Record Details
Field | Value |
---|---|
Title | Nest-site selection in cooperatively breeding Pohnpei Micronesian Kingfishers (Halcyon cinnamomina reichenbachii) : does nest-site abundance limit reproductive opportunities? |
Names |
Kesler, Dylan C.
(creator) Haig, Susan M. (advisor) |
Date Issued | 2002-03-12 (iso8601) |
Note | Graduation date: 2002 |
Abstract | Despite their inherent importance and utility as ecological examples, island species are among the most endangered and least studied groups. Guam Micronesian Kingfishers (Halcyon cinnamomina cinnamomina) exemplify the plight of insular biota as a critically endangered and understudied island bird that went extinct in the wild before they could be studied in their native habitat. Guam kingfishers currently exist only as a captive population in U.S. zoos. Using radio telemetry and visual observations of a wild subspecies of Micronesian Kingfisher (H. c. reichenbachii) from the island of Pohnpei, this study examined factors critical for the persistence of both the Guam and Pohnpei kingfishers. Behavioral observations indicated that the birds employ a cooperative social system, which included non-parent individuals that assisted in reproductive attempts of others. Because resource limitations have been cited as a potentially important factor in the evolution of cooperative behaviors and in conservation, this investigation assessed the characteristics and availability of a potentially limited nesting resource, arboreal termite nests. First, the characteristics of termite nests, or termitaria, selected by Micronesian Kingfishers for use as nest sites were modeled. Results suggested that Micronesian Kingfishers selected termitaria that were higher from the ground and larger in volume than unused termitaria. Further, there was little evidence that birds selected from among termitaria based on proximity to forest edges and foraging areas, placement on a tree, vegetation characteristics, or microclimate. Second, the number of termitaria with characteristics indicative of nest sites was assessed to determine if reproductive opportunities might be limited by the abundance of suitable termitaria. Results from this analysis suggested that although fewer termitaria existed with characteristics similar to those used for nesting, reproductive opportunities did not appear to be limited by their abundance. Therefore, while conservation strategies should be directed towards providing ample and appropriate nesting substrates, I found no evidence suggesting that termitaria abundance played a role in the evolution of cooperative breeding in Pohnpei Micronesian Kingfishers. Findings presented here will hopefully enhance our understanding of cooperative behaviors, as well as improve conservation efforts for Micronesian Kingfishers and other insular avifauna. |
Genre | Thesis/Dissertation |
Topic | Kingfishers -- Micronesia (Federated States) -- Pohnpei -- Reproduction |
Identifier | http://hdl.handle.net/1957/32284 |