Isolation and characterization of polymorphic microsatellite loci in the Hawaiian flycatcher,the elepaio (Chasiempis sandwichensis)

Thirteen polymorphic microsatellite loci were isolated and characterized from two clades of an endemic Hawaiian flycatcher, the elepaio (Chasiempis sandwichensis). Seven dinucleotide repeats and one trinucleotide repeat were cloned from Kauai elepaio; five dinucleotide repeats were cloned from Oahu elepaio. Polymorphism was assessed in a sample of Oahu elepaio (n = 22) revealing two to 16 alleles per locus. Observed heterozygosity ranged from 0.14 to 0.91. However, linkage analysis exposed highly significant linkage disequilibrium between two of the most polymorphic loci. Twelve loci are therefore expected to be useful for investigations of population structure.     

Importance of Nest Predation by Alien Rodents and Avian Poxvirus in Conservation of Oahu Elepaio

ABSTRACT The Oahu elepaio (Chasiempis sandwichensis ibidis) is an endangered forest bird endemic to the Hawaiian island of Oahu (USA) and is threatened by nest predation from alien rodents and mosquito-borne diseases. I investigated importance of these threats and evaluated success of conservation efforts from 1995 to 2008. I controlled rodents with snap-traps and bait stations in 3 valleys and switched sites from non-treatment to treatment over time. I mist-netted and color-banded 91 elepaio, inspected them for symptoms of avian poxvirus (Poxvirus avium), and estimated survival using multistate mark-recapture models. I determined annual fecundity of each breeding pair and monitored success of 212 nests. The oldest known Oahu elepaio was ≥15 years old. Survival of females was higher with rodent control (0.82 ± 0.05) than without (0.55 ± 0.12), but survival of males was not affected by rodent control (0.86 ± 0.02 with vs. 0.84 ± 0.04 without). Survival of elepaio with active or inactive pox-like lesions was 4–10% lower than survival of elepaio with no pox symptoms. Rodent control resulted in higher annual fecundity (0.69 ± 0.05 vs. 0.33 ± 0.06 fledglings/pair) and nest success (62% vs. 33%). Female site-fidelity, mate fidelity, and female encounter probability were lower in the absence of rodent control because more females switched territories and mates after nest failure. Population growth calculated from survival and fecundity estimates was stable with rodent control (1.07 ± 0.04) but declining without rodent control (0.69 ± 0.05). Elepaio numbers have continued to decline despite rodent control, probably because some young birds disperse into adjacent unmanaged areas that act as sinks. The best immediate management strategy for Oahu elepaio is to conduct rodent control over larger areas. Restoration of native forest would benefit elepaio by providing nest sites that are less attractive to rodents. Construction of predator-proof fences and eradication of predators would provide the best long-term protection for elepaio.