Research Interests: Landscape Ecology, Geography, Conservation Biology, Ecology, Urbanization, and 14 moreLand Use, Scale, Breeding Bird Survey, Habitat Selection, Species Distribution, Species Richness, Habitat loss, Green Space, Spatial Variation, Migratory Birds, Urban Ecosystems, Large Scale, Ecological Applications, and Southeastern United States
Birds have been associated with forests as long as there have been birds. Since their origin, birds have diversified to occupy a remarkable array of habitats and foraging strategies, unparalleled by any other terrestrial vertebrate. Over... more
Birds have been associated with forests as long as there have been birds. Since their origin, birds have diversified to occupy a remarkable array of habitats and
foraging strategies, unparalleled by any other terrestrial vertebrate. Over the eons,
birds have formed intimate relationships between their habitats, their prey, and formed tight
symbiotic relationships, such as flower-pollinator symbiosis. Because the majority of birds are
conspicuous and relatively easy to study, they are among the best studied animals in forested
ecosystems.
Despite their relative ease of being detected, new birds are still being discovered, particularly
in the rainforests of the Neotropics and Southeast Asia. Currently, there are between approximately 10,300 (www.birdlife.org/datazone/info/
taxonomy; www.birds.cornell.edu/clementschecklist) to 10,546 accepted extant species of birds. The exact number of avian species is unknown since we
still debate species concepts, new species are still being discovered, and the loss of species
through extinctions is happening in real time. The importance
of forests to birds cannot be overstated: forests are home to about 75 percent of avian species
and comprise the primary habitat of the majority of bird species. The
highest diversity of birds (>5,000 species) occurs in lowland tropical and subtropical forests near
the Equator in the Americas and Africa and 25°N in Southeast Asia and declines towards the
poles.
foraging strategies, unparalleled by any other terrestrial vertebrate. Over the eons,
birds have formed intimate relationships between their habitats, their prey, and formed tight
symbiotic relationships, such as flower-pollinator symbiosis. Because the majority of birds are
conspicuous and relatively easy to study, they are among the best studied animals in forested
ecosystems.
Despite their relative ease of being detected, new birds are still being discovered, particularly
in the rainforests of the Neotropics and Southeast Asia. Currently, there are between approximately 10,300 (www.birdlife.org/datazone/info/
taxonomy; www.birds.cornell.edu/clementschecklist) to 10,546 accepted extant species of birds. The exact number of avian species is unknown since we
still debate species concepts, new species are still being discovered, and the loss of species
through extinctions is happening in real time. The importance
of forests to birds cannot be overstated: forests are home to about 75 percent of avian species
and comprise the primary habitat of the majority of bird species. The
highest diversity of birds (>5,000 species) occurs in lowland tropical and subtropical forests near
the Equator in the Americas and Africa and 25°N in Southeast Asia and declines towards the
poles.
Research Interests: Evolutionary Biology, Environmental Science, Environmental Economics, Forestry, Ornithology, and 27 moreScience Education, Ecosystem Services, Conservation Biology, Conservation, Environmental Studies, Ecological Economics, Community Ecology, Tropical Ecology, Biodiversity and Ecosystem Function, Forest Ecology And Management, Biology, Seed Dispersal, Ecology, Evolution, Pollination, Predator-Prey Interactions, Biogeography, Biodiversity, Forest Ecology, Environmental Sustainability, Wildlife Conservation, Food web ecology, Biodiversity Conservation, Biodiversity Research, Tropical Forest Ecology, Birds, and Scavenging
Research Interests:
Many insectivorous birds of the tropical rainforest understory, particularly terrestrial species, are prone to local extinctions in fragmented forests. We evaluated the hypothesis that vegetation structural changes in rainforest fragments... more
Many insectivorous birds of the tropical rainforest understory, particularly terrestrial species, are prone to local extinctions in fragmented forests. We evaluated the hypothesis that vegetation structural changes in rainforest fragments reduce the availability of microhabitats used by terrestrial insectivores. Near Manaus, Brazil, we compared the vegetation in forest fragments to the vegetation in a continuous forest site where nine species of terrestrial insectivores were observed foraging. Our focal species included those that are extinction prone in fragments (Myrmornis torquata [Wing-banded Antbird], Grallaria varia [Variegated Antbird], Hylopezus macularius [Spotted Antpitta]), a fragmentation-tolerant species (Myrmothera campanisona [Thrush-like Antpitta]), and species that have and intermediate response (Myrmeciza ferruginea [Ferruginous-backed Antbird], Formicarius colma [Rufous-capped Anttrush], Formicarius analis [Black-faced Antthrush], Conopophaga aurita [Chestnut-belted Gnateater], and Corythopis torquata [Ringed Antpipit]). To quantify vegetation, we measured sixteen habitat variables in 8-m radius plots where birds were observed foraging as well as random points in continuous forest and forest fragments of 1-, 10-, and 100-ha. Four principal components were produced from a principal component analysis and we selected a variable (leaf litter depth, plant cover 3–10 m, density of plants 1–2 m, and plant cover >20 m) from each principal component for our fragment vs continuous forest comparisons. Using Markov chain Monte Carlo (MCMC) simulation, we estimated the probabilities that the density of plants 1–2 m, proportion of plant cover 3–10 m, and leaf litter depth increased with decreasing fragment area and also exceeded the values associated with fragmentation-sensitive species. We also tested the prediction that plant cover >20 m decreased in forest fragments and that those sites became more open than typical sites used by our focal species. Our predictions were strongly supported: decreasing fragment size was correlated with increasing density of tall plants, increasing mid-story vegetation cover, decreased canopy cover, and increasing leaf litter depth. Even if our focal species are able to disperse to small forest fragments, our results suggest that they may not find enough appropriate habitat.