Estimating genetic diversity of Palila (Loxioides bailleui) and familial relationships of helper males

Author:

Patch-Highfill, Leayne D.

Title:

Estimating genetic diversity of Palila (Loxioides bailleui) and familial relationships of helper males

Periodical:

Tropical conservation biology and environmental science

Year:

2008

Volume:

M.S.

Pages:

92

Subject:

Palila Loxioides bailleui Loxops virens Birds Mauna Kea Birds conservation

Summary:

The critically endangered Palila (Loxioides bailleui) found only on Mauna Kea, Hawaii is one of the last surviving “finch-billed” Hawaiian honeycreepers, and currently the most actively studied forest bird in Hawaii. Due to habitat loss, predation by nonendemic mammals, and introduced avian disease, Palila occupy a fraction of their historical range. Recent population surveys report that population estimates have drastically decreased and if the current trend continues, Palila could be extinct in the next ten years. Estimating the level of genetic diversity within the Palila population could give researchers insight as to how likely Palila can adapt to their changing environment. In this study, a modified Amplified Fragment Length Polymorphism (AFLP) protocol was used to generate 312 polymorphic loci in 172 Palila. One-hundred ten adult Palila were examined to detect overall genetic diversity within the population. Results suggest that observed heterozygosity is estimated at 0.220 (Bayesian, Hickory v. 1.0.4), which appears comparable to other finch species. Additional Palila males (helpers) have been observed at nests of presumed monogamous pairs helping feed incubating females and offspring. Using 25 complete (n=96) and six incomplete families (n=20), the familial relationship of the helper male was determined. Relatedness tests based on exclusion and similarity coefficients (Bionumerics v. 2.0) suggest that the helper males appear more related to the offspring than to presumed unrelated adults in the population. Estimating the relatedness of helper males may help determine whether Palila are developing cooperative breeding as a strategy to better their chances of survival in a changing environment.

Date:

July 2008

Collection:

Monographs