Polar Regions are experiencing environmental changes at unprecedented rates. ese changes can spread throughout entire food webs from lower trophic levels to apex predators. As many top predators forage over large areas, these indirect e ects may be associated with large-scale patterns of climate variability. Using global climate indices that are known to impact the Southern Ocean ecosystem (the El Niño Southern Oscillation and Antarctic Oscillation Indices) we assessed their e cacy to predict variation in the demographic parameters of Antarctic seabirds. First, we used a long-term dataset on adult survival (estimated from capture–mark–recapture data) and reproduction of Antarctic petrel alassoica antarctica, from the largest known breeding colony (Svarthamaren, Dronning Maud Land) and examined whether large-scale oceanographic uctuations impact survival and reproduction. Second, we conducted an exhaustive literature review to determine whether the e ects of large-scale environmental variability on Antarctic seabirds have a coherent ngerprint across the Antarctic continent and nearby islands. We found that most of the variation in both reproductive success, timing of hatching, and survival of Antarctic petrels can be accurately modeled using the two modes of large-scale climate variability in Antarctica. e literature review, combined with the results from our eld study, suggests that while the anticipated trends in the global patterns of climatic variability will generally have detrimental e ects on populations of top predators in the Southwest Atlantic, these conclusions cannot be extrapolated to all seabird populations in Antarctica without additional data.
Número de documento:
Dr Andrew Lowther (Noruega)
Dr Olav Rune Godø (Noruega)
Punto(s) de la agenda
Ecography, 39 (2016): 496–505, doi: 10.1111/ecog.01659