1. Survival and abundance of short-finned pilot whales in the archipelago of Madeira, NE Atlantic.
- Author
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Alves, Filipe, Dinis, Ana, Nicolau, Cátia, Ribeiro, Cláudia, Kaufmann, Manfred, Fortuna, Caterina, and Freitas, Luís
- Subjects
GLOBICEPHALA ,MARINE mammals ,CETACEA - Abstract
Estimates of population parameters for the short-finned pilot whale, Globicephala macrorhynchus, are scarce in literature, contributing to an International Union for Conservation of Nature ( IUCN) status of Data Deficient. In this study, photo-identification data collected over 7 yr from Madeira were used to estimate for the first time survivorship, capture probability, and abundance in this species using mark-recapture methodology. The Cormack-Jolly-Seber model estimated that the adult island-associated ( i.e., resident and regular visitor) whales had a constant survival rate of 0.960 (95% CI: 0.853-0.990) and an annual capture probability varying between 0.372 ( CI: 0.178-0.619) and 0.843 ( CI: 0.619-0.947). A parameterization of the Jolly-Seber model estimated that 140 island-associated whales ( CI: 131-151) used the area throughout the course of the study. Based on a closed population model, the most precise (lower CV) annual estimate of the total number of pilot whales using the southern and eastern waters of Madeira (~900 km
2 ) in a 3 mo period covering summer/autumn was 334 animals ( CI: 260-437). No trend was observed. Despite including biases, the approach used in this study provided plausible estimates of population parameters, which can contribute to the regional conservation strategies. [ABSTRACT FROM AUTHOR]- Published
- 2015
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