Survival, Movements, and Breeding of Released Hawaiian Geese: An Assessment of the Reintroduction Program

Abstract

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Nest-Habitat Selection by the Phainopepla: Congruence Across Spatial Scales But Not Habitat Types

“…However, the availability of water during molt may provide opportunity for N n to escape predators. These findings may not apply to other subpopulations, whose patterns of diel and seasonal movement notably different (see Black et al 1997, Woog 1999.…”

“…We predicted differences in preference for both habitat type and elevation between the breeding and nonbreeding seasons at the meso scale. We expected habitat preferences to shift seasonally, as found by Black et al (1997) and Woog (1999), who demonstrated that N n prefer short, exotic grasses for nonbreeding-season foraging and native desert shrubland for nesting and molting. We investigated whether during molt N n prefer locations near water, as observed among other species of geese (Madsen and Mortensen 1987, Kahlert 2003, Radtke and Dieter 2010.…”

“…Restriction to remote locations was caused by hunting, habitat loss, and predation by non-native mammals (Baldwin 1945, Banko et al 1999. Black et al (1997) found that N n that remained at upper elevations year round experienced reduced productivity and higher mortality than those that dispersed from release sites. Black et al (1994) argued that pastures were essential for population recovery, and during breeding and molt we documented preference for such grasslands when available.…”

“…Although breeding success remains low and predation high, decades of captive propagation and releases into the wild have resulted in a population of approximately 2000 N n statewide, which is not yet self-sustaining (USDI 2004). N n have reestablished some patterns of seasonal movement across Hawai'i Island similar to those documented by early naturalists (Hess 2011), but more sedentary segments of the population face increased mortality from dehydration and starvation (Black et al 1997). Much is known of the species' habitat selection during the breeding season, but all published information is from subpopulations that move little seasonally (Banko et al 1999).…”

“…The proportion of available cover classes varied according to site (Table 1). We randomly selected ten daytime and ten nighttime locations used by each subject per study site, and, using Hawth's Tools, randomly generated ten plot locations in each cover class per study site below 3000 m, the species' maximum documented elevation (Black et al 1997, Hess 2011. We used all available GPS coordinates from sites where 10 random GPS coordinates were not available.…”