Genetic diversity and population structure of two endangered neotropical parrots inform In Situ and Ex Situ conservation strategies

A key aspect in the conservation of endangered populations is
understanding patterns of genetic variation and structure, which can
provide managers with critical information to support evidence-based
status assessments and management strategies. This is especially important
for species with small wild and larger captive populations, as found in
many endangered parrots. We used genotypic data to assess genetic
variation and structure in wild and captive populations of two endangered
parrots, the blue-throated macaw, Ara glaucogularis, of Bolivia, and the
thick-billed parrot, Rhynchopsitta pachyrhyncha, of Mexico. In the
blue-throated macaw, we found evidence of weak genetic differentiation
between wild northern and southern subpopulations, and between wild and
captive populations. In the thick-billed parrot we found no signal of
differentiation between the Madera and Tutuaca breeding colonies or
between wild and captive populations. Similar levels of genetic diversity
were detected in the wild and captive populations of both species, with
private alleles detected in captivity in both, and in the wild in the
thick-billed parrot. We found genetic signatures of a bottleneck in the
northern blue-throated macaw subpopulation, but no such signal was
identified in any other subpopulation of either species. Our results
suggest both species could potentially benefit from reintroduction of
genetic variation found in captivity, and emphasize the need for genetic
management of captive populations.