The indirect effects of predators on nonadjacent trophic levels, mediated through traits of intervening species, are collectively known as trait-mediated trophic cascades. Although birds are important predators in terrestrial ecosystems, clear examples of trait-mediated indirect effects involving bird predators have almost never been documented. Such indirect effects are important for structuring ecological communities and are likely to be negatively impacted by habitat fragmentation, climate change, and other factors that reduce abundance of top predators.
View Article and Find Full Text PDFWilliam Bartram described the Painted Vulture (Vultur sacra) as a new species in his 1791 book on travels in Florida and other southeastern states. However, no specimen of this bird survives, and it has not been reported by any subsequent ornithologist. Bartram's detailed description is not presently endorsed by the American Ornithologists' Union and has been widely regarded as a myth, a misdescribed King Vulture Sarcoramphus papa (Linnaeus), a misdescribed Northern Caracara Caracara cheriway (Jacquin), or a garbled mixture of species.
View Article and Find Full Text PDFBeetles of the family Lycidae have long been known to be chemically protected. We present evidence that North American species of the lycid genera Calopteron and Lycus are rejected by thrushes, wolf spiders, and orb-weaving spiders, and that they contain a systemic compound that could account, at least in part, for this unacceptability. This compound, a novel acetylenic acid that we named lycidic acid, proved actively deterrent in feeding tests with wolf spiders and coccinellid beetles.
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