DOI: 10.5061/dryad.612jm647x
title: Data and analysis code for Norton and DuVal - Causes and consequences of nest site fidelity in a tropical lekking bird: win-stay-lose-shift tactics are unrelated to subsequent success, but site-faithful females nest earlier

description: Nest site selection influences the survival of care-giving parents and
 their offspring, but search costs and site availability may limit site
 choices. Returning to previous nest sites may reduce costs and allow
 parents to better avoid local predators or access familiar resources. We
 investigated nest site fidelity in the Lance-tailed Manakin (Chiroxiphia
 lanceolata), in which long-lived females raise offspring without male
 assistance, and found that site choices are responsive to past success but
 do not predict future outcomes. We compared georeferenced nest locations
 for the same females detected in consecutive years (245 comparisons for
 138 females) and females nesting repeatedly within a year (137 comparisons
 for 97 females). Females were faithful to nesting sites in 13.9% of
 comparisons across years and 10.2% within years, and were more likely to
 nest again in the same site if their offspring fledged. When switching
 sites, females moved farther if their previous nest failed. Nest-site
 fidelity was unrelated to mate fidelity or female age. We then assessed
 whether site choice related to subsequent female survival, nest timing, or
 nest survival. Contrary to the hypothesis that win-stay-lose-shift tactics
 improve subsequent nesting outcomes, we found females were no more likely
 to fledge chicks or survive to a later year after they reused nest-sites.
 However, across years, site-faithful females nested earlier on average
 than females that switched sites. Early nests were more likely to fledge
 chicks, and early-nesting females were more likely to renest when their
 first nesting effort was complete. Win-stay-lose-shift tactics may allow
 females to avoid areas where predation is likely, but new nest sites are
 not safer. Females that reuse nest sites benefit from early nest
 initiation, which both correlates with immediate success and creates
 potential for longer-term benefits of fidelity through increased
 opportunities to renest throughout the breeding season.
description: We used 19 years of information on the nest locations of
 individually banded female Lance-tailed Manakins to investigate why
 females renest at the same sites, and whether this behavior improves
 female survival or fledging success of the subsequent offspring.
 Lance-tailed Manakin females often have multiple nests in a single field
 season. Therefore, we examined effects of site-fidelity across years as
 well as within a year. When comparing a female’s nests across years, the
 most temporally adjacent nests were compared (e.g., a female’s final nest
 in 2010 was compared to her first nest in 2011). For nests in the same
 year, we used the lay date to determine which nest was active
 first. Field methods: Nests were located by visual
 inspection of understory vegetation whenever a research team was present
 at the field site (usually March – early June annually). Nests were
 monitored every 2-4 days to determine dates of laying and hatching, as
 well as whether offspring successfully fledged. Fledging usually occurred
 around 16 days after hatching, and chicks that disappeared from the nest
 after 15 days with no signs of depredation were assumed to have fledged.
 Maternal identity was determined from the unique color band combination of
 females attending the nest, either by observation from a blind placed
 &gt;10m from the nest, or by video recording. When females were
 unbanded, they were captured with mistnets at the nest and individually
 marked, as above. After offspring fledged or nest contents disappeared
 (and were presumed to be depredated), researchers recorded nest location
 with a GPS point (Garmin eTrex models, &lt;6m accuracy). When lay date
 was not directly observed, it was inferred from hatch date by assuming an
 incubation period of 18 days. Starting in 2010, one egg of each two-egg
 nest was artificially incubated to ensure a genetic sample (Jones and
 DuVal 2019), and so lay date could also be inferred from embryo
 developmental stage in later years of data.  Distances
 between nests were estimated in meters, by applying the Pythagorean
 Theorem to nest pairs, with nest coordinates measured in UTMs. Nest-site
 choice was categorized as “faithful” if females moved less than 12 meters
 between consecutive nests. We chose the cutoff distance of 12 meters
 because distances were calculated from GPS locations with accuracy
 &lt;6m. If the locations of two consecutive nests were recorded with
 maximal and opposite error, they could appear to be 12 meters apart when
 they were actually in the same sapling. Therefore, when nests were at
 least 12 meters apart, we were confident that the female was nesting in a
 new location. In practice, many instances of site fidelity occurred on a
 finer scale; researchers returning to search for nests in multiple years
 often noted that a specific nesting fork was reused, and such observations
 served as the initial inspiration for this analysis.