Prospecting decisions and habitat selection by a nocturnal burrow-nesting seabird

Introduced predators have caused declines and extirpations of many populations of insular avifauna, especially nocturnal burrow-nesting seabirds. The successful eradication of these introduced predators has resulted in recovery of some species but not others, the reasons why are not understood. The objectives of my study were to understand the recovery of seabird populations after the removal of an introduced predator by studying the processes underlying the formation of new colonies and the expansions of colonies after establishment. Specifically I asked: 1) how nocturnal seabird colony area and population size change with time and across a metapopulation; and 2) how prospectors choose suitable breeding habitat by looking at habitat selection and use of public information. Using an information theoretic approach I found 1) regional differences in both colony area and population density over time and between island groups; 2a) Ancient Murrelets breeding in Haida Gwaii exhibit a high degree of plasticity in their use of available breeding habitats and the amount of suitable habitat at Langara Island has not changed between 1981-2007; 2b) differences in colony attendance decisions between sites, but prospectors were not conclusively more risk averse than breeders; and 2c) Ancient Murrelet prospector activity increased during playback of conspecific vocalizations, but found no preference for burrows with olfactory and/or visual cues over those left empty. Overall, I conclude that although Ancient Murrelet life-history may prolong recovery times, both recovery and recolonization of restored breeding sites are plausible and using playbacks of conspecific vocalizations is an effective method to attract prospecting individuals to those sites.