
Decreased selectivity during mate choice in a small‐sized population of a long‐lived seabird
Author(s) -
Bried Joël,
Andris Malvina,
Dubois MariePierre,
Jarne Philippe
Publication year - 2021
Publication title -
journal of avian biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.022
H-Index - 76
eISSN - 1600-048X
pISSN - 0908-8857
DOI - 10.1111/jav.02837
Subject(s) - biology , assortative mating , mating , population , seabird , ecology , zoology , effective population size , mate choice , population bottleneck , reproductive success , breeding pair , evolutionary biology , demography , predation , genetic variation , microsatellite , genetics , allele , sociology , gene
As biparental care is crucial for breeding success in Procellariiformes seabirds (i.e. albatrosses and petrels), these species are expected to be choosy during pair formation. However, the choice of partners is limited in small‐sized populations, which might lead to random pairing. In Procellariiformes, the consequences of such limitations for mating strategies have been examined in a single species. Here, we studied mate choice in another Procellariiforme, Bulwer's petrel Bulweria bulwerii , in the Azores (ca 70 breeding pairs), where the species has suffered a dramatic population decline. We based our approach on both a 11‐year demographic survey (capture–mark–recapture) and a genetic approach (microsatellites, n = 127 individuals). The genetic data suggest that this small population is not inbred and did not experience a genetic bottleneck. Moreover, pairing occurred randomly with respect to genetic relatedness, we detected no extrapair parentage (n = 35 offspring), and pair fecundity was unrelated to relatedness between partners. From our demographic survey, we detected no assortative mating with respect to body measurements and breeding experience and observed very few divorces, most of which were probably forced. This contrasts with the pattern previously observed in the much larger population from the Selvagens archipelago (assortative mating with respect to bill size and high divorce rate). We suggest that the Bulwer's petrels from the Azores pair with any available partner and retain it as long as possible despite the fact that reproductive performance did not improve with pair common experience, possibly to avoid skipping breeding years in case of divorce. We recommend determining whether decreased choosiness during mate choice also occurs in reduced populations of other Procellariiform species. This might have implications for the conservation of small threatened seabird populations.