Fine‐scale genetic structure reflects limited and coordinated dispersal in the colonial monk parakeet, Myiopsitta monachus

Abstract

The genetic structure of animal populations has considerable behavioural, ecological and evolutionary implications and may arise from various demographic traits. Here, we use observational field data and molecular genetics to determine the genetic structure of an invasive population of monk parakeets, Myiopsitta monachus, at a range of spatial scales, and investigate the demographic processes that generate the observed structure. Monk parakeets construct large nests that can house several pairs occupying separate chambers; these nests are often aggregated within nesting trees. We determined patterns of relatedness within compound nests, within nesting trees and between trees. Spatial autocorrelation analyses of pairwise genetic relatedness revealed fine‐scale genetic structure with relatives of both sexes spatially clustered within, but not beyond, nesting trees. In addition, males were more related to males sharing their compound nests than to other males occupying the same nesting tree. By contrast, males and females within compound nests were not significantly more closely related than elsewhere in the same tree, and we found no evidence for inbreeding. Adults showed high breeding site fidelity between years despite considerable disturbance of nest sites. Natal dispersal was female‐biased, but dispersal distances were relatively short with some natal philopatry observed in both sexes. Sibling coalitions, typically of males, were observed amongst both philopatric and dispersing birds. Our results show significant clustering of kin within compound nests and nesting trees resulting from limited and coordinated natal dispersal, with subsequent breeding site fidelity. The resulting genetic structure has implications for social behaviour in this unusual parrot species.

The Role of Monk Parakeets as Nest-Site Facilitators in Their Native and Invaded Areas

“…Unlike the other parrot species, monk parakeets build their own nests, a large structure of sticks located in trees or human construction such as pylons [14]. These nests normally include several chambers, each occupied by a different pair or kin groups that cooperate in the maintenance, breeding, and defense of the whole colony [14][15][16]. Monk parakeets usually tolerate the presence of other species in their nests, despite the fact that certain tenants may aggressively usurp active chambers [15].…”

Sex and Age Effects on Monk Parakeet Home-Range Variation in the Urban Habitat

“…This period of sampling was chosen because natal dispersal by juveniles in their first year, if present, has already taken place and the birds are ready to breed, building or maintaining nests, or actively breeding [30]. Monk parakeets are sedentary, long-lived, and use the nests year-round for roosting and breeding for multiple years [27,31]. The species is also colonial, building large compound nests [27].…”

“…Monk parakeets are sedentary, long-lived, and use the nests year-round for roosting and breeding for multiple years [27,31]. The species is also colonial, building large compound nests [27]. About 80% of birds breed in the same nest in successive years, and dispersing adult birds move an average distance of just 37 m [27], removing any bias of using two years.…”

“…The monk parakeet is a highly successful invasive species in Europe and North America [24,26]. The marking device has been successfully used to determine dispersal patterns of the species in an urban environment [27]. However, similar to other parrot species, no detailed data is currently available on its home-range size.…”

Advancing Genetic Methods in the Study of Parrot Biology and Conservation

“…In the Monk Parakeet, sexual monogamy was shown in their native and invasive sites [188], while a later study found evidence for extra pair paternity in their native range in Argentina and intra-brood parasitism at invasive sites [189]. A recent study on their breeding colonies showed fine-scale genetic structure, high breeding site fidelity, absence of inbreeding, and female-biased natal dispersal by genotyping individuals [190].…”