Urban living influences the nesting success of Darwin’s finches in the Galápagos Islands

1) We examined whether location (urban=PB and non-urban=OG) affected the binary presence or absence of nests with eggs, nests with nestlings, and trash in nest material. We examined the effect of location on hatching and nestling survival trials, where the response variable is a matrix of trials, which are successes and failures, where the number of eggs hatched and nestling fledged per nest represent successes while eggs not hatched and nestling mortalities represent failures, respectively. We also used examined the effect of location along with the proportion of anthropogenic debris in the nest on nestling survival, where nest survival was measured as successes and failures.<br>2) Examined nest survival data over the incubation and nestling periods. Nest fates (binary success=1 or failure=0) over the number of exposure days where each exposure day (obsdays) is a trial. The explanatory variables are covariates of location (urban= PB and non-urban=OG) and proportion of anthropogenic debris in nests which are also weighted by the number of exposure days. Exposure days (obsdays) were calculated using the median of the last day the nest was known active to the last check day when the nest outcome or fate was known. <br>3) Calculated total person-hours by multiplying the number of hours searched by the number of people searching for each day at both sites (urban and non-urban respectively) across all days of the survey period. We tested survey effort using an independent t-test on total person-hours per day at each site.<br>4) Reproductive activity of nests with eggs, nestlings, and fledgling (where fledging occurred that week) across each week of the study period in non-urban (OG) and urban (PB) sampling areas.