Morales J.,CSIC - National Museum of Natural Sciences |
Ruuskanen S.,University of Turku |
Laaksonen T.,University of Turku |
Eeva T.,University of Turku |
And 17 more authors.
Journal of Avian Biology | Year: 2013
The expression and impact of maternal effects may vary greatly between populations and environments. However, little is known about large-scale geographical patterns of variation in maternal deposition to eggs. In birds, as in other oviparous animals, the outermost maternal component of an egg is the shell, which protects the embryo, provides essential mineral resources and allows its interaction with the environment in the form of gas exchange. In this study, we explored variation of eggshell traits (mass, thickness, pore density and pigmentation) across 15 pied flycatcher populations at a large geographic scale. We found significant between-population variation in all eggshell traits, except in pore density, suggesting spatial variation in their adaptive benefits or in the females' physiological limitations during egg laying. Between- population variation in shell structure was not due to geographic location (latitude and longitude) or habitat type. However, eggshells were thicker in populations that experienced higher ambient temperature during egg laying. This could be a result of maternal resource allocation to the shell being constrained under low temperatures or of an adaptation to reduce egg water loss under high temperatures. We also found that eggshell colour intensity was positively associated with biliverdin pigment concentration, shell thickness and pore density. To conclude, our findings reveal large- scale between-population variation of eggshell traits, although we found little environmental dependency in their expression. Our findings call for further studies that explore other environmental factors (e.g. calcium availability and pollution levels) and social factors like sexual selection intensity that may account for differences in shell structure between populations. © 2013 The Authors. Journal of Avian Biology © 2013 Nordic Society Oikos.
Delibes-Mateos M.,Institute Of Investigacion En Recursos Cinegeticos Irec |
Giergiczny M.,University of Warsaw |
Caro J.,Institute Of Investigacion En Recursos Cinegeticos Irec |
Vinuela J.,Institute Of Investigacion En Recursos Cinegeticos Irec |
And 2 more authors.
Biological Conservation | Year: 2014
In southern Europe, traditional hunting has been frequently replaced by models based on more intensive management. These systems include management strategies like the release of farm-reared animals that can cause harmful effects on biodiversity. However, little is known about the hunters' views of this activity, and about their preferences for the ecological attributes of the hunting estates. We present the results of a choice experiment exercise evaluating the willingness to pay of Spanish hunters regarding different aspects of walked-up red-legged partridge (Alectoris rufa) shooting, including partridge quality (farm-reared vs. wild) and other attributes related to the ecological characteristics of the estate. We find that, when given the choice, hunting an additional wild partridge in a walked-up shooting day was valued more than 20. times higher than hunting an additional farm-reared bird. The diversity of small game available and the presence of natural vegetation in the landscape in which the walked-up hunting takes place were also significantly valued. Hunters also attributed economic value (albeit lower than other attributes) to the presence of protected non-game fauna in the estate. Overall, our results show that hunters are willing to pay more for hunting on estates that have better ecological characteristics, which may be indicative of good conservation status. This suggests that identifying and promoting such estates could lead to systems that are both ecologically and economically sustainable. © 2014 Elsevier Ltd.
Does fox control improve red-legged partridge (Alectoris rufa) survival? an experimental study in Northern Spain [¿puede el control de zorros mejorar la supervivencia de la perdiz roja (alectoris rufa)? un estudio experimental en el Norte de España]
Mateo-Moriones A.,Institute Of Investigacion En Recursos Cinegeticos Irec |
Villafuerte R.,Institute Of Investigacion En Recursos Cinegeticos Irec |
Ferreras P.,Institute Of Investigacion En Recursos Cinegeticos Irec
Animal Biodiversity and Conservation | Year: 2012
This work evaluates the effectiveness of fox control as a method to improve the survival of red-legged partridge (Alectoris rufa). We radio-tracked 89 adult partridges and their chicks (62 few days old chicks and 46 over one-month-old chicks) and monitored their nests (N = 45) on two hunting estates in northern Spain over two years. Generalist predators (red fox, Vulpes vulpes, and magpie, Pica pica) were selectively controlled on one half of each estate during the first year, and on the other half in the second year. We estimated the effect of predator control on survival rates. Predator control did not improve survival rates for adult partridges and nests, but it improved chick survival, especially for chicks over one-month old. © 2012 Museu de Ciències Naturals de Barcelona.