10.5061/DRYAD.XWDBRV1CK
Bartlow, Andrew
0000-0002-1254-4481
Los Alamos National Laboratory
Jankowski, Mark
Environmental Protection Agency
Hathcock, Charles
Los Alamos National Laboratory
Ryti, Randall
Neptune and Company, Inc.
Reneau, Steven
Los Alamos National Laboratory
Fair, Jeanne
Los Alamos National Laboratory
Data from: Sex ratio of Western Bluebirds Sialia mexicana is mediated by
phenology and clutch size
Dryad
dataset
2021
2021-01-15T00:00:00Z
2021-01-15T00:00:00Z
en
154819 bytes
4
CC0 1.0 Universal (CC0 1.0) Public Domain Dedication
Mothers may produce more of one sex to maximize their fitness if there are
differences in the cost of producing each sex or there are differences in
their relative reproductive value. We tested if breeding date, clutch size
and drought conditions influenced offspring sex ratios in Western
Bluebirds (Sialia mexicana) from 1997 to 2017. We found that hatch
dates late in the breeding season were associated with the production of
more females. When clutch size was taken into account, small clutches
yielded significantly more females late in the breeding season compared to
the early and middle parts of the breeding season that produced
significantly more males. Large clutches early in the season tended to
produce more females, although this was not significant. Drought severity
was not correlated with sex ratio adjustment.
Sex_Ratio_WEBLs.csv: Sex ratios of individual Western Bluebird nestlings
from 1997 to 2017. Columns: Year: Year data was collected Nestling ID:
Individual identification number of each nestling Nest Box: Nest box in
which nestlings were raised Elevation (ft): Elevation of the nest box in
feet Brood Clutch Size: Size of the brood within a nest box Hatch Date:
Julian date that the first egg hatched in a brood Sex: Sex of each
nestling (1 = male, 0 = female) Watershed: Watershed where each box was
located Canyon: Canyon where each box was located