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- Boreal wetlands (3)
- Euphagus carolinus (3)
- Rusty Blackbird (3)
- Broadcast experiment (1)
- Choice (1)
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- Concurrent schedules of reinforcement (1)
- Detectability (1)
- Ecological trap (1)
- Foraging (1)
- Forest fragmentation (1)
- Home range (1)
- Monitoring (1)
- Nest survival (1)
- Nest-site selection (1)
- Occupancy (1)
- Patch selection (1)
- Patch-leaving decisions (1)
- Pigeons (1)
- Radio telemetry (1)
- Statistical decision theory (1)
- Wetland buffers (1)
Articles 1 - 4 of 4
Full-Text Articles in Life Sciences
Habitat Occupancy Of Rusty Blackbirds (Euphagus Carolinus) Breeding In Northern New England, Usa, Luke L. Powell, Thomas P. Hodgman, Ian J. Fiske, William E. Glanz
Habitat Occupancy Of Rusty Blackbirds (Euphagus Carolinus) Breeding In Northern New England, Usa, Luke L. Powell, Thomas P. Hodgman, Ian J. Fiske, William E. Glanz
Biology and Ecology Faculty Scholarship
The Rusty Blackbird (Euphagus carolinus), an uncommon songbird often associated with northern coniferous wetlands, has experienced a precipitous population decline since at least the early 20th century. Here, we provide the first analysis of breeding-habitat occupancy at the wetland scale and make recommendations for streamlined monitoring. We modeled occupancy and detectability as a function of site (i.e. habitat-based) and sampling (i.e. visit-specific) variables collected at 546 wetlands in northern New England, USA. Wetland occupancy (mean 6 SE ¼ 0.07 6 0.02 in randomly selected wetlands, and 0.12 6 0.02 in all wetlands surveyed) was best explained by variables …
Home Ranges Of Rusty Blackbirds Breeding In Wetlands: How Much Would Buffers From Timber Harvest Protect Habitat?, Luke L. Powell, Thomas P. Hodgman, William E. Glanz
Home Ranges Of Rusty Blackbirds Breeding In Wetlands: How Much Would Buffers From Timber Harvest Protect Habitat?, Luke L. Powell, Thomas P. Hodgman, William E. Glanz
Biology and Ecology Faculty Scholarship
We calculated the home ranges and core areas of 13 adult Rusty Blackbirds (Euphagus carolinus) in Maine to determine (1) the area requirements of breeding adults, (2) whether area requirements of the sexes and of colonial and noncolonial individuals differ, and (3) the proportion of the home range and core area that would be protected by a buffer of no logging of 50–100 m around occupied wetlands. Mean home ranges (37.5 ± 12.6 ha) and core areas (11.1 ± 2.8 ha) were large in comparison to those of other breeding icterids, and adults often foraged in multiple unconnected wetlands. Rusty …
Nest-Site Selection And Nest Survival Of The Rusty Blackbird: Does Timber Management Adjacent To Wetlands Create Ecological Traps?, Luke L. Powell, Thomas P. Hodgman, William E. Glanz, James D. Osenton, Caleb M. Fisher
Nest-Site Selection And Nest Survival Of The Rusty Blackbird: Does Timber Management Adjacent To Wetlands Create Ecological Traps?, Luke L. Powell, Thomas P. Hodgman, William E. Glanz, James D. Osenton, Caleb M. Fisher
Biology and Ecology Faculty Scholarship
Animals are subject to ecological traps when anthropogenic changes create habitat that appears suitable but when selected results in decreased fitness. The Rusty Blackbird (Euphagus carolinus) breeds in boreal wetlands and has declined by 85–95% over the last half century. We studied nest-site selection and daily nest survival rate (DSR) of 43 Rusty Blackbird nests in northern New England and evaluated whether regenerating logged areas adjacent to wetlands created ecological traps. Although nesting adults avoided high-canopied forests and selected areas with dense balsam fir (Abies balasmea) 1 to 3 m high, those characteristics were not associated …
Assessment And Choice: An Operant Simulation Of Foraging In Patches, John P. Roche, D. Alan Stubbs, William E. Glanz
Assessment And Choice: An Operant Simulation Of Foraging In Patches, John P. Roche, D. Alan Stubbs, William E. Glanz
Biology and Ecology Faculty Scholarship
Pigeons were presented with an operant simulation of two prey patches using concurrent random ratio schedules of reinforcement. An unstable patch offered a higher initial reinforcement probability, which then declined unpredictably to a zero reinforcement probability in each session. A stable patch offered a low but unvarying reinforcement probability. When the reinforcement probability declined to zero in a single step, the birds displayed shorter giving-up times in the unstable patch when the ratio between the initial reinforcement probabilities in the unstable and stable patches was greater and when the combined magnitude of the reinforcement probabilities in the two patches was …