Monday, 24 June 2019

Urban ecology on Air!

Álvaro Luna at "Balears Fa Ciència" (here, min 27) speaking on Urban Ecology and Urban Evolution. Álvaro is finishing his PhD at the University of Sevilla, co-supervised by M. Carrete from the University of Sevilla and A. Sanz-Aguilar from the GEDA (IMEDEA -CSIC/UIB). 
His research is focussing on the adaptation and the ecology of urban fauna. Here is a previous post on Alvaro's book, with an interview by E. Soto.

Friday, 14 June 2019

New Publication on poaching related mortality !

Corlatti, L., Sanz-Aguilar, A., Tavecchia, G., Giugiatti A., and Pedrotti, L., 2019 Unrevelling the sex- and age-specific impact of poaching mortality with multievent modeling Frontiers in Zoology,

Abstract:  Poaching is a prominent source of ‘hidden hurdles’, cryptic impacts of human activities that may hinder the conservation of animal populations. Estimating poaching mortality is challenging, as the evidence for illegal killing is not outwardly obvious. Using resighting and recovery data collected on 141 marked red deer Cervus elaphus within the Stelvio National Park (central Italian Alps), we show how multievent models allow to assess the direct impacts of illegal harvesting on age- and sex-specific survival, accounting for uncertainty over mortality causes.

Mortality caused by poaching was consistently higher for males than for females in all age classes. In males, the probability of dying from poaching was higher for extreme age classes, while in females all age classes showed fairly similar values of poaching mortality. The strong bias in sex-specific poaching mortality was possibly due to trophy killing in adult males and ‘bushmeat-like’ killing for private or commercial gain in young males and in females.

A robust assessment of age- and sex-specific prevalence of poaching in wildlife populations is pivotal when illegal killing is of conservation concern. This provides timely information on what segment of the population is most likely to be affected. Besides obvious demographic consequences on small populations, age- and sex-biased poaching prevalence may contrast with the need to maintain ecosystem complexity and may alter behavioral responses to human presence. The information provided by multievent models, whose flexibility makes them adaptable to many systems where individual-based data is part of population monitoring, offers a support to design appropriate strategies for the conservation of wildlife populations.

Saturday, 8 June 2019

New publication on Lilfordi's lizard !

Santamaría, S., Enoksen, C. A., Olsen, J., Tavecchia, G., Rotger, A., Igual, J.M. and Traveset A. 2019.Diet composition of the lizard Podarcis lilfordi (Lacertidae) on two small islands: an individual-resource network approach. Current Zoology,

Abstract: 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. We use network analysis to describe the diet composition of the Balearic endemic lizard Podarcis lilfordi in two islets at population and individual levels, based on the occurrence of food items in fecal samples.
Our objectives are to 1) compare niche structure at both levels, 2) characterize niche partition using nestedness and modularity, and 3) assess how size, sex, season, and spatial location influence niche structure. At population-level niche width was wide, but narrow at the level of the individual. Both islet networks were nested, indicating similar ranking of the food preferences among individuals, but also modular, which was partially explained by seasonality. Sex and body size did not notably affect diet composition. Large niche overlap and therefore possibly relaxed competition were observed among females in one of the islets and during spring on both islets. Likewise, higher modularity in autumn suggests that higher competition could lead to specialization in both populations, because resources are usually scarce in this season. The absence of spatial location influence on niche might respond to fine-grained spatio-temporally distribution of food resources. Behavioral traits, not included in this study, could also influence resource partitioning.

Tuesday, 4 June 2019

The Storm Petrel on the Virtual Encyclopedia of Vertebrates!

A. Sanz-Aguilar led a team of six researchers to write the chapter on the European Storm Petrel for the Virtual Encyclopedia of Spanish Vertebrates. The result is one of the richest and more accurate work available on this species, reporting findings from 170 references on Storm Petrel habitat, distribution, diet and demography. A work the summarizes information collected during many years of research at several European sites.


Lizard campaign just started!

  The first island has been sampled. Likely we had good weather and animals were collaborating. Looking forward to calculate an estimate of ...