RT Journal Article
T1 Male‐Biased Adult Mortality in the Great Bustard Is Consistent With High Reproductive Costs and Aggravated by Anthropogenic Impact
A1 Alonso, Juan C.
A1 Martín, Beatriz
A1 Palacín, Carlos
A1 Martín De La Calle, Carlos Alfonso
A1 Alonso López, Javier Antonio
AB Sex differences in adult mortality have usually been explained as a result of differences between males and females in the costs associated with their reproductive investment. Investigating sex-biased mortality is important because it shapes mating opportunities, reproductive strategies and parental care. Here, using known fate models implemented in the RMark package, we estimate annual and monthly or seasonal adult survival rates in a sample of 339 great bustards (Otis tarda) radio-tagged in 1985–2013 and monitored up to 2020. We found that annual survival was lower in males than in females, and lower in Madrid, a highly anthropized region (males: 0.874, females: 0.931), than in Villafáfila, where very good habitat conditions still exist (males: 0.948, females: 0.973). The maximum ages reached by marked individuals were also higher in females (17.3 years) than in males (13.8 years). The seasonal survival pattern was similar in both sexes, with maximum mortality at the end of the mating and incubation period, and lower survival in males, suggesting a direct effect of reproductive cost in both sexes and a higher cost in males. These results are consistent with previous comparative studies, which attribute male-biased adult mortality to the cost of mating competition in males and egg productivity in females, although these hypotheses could not be tested in the present study. Anthropogenic mortality was considerable (39.5% of deaths) and also male-biased, with power line casualties standing out and affecting 3.5% of males and 1.9% of females each year in Madrid. Anthropogenic mortality thus contributes to aggravate the naturally biased survival rates and could be a major cause of the declines observed in most great bustard populations over the last decades.
PB John Wiley & Sons
SN 2045-7758
YR 2026
FD 2026-01-07
LK https://hdl.handle.net/20.500.14352/134822
UL https://hdl.handle.net/20.500.14352/134822
LA eng
NO Alonso, J. C., Martín, B., Palacín, C., Martín, C. A., & Alonso, J. A. (2026). Male-Biased Adult Mortality in the Great Bustard Is Consistent With High Reproductive Costs and Aggravated by Anthropogenic Impact. Ecology and Evolution, 16(1). https://doi.org/10.1002/ECE3.72713
NO This work was supported by Dirección General de Investigación of the Spanish Ministry of Science (projects PB91-0081, PB94-0068, PB97-1252, BOS2002-01543, CGL2005-04893/BOS, CGL2008-02567 and CGL2012-36345), Instituto Nacional para la Conservación de la Naturaleza and Dirección General de Conservación de la Biodiversidad, with contributions from HENARSA, FEPMA, the Dirección General de Medio Natural of Madrid Community, and the Junta de Castilla y León, and the Consejería de Medio Ambiente, Junta de Andalucía.
NO Ministerio de Ciencia, Innovación y Universidades (España)
NO Instituto Nacional para la Conservación de la Naturaleza (España)
NO Ministerio para la Transición Ecológica y el Reto Demográfico (España)
NO Henarsa
NO Fundación para la Ecología y la Protección del Medio Ambiente
NO Comunidad de Madrid
NO Junta de Castilla y León
NO Junta de Andalucía
DS Docta Complutense
RD 29 abr 2026