A framework for mapping the distribution of Southern Ocean seabirds across life-history stages, by integrating tracking, demography and phenology.

• Published in: Journal of Applied Ecology
• Main Authors: Carneiro, Ana P. B., Pearmain, Elizabeth J., Oppel, Steffen, Clay, Thomas A., Phillips, Richard A., Bonnet‐Lebrun, Anne-Sophie, Wanless, Ross M., Abraham, Edward, Richard, Yvan, Rice, Joel, Handley, Jonathan, Davies, Tammy E., Dilley, Ben J., Ryan, Peter G., Small, Cleo, Arata, Javier, Arnould, John P.Y., Bell, Elizabeth, Bugoni, Leandro, Campioni, Letizia, Catry, Paulo, Cleeland, Jaimie, Deppe, Lorna, Elliott, Graeme, Freeman, Amanda, González-Solís, Jacob, Granadeiro, José Pedro, Gremillet, David, Landers, Todd J., Makhado, Azwianewi, Nel, Deon, Nicholls, David G., Rexer-Huber, Kalinka, Robertson, Christopher J. R., Sagar, Paul M., Scofield, Paul, Stahl, Jean-Claude, Stanworth, Andrew, Stevens, Kim L., Trathan, Phil N., Thompson, David R., Torres, Leigh, Walker, Kath, Waugh, Susan M., Weimerskirch, Henri, Dias, Maria P.
• Format: Article in Journal/Newspaper
• Language: English
• Published: American Geophysical Union 2020
• Subjects: Southern Ocean
• Online Access: http://nora.nerc.ac.uk/id/eprint/526079/; https://nora.nerc.ac.uk/id/eprint/526079/1/Journal%20of%20Applied%20Ecology%20-%202020%20-%20Carneiro%20-%20A%20framework%20for%20mapping%20the%20distribution%20of%20seabirds%20by%20integrating%20tracking.pdf; https://besjournals.onlinelibrary.wiley.com/doi/10.1111/1365-2664.13568

1. The identification of geographic areas where the densities of animals are highest across their annual cycles is a crucial step in conservation planning. In marine environments, however, it can be particularly difficult to map the distribution of species, and the methods used are usually biased towards adults, neglecting the distribution of other life‐history stages even though they can represent a substantial proportion of the total population. 2. Here we develop a methodological framework for estimating population‐level density distributions of seabirds, integrating tracking data across the main life‐history stages (adult breeders and non‐breeders, juveniles and immatures). We incorporate demographic information (adult and juvenile/immature survival, breeding frequency and success, age at first breeding) and phenological data (average timing of breeding and migration) to weight distribution maps according to the proportion of the population represented by each life‐history stage. 3. We demonstrate the utility of this framework by applying it to 22 species of albatrosses and petrels that are of conservation concern due to interactions with fisheries. Because juveniles, immatures and non‐breeding adults account for 47%–81% of all individuals of the populations analysed, ignoring the distributions of birds in these stages leads to biased estimates of overlap with threats, and may misdirect management and conservation efforts. Population‐level distribution maps using only adult distributions underestimated exposure to longline fishing effort by 18%–42%, compared with overlap scores based on data from all life‐history stages. 4. Synthesis and applications. Our framework synthesizes and improves on previous approaches to estimate seabird densities at sea, is applicable for data‐poor situations, and provides a standard and repeatable method that can be easily updated as new tracking and demographic data become available. We provide scripts in the R language and a Shiny app to facilitate future applications of our ...