The 2018 spring campaign of Yellow legged gull at Dragonera natural park is getting to its peak. Today we set traps, measured eggs and search for marked individuals. This year, thank to M. Gomila, we are going to add some extra readings by using a digital zoom (and great skills!) .
Abstract: Reproductive timing in many taxa plays a key role in determining breeding productivity, and is often sensitive to climatic conditions.
Current climate change may alter the timing of breeding at different
rates across trophic levels, potentially resulting in temporal mismatch
between the resource requirements of predators and their prey.
This is of particular concern for higher-trophic-level organisms, whose
longer generation times confer a lower rate of evolutionary rescue than
primary producers or consumers. However, the disconnection between studies of ecological change in
marine systems makes it difficult to detect general changes in the
timing of reproduction.
Here, we use a comprehensive meta-analysis of 209 phenological time
series from 145 breeding populations to show that, on average, seabird
populations worldwide have not adjusted their breeding seasons over time
(−0.020 days yr−1) or in response to sea surface temperature (SST) (−0.272 days °C−1)
between 1952 and 2015. However, marked between-year variation in timing
observed in resident species and some Pelecaniformes and Suliformes
(cormorants, gannets and boobies) may imply that timing, in some cases,
is affected by unmeasured environmental conditions. This limited
temperature-mediated plasticity of reproductive timing in seabirds
potentially makes these top predators highly vulnerable to future
mismatch with lower-trophic-level resources.
Ainara Cortes from the GEDA participted at the international workshop on Egyptian vulture in the Western European flyway held in Alcantara the 26th-27th of March 2018. An important meeting organized by the Vulture Conservation Fundation (VCF) to set conservation priorities and coordinating management actions.
Payo-Payo, A., Sanz-Aguilar, A., Gaglio, D., Sherley, R.B.,Cook, T.R., Altwegg, R. and Ryan, P.G. 2018 Survival estimates for the greater crested tern Thalasseus bergii in southern AfricaAfrican Journal of Marine Science, 40. 45-50, doi: https://doi.org/10.2989/1814232X.2018.1437470 Abstract: The nominate race of the greater crested tern Thalasseus bergii
breeds only along the coast of the Benguela region (west coast) of
southern Africa, where its population is increasing, in contrast to
other species of breeding seabirds in the region which similarly depend
on forage fish. Although this population’s trends are well known, its
demographic parameters remain obscure. We used multi-event
capture–recapture–recovery modelling to provide the first estimates of
survival. The survival rate of birds older than two years was 0.93
(0.91–0.95); second-year survival was 0.93 (0.90–0.95) and first-year
survival was 0.80 (0.73–0.85). A resighting of a 34-year-old bird is a
new longevity record for the species. Population growth rates projected
with a Leslie matrix model that included our survival estimates were
very similar to estimates from annual counts of the breeding population
(7–8% y−1), suggesting that these survival estimates
adequately describe the species’ demography. High survival rates have
likely contributed to the species’ recent population increase in the
The study made the journal cover. Congrats Ana & Ana (& Co.)