Abstract Nests and nesting behavior of the Nightingale Wren (Microcerculus marginatus) in Panama ... more Abstract Nests and nesting behavior of the Nightingale Wren (Microcerculus marginatus) in Panama are described. Two nests were found at the ends of horizontal burrows in dirt banks, presumably excavated by other species. The nest chambers were lined with dead leaf fragments. Clutch sizes were two and three eggs. Incubation period was 19 or 20 days for one nest, and the nestling period was 16 or 17 days for the second nest. A comparison of nests in the Troglodytidae shows the nests of M. marginatus to be most similar to those of the genera Salpinctes, Catherpes, and Hylorchilus, all of which are secondary cavity nesters. If nest type is a phylogenetically conserved characteristic, then these four genera may be more closely related than is reflected in current classifications.
Marine bird surveys are primarily conducted during diurnal periods, thus our understanding of the... more Marine bird surveys are primarily conducted during diurnal periods, thus our understanding of their ecology and distribution is biased; our understanding of Surf Scoter (Melanitta perspicillata) distribution is no different. Diurnal data currently guides conservation and management decisions regarding this declining species. Our research objectives were to 1) determine nocturnal use area habitat characteristics in the Salish Sea, 2) determine influencing factors of selection of nocturnal use, and 3) develop predictive models to estimate likely nocturnal use areas across the Salish Sea and assess vulnerabilities to potential oils spills or increased shipping traffic. We used existing Surf Scoter Platform Terminal Transmitter (PTT) data, provided by The Washington Department of Fish and Wildlife (WDFW) and various spatial layers in a GIS to identify habitat characteristics of nocturnal locations and to measure distances traveled between diurnal foraging and nocturnal resting areas. Results indicated that Scoters will travel an average of 3,967 m from diurnal foraging areas to nocturnal habitats. We implemented a use versus pseudo-non-use resource selection design, using logistic regression, and Akaike’s information criterion (AIC) to create a predictive model for nocturnal Scoter presence in the Salish Sea. Our resulting model identified distance to shore, water depth, tidal current and vessel traffic as strong predictors of nocturnal presence. Determining marine nocturnal use habitat characteristics fills an important data gap in understanding the winter ecology of Surf Scoters. Our results provide guidance for better management of over-wintering seabirds in the Salish Sea and inform oil spill response preparedness efforts
ABSTRACT Eciton burchellii is a Neotropical army ant that consumes a variety of arthropods captur... more ABSTRACT Eciton burchellii is a Neotropical army ant that consumes a variety of arthropods captured during swarm raids. Wasp larvae and pupae provide an important food source for E. burchellii, and this ant species is thought to be a major predator on immature wasps in many Neotropical areas. Some birds also prey on wasp brood. Numerous bird species regularly follow E. burchellii swarms but are thought to typically avoid eating army ants. Rather, the birds feed on the arthropods that the ant swarms flush from the leaf litter. I report observations of ant-following birds, the Gray-headed Tanager Eucometis penicillata and the Flame-colored Tanager Piranga bidentata consuming E. burchellii workers that were carrying Polistinae wasp larvae and pupae. It has been suggested that ant-following birds may impose a cost to army ants by consuming arthropods and competing with ants for food resources. Also, it has been speculated that army ants emigrate at night to avoid the loss of their brood to birds, but lack of ...
Decades of forest loss throughout Central America have dramatically reduced the amount of forest ... more Decades of forest loss throughout Central America have dramatically reduced the amount of forest habitat available for Neotropical-Nearctic migratory songbirds. Forest fragments compose the dominant form of forest habitat across lowland Central America; yet little is known about the relative use of fragments or the minimum patch size required by wintering migrant songbirds. From results of playback surveys, area-based density estimates, and population modeling for a declining species of migrant, the Wood Thrush (Hylocichla mustelina), I compared the relative occupancy of forest fragments (0.5 ha to < 400 ha) and continuous forest of adjacent La Selva Biological Reserve (La Selva) for this species. Wood Thrushes occupied all surveyed forest fragments that were 1 ha. Mean densities were highest in large, continuous forests of La Selva. When compared along a fragment class size gradient, no difference in Wood Thrush densities was detected across three fragment size classes. Using ...
Revista Latinoamericana De Conservacion Latin American Journal of Conservation, 2011
... 0114304 to the University of Idaho, and with assistance from Steve and Barbara Roberts. While... more ... 0114304 to the University of Idaho, and with assistance from Steve and Barbara Roberts. While in Costa Rica, logistical support was provided by La Selva ... Morse WC, Schedlbauer JL, Sesnie SE, Finegan B, Harvey CA, Hollenhorst SJ, Kavanagh KL, Stoian D &amp; JD Wulfhorst. ...
Diurnally biased monitoring and research dominate our ecological understanding and guide conserva... more Diurnally biased monitoring and research dominate our ecological understanding and guide conservation and management decisions regarding important indicator sea duck species, such as Surf Scoters (Melanitta perspicillata). Advances in telemetry technology are improving our ability to track wildlife across the entire 24-hr day. Using location data derived from birds with surgically implanted satellite transmitters and habitat layers within a GIS (geographic information system), we analyzed Surf Scoter location data to (1) estimate movement distances between diurnal and nocturnal sites, (2) assess differences in environmental conditions at diurnal and nocturnal use locations, (3) evaluate the environmental conditions influencing nocturnal habitat selection, and (4) develop a predictive model to estimate likely nocturnal resting areas across the Salish Sea, which is composed of the inland marine waters of British Columbia, Canada, and Washington State. Surf Scoters in the Salish Sea tr...
Bird species observed at swarms of army ants, Eciton burchelli and Labidus praedator, in Chiriqui... more Bird species observed at swarms of army ants, Eciton burchelli and Labidus praedator, in Chiriqui Province, Panama, at elevations between 1400 m and 1800 m during February through June, 1996 and 1997.
Canada’s boreal forest region provides one of the last opportunities for freshwater and intact fo... more Canada’s boreal forest region provides one of the last opportunities for freshwater and intact forest protection that has globally significant implications. This region contains a significant proportion of the world’s surface freshwater, including a relatively large proportion of the planet’s wetlands intermingled with the most intact forest ecosystems on Earth. The boreal forest is defined by water as much as by forest, a fact that is too often underappreciated. The sheer abundance of water can make it seem limitless, but this is far from the case. Continued overexploitation and degradation of freshwater resources and ecosystems, particularly peatlands, across the boreal forest has consequences for climate cycles, nutrient cycles and livelihoods of the peoples that depend on this water for life.
The International Boreal Conservation Science Panel is an interdisciplinary team of scientists fr... more The International Boreal Conservation Science Panel is an interdisciplinary team of scientists from the U.S. and Canada. Its members have a wide range of expertise and experience gained from years of research, conservation, and writing about science issues related to North America and many other parts of the world. The panel is jointly concerned with the future of North America’s boreal forest and in ensuring that the scientific issues related to the conservation of the boreal forest are clearly articulated to the public and decision-makers in government and industry. The panel enlists its member specialists and invited expert associates in producing science/policy briefing notes for issues of major relevance to the future of the boreal forest.
We studied avian attendance at swarms of Eciton burchelli and Labidus praedator (Hymenoptera: For... more We studied avian attendance at swarms of Eciton burchelli and Labidus praedator (Hymenoptera: Formicidae: Ecitoninae) over 5-mo periods in both 1996 and 1997, at elevations between 1400 m and 1800 m in western Panama. We conducted area searches for ...
Abstract Nests and nesting behavior of the Nightingale Wren (Microcerculus marginatus) in Panama ... more Abstract Nests and nesting behavior of the Nightingale Wren (Microcerculus marginatus) in Panama are described. Two nests were found at the ends of horizontal burrows in dirt banks, presumably excavated by other species. The nest chambers were lined with dead leaf fragments. Clutch sizes were two and three eggs. Incubation period was 19 or 20 days for one nest, and the nestling period was 16 or 17 days for the second nest. A comparison of nests in the Troglodytidae shows the nests of M. marginatus to be most similar to those of the genera Salpinctes, Catherpes, and Hylorchilus, all of which are secondary cavity nesters. If nest type is a phylogenetically conserved characteristic, then these four genera may be more closely related than is reflected in current classifications.
Marine bird surveys are primarily conducted during diurnal periods, thus our understanding of the... more Marine bird surveys are primarily conducted during diurnal periods, thus our understanding of their ecology and distribution is biased; our understanding of Surf Scoter (Melanitta perspicillata) distribution is no different. Diurnal data currently guides conservation and management decisions regarding this declining species. Our research objectives were to 1) determine nocturnal use area habitat characteristics in the Salish Sea, 2) determine influencing factors of selection of nocturnal use, and 3) develop predictive models to estimate likely nocturnal use areas across the Salish Sea and assess vulnerabilities to potential oils spills or increased shipping traffic. We used existing Surf Scoter Platform Terminal Transmitter (PTT) data, provided by The Washington Department of Fish and Wildlife (WDFW) and various spatial layers in a GIS to identify habitat characteristics of nocturnal locations and to measure distances traveled between diurnal foraging and nocturnal resting areas. Results indicated that Scoters will travel an average of 3,967 m from diurnal foraging areas to nocturnal habitats. We implemented a use versus pseudo-non-use resource selection design, using logistic regression, and Akaike’s information criterion (AIC) to create a predictive model for nocturnal Scoter presence in the Salish Sea. Our resulting model identified distance to shore, water depth, tidal current and vessel traffic as strong predictors of nocturnal presence. Determining marine nocturnal use habitat characteristics fills an important data gap in understanding the winter ecology of Surf Scoters. Our results provide guidance for better management of over-wintering seabirds in the Salish Sea and inform oil spill response preparedness efforts
ABSTRACT Eciton burchellii is a Neotropical army ant that consumes a variety of arthropods captur... more ABSTRACT Eciton burchellii is a Neotropical army ant that consumes a variety of arthropods captured during swarm raids. Wasp larvae and pupae provide an important food source for E. burchellii, and this ant species is thought to be a major predator on immature wasps in many Neotropical areas. Some birds also prey on wasp brood. Numerous bird species regularly follow E. burchellii swarms but are thought to typically avoid eating army ants. Rather, the birds feed on the arthropods that the ant swarms flush from the leaf litter. I report observations of ant-following birds, the Gray-headed Tanager Eucometis penicillata and the Flame-colored Tanager Piranga bidentata consuming E. burchellii workers that were carrying Polistinae wasp larvae and pupae. It has been suggested that ant-following birds may impose a cost to army ants by consuming arthropods and competing with ants for food resources. Also, it has been speculated that army ants emigrate at night to avoid the loss of their brood to birds, but lack of ...
Decades of forest loss throughout Central America have dramatically reduced the amount of forest ... more Decades of forest loss throughout Central America have dramatically reduced the amount of forest habitat available for Neotropical-Nearctic migratory songbirds. Forest fragments compose the dominant form of forest habitat across lowland Central America; yet little is known about the relative use of fragments or the minimum patch size required by wintering migrant songbirds. From results of playback surveys, area-based density estimates, and population modeling for a declining species of migrant, the Wood Thrush (Hylocichla mustelina), I compared the relative occupancy of forest fragments (0.5 ha to < 400 ha) and continuous forest of adjacent La Selva Biological Reserve (La Selva) for this species. Wood Thrushes occupied all surveyed forest fragments that were 1 ha. Mean densities were highest in large, continuous forests of La Selva. When compared along a fragment class size gradient, no difference in Wood Thrush densities was detected across three fragment size classes. Using ...
Revista Latinoamericana De Conservacion Latin American Journal of Conservation, 2011
... 0114304 to the University of Idaho, and with assistance from Steve and Barbara Roberts. While... more ... 0114304 to the University of Idaho, and with assistance from Steve and Barbara Roberts. While in Costa Rica, logistical support was provided by La Selva ... Morse WC, Schedlbauer JL, Sesnie SE, Finegan B, Harvey CA, Hollenhorst SJ, Kavanagh KL, Stoian D &amp; JD Wulfhorst. ...
Diurnally biased monitoring and research dominate our ecological understanding and guide conserva... more Diurnally biased monitoring and research dominate our ecological understanding and guide conservation and management decisions regarding important indicator sea duck species, such as Surf Scoters (Melanitta perspicillata). Advances in telemetry technology are improving our ability to track wildlife across the entire 24-hr day. Using location data derived from birds with surgically implanted satellite transmitters and habitat layers within a GIS (geographic information system), we analyzed Surf Scoter location data to (1) estimate movement distances between diurnal and nocturnal sites, (2) assess differences in environmental conditions at diurnal and nocturnal use locations, (3) evaluate the environmental conditions influencing nocturnal habitat selection, and (4) develop a predictive model to estimate likely nocturnal resting areas across the Salish Sea, which is composed of the inland marine waters of British Columbia, Canada, and Washington State. Surf Scoters in the Salish Sea tr...
Bird species observed at swarms of army ants, Eciton burchelli and Labidus praedator, in Chiriqui... more Bird species observed at swarms of army ants, Eciton burchelli and Labidus praedator, in Chiriqui Province, Panama, at elevations between 1400 m and 1800 m during February through June, 1996 and 1997.
Canada’s boreal forest region provides one of the last opportunities for freshwater and intact fo... more Canada’s boreal forest region provides one of the last opportunities for freshwater and intact forest protection that has globally significant implications. This region contains a significant proportion of the world’s surface freshwater, including a relatively large proportion of the planet’s wetlands intermingled with the most intact forest ecosystems on Earth. The boreal forest is defined by water as much as by forest, a fact that is too often underappreciated. The sheer abundance of water can make it seem limitless, but this is far from the case. Continued overexploitation and degradation of freshwater resources and ecosystems, particularly peatlands, across the boreal forest has consequences for climate cycles, nutrient cycles and livelihoods of the peoples that depend on this water for life.
The International Boreal Conservation Science Panel is an interdisciplinary team of scientists fr... more The International Boreal Conservation Science Panel is an interdisciplinary team of scientists from the U.S. and Canada. Its members have a wide range of expertise and experience gained from years of research, conservation, and writing about science issues related to North America and many other parts of the world. The panel is jointly concerned with the future of North America’s boreal forest and in ensuring that the scientific issues related to the conservation of the boreal forest are clearly articulated to the public and decision-makers in government and industry. The panel enlists its member specialists and invited expert associates in producing science/policy briefing notes for issues of major relevance to the future of the boreal forest.
We studied avian attendance at swarms of Eciton burchelli and Labidus praedator (Hymenoptera: For... more We studied avian attendance at swarms of Eciton burchelli and Labidus praedator (Hymenoptera: Formicidae: Ecitoninae) over 5-mo periods in both 1996 and 1997, at elevations between 1400 m and 1800 m in western Panama. We conducted area searches for ...
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