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White-winged dove ( Zenaida asiatica L.) exposure to environmentally accessible lead is a management concern. Detectable concentrations of lead were found in 142 (66%) of 214 white-winged doves collected in 2002 and 2003 at two wildlife management units in South Texas. Mean ± SD lead concentration was 0.70 ± 1.10 μg/g dry weight and ranged from ND to 11.01 μg/g dw. Lead concentrations were significantly lower in the 2002 samples, but similar between management units, age, and gender. White-winged doves in South Texas are being exposed to lead in the environment with some reaching subclinical to toxic levels. [ABSTRACT FROM AUTHOR]

Our study determined if white-winged doves (WWDs; Zenaida asiatica asiatica) breeding in locations where environmentally persistent contaminants occur in the Lower Rio Grande Valley of Texas have levels of contaminants that can hinder reproduction. During summer 2003, 70 (32 males, 38 females) adult WWDs were collected from 8 at-risk sites. Liver tissues were analyzed for ten major and trace elements and muscle tissues were analyzed for 20 organochlorine compounds, 21 polychlorinated biphenyl congeners, and toxaphene. Samples were compared to ten (five male, five female) captive-raised control WWDs. Arsenic, chromium, and lead were not detected or were below the detection limit, whereas copper, zinc, selenium, mercury, nickel, cadmium, and silver were detected in 70 (100%), 70 (100%), 52 (74%), 21 (30%), 4 (6%), 1 (1%), and 1 (1%) WWDs, respectively. None of the detected elements had significant sampling site, bird gender, or Site × Gender interactions, and each occurred at background levels. Toxaphene and polychlorinated biphenyls were not detected, whereas DDE, dieldrin, γ-BHC, and chlordane were detected in 13 (19%), 5 (7%), 2 (3%), and 1 (1%) field-collected WWDs, respectively, but all concentrations occurred at background levels. Concentrations of elements and compounds in field-collected WWDs did not significantly differ from those of the controls. Correlations between leukocyte counts and detectable contaminants generally indicated no correlation between each percentage of leukocyte type present and levels of selenium, copper, zinc, mercury, or DDE detected. One sample that had 0.072 μg/g dieldrin exhibited a low lymphocyte percentage (66%) out of only five samples. Comparisons could not be made with γ-BHC, chlordane, or the other elements that had a low number of samples with detectable levels. Overall, concentrations of elements and organochlorines found in WWDs were below levels known to impair reproduction and survival in birds. [ABSTRACT FROM AUTHOR]

Previous studies have shown that determining sex of adult white-winged doves (Zenaida asiatica) by cloacal characteristics is highly reliable (90%), while using plumage characteristics and body weights are less so. The drawback of the cloacal technique is that the procedure requires use of a modified nasal speculum to probe the cloacal area, which could possibly cause injury to the bird. We hypothesized that females have a wider pelvis than males for the passage of eggs, which should be quantifiable, thereby providing a means of separating adult males and females. We measured pelvic spread (distance from tip to tip of pelvis) of adults (n = 249). Additionally, body masses were taken for a subset (n = 215) of the doves. Sex was positively determined by either cloacal examination of live birds or gonad examination of dead birds. Mean pelvic spread of males was significantly less than that of females. Whole body mass was not correlated with pelvic spread for either sex. Accuracy of the pelvic spread technique was 70%. We concluded that the resolution obtainable through determination of sex by pelvic spread in live adult white-winged doves was inadequate for the needs of most field researchers. [ABSTRACT FROM AUTHOR]