Active breeding seabirds prospect alternative breeding colonies.

Compared to other animal movements, prospecting by adult individuals for a future breeding site is commonly overlooked. Prospecting influences the decision of where to breed and has consequences on fitness and lifetime reproductive success. By analysing movements of 31 satellite- and GPS-tracked gull and tern populations belonging to 14 species in Europe and North America, we examined the occurrence and factors explaining prospecting by actively breeding birds.

Insular holobionts: persistence and seasonal plasticity of the Balearic wall lizard ( gut microbiota.

Background: Integrative studies of animals and associated microbial assemblages (, the holobiont) are rapidly changing our perspectives on organismal ecology and evolution. Insular vertebrates provide ideal natural systems to understand patterns of host-gut microbiota coevolution, the resilience and plasticity these microbial communities over temporal and spatial scales, and ultimately their role in the host ecological adaptation.

Methods: Here we used the endemic Balearic wall lizard to dissect the drivers of the microbial diversity within and across host allopatric populations/islets.

Life span, growth, senescence and island syndrome: Accounting for imperfect detection and continuous growth.

Small vertebrates on islands are expected to attain a larger body size, and a greater survival than their mainland counterparts. Comparative studies have questioned whether lizards exhibit this set of adaptations, referred to as the 'island syndrome'. We collected data on 730 individuals the endemic Lilford's lizard Podarcis lilfordi throughout a 10-year period on a small island of the Balearic archipelago (Spain).

Interspecific synchrony on breeding performance and the role of anthropogenic food subsidies.

Synchrony can have important consequences for long-term metapopulations persistence, community dynamics and ecosystems functioning. While the causes and consequences of intra-specific synchrony on population size and demographic rates have received considerable attention only a few factors that may affect inter-specific synchrony have been described. We formulate the hypothesis that food subsidies can buffer the influence of environmental stochasticity on community dynamics, disrupting and masking originally synchronized systems.

It's not all abundance: Detectability and accessibility of food also explain breeding investment in long-lived marine animals.

Large-scale climatic indices are extensively used as predictors of ecological processes, but the mechanisms and the spatio-temporal scales at which climatic indices influence these processes are often speculative. Here, we use long-term data to evaluate how a measure of individual breeding investment (the egg volume) of three long-lived and long-distance-migrating seabirds is influenced by i) a large-scale climatic index (the North Atlantic Oscillation) and ii) local-scale variables (food abundance, foraging conditions, and competition). Winter values of the North Atlantic Oscillation did not correlate with local-scale variables measured in spring, but surprisingly, both had a high predictive power of the temporal variability of the egg volume in the three study species, even though they have different life-history strategies.

Global political responsibility for the conservation of albatrosses and large petrels.

Migratory marine species cross political borders and enter the high seas, where the lack of an effective global management framework for biodiversity leaves them vulnerable to threats. Here, we combine 10,108 tracks from 5775 individual birds at 87 sites with data on breeding population sizes to estimate the relative year-round importance of national jurisdictions and high seas areas for 39 species of albatrosses and large petrels. Populations from every country made extensive use of the high seas, indicating the stake each country has in the management of biodiversity in international waters.

Contrasting size-dependent life history strategies of an insular lizard.

In many species with continuous growth, body size is an important driver of life-history tactics and its relative importance is thought to reflect the spatio-temporal variability of selective pressures. We developed a deterministic size-dependent integral projection model for 3 insular neighboring lizard populations with contrasting adult body sizes to investigate how size-related selective pressures can influence lizard life-history tactics. For each population, we broke down differences in population growth rates into contributions from size-dependent body growth, survival, and fecundity.

Diet composition of the lizard (Lacertidae) on 2 small islands: an individual-resource network approach.

Despite it is widely accepted that intrapopulation variation is fundamental to ecological and evolutionary processes, this level of information has only recently been included into network analysis of species/population interactions. When done, it has revealed non-random patterns in the distribution of trophic resources. Nestedness in resource use among individuals is the most recurrent observed pattern, often accompanied by an absence of modularity, but no previous studies examine bipartite modularity.

Infestation of small seabirds by Ornithodoros maritimus ticks: Effects on chick body condition, reproduction and associated infectious agents.

Ticks can negatively affect their host by direct effects as blood feeding causing anaemia or discomfort, or by pathogen transmission. Consequently, ticks can have an important role in the population dynamics of their hosts. However, specific studies on the demographic effects of tick infestation on seabirds are still scarce.

Differential adult survival at close seabird colonies: The importance of spatial foraging segregation and bycatch risk during the breeding season.

Marine megafauna, including seabirds, are critically affected by fisheries bycatch. However, bycatch risk may differ on temporal and spatial scales due to the uneven distribution and effort of fleets operating different fishing gear, and to focal species distribution and foraging behavior. Scopoli's shearwater Calonectris diomedea is a long-lived seabird that experiences high bycatch rates in longline fisheries and strong population-level impacts due to this type of anthropogenic mortality.

Varying demographic impacts of different fisheries on three Mediterranean seabird species.

Fisheries have an enormous economic importance, but reconciling their socio-economic features with the conservation and sustainability of marine ecosystems presents major challenges. Bycatch mortality from fisheries is clearly among the most serious global threats for marine ecosystems, affecting a wide range of top predators. Recent estimates report ca.

Climate-driven vital rates do not always mean climate-driven population.

Current climatic changes have increased the need to forecast population responses to climate variability. A common approach to address this question is through models that project current population state using the functional relationship between demographic rates and climatic variables. We argue that this approach can lead to erroneous conclusions when interpopulation dispersal is not considered.

Population control of an overabundant species achieved through consecutive anthropogenic perturbations.

The control of overabundant vertebrates is often problematic. Much work has focused on population-level responses and overabundance due to anthropogenic subsidies. However, far less work has been directed at investigating responses following the removal of subsidies.

Population structure and dispersal patterns within and between Atlantic and Mediterranean populations of a large-range pelagic seabird.

Dispersal is critically linked to the demographic and evolutionary trajectories of populations, but in most seabird species it may be difficult to estimate. Using molecular tools, we explored population structure and the spatial dispersal pattern of a highly pelagic but philopatric seabird, the Cory's shearwater Calonectris diomedea. Microsatellite fragments were analysed from samples collected across almost the entire breeding range of the species.

Studying the reproductive skipping behavior in long-lived birds by adding nest inspection to individual-based data.

The frequency at which individuals breed is an important parameter in population, as well as in evolutionary, studies. However, when nonbreeding individuals are absent from the study area, the reproductive skipping is usually confounded with a recapture failure and cannot be estimated directly. Yet, there are situations in which external information may help to estimate reproductive skipping.

Foraging segregation between two closely related shearwaters breeding in sympatry.

Trophic segregation has been proposed as a major mechanism explaining the coexistence of closely related animal taxa. However, how such segregation varies throughout the annual cycle is poorly understood. Here, we examined the feeding ecology of the two subspecies of Cory's shearwater, Calonectris diomedea diomedea and Calonectris diomedea borealis, breeding in sympatry in a Mediterranean colony.

Buying years to extinction: is compensatory mitigation for marine bycatch a sufficient conservation measure for long-lived seabirds?

Along the lines of the 'polluter pays principle', it has recently been proposed that the local long-line fishing industry should fund eradication of terrestrial predators at seabird breeding colonies, as a compensatory measure for the bycatch caused by the fishing activity. The measure is economically sound, but a quantitative and reliable test of its biological efficacy has never been conducted. Here, we investigated the demographic consequences of predator eradication for Cory's shearwater Calonectris diomedea, breeding in the Mediterranean, using a population model that integrates demographic rates estimated from individual life-history information with experimental measures of predation and habitat structure.