Columbina Passerina Research Articles

Quantification of low levels of organochlorine pesticides using small volumes (≤100 μl) of plasma of wild birds through gas chromatography negative chemical ionization mass spectrometry

A solid phase extraction and gas chromatography with negative chemical ionization mass spectrometry in scan mode (GC-NCI-MS) method was developed to identify and quantify for the first time low levels of organochlorine pesticides (OCs) in plasma samples of less than 100 μl from wild birds. The method detection limits ranged from 0.012 to 0.102 pg/μl and the method reporting limit from 0.036 to 0.307 pg/μl for α, γ, β and δ-hexachlorocyclohexane (HCH), heptachlor, aldrin, heptachlor epoxide, endosulfan I, 1,1-dichloro-2,2-bis( p-chlorophenyl)ethylene ( p, p′-DDE), dieldrin, endrin, endosulfan-II, endrin-aldehyde and endosulfan-sulfate. Pesticide levels in small serum samples from individual Falco sparverius, Sturnella neglecta, Mimus polyglottos and Columbina passerina were quantified. Concentrations ranged from not detected (n/d) to 204.9 pg/μl for some OC pesticides. All levels in the food web in and around cultivated areas showed the presence of pesticides notwithstanding the small areas for agriculture existing in the desert of Baja California peninsula.

THE ROLE OF BODY SIZE IN HOST SPECIFICITY: RECIPROCAL TRANSFER EXPERIMENTS WITH FEATHER LICE

Abstract Although most parasites show at least some degree of host specificity, factors governing the evolution of specificity remain poorly understood. Many different groups of host-specific parasites show a striking correlation between parasite and host body size, suggesting that size reinforces specificity. We tested this hypothesis by measuring the relative fitness of host-specific feather lice transferred to pigeons and doves that differ in size by an order of magnitude. To test the general influence of size, we transferred unrelated groups of wing and body lice, which are specialized for different regions of the host. Lice were transferred in both directions, from a large native host species, the rock pigeon (Columba livia), to several progressively smaller hosts, and from a small native host species, the common ground dove (Columbina passerina), to several larger hosts. We measured the relative fitness (population size) of lice transferred to these novel host species after two louse generations. Neither wing lice nor body lice could survive on novel host species that were smaller in size than the native host. However, when host defense (preening behavior) was blocked, both groups survived and reproduced on all novel hosts tested. Thus, host defense interacted with host size to govern the ability of lice to establish on small hosts. Neither wing lice nor body lice could survive on larger hosts, even when preening was blocked. In summary, host size influenced the fitness of both types of feather lice, but through different mechanisms, depending on the direction of the transfer. Our results indicate that host switching is most likely between hosts of similar body size. This finding has important implications for studies of host-parasite coevolution at both the micro- and macroevolutionary scales.

Capture Stress and the Bactericidal Competence of Blood and Plasma in Five Species of Tropical Birds

In wild birds, relatively little is known about intra- or interspecific variation in immunological capabilities, and even less is known about the effects of stress on immune function. Immunological assays adaptable to field settings and suitable for a wide variety of taxa will prove most useful for addressing these issues. We describe a novel application of an in vitro technique that measures the intrinsic bacteria-killing abilities of blood. We assessed the capacities of whole blood and plasma from free-living individuals of five tropical bird species to kill a nonpathogenic strain of E. coli before and after the birds experienced an acute stress. Killing invasive bacteria is a fundamental immune function, and the bacteria-killing assay measures constitutive, innate immunity integrated across circulating cell and protein components. Killing ability varied significantly across species, with common ground doves exhibiting the lowest levels and blue-crowned motmots exhibiting the highest levels. Across species, plasma killed bacteria as effectively as whole blood, and higher concentrations of plasma killed significantly better. One hour of acute stress reduced killing ability by up to 40%. This assay is expected to be useful in evolutionary and ecological studies dealing with physiological and immunological differences in birds.

West Nile Virus Antibodies in Avian Species of Georgia, USA: 2000–2004

West Nile virus (WNV) was first isolated in the state of Georgia in the summer of 2001. As amplifying hosts of WNV, avian species play an important role in the distribution and epidemiology of the virus. The objective of this study was to identify avian species that are locally involved as potential amplifying hosts of WNV and can serve as indicators of WNV transmission over the physiographic and land use variation present in the southeastern United States. Avian serum samples (n=14,077) from 83 species of birds captured throughout Georgia during the summers of 2000-2004 were tested by a plaque reduction neutralization test for antibodies to WNV and St. Louis encephalitis virus. Over the 5-year period, WNV-neutralizing antibodies were detected in 869 (6.2%) samples. The WNV seroprevalence increased significantly throughout the study and was species dependent. The highest antibody prevalence rates were detected in rock pigeons (Columba livia), northern cardinals (Cardinalis cardinalis), common ground doves (Columbina passerina), grey catbirds (Deumetella carolinensis), and northern mockingbirds (Mimus polyglottos). Northern cardinals, in addition to having high geometric mean antibody titers and seroprevalence rates, were commonly found in all land use types and physiographic regions. Rock pigeons, common ground doves, grey catbirds, and northern mockingbirds, although also having high seroprevalence rates and high antibody titers against WNV, were more restricted in their distribution and therefore may be of more utility when attempting to assess exposure rates in specific habitat types. Of all species tested, northern cardinals represent the best potential avian indicator species for widespread serologic-based studies of WNV throughout Georgia due to their extensive range, ease of capture, and high antibody rates and titers. Due to the large geographic area covered by this species, their utility as a WNV sentinel species may include most of the eastern United States.

THE ROLE OF BODY SIZE IN HOST SPECIFICITY: RECIPROCAL TRANSFER EXPERIMENTS WITH FEATHER LICE

Although most parasites show at least some degree of host specificity, factors governing the evolution of specificity remain poorly understood. Many different groups of host-specific parasites show a striking correlation between parasite and host body size, suggesting that size reinforces specificity. We tested this hypothesis by measuring the relative fitness of host-specific feather lice transferred to pigeons and doves that differ in size by an order of magnitude. To test the general influence of size, we transferred unrelated groups of wing and body lice, which are specialized for different regions of the host. Lice were transferred in both directions, from a large native host species, the rock pigeon (Columba livia), to several progressively smaller hosts, and from a small native host species, the common ground dove (Columbina passerina), to several larger hosts. We measured the relative fitness (population size) of lice transferred to these novel host species after two louse generations. Neither wing lice nor body lice could survive on novel host species that were smaller in size than the native host. However, when host defense (preening behavior) was blocked, both groups survived and reproduced on all novel hosts tested. Thus, host defense interacted with host size to govern the ability of lice to establish on small hosts. Neither wing lice nor body lice could survive on larger hosts, even when preening was blocked. In summary, host size influenced the fitness of both types of feather lice, but through different mechanisms, depending on the direction of the transfer. Our results indicate that host switching is most likely between hosts of similar body size. This finding has important implications for studies of host-parasite coevolution at both the micro- and macroevolutionary scales.

West Nile Virus Epizootiology in the Southeastern United States, 2001

We investigated mosquito and bird involvement in West Nile virus (WNV) transmission in July 2001 in Jefferson County, FL, and Lowndes County, GA. We detected 16 WNV-infected pools from Culex quinquefasciatus, Cx. salinarius, Cx. nigripalpus, and Culiseta melanura. In Florida, 11% of 353 bird sera neutralized WNV. Antibody prevalence was greatest in northern cardinal (Cardinalis cardinalis, 75%), northern mockingbird (Mimus polyglottus, 50%), common ground-dove (Columbina passerina, 25%), common grackle (Quiscalus quiscula, 15%), domestic chicken (Gallus gallus, 16%), and house sparrow (Passer domesticus, 11%). Antibody-positive birds were detected in nine of 11 locations, among which prevalence in chickens ranged from 0% to 100%. Seropositive chickens were detected in Georgia as well. The primary transmission cycle of WNV in the southeastern United States apparently involves Culex mosquitoes and passerine birds. Chickens are frequently infected and may serve as effective sentinels in this region.

Results and evaluation of the first study of organochlorine contaminants (PCDDs, PCDFs, PCBs and DDTs), heavy metals and metalloids in birds from Baja California, México

Organochlorine compounds (OCs) including polychlorinated dibenzo- p-dioxins (PCDDs), dibenzofurans (PCDFs), polychlorinated biphenyls (PCBs) and 1,1-dichloro-2,2-bis( p-chlorophenyl)ethylene ( p- p′-DDE), heavy metals (Pb, Cd, Zn, Cu), and arsenic were measured in house sparrows ( Passer domesticus) and common ground doves ( Columbina passerina) from Baja California Sur, México. Concentrations of PCDD/Fs were low, with 21 pg/g for house sparrows, and 7.7 pg/g for common ground doves. Non- ortho-PCB concentrations in house sparrow and common ground doves were 58 and 254 pg/g, respectively, and are within the highest concentrations reported in species that are in the low levels of food webs. The major differences in organochlorine levels between species were found for ortho-PCBs and DDTs. ortho-PCB levels were higher in the seedeater species, whereas DDT levels were higher in the omnivorous species. Heavy metal levels were far below those associated with negative effects.

Problem solving and neophobia in a columbiform–passeriform assemblage in Barbados

Previous research suggests a link between innovation rate, neophobia and behavioural flexibility in the field and in captivity. In this paper we examine three correlates of flexibility in five opportunistic avian species that feed together in Barbados: three Passeriformes (the Carib grackle, Quiscalus lugubris, the Lesser Antillean bullfinch,Loxigilla noctis , and the shiny cowbird, Molothrus bonariensis) and two Columbiformes (the zenaida dove,Zenaida aurita and the common ground dove, Columbina passerina). The flexibility measures are habituation to a new food patch, willingness to feed near a novel object (neophobia) and ability to obtain food from a new apparatus (problem solving). Passeriformes (in particular grackles and bullfinches), as predicted from their high innovation rate in anecdotal data, outperformed Columbiformes on all three measures. The three tests yielded similar results in the field and in captivity. Grackles, which are members of the most innovative passeriform genus in North America after Corvus, were by far the most successful species on the problem solving test. Individual variation in attempts to obtain food from the new apparatus was predicted by latency to approach it, which was in turn predicted by latency to feed near novel objects. This study provides experimental evidence, both in the field and in captivity, for the taxonomic differences in innovative flexibility seen in anecdotal data and suggests that neophobia is an important intervening variable in response to new feeding problems.

Patterns of avian seroprevalence to western equine encephalomyelitis and Saint Louis encephalitis viruses in California, USA.

Temporal and spatial changes in the enzootic activity of western equine encephalomyelitis (WEE) and St. Louis encephalitis (SLE) viruses were monitored at representative wetland study sites in the Coachella, San Joaquin, and Sacramento valleys of California from 1996 to 1998 using three methods: (1) virus isolation from pools of 50 host-seeking Culex tarsalis Coquillett females, (2) seroconversions in flocks of 10 sentinel chickens, and (3) seroprevalence in wild birds collected by mist nets and grain baited traps. Overall, 74 WEE and one SLE isolates were obtained from 222,455 Cx. tarsalis females tested in 4,988 pools. In addition, 133 and 40 seroconversions were detected in 28 chicken flocks, and 143 and 27 of 20,192 sera tested from 149 species of wild birds were positive for antibodies to WEE and SLE, respectively. WEE was active in all three valleys, whereas SLE only was detected in Coachella Valley. Seroconversions in sentinel chickens provided the most sensitive indication of enzootic activity and were correlated with seroprevalence rates in wild birds. Avian seroprevalence rates did not provide an early warning of pending enzootic activity in chickens, because positive sera from after hatching year birds collected during spring most probably were the result of infections acquired during the previous season. Few seroconversions were detected among banded recaptured birds collected during spring and early summer. Age and resident status, but not sex, were significant risk factors for wild bird infection, with the highest seroprevalence rates among after hatching year individuals of permanent resident species. Migrants (with the exception of mourning doves) and winter resident species rarely were positive. House finches, house sparrows, Gambel's quail, California quail, common ground doves, and mourning doves were most frequently positive for antibodies. The initial detection of enzootic activity each summer coincided closely with the appearance of hatching year birds of these species in our study areas, perhaps indicating their role in virus amplification. Bird species most frequently positive roosted or nested in elevated upland vegetation, sites where Cx. tarsalis host-seeking females hunt most frequently. These serosurveys provided important background information for planned host competence and chronic infection studies.

Louse flies on birds of Baja California.

Louse flies were collected from 401 birds of 32 species captured in autumn of 1996 in Baja California Sur (Mexico). Only one louse fly species (Microlynchia pusilla) was found. It occurred in four of the 164 common ground doves (Columbina passerina) collected. This is a new a host species for this louse fly.

Distribution and Relative Abundance Patterns of Columbids in Puerto Rico

From July 1986 to January 1989 standardized call and sight counts were conducted to examine the distribution and relative abundance patterns of Plain Pigeons (Columba inornata), White-crowned Pigeons (C. leucocephala), Scaly-naped Pigeons (C. squamosa), Zenaida Doves (Zenaida aurita), White-winged Doves (Z. asiatica), Mourning Doves (Z. macroura), Common Ground-Doves (Columbina passerina), Ruddy Quail-Doves (Geotrygon montana), Key West Quail-Doves (G. chrysia), and Bridled Quail-Doves (G. mystacea) during the different seasons of the year in the dry, moist and wet zones of Puerto Rico. The relative abundance of all columbids peaked during the spring-summer period (March-August) in the life zones. The relative abundance of Zenaida Doves and Common Ground-Doves peaked during the spring-summer, but a second noticeable peak occurred during the fall (September-November) in the dry zone. The seasonal patterns of relative abundance were detectable at local as well as at regional scales of sampling, regardless of the observer involved and the counting technique applied. The detected patterns are not considered to be either the result of sampling error or of statistical artifacts. The seasonal patterns of relative abundance in the three major life zones probably represent the most general and repeatable aspect of the population dynamics of columbids in the island. Two components of the environment of columbids are considered of principal importance in determining their seasonal relative abundance in the life zones: (1) rainfall in the dry zone, and (2) fruiting phenology of key tree species in the moist and wet zones.

Hosts and population dynamics of Amblyomma variegatum (Acari: Ixodidae) on Guadeloupe, French West Indies.

The hosts used and the importance of each host in the population dynamics of Amblyomma variegatum (F.) (the tropical bont tick) on Guadeloupe are presented. All potential hosts of the tick were sampled in three habitat types (defined by rainfall and topography) used for livestock production. Over 99% of all host-associated ticks were on cattle, goats, feral dogs, and mongooses. Other hosts of immature ticks were free-ranging domestic chickens, cattle egrets, Carib grackles, common ground doves, and grassquits. Adult ticks were collected only on cattle and goats, the most important hosts for all stages of A. variegatum . Cattle, mongooses, and Carib grackles were the most abundant host species found in each of the three habitat types; dry pasture habitat (lower rainfall and not seasonally flooded) supported the highest densities of ticks on these hosts. Potential methods of dissemination of A. variegatum to uninfested areas are discussed. Incidental collections of other tick species are given.

An avian survey of a coastal scrub area, St. Kitts, West Indies

The resident avifauna of a coastal scrub community on St. Kitts, West Indies, was surveyed in 1982 in order to examine what factors may be influencing its composition. Fifteen species were observed, three of which (Dendroica petechia, Tiaris bicolor and Columbina passerina) accounted for over 61% of the total observations. The results are briefly discussed in light of some current theories on avian community structure.