15 research outputs found

    BREEDING PERFORMANCE IN RELATION TO NEST-SITE SUBSTRATUM IN A BUFF-NECKED IBIS (THHWTICUS CA UDATUS) POPULATION IN PATAGONIA'

    Get PDF
    Abstract. In northern Argentinean Patagonia, Buff-necked Ibis (Theristicus caudatus) nest on different substrata: cliffs, trees, and marsh vegetation. According to the ideal-free distribution hypothesis, this polymorphism may be due to the occupation ofthe best breeding habitats by dominant individuals and the relegation of the subdominant birds to marginal substrata with a lower probability of achieving successful breeding. We investigated whether there were any variations in the breeding performance among colonies and whether these variations were related to the breeding substratum. Laying date varied from the third week of September to the last week of October, laying occurring earlier in colonies at lower elevations. Clutch size per colony varied between 1.8 and 2.0 (X 1.9, n = 106), but significant differences were not detected among colonies. Brood size per colony varied significantly, ranging between 1.3 and 2.0 (52 = 1.8, n = 164). The substratum of breeding did not influence variations in any of these three parameters. The physical condition of the chicks did not vary among substrata, but there was inter-colony variation in broods of two chicks. Daily rates of nest losses were similar among colonies reaching 6.2% (n = 856) during incubation and 1.4% (n = 966) during the nestling period. Brood reduction was low; the daily mortality rate of chicks (0.7%, n = 934) did not vary among colonies. The most common known cause of nest and chick losses was predation. These results indicate that breeding success varied only slightly from one colony to the other and that these variations are independent of the nesting substratum. In consequence, birds would not prefer one substratum over another

    Presumed killers? Vultures, stakeholders, misperceptions, and fake news

    Get PDF
    Vultures and condors are among the most threatened avian species in the world due to the impacts of human activities. Negative perceptions can contribute to these threats as some vulture species have been historically blamed for killing livestock. This perception of conflict has increased in recent years, associated with a viral spread of partial and biased information through social media and despite limited empirical support for these assertions. Here, we highlight that magnifying infrequent events of livestock being injured by vultures through publically shared videos or biased news items negatively impact efforts to conserve threatened populations of avian scavengers. We encourage environmental agencies, researchers, and practitioners to evaluate the reliability, frequency, and context of reports of vulture predation, weighing those results against the diverse and valuable contributions of vultures to environmental health and human well-being. We also encourage the development of awareness campaigns and improved livestock management practices, including commonly available nonlethal deterrence strategies, if needed. These actions are urgently required to allow the development of a more effective conservation strategy for vultures worldwide.Peer reviewe

    European vultures' altered behaviour

    No full text
    Correspondence.Peer Reviewe
    corecore