2024-03-28T21:50:02Zhttp://digital.csic.es/dspace-oai/requestoai:digital.csic.es:10261/1644112020-01-28T12:10:46Zcom_10261_88com_10261_8col_10261_341
00925njm 22002777a 4500
dc
Oro, Daniel
author
Álvarez, David
author
Velando, Alberto
author
2018
Environmental drivers, including anthropogenic impacts, affect vital rates of
organisms. Nevertheless, the influence of these drivers may depend on the physical features of
the habitat and how they affect life history strategies depending on individual covariates such
as age and sex. Here, the long-term monitoring (1994–2014) of marked European Shags in
eight colonies in two regions with different ecological features, such as foraging habitat,
allowed us to test several biological hypotheses about how survival changes by age and sex in
each region by means of multi-event capture–recapture modeling. Impacts included fishing
practices and bycatch, invasive introduced carnivores and the severe Prestige oil spill. Adult
survival was constant but, unexpectedly, it was different between sexes. This difference was
opposite in each region. The impact of the oil spill on survival was important only for adults
(especially for females) in one region and lasted a single year. Juvenile survival was time dependent
but this variability was not synchronized between regions, suggesting a strong signal of
regional environmental variability. Mortality due to bycatch was also different between sex,
age and region. Interestingly the results showed that the size of the fishing fleet is not necessarily
a good proxy for assessing the impact of bycatch mortality, which may be more dependent
on the fishing grounds and the fishing gears employed in each season of the year. Anthropogenic
impacts affected survival differently by age and sex, which was expected for a longlived
organism with sexual size dimorphism. Strikingly, these differences varied depending on
the region, indicating that habitat heterogeneity is demographically important to how environmental
variability (including anthropogenic impacts) and resilience influence population
dynamics.
Ecological Applications 28(3) : 612-621(2018)
1051-0761
http://hdl.handle.net/10261/164411
Resilience
Survival
Anthropogenic impacts
Habitat heterogeneity
Life histories
Long-lived species
Complex demographic heterogeneity from anthropogenic impacts in a coastal marine predator