ALBERT

Description: Ecological Applications, Volume 0, Issue 0, Ahead of Print. Recent changes in sanitary policies by European Union (EU) concerning disposal of carcasses of domestic animals and the increase of non-natural mortality factors as illegal poisoning are threatening European vultures. However, the effects of anthropogenic actions in demographic parameters are poorly studied. Using a long-term study (1994-2011) of the threatened Pyrenean bearded vulture Gypaetus barbatus population, we assess the variation in the proportion of breeding pairs, egg-laying dates, clutch size, productivity, breeding success and survival following a sharp reduction in food availability in 2005. To test such variations we used Cusum tests (from the field of statistical process control) and multi-event capture-recapture modeling to estimate changes in survival probabilities. We found a delay in laying dates, and a regressive trend in clutch size, productivity, flight rate and survival. The maintenance of specific supplementary feeding stations for bearded vultures likely reduced the negative effects of illegal poisoning and food shortages, which mainly affected sub-adult survival. According to the Cusum test, demographic parameters suffered a significant shift after 2005 coinciding with a reduction in the food supply for the avian scavenger guild. Changes in food availability may have produced changes in demographic parameters and an increase in mortality due to an increased exposure to contaminated food. As a result supplementary feeding used as a precautionary measure can be a useful tool to reduce illegal poisoning and shifts in demographic parameters until precedent food availability scenarios are achieved. This study shows how anthropogenic actions through human health regulations affecting habitat quality can suddenly modify demographic parameters in long-lived raptors. Because in natural processes the variation of biological parameters is usually slow and gradual, and because randomness and environmental stochasticity makes it difficult to detect changes in the absence of a large number of records, the use of Cusum test constitutes a useful tool for studies in the field of ecology and evolution.

Description: Ecological Applications, Volume 24, Issue 3, Page 436-444, April 2014. Recent changes in sanitary policies within the European Union (EU) concerning disposal of carcasses of domestic animals and the increase of non-natural mortality factors, such as illegal poisoning, are threatening European vultures. However, the effects of anthropogenic activities on demographic parameters are poorly studied. Using a long-term study (1994–2011) of the threatened Pyrenean Bearded Vulture Gypaetus barbatus population, we assess the variation in the proportion of breeding pairs, egg-laying dates, clutch size, breeding success, and survival following a sharp reduction in food availability in 2005 due to the application of restrictive sanitary policies decreasing livestock carcass availability. We found a delay in laying dates and a regressive trend in clutch size, breeding success, and survival following policy change. The maintenance of specific supplementary feeding stations for Bearded Vultures probably reduced the negative effects of illegal poisoning and food shortages, which mainly affected subadult survival. A drop in food availability may have produced changes in demographic parameters and an increase in mortality due to an increased exposure to contaminated food. As a result, supplementary feeding as a precautionary measure can be a useful tool to reduce illegal poisoning and declines in demographic parameters until previous food availability scenarios are achieved. This study shows how anthropogenic activities through human health regulations that affect habitat quality can suddenly modify demographic parameters in long-lived species, including those, such as survival, with high sensitivity to population growth rate.

Description: Recent changes in sanitary policies within the European Union (EU) concerning disposal of carcasses of domestic animals and the increase of non-natural mortality factors, such as illegal poisoning, are threatening European vultures. However, the effects of anthropogenic activities on demographic parameters are poorly studied. Using a long-term study (1994?2011) of the threatened Pyrenean Bearded Vulture Gypaetus barbatus population, we assess the variation in the proportion of breeding pairs, egg-laying dates, clutch size, breeding success, and survival following a sharp reduction in food availability in 2005 due to the application of restrictive sanitary policies decreasing livestock carcass availability. We found a delay in laying dates and a regressive trend in clutch size, breeding success, and survival following policy change. The maintenance of specific supplementary feeding stations for Bearded Vultures probably reduced the negative effects of illegal poisoning and food shortages, which mainly affected subadult survival. A drop in food availability may have produced changes in demographic parameters and an increase in mortality due to an increased exposure to contaminated food. As a result, supplementary feeding as a precautionary measure can be a useful tool to reduce illegal poisoning and declines in demographic parameters until previous food availability scenarios are achieved. This study shows how anthropogenic activities through human health regulations that affect habitat quality can suddenly modify demographic parameters in long-lived species, including those, such as survival, with high sensitivity to population growth rate. # doi:10.1890/13-0414.1