DOI: 10.5061/dryad.905qfttsc
title: Data from: Lunar synchrony, geography, and individual clocks shape autumn migration timing in an avian migrant

description: Timing programs in animal migrants have been selected to synchronize
 movements that coincide with predictable resources on the breeding and
 nonbreeding grounds. Migrants face potential temporal conflicts if their
 migration schedules benefit from synchrony to conflicting rhythms
 associated with annual biogeographical (circannual) cues, lunar
 (circalunar) cues, or individually-repeatable internal clocks. We
 repeat-tracked individuals of an avian lunaphilic species, Eastern
 Whip-poor-will (Antrostomus vociferus), for 2–3 successive autumn
 migrations to determine the influence of the lunar cycle, breeding
 location, and individual repeatability on migration timing. Almost all
 birds avoided departing for migration during a full moon, likely to take
 advantage of the bright moonlight to facilitate visual foraging and
 enhance pre-migration fattening. However, groups from two
 latitudinally-distant sampling areas adjusted their autumn departure
 timing differently relative to the timing of the September full moon,
 presumably due to differences in seasonal prey availability. Individual
 repeatability increased throughout autumn migration, suggesting that the
 factors responsible for shaping migration timing may differ for different
 migration stages. Our results, that lunar synchrony, local climate, and
 individual internal clocks appeared to account for much of the variation
 in migration timing in whip-poor-wills, underscore the value of measuring
 potentially interacting factors that shape migratory behavior at species,
 group, and individual levels. It remains unclear if, or how, maintaining
 individually-repeatable annual migration schedules provides an adaptive
 benefit for whip-poor-wills or other lunaphilic migrants. Further
 clarifying the reasons for phenotypic variation in whip-poor-will
 migration timing will improve predictions of their abilities to adjust
 migratory movements under changing environmental conditions.
description: # Lunar synchrony, geography, and individual clocks shape autumn migration
 timing in an avian migrant 
 * all data are GPS locations and dates used for the investigation of the
 influence of full moon, sampling location, and individual repeatability on
 whip-poor-will autumn migration timing * all data are from adult male
 whip-poor-wills * data have been summarized from a more comprehensive GPS
 tracking dataset; these data have been filtered to include only the
 necessary data used in analyses * Antrostomus vociferus is currently
 listed as "Near-threatened" by the IUCN. Therefore, no GPS
 locations for exact breeding sites are included in the dataset. Locations
 in the departure dataset are for the first lat/lon recorded after each
 bird departed its breeding site * data contact: Alicia Korpach,
 **Data file: stopovers_EWPW.csv** -GPS
 locations for every stopover site from birds for which we had full
 migration tracks. -Includes dates and durations of stopover. -Only
 includes stopovers longer than one day in duration (i.e. locations where
 birds spent one full day between flight bouts). That is why some stopovers
 for each bird appear to be missing (i.e. some StopOrder values will be
 excluded). * IID: independent ID number * band_tag: individual birds’
 federal band number and GPS tag number * group: north or south sampling
 group * StopOrder: Stopover order from breeding to wintering sites. *
 n_points: GPS points collected at the stopover site * StopDuration_days:
 number of days bird spent at the stopover site * stopover_start: date of
 arrival to stopover site * stopover_end: date of departure from stopover
 site * lat: latitude * lon: longitude * Year: year data were collected
 **Data file: departures_EWPW.csv** dates of breeding site departures *
 IID: independent ID number * lat: latitude of first location after
 departing from the breeding site\ * lon: longitude of first location after
 departing from the breeding site * bandnum: individual birds’ federal band
 number * group: north or south sampling group * Repeat: whether this was
 not a repeat track (0), or a first (1) or second (2) repeat track * Year:
 year data were collected * depnight: date of departure night * ordinal:
 date in ordinal format * SeptFM: September full moon date in ordinal
 format **Data file: latcrossings_EWPW.csv** First GPS locations and dates
 after crossing various latitudes during southbound autumn migration * IID:
 independent ID number * lat: latitude of bird at first location after
 crossing the reference latitude * lon: longitude of bird at first location
 after crossing the reference longitude * bandnum: individual birds’
 federal band number * group: north or south sampling group * degrees:
 reference latitude * year: year data were collected * date: date of
 crossing reference latitude * ordinal: date in ordinal format **Data file:
 arrivals_EWPW.csv** GPS locations and dates of winter site arrivals * IID:
 independent ID number * lat: latitude * lon: longitude * bandnum:
 individual birds’ federal band number * group: north or south sampling
 group * Repeat: whether this was not a repeat track (0), or a first (1) or
 second (2) repeat track * Year: year data were collected * arrnight: date
 of arrival night * ordinal: date in ordinal format * SeptFM: September
 full moon date in ordinal format