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Estimating the Effects of Habitat and Biological Interactions in an Avian Community.

Dorazio RM, Connor EF, Askins RA - PLoS ONE (2015)

Bottom Line: Our results also suggest that many species were associated with particular types of vegetation as measured by structural attributes of the forests.These species included large birds (American Crow (Corvus brachyrhynchos) and Red-winged Blackbird (Agelaius phoeniceus)) that forage on the ground in open habitats and small birds (Red-eyed Vireo (Vireo olivaceus), House Wren (Troglodytes aedon), Hooded Warbler (Setophaga citrina), and Prairie Warbler (Setophaga discolor)) that are associated with dense shrub cover.Except for the American Crow, which preys on eggs and nestlings of small song birds, none of the other 5 species is known to display direct interactions, so we suspect that the correlations may have been associated with species-specific responses to habitat components not adequately measured by our covariates.

View Article: PubMed Central - PubMed

Affiliation: Southeast Ecological Science Center, U.S. Geological Survey, Gainesville, Florida, United States of America.

ABSTRACT
We used repeated sightings of individual birds encountered in community-level surveys to investigate the relative roles of habitat and biological interactions in determining the distribution and abundance of each species. To analyze these data, we developed a multispecies N-mixture model that allowed estimation of both positive and negative correlations between abundances of different species while also estimating the effects of habitat and the effects of errors in detection of each species. Using a combination of single- and multispecies N-mixture modeling, we examined for each species whether our measures of habitat were sufficient to account for the variation in encounter histories of individual birds or whether other habitat variables or interactions with other species needed to be considered. In the community that we studied, habitat appeared to be more influential than biological interactions in determining the distribution and abundance of most avian species. Our results lend support to the hypothesis that abundances of forest specialists are negatively affected by forest fragmentation. Our results also suggest that many species were associated with particular types of vegetation as measured by structural attributes of the forests. The abundances of 6 of the 73 species observed in our study were strongly correlated. These species included large birds (American Crow (Corvus brachyrhynchos) and Red-winged Blackbird (Agelaius phoeniceus)) that forage on the ground in open habitats and small birds (Red-eyed Vireo (Vireo olivaceus), House Wren (Troglodytes aedon), Hooded Warbler (Setophaga citrina), and Prairie Warbler (Setophaga discolor)) that are associated with dense shrub cover. Species abundances were positively correlated within each size group and negatively correlated between groups. Except for the American Crow, which preys on eggs and nestlings of small song birds, none of the other 5 species is known to display direct interactions, so we suspect that the correlations may have been associated with species-specific responses to habitat components not adequately measured by our covariates.

No MeSH data available.


Related in: MedlinePlus

Schematic representation of the N-mixture model of correlated abundances for 3 species.Solid rectangles correspond to observed quantities (covariates or individual capture histories). Dashed circles correspond to latent random variables. Notation is described in Multispecies N-mixture model of correlated abundances. Covariates of abundance (LPC1, LPC2, VPC1) and detection probability (DAY OF YEAR, TIME OF DAY) are described in Statistical analysis of avian data.
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pone.0135987.g001: Schematic representation of the N-mixture model of correlated abundances for 3 species.Solid rectangles correspond to observed quantities (covariates or individual capture histories). Dashed circles correspond to latent random variables. Notation is described in Multispecies N-mixture model of correlated abundances. Covariates of abundance (LPC1, LPC2, VPC1) and detection probability (DAY OF YEAR, TIME OF DAY) are described in Statistical analysis of avian data.

Mentions: In this section we describe a multispecies N-mixture model that includes two components: (1) an ecological submodel that specifies the effects of habitat and biological interactions on species-specific abundances, and (2) an observational submodel that specifies the effects of sampling, detection probabilities, and abundances on species-specific, individual encounter histories. Fig 1 provides a schematic representation of this model using covariates of abundance and detection that were observed in our surveys of forest birds.


Estimating the Effects of Habitat and Biological Interactions in an Avian Community.

Dorazio RM, Connor EF, Askins RA - PLoS ONE (2015)

Schematic representation of the N-mixture model of correlated abundances for 3 species.Solid rectangles correspond to observed quantities (covariates or individual capture histories). Dashed circles correspond to latent random variables. Notation is described in Multispecies N-mixture model of correlated abundances. Covariates of abundance (LPC1, LPC2, VPC1) and detection probability (DAY OF YEAR, TIME OF DAY) are described in Statistical analysis of avian data.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4543583&req=5

pone.0135987.g001: Schematic representation of the N-mixture model of correlated abundances for 3 species.Solid rectangles correspond to observed quantities (covariates or individual capture histories). Dashed circles correspond to latent random variables. Notation is described in Multispecies N-mixture model of correlated abundances. Covariates of abundance (LPC1, LPC2, VPC1) and detection probability (DAY OF YEAR, TIME OF DAY) are described in Statistical analysis of avian data.
Mentions: In this section we describe a multispecies N-mixture model that includes two components: (1) an ecological submodel that specifies the effects of habitat and biological interactions on species-specific abundances, and (2) an observational submodel that specifies the effects of sampling, detection probabilities, and abundances on species-specific, individual encounter histories. Fig 1 provides a schematic representation of this model using covariates of abundance and detection that were observed in our surveys of forest birds.

Bottom Line: Our results also suggest that many species were associated with particular types of vegetation as measured by structural attributes of the forests.These species included large birds (American Crow (Corvus brachyrhynchos) and Red-winged Blackbird (Agelaius phoeniceus)) that forage on the ground in open habitats and small birds (Red-eyed Vireo (Vireo olivaceus), House Wren (Troglodytes aedon), Hooded Warbler (Setophaga citrina), and Prairie Warbler (Setophaga discolor)) that are associated with dense shrub cover.Except for the American Crow, which preys on eggs and nestlings of small song birds, none of the other 5 species is known to display direct interactions, so we suspect that the correlations may have been associated with species-specific responses to habitat components not adequately measured by our covariates.

View Article: PubMed Central - PubMed

Affiliation: Southeast Ecological Science Center, U.S. Geological Survey, Gainesville, Florida, United States of America.

ABSTRACT
We used repeated sightings of individual birds encountered in community-level surveys to investigate the relative roles of habitat and biological interactions in determining the distribution and abundance of each species. To analyze these data, we developed a multispecies N-mixture model that allowed estimation of both positive and negative correlations between abundances of different species while also estimating the effects of habitat and the effects of errors in detection of each species. Using a combination of single- and multispecies N-mixture modeling, we examined for each species whether our measures of habitat were sufficient to account for the variation in encounter histories of individual birds or whether other habitat variables or interactions with other species needed to be considered. In the community that we studied, habitat appeared to be more influential than biological interactions in determining the distribution and abundance of most avian species. Our results lend support to the hypothesis that abundances of forest specialists are negatively affected by forest fragmentation. Our results also suggest that many species were associated with particular types of vegetation as measured by structural attributes of the forests. The abundances of 6 of the 73 species observed in our study were strongly correlated. These species included large birds (American Crow (Corvus brachyrhynchos) and Red-winged Blackbird (Agelaius phoeniceus)) that forage on the ground in open habitats and small birds (Red-eyed Vireo (Vireo olivaceus), House Wren (Troglodytes aedon), Hooded Warbler (Setophaga citrina), and Prairie Warbler (Setophaga discolor)) that are associated with dense shrub cover. Species abundances were positively correlated within each size group and negatively correlated between groups. Except for the American Crow, which preys on eggs and nestlings of small song birds, none of the other 5 species is known to display direct interactions, so we suspect that the correlations may have been associated with species-specific responses to habitat components not adequately measured by our covariates.

No MeSH data available.


Related in: MedlinePlus