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Petrochelidon pyrrhonota (Cliff Swallow) is experiencing significant population declines in parts of its breeding range, particularly in northeastern North America. At 12 active Cliff Swallow colonies in western Massachusetts in 2019–2020, we examined the extent to which installation of artificial nests, providing of mud sources, and control of Passer domesticus (House Sparrow) affected colony size and reproductive success of Cliff Swallows. While there was a trend for colony size to increase at sites with artificial nests, there was not a significant size increase at these sites from 2019–2020. Cliff Swallow nesting success was significantly lower at colony sites where House Sparrows were present, compared to those at which they were absent. The number of nesting Cliff Swallows at 2 sites where mud sources were enhanced increased from 2019 to 2020. Efforts to control House Sparrows by shooting at 1 site were unsuccessful. Our study suggests that without effective control of House Sparrows, Cliff Swallows are likely to keep declining in Massachusetts, regardless of other management techniques used.
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Notes on the Natural History and Climatic Specializations of an Endemic Caribbean Paper Wasp (Hymenoptera: Vespidae: Mischocyttarus phthisicus)
Mischocyttarus phthisicus is a locally abundant social wasp in Puerto Rico with little known of its natural history. Using our own on-site observations and citizen-science reports from iNaturalist, we compiled data on and described this species’ occurrence, nesting biology, and colony size. To understand the degree of its climatic specialization, we also compared thermal tolerance across elevations. Nests were most often found on the undersides of broad leaves and were comparable in size to nests of congeners, though likely slightly larger. Heat tolerance, but not cold tolerance, changed with elevation, a result which does not follow Brett’s rule.
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- Award ID(s):
- 1831952
- PAR ID:
- 10567447
- Publisher / Repository:
- The Eagle Hill Institute
- Date Published:
- Journal Name:
- The Caribbean Naturalist
- ISSN:
- 2326-7119
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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