Bird Use of Stormwater-Management Ponds: Decreasing Avian Attractants on Airports

Characteristics of stormwater-management ponds that contribute to avian hazards to aviation at airports have not been quantified. We selected 30 stormwater-management ponds (average 0.1 ha), approximately 50km from Seattle-Tacoma International Airport, as surrogates to on-airport facilities. We conducted 46 weeks of avian surveys (between 14 February 2005 and 17 February 2006) and evaluated model fit of 6 a priori models relative to pond use by an avian group via Kullback–Leibler information. Our full model, composed of pond surface area (sa), ratio of area of open water to area of emergent and woody vegetation (ow:ew), perimeter irregularity, and geographic isolation, was among 3 best approximating models for pond use by 9 of 13 groups (within Anatidae, Ardeidae, Charadriidae, Columbidae, Accipitridae, Laridae, and Rallidae) considered. The full model and models lacking sa or ow:ew were indistinguishable in fit for a group composed of avian species considered hazardous to aviation. For models selected, Akaike weights (i.e., relative likelihoods) ranged from 0.869 to 0.994. In contrast, relative likelihood for a mean model (i.e., a model including only an intercept) was \u3c10−4 for all groups. We suggest that designs of stormwater management ponds at airports in the Pacific Northwest should minimize the pond perimeter via circular or linear designs. Also, ponds should be located so as to reduce the number and proximity of other water resources within 1 km. For existing stormwater-management ponds at airports, we suggest reducing the availability of open water via covering or drawdown

It takes two: Evidence for reduced sexual conflict over parental care in a biparental canid

In biparental systems, sexual conflict over parental investment predicts that the parent providing care experiences greater reproductive costs. This inequality in parental contribution is reduced when offspring survival is dependent on biparental care. However, this idea has received little empirical attention. Here, we determined whether mothers and fathers differed in their contribution to care in a captive population of coyotes (Canis latrans). We performed parental care assays on 8 (n = 8 males, 8 females) mated pairs repeatedly over a 10-week period (i.e., 5–15 weeks of litter age) when pairs were first-time breeders (2011), and again as experienced breeders (2013). We quantified consistent individual variation (i.e., repeatability) in 8 care behaviors and examined within- and among-individual correlations to determine if behavioral plasticity within or parental personality across seasons varied by sex. Finally, we extracted hormone metabolites (i.e., cortisol and testosterone) from fecal samples collected during gestation to describe potential links between hormonal mechanisms and individual consistency in parental behaviors. Parents differed in which behaviors were repeatable: mothers demonstrated consistency in provisioning and pup-directed aggression, whereas fathers were consistent in pup checks. However, positive within-individual correlations for identical behaviors (e.g., maternal versus paternal play) suggested that the rate of change in all behaviors except provisioning was highly correlated between the sexes. Moreover, positive among-individual correlations among 50% of identical behaviors suggested that personality differences across parents were highly correlated. Lastly, negative among-individual correlations among pup-directed aggression, provisioning, and gestational testosterone in both sexes demonstrated potential links between preparental hormones and labile parental traits. We provide novel evidence that paternal contribution in a biparental species reaches near equivalent rates of their partners