Community Trophic Structure: The Roles of Diet, Body Size, and Activity Time in Vertebrate Predators

Musculoskeletal underpinnings to differences in killing behavior between North American accipiters (Falconiformes: Accipitridae) and falcons (Falconidae)

“…Larger animals are capable of producing relatively greater forces, and the scaling of underlying musculoskeletal characteristics typically reflects the increasing dietary (Emerson et al, 1994;Herrel et al, 2001Herrel et al, , 2004Aguirre et al, 2002;Ward et al, 2002;Erickson et al, 2003;van der Meij and Bout, 2004) and locomotory (Schmidt-Nielsen, 1984;Biewener, 1989Biewener, , 2005Polk, 2005) demands of increasing body size. In raptors, prey size tends to increase disproportionately with predator size (based on data from Bierregaard, 1978;Cade, 1982;Reynolds and Meslow, 1984;Johnsgard, 1990;Marti et al, 1993). Accordingly, I expected estimated digit and jaw forces (along with each of their musculoskeletal components) to scale with positive allometry.…”

Diet switching of seed-eating birds wintering in grazed habitats of the central Monte Desert, Argentina

“…No hay una razón para suponer a priori que la estructura gremial de una comunidad sea un atributo invariable , Hawkins y MacMahon 1989, Simberloff y Dayan 1991, Marti et al 1993a, 1993b. A pesar de que esta estructura podría variar tanto espacial como temporalmente, la mayor parte de los estudios de ensambles de aves que analizan su estabilidad han enfocado los aspectos espaciales (Landres y MacMahon 1980, Sabo y Holmes 1983, Holmes y Recher 1986, Jaksic y Delibes 1987, Jaksic et al 1991, Marti et al 1993a, Mac Nally 1994.…”

Trophic Structure of Raptor Communities: A Three-Continent Comparison and Synthesis

“…Some species may be closer in trophic niche space to mammalian carnivores and even snakes than to other rap tors , regardless of their activity time (Jaksic et aI., 1981;Jaksic and Delibes, 1987;Jaksic, 1988Jedrzejewski et al, 1989;Marti et al, 1993). Guild structure may result from convergence upon a few important prey species Jaksic, 1988Marti et al, 1993).…”

“…Some species may be closer in trophic niche space to mammalian carnivores and even snakes than to other rap tors , regardless of their activity time (Jaksic et aI., 1981;Jaksic and Delibes, 1987;Jaksic, 1988Jedrzejewski et al, 1989;Marti et al, 1993). Guild structure may result from convergence upon a few important prey species Jaksic, 1988Marti et al, 1993). Such convergence sometimes is the result of high abundance of a single prey species (Jaksic et aI., 1981) but may also be related to prey/predator size ratios (Jaksic and Delibes, 1987;Jaksic, 1989b;Marti et a1., 1993).…”