and/or several species of epipelagic and benthic fish), in accordance with different foraging strategies. In this work, we used stable-isotope analysis of carbon and nitrogen to corroborate available information on habitat use (δ13C) and trophic position (δ15N). Feather samples from the three species were collected in six different areas prior to the 2011 and 2012 breeding seasons. Results showed differences in foraging strategies between Galápagos Penguins and the other two species (δ13C and δ15N, P < 0.01). The Flightless Cormorant and Waved Albatross showed similar proportions of δ13C (P = 0.07), but they occupied different trophic levels (δ15N, P < 0.01).”

 

Statue of a Waved Albatross in Puerto Ayora, Santa Cruz, Galapagos; photograph by John Cooper

Reference:

Jiménez-Uzcátegui, G., Vaca, L., Cotín, J., García, C., Costales, A., Sevilla, C., & Páez-Rosas, D. 2019.  Using referential values of δ13C and δ15N to infer the foraging ecology of Galápagos seabirds.  Marine Ornithology 47: 5-10.

John Cooper, ACAP Information Officer, 09 November 2018

Burrow architecture of the Sooty Shearwater

Tyler Clark (Institute of Biodiversity, Animal Health, and Comparative Medicine, University of Glasgow, Scotland, UK) and colleagues have published open access in the ornithological journal Ibis on aspects of the burrows of Sooty Shearwaters Ardenna grisea.

The paper’s abstract follows:

“The Sooty Shearwater Ardenna grisea, an abundant but declining petrel, is one of many seabird species that construct breeding burrows, presumably because these confer protection from predators and the elements. Little is known about the causes of variation in Sooty Shearwater burrow architecture, which can differ markedly both within and between breeding sites. We hypothesize that varies in response to habitat type and competition for space. To address these hypotheses, we recorded Sooty Shearwater burrow dimensions on Kidney Island, the largest Sooty Shearwater colony in the Falkland Islands, South Atlantic, and modelled these as functions of burrow density (a proxy for competition) and habitat indices. Our models suggest that Sooty Shearwaters burrow further underground in response to competition for breeding space, and that soil underlying dense tussac grass Poa flabellata is more easily excavated than other substrates, indicating how vegetation restoration could aid the conservation of this species.”

 

Reference:Sooty Shearwater West Coast Penguin Trust s1

Sooty Shearwater, photograph from the West Coast Penguin Trust

Clark, T.J., Bonnet-Lebrun, A.-S., Campioni, L., Catry, P. & Wakefield, E. 2018.  The depth of Sooty Shearwater Ardenna grisea burrows varies with habitat and increases with competition for space.  Ibis doi.org/10.1111/ibi.12631.

John Cooper, ACAP Information Officer, 08 November 2018

Evidence for environmental specialisation among individual Grey-headed and Black-browed Albatrosses

Anne-Sophie Bonnet-Lebrun (Department of Zoology, University of Cambridge, UK) and colleagues have published open access in the journal Marine Biology on individual specialisation in at-sea distribution of satellite-tracked Black-browed Albatrosses Thalassarche melanophris and Grey-headed Albatrosses Thalassarche chrysostoma.

The paper’s abstract follows:

“Many predictive models of spatial and temporal distribution (e.g. in response to climate change or species introductions) assume that species have one environmental niche that applies to all individuals. However, there is growing evidence that individuals can have environmental preferences that are narrower than the species niche. Such individual specialization has mainly been studied in terms of dietary niches, but a recent increase in the availability of individual movement data opens the possibility of extending these analyses to specialisation in environmental preferences. Yet, no study to date on individual specialisation has considered the environmental niche in its multidimensionality. Here we propose a new method for quantifying individual specialisation in multiple dimensions simultaneously. We compare the hypervolumes in n-dimensional environmental niche space of each individual against that of the population, testing for significant differences against a null model. The same method can be applied to a 2-dimensional geographic space to test for site fidelity. We applied this method to test for individual environmental specialisation (across three dimensions: sea surface temperature, eddy kinetic energy, depth) and for site fidelity among satellite-tracked black-browed albatrosses (Thalassarche melanophris) and grey-headed albatrosses (Thalassarche chrysostoma), during chick-rearing at South Georgia. We found evidence for site fidelity in both species and of environmental specialisation among individual grey-headed but not black-browed albatrosses. Specialisation can affect the resilience of populations affected by natural and anthropogenic changes in the environment, and hence has implications for population dynamics and conservation.”

 

Grey-headed Albatross, photograph by Kirk Zufelt

Reference:

Bonnet-Lebrun, A.-S., Phillips, R.A., Manica, A & Rodrigues, A.S.L. 2018.  Quantifying individual specialization using tracking data: a case study on two species of albatrosses.  Marine Biology doi.org/10.1007/s00227-018-3408-x.

John Cooper, ACAP Information Officer, 07 November 2018

The Agreement on the
Conservation of Albatrosses and Petrels

ACAP is a multilateral agreement which seeks to conserve listed albatrosses, petrels and shearwaters by coordinating international activity to mitigate known threats to their populations.

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