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Copyright of Galapagos Research is the property of Charles Darwin Foundation for the Galapagos Islands and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We reconstructed a historical mourning dove Zenaida macroura nesting dataset to estimate nest survival and investigate the effect of covariates by using a Bayesian hierarchical model. During 1979-1980, 106 study areas, across 27 states, were established to conduct weekly nest searches during February-October. We used roughly 11,000 data sheets to reconstruct the dataset containing 7,139 nests compared to 6,950 nests in the original study. Original and reconstructed nest survival estimates showed little difference by using the original analysis methodology, that is, the Mayfield method. Thus, we assumed we closely replicated the original dataset; distributions of nests found, birds hatched, and birds fledged also showed similar trends. After confirming the validity of the reconstructed dataset, we evaluated 10 different models by using a Bayesian hierarchical modeling approach; the final model contained variables for nest age or stage, nest height, region, but not habitat. The year 1980 had a higher probability of nest survival compared to 1979, and nest survival increased with nest height. The nest encounter probability increased at days 4 and 11 of the nesting cycle, providing some insight into the convenience sampling used in the original study. Our reanalysis with the use of covariates confirms previous hypotheses that mourning doves are habitat generalists, but it adds new information showing lower nest survival during nest initiation and egg laying and a decline when fledglings would be 4 or 5 d old. Regional differences in mourning dove nest survival confirm existing hypotheses about northern states demonstrating greater nest success compared to southern states where differences may reflect trade-offs associated with northern latitudes, weather differences, or food availability. [ABSTRACT FROM AUTHOR]

A species of Eimeria new to science was discovered in fecal samples of mourning doves (Zenaida macroura) from Kentucky, U.S.A. Oocysts (n = 57) are spherical to ovoid, 24.2 μm ± 0.6 × 20.7 μm ± 0.4 (23-25.5 μm × 20-21.5 μm), with an average length/width (L/W) ratio of 1.2 (1.1-1.3). The oocyst wall is double layered, smooth, and colorless. The outer wall is 1 pm, and the inner wall is extremely thin. Oocyst residuum and micropyle are absent, but 0-2 variably shaped polar granules (PG) are present. Most PG are sausage shaped (1 × 1.5 μm), while others are round or globular (~0.8-1 μm). Among the 57 oocysts, 54 had 1 PG, 2 had two PG, and 1 oocyst lacked a detectable PG. Sporocysts (n = 83) are ovoid, 12.4 μm ± 0.5 × 7.3 μm ± 0.3 (12-13.8 μm × 6.9-8 μm), with an average LAV ratio of 1.7 (1.5--1.9). A knob-like Stieda body continuous with the sporocyst wall and a rounded substieda body are present. The sporocysts contained a sporocyst residuum made up of numerous granules of a uniform size (1 μm). Sporozoites are smooth with a terminal refractile body present. This is the third description of an Eimeria species from the genus Zenaida (Columbiformes: Columbidae) and the first report of Eimeria from the mourning dove. [ABSTRACT FROM AUTHOR]

The relative influence of genetic and phenotypic quality on pairing status and mating patterns in socially monogamous species remains poorly documented. We studied social status and pairing patterns in relation to genetic similarity and multilocus heterozygosity (MLH) estimates from 11 microsatellite markers, and both tarsus length and wing chord (as a measure of competitive ability in territorial defence) in a socially monogamous tropical bird species where individuals defend territories year-round, alone or in pairs, the Zenaida dove, Zenaida aurita. Tarsus length and wing chord did not differ between unpaired territorial birds and paired ones in either sex, whereas paired females, but not paired males, tended to be more heterozygous than unpaired ones. Among 84 pairs, we found no evidence for assortative mating for tarsus length, wing chord, MLH or genetic similarity. However, within pairs, male wing chord was positively related to female MLH and female tarsus length was positively related to male MLH, with no evidence for local effects, suggesting assortative mating by individual quality. Although the observed pattern of mating in Zenaida doves may be the product of mutual mate choice, further assessment of this hypothesis requires direct investigation of both mating preference in each sex and lifetime reproductive success in relation to body size and MLH. [ABSTRACT FROM AUTHOR]

Caribbean avifaunal biogeography has been mainly studied based on mitochondrial DNA. Here, we investigated both past and recent island differentiation and micro-evolutionary changes in the Zenaida Dove (Zenaida aurita) based on combined information from one mitochondrial (Cytochrome c Oxydase subunit I, COI) and 13 microsatellite markers and four morphological characters. This Caribbean endemic and abundant species has a large distribution, and two subspecies are supposed to occur: Z. a. zenaida in the Greater Antilles (GA) and Z. a. aurita in the Lesser Antilles (LA). Doves were sampled on two GA islands (Puerto Rico and the British Virgin Islands) and six LA islands (Saint Barthélemy, Guadeloupe, Les Saintes, Martinique, Saint Lucia and Barbados). Eleven COI haplotypes were observed that could be assembled in two distinct lineages, with six specific to GA, four to LA, the remaining one occurring in all islands. However, the level of divergence between those two lineages was too moderate to fully corroborate the existence of two subspecies. Colonisation of the studied islands appeared to be a recent process. However, both phenotypic and microsatellite data suggest that differentiation is already under way between all of them, partly associated with the existence of limited gene flow. No isolation by distance was observed. Differentiation for morphological traits was more pronounced than for neutral markers. These results suggest that despite recent colonisation, genetic drift and/or restricted gene flow are promoting differentiation for neutral markers. Variation in selective pressures between islands may explain the observed phenotypic differentiation. [ABSTRACT FROM AUTHOR]

Mourning dove ( Zenaida macroura) harvest management requires an assessment of birds shot and not recovered (hereafter, 'crippled doves') to fully determine harvest mortality. However, estimating crippling rates is challenging. We estimated mourning dove harvest mortality, which included crippling rates, on a public hunting area in Missouri, USA, by monitoring radiomarked doves. We also compared crippling rates of radiomarked doves with hunter-reported estimates of crippling. During 2005-2008, we estimated annual harvest mortality between 23% and 30% on the area. Crippling rates ranged from 18% to 50% of harvest mortality in radiomarked doves. In comparison, hunter-reported crippling rates during 2005-2011 (14-18%) were, on average, 30% lower but more consistent than estimates from radiomarked doves. During 2005-2008, harvest mortality of radiomarked doves was 27%, with one-quarter of this mortality coming from crippled doves. Our empirical results confirm previous reports that crippling is a sizeable component of dove harvest. The potential bias in hunter-reported crippling rates could result in overharvest if not considered. Therefore, future harvest management decisions should not overlook the potential impacts of crippling on populations, especially on locally managed public hunting areas. © 2013 The Wildlife Society. [ABSTRACT FROM AUTHOR]

Band recoveries provide requisite data for evaluating the spatial distribution of harvest relative to the distribution of breeding stocks for a wide variety of migratory species. We used direct and indirect band-recovery data to evaluate the distribution and derivation of harvest of white-winged doves ( Zenaida asiatica) banded before hunting season in 3 distinct strata in Texas, USA, during 2007-2010. We banded 60,742 white-winged doves during 2007-2010, and based on 2,458 harvest recoveries, the majority (>95%) of white-winged dove harvest occurred during the first 2 months of the hunting season (Sep-Oct). Juvenile white-winged doves represented a greater percentage of the direct recoveries than adults across all strata (north = 80%, central = 69%, south = 82%) and the majority of direct band recoveries (north = 75%, central = 90%, south = 78%) occurred within the original banding strata. Age-specific weighting factors and harvest derivation indicated that both juvenile and adult harvest were highest within the strata of original banding. Harvest distribution data corrected for band-reporting rates indicated high fidelity of white-winged doves to specific geographic strata, with little interplay between strata. Our results suggest that population vital-rate estimates for survival and harvest for use in future Adaptive Harvest Management should focus on stock-specific levels. © 2012 The Wildlife Society. [ABSTRACT FROM AUTHOR]

We quantified vigilance during feeding in the Zenaida Dove Zenaida aurita, a tropical species with stable pair-bonds and year-round territoriality. Both males and females decreased the proportion of time spent vigilant by 30% when feeding with their partner compared with when feeding alone. This reduction was achieved through increasing the length of inter-scan duration, while scan duration remained constant. No evidence was found for coordination of vigilance between pair members. The equal investment in vigilance by male and female Zenaida Doves might be related to the mutual benefits of long-term pair-bonding. [ABSTRACT FROM AUTHOR]

We report that an adult-sized Zenaida macroura (Mourning Dove), presumably a parent, rapidly decreased risk taken in defense of a juvenile as the likelihood of predation to the juvenile increased. We attribute this decrease in risk taken to (1) the parent's perception that the risk of predation had increased to the extent that a continuation of defensive behaviors would not prevent the death of the juvenile, and (2) its attempt to minimize its own risk of death. It may be that there is a threshold beyond which Mourning Dove parents will forgo the risk of additional defense of offspring in favor of making another reproductive attempt. [ABSTRACT FROM AUTHOR]

The article presents the results of the study on Zenaida Doves in Barbados to establish resource polymorphism or existence of alternative phenotypes in relation to resource use as a result of disruptive selection. It confirms that territorial adult doves were larger than flock-feeding ones and the reverse condition occurs among their juveniles. The article concludes that caution should be exerted when referring to well-defined ecological concepts such as resource polymorphism to interpret intrapopulation variation in foraging strategy.

Twenty-three polymorphic microsatellite loci, six dinucleotidic loci and 17 tetranucleotidic loci, were developed for the Zenaida dove (Zenaida aurita), a bird species endemic to the Caribbean Islands. From a set of 30 individuals captured at one single location in Barbados, we obtained 20 loci that did not deviate from Hardy-Weinberg Equilibrium. Number of alleles per locus ranged between 2 and 11 (average 7.05) and the expected heterozygosity per locus, He ranged between 0.321 and 0.881 (average 0.712). This gives an exclusionary power for parental analysis of 0.9999 and 1.0000, knowing the genotype of one social parent, or both, respectively. Such results indicate that these 20 loci will be useful for both studying population genetics and mate choice patterns in Z. aurita. All 20 loci amplified in four other Zenaida species, the Galápagos dove, Z. galapagoensis, the eared dove, Z. auriculata, the mourning dove, Z. macroura, the Pacific dove, Z. meloda, with 30-96% being polymorphic. [ABSTRACT FROM AUTHOR]

The core of eastern White-winged Dove (Zenaida asiatica asiatica) breeding habitat historically occurred in northern México and southern Texas. Much nesting-habitat loss has occurred in this region since the mid-1900s and several large nesting colonies of the historic complex have disappeared with others currently at risk. Little knowledge exists regarding the precise location of these colonies or their current status. We reviewed the literature, interviewed biologists, and conducted site visits to Tamaulipas, México during May-August 2004 and 2005 to construct a historical account of White-winged Dove colonies. We found references to 77 possible nesting colonies thought to exist over a 50-year period in Tamaulipas. However, 26 references represented alternative names for the same colonies resulting in 51 colonies. We located 31 of these colonies of which 13 were active and 18 were inactive. The remaining 20 were not described in sufficient detail to locate. Brush clearing was listed as a cause for 78% of the 18 inactive colonies followed by weather catastrophes (56%) and overharvest (39%). Collectively, these 3 factors appeared to be responsible for 94% of all colony loss. The historic, large colonies of the past are gone and likely will not return because of these factors, primarily because of brush clearing. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Entomologist is the property of Cambridge University Press and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Because the relationship between lead pellet availability and ingestion by mourning doves (Zenaida macroura) remains uncertain, we conducted an experiment to determine if doves held in captivity freely ingest lead shotgun pellets, investigate the relationship between pellet density and ingestion and monitor physiological impacts of doves ingesting pellets. We conducted two trials of the experiment with <60 doves per trial. We randomly assigned 10 doves to one of six groups per trial; 10, 25, 50, 100, 200 pellets mixed with food and a control group with no pellets. We monitored ingestion by examining x-rays of doves 1-d post-treatment and monitored the effects of lead ingestion by measuring heterophil:lymphocyte (H:L) ratios, packed-cell volume (PCV), blood lead, liver lead and kidney lead. Pooled data from both trials showed 6 of 117 (5.1%) doves ingested lead pellets. Two mourning doves ingested multiple lead pellets in each of the treatments containing a mixture of 25, 100 and 200 lead pellets and food. Doves ingesting lead pellets had higher blood lead levels than before treatment (P = 0.031). Post-treatment H:L ratios, however, were not different compared to pre-treatment values (P = 0.109). Although post-treatment PCV decreased for four of six doves ingesting lead pellets, overall they were not lower than their pre-treatment values (P = 0.344). Liver (P < 0.0001) and kidney (P = 0.0012) lead levels for doves ingesting pellets were higher than doves without ingested pellets. Our lead pellet ingestion rates were similar to previously reported ingestion rates from hunter-killed doves and our physiological measurements confirm earlier reports of a rapid and acute lead toxicosis. Similar to previous field research, we did not observe a relationship between pellet density in the food and ad libitum pellet ingestion. Although one approach would be to ban lead shot for mourning dove hunting on managed public hunting areas, further research is necessary to ensure that policy development and implementation have a consensus among stakeholders. [ABSTRACT FROM AUTHOR]

Mourning dove (Zenaida macroura) call-count surveys in Mississippi, USA, suggest declining populations. We used available mourning dove call-count data to evaluate long-term mourning dove habitat relationships. Dove routes were located in the Mississippi Alluvial Valley, Deep Loess Province, Mid Coastal Plain, and Hilly Coastal Plain physiographic provinces of Mississippi. We also included routes in the Blackbelt Prairie region of Mississippi and Alabama, USA. We characterized landscape structure and composition within 1.64-km buffers around 10 selected mourning dove call-count routes during 3 time periods. Habitat classes included agriculture, forest, urban, regeneration stands, wetland, and woodlot. We used Akaike's Information Criterion to select the best candidate model. We selected a model containing percent agriculture and edge density that contained approximately 40% of the total variability in the data set. Percent agriculture was positively correlated with relative dove abundance. Interestingly, we found a negative relationship between edge density and dove abundance. Researchers should conduct future research on dove nesting patterns in Mississippi and threshold levels of edge necessary to maximize dove density. During the last 20 years, Mississippi lost more than 800,000 ha of cropland while forest cover represented largely by pine (Pinus taeda) plantations increased by more than 364,000 ha. Our results suggest observed localized declines in mourning dove abundance in Mississippi may be related to the documented conversion of agricultural lands to pine plantations. [ABSTRACT FROM AUTHOR]

We respond here to a critique of our paper (Small et al. 2004b) regarding the methodology used to implant subcutaneous transmitters in white-winged doves (Zenaida asiatica). We agree with Mulcahy (2006) that more information regarding the methodology we used would have been appropriate. However, we refute the contention that we could not have followed the surgical protocol we cited and that protocols were not sterile. We believe this misinterpretation of our methods comes from a failure to note some of the finer points reported in our methodology. We address each issue made by Mulcahy (2006) in this response. [ABSTRACT FROM AUTHOR]

Island species, particularly endemics, tend to have lower genetic diversity than their continental counterparts. The low genetic variability of endemic species and small populations has a direct impact on the evolutionary potential of those organisms to cope with changing environments. We studied the genetic population structure and morphological differentiation among island populations of the Galapagos Dove (Zenaida galapagoensis). Doves were sampled from five islands: Santa Fe, Santiago. Genovesa, Española, and Santa Cruz. Five microsatellite markers were used to determine genetic diversity, population structure, gene flow, and effective population sizes. FST and RST values did not differ among populations; in general, populations with greater geographical separation were not more genetically distinct than those closer to one another, and estimated gene flow was high. There were no significant differences in allelic richness and gene diversity among populations. Although there was extensive morphological overlap among individuals from different island populations for both males and females, we found significant differences in overall body size only between populations on Santa Fe and Santa Cruz (males and females) and between Española and Santa Fe (males only). Significant differences in body size between populations undergoing high rates of gene flow indicate that differentiation may be due to either phenotypic plasticity or ecotypic differentiation. Based on the results of previously conducted disease surveys, we discuss the conservation implications for the Galapagos Dove and other endemics of the archipelago: we also discuss the possible effects of wind currents on gene flow. [ABSTRACT FROM AUTHOR]

It is critical to understand how radiotransmitters and their attachment techniques impact marked individuals. Many studies of transmitter effects assess only overt, deleterious effects. However, physiological effects caused by attachment techniques might compromise the integrity of resulting information. Our objectives, therefore, were to assess the efficacy of subcutaneous implants and determine the physiological effects on mourning doves (Zenaida macroura) using heterophil:lymphocyte (H:L) ratios, and fecal glucocorticoid measures. We conducted 2 trials with 60 mourning doves; 1 in summer-autumn (trial #1) and 1 in autumn-winter (trial #2). For each trial we assigned 1 5 male and 1 5 female doves to either a subcutaneous implant treatment or a control group. During the 2 trials, we observed no differences in body masses, H:L ratios or fecal corticosterone levels between mourning doves with subcutaneous implants and the control group. Given the ultimate use of the information obtained from telemetry projects and cost of the resulting initiatives, expenditures associated with rigorous experimental evaluations can only improve the basis of reliable knowledge used in making resource management decisions. [ABSTRACT FROM AUTHOR]

Despite the important place of resource polymorphisms in ecological and evolutionary theories, the reason why a group of individuals sharing a common environment should diverge in the use of the resources remains poorly known. Given the existence of distinct open niches and the relaxation of interspecific competition, niche theory suggests two possible mechanisms: resource competition between conspecifics and trade-offs in resource use efficiency. We investigated the importance of these explanations in a foraging polymorphism recently developed by Zenaida Doves (Zenaida aurita) on the West Indian island of Barbados. In this polymorphism, individuals either aggressively defend feeding territories from conspecifics or feed in large unaggressive groups with conspecifics. Combining field observations and a cage experiment, we found no evidence that the polymorphism is primarily driven by age- or sex-related differences, or that it results from morphological feeding specializations or dietary preferences. instead, our results support the hypothesis that individual specializations arise from contest competition. In the study area, competition for territories was intense, with very little undefended space left between territories and owners frequently involved in territorial contests. Replacement of territory holders from year to year was low compared to the number of potential recruits, implying that many doves were incapable of securing a territory. Approximately half the doves at territorial sites did not hold a territory but wandered between them as floaters. Compared with territory holders, floaters were smaller and had shorter wings, traits that in this species mediate territory defense. Yet floaters did not differ from group feeding doves on these morphological traits. This suggests that group feeders are floaters that shift to an alternative resource. The new resource appears to be suboptimal, as indicated by the fact that group feeders were in worse body condition than doves from the territorial sites. Taken together, our results suggest that the resource polymorphism in Zenaida Doves is primarily driven by competition for territories, which forces less competitive individuals to use alternative, subobtimal resources. [ABSTRACT FROM AUTHOR]

Few if any studies have examined the influence of a recently implemented hunting season on harvest characteristics of mourning doves (Zenaida macroura). We conducted a reward banding study in Ohio, USA, during 1996-1998 to compare harvest rates in urban and rural areas and to estimate overall harvest rate and band-reporting rate. Estimates from band-recovery models provided strong evidence for site- and year-specific variation in harvest rates of doves captured at urban and rural sites. Annual harvest-rate estimates ranged from 0.006 (95% CI: 0.001 to 0.011) to 0.011 (95% CI: 0.005 to 0.018) for birds captured at urban sites, and from 0.034 (95% CI: 0.022 to 0.045) to 0.054 (95% CI: 0.039 to 0.069) for birds captured at rural sites. The estimated reporting rate of 0.208 (95% CI: 0.142 to 0.274) was less than previously published estimates, probably because of a lack of familiarity of hunters with dove bands. In our study, >80% of the harvest of banded birds occurred in Ohio, suggesting that hunting pressure on this population is largely determined by Ohio hunters. Increased understanding of the role of urban landscapes as potential refuges from hunting pressure will improve our ability to manage dove harvests. Large-scale banding studies are needed to obtain contemporary estimates of harvest parameters, which are necessary for more informed harvest management of mourning doves. [ABSTRACT FROM AUTHOR]

Presents a study that investigated the demographic distribution of zenaida doves at Cayo Del Agua, Culebra, Puerto Rico. Background on zenaida doves; Analysis of annual changes in the density of ground nests; Assessment of the relation of rainfall to nest density and crab density.

The spatial and temporal clumping of food influence an animal's aggressiveness during competition. No studies, however, have investigated the effects of the temporal predictability of food and few studies have tested for interactions between the effects of two components of resource distribution on the rates of competitive aggression. We simultaneously manipulated the temporal predictability and the spatial clumping of food to test whether aggression increases as food becomes more predictable in time and more clumped in space. We tested these predictions using wild Zenaida doves (Zenaida aurita) in Barbados because previous work showed marked differences in social behavior between two populations, apparently related to differences in the distribution of food in space and time. There was a significant interaction between the effects of the temporal predictability and spatial clumping of food. As predicted, the rate of aggression increased as the temporal predictability of food increased, but only significantly in the spatially clumped condition. Similarly, as predicted, aggression increased as the spatial clumping of food increased, but only significantly in the temporally predictable condition. In addition, the per capita rate of aggression peaked at intermediate competitor densities in the spatially clumped condition. Differences in rates of aggression observed during experimental manipulations and between the two populations during baseline observations were generally consistent with predictions of resource defense theory. [ABSTRACT FROM AUTHOR]

Learning differences predicted from ecological variables can be confounded with differences in wariness of novel stimuli (neophobia). Previous work on feral pigeons (Columba livia), as well as on group-feeding and territorial zenaida doves (Zenaida aurita), reported individual and social learning differences predicted from social foraging mode. In the present study, we show that speed of learning a foraging task covaries with neophobia and latency to feed from a familiar dish in the three types of columbids. Pigeons were much faster than either territorial or group-feeding zenaida doves on all tests conducted in captivity, but showed unexpectedly strong neophobia in some urban flocks during field tests. Human proximity strongly affected performance in group-feeding doves both in the field and in captivity. They were slightly faster at learning than their territorial conspecifics in cage tests. In multiple regressions, species identity, but not social foraging mode, significantly predicted individual variation in learning, as did individual variation in neophobia. Wariness of novel stimuli and species differences associated with artificial selection appear to be more important than foraging mode and wariness of humans in accounting for learning differences between these columbids. [ABSTRACT FROM AUTHOR]

Deals with a study which reconstructed a phylogeny for the seven species of doves in the genus Zenaida on the basis of mitochondrial and nuclear DNA sequences. Methods; Results; Information on biogeography.

Presents a study which examined the demography of Zenaida Doves in three neighboring dairy farms in Puerto Rico during 1984 to 1997. Methodology; Results; Discussion.

Presents information on a study which estimated demographic parameters of Zenaida doves at farmlands and second-growth forests in eastcentral Puerto Rico during 1990-1992. Study area; Methods used; Results and discussion; Management implications.

Evaluates the accuracy of techniques used to assign age and gender to mourning dove in Missouri. Methods used; Probability of correctly classifying adult mourning doves; Assessment of age and gender for adult females and adult males; Error probabilities of observer ability to correctly assign age and gender.

Farmers in the Paranapanema Valley (São Paulo, Brazil) have reported problems with flocks of Eared Doves (Zenaida auriculata) eating sprouting soybeans. In this region these birds breed colonially in sugar-cane, and eat four crop seeds, using 70% of the dry weight, in the following order of importance: maize, wheat, rice, and soybeans. Three weeds (Euphorbia heterophylla, Brachiaria plantaginea, and Commelina benghalensis) were important. This information suggests that the doves adapted particularly well to the landscape created by the agricultural practices in the region, exploiting many available foods.

The article focuses on an analysis of nesting Zenaida macroura, commonly known as mourning dove in its entanglement in a fish line. It also discusses the dead mourning dove which hangs from a thread of monofilament fish line near its nest. It discusses the result of the bird's autopsy which reveals that the bird was on its healthy state, and probably egg laying have occurred within a day because of the near-calcified shell that was present in the oviduct.