Sources of variation in mortality of the Bearded Vulture Gypaetus barbatus in Europe

Abstract

SummaryWe analyse the causes of mortality for the Bearded Vulture in Europe. Shooting (31%), intentional poisoning (26%), collision (18%) and unintentional poisoning (12%) were the most important causes of mortality. No differences were found between sexes or age classes (nonadults and adults) for any of the causes of death. When the four main categories of mortality were grouped in periods of 3 years from 1986 (coinciding with the species' reintroduction to the Alps) to 2006, mortality showed significant temporal variation. The results suggest that while the number of collision/electrocution deaths has remained stable or increased slightly, the number of cases of shooting has declined during the last 6 years, while at the same time intentional and unintentional poisonings have increased. We found substantial differences between causes of mortality recorded for birds located by chance (75% related to shootings and collisions with powerlines) and radio-tagged birds (86% related to intentional and unintentional poisoning), suggesting biases in methodology for monitoring mortality. The results suggest that human persecution continues to be the main factor contributing to unnatural mortality for European Bearded Vultures. Future management actions should concentrate on the creation of protocols for the collection of carcasses and detailed analyses to determine and mitigate anthropogenic sources of mortality.

Anthropogenic activities influence the abandonment of Bearded Vulture (Gypaetus barbatus) territories in southern Africa

“…For example, causes of mortality of Bearded Vulture carcasses collected in the study area over a similar time period indicated that death was almost entirely a result of anthropogenic factors, with more than half attributed to indirect and accidental poisoning and persecution, and almost a quarter to power line collisions (S. C. Krüger personal observation). Similarly, non-natural mortalities attributed to illegal poisoning were the main mortality factors in other Bearded Vulture populations (Margalida et al 2008) and other large raptor populations (Whitfield et al 2004, Smart et al 2010, and collisions with power lines are known to threaten other vulture species in Africa (Smallie andVirani 2010, Boshoff et al 2011). Impacts related to human disturbance were also found to limit the distribution patterns of Bearded Vulture and other large raptor breeding ranges, densities, and foraging areas (Brown 1988, Herremans and Herremans-Tonnoeyr 2000, Donázar et al 2002, Bautista et al 2004, Gavashelishivili and McGrady 2006, Margalida et al 2007).…”

“…Vultures in particular have experienced large population declines worldwide as a result of loss of suitable breeding and foraging habitat and poisoning , Oaks et al 2004, Ogada et al 2012. The Bearded Vulture (Gypaetus barbatus; Figure 1) is also showing declines throughout much of its range (Mingozzi and Estève 1997, Margalida et al 2008, Birdlife International 2012. Within southern Africa, where the breeding population has declined in both numbers (32-51%) and range (27%) over the past 5 decades (Krüger et al 2014), the species was recently up-listed to Critically Endangered (Krüger in press).…”

“…Global vulture declines and declines in Bearded Vulture populations have largely been attributed to human impacts, namely human persecution for traditional medicine, food, ceremonies, and other purposes (Maphisa 1997, Xirouchakis et al 2001, Mander et al 2007, Thiollay 2007; indirect poisoning through poison baiting of carnivores (Brown 1991) and use of veterinary drugs , Oaks et al 2004; collisions with power lines (Krüger et al 2006); or a combination of these factors (Margalida et al 2008, Ogada et al 2012.…”

Dietary shifts in two vultures after the demise of supplementary feeding stations: consequences of the EU sanitary legislation

“…Moreover, there would be fewer incidences of other negative factors threatening the populations of carrion eaters depending on intensive livestock such as the ingestion of veterinary drugs and pathogen transmission (Blanco et al 2007;Lemus et al 2008). Also, a higher availability of carcasses would reduce the probability of ingestion of poisoned preys (Margalida et al 2008). It is necessary for EU legislation and the regulation of the states and regions to have enough flexibility to authorize owners of extensive operations to abandon the carcasses of their livestock in order to sustain populations of avian scavengers (Donázar et al 2009b).…”

Shooting is still a main threat for raptors inhabiting urban and suburban areas of Rome, Italy

“…So far, most of the studies on the causes of mortality of wild raptors have focused on single species (Real et al 2001;González et al 2007;Margalida et al 2008) or have assessed the impact of single threats, such as power lines (Lehman et al 2007) or wind farms (Drewitt & Langston 2006;Bernardino et al 2013). Assessing mortality causes is generally hard to pursue due to the difficulty in finding dead or dying wildlife and tracking animals until their death.…”