Gastric digestion in some raptors

Damage to Bird Bones in Pellets of GyrfalconFalco rusticolus

“…This is consistent with the comparative studies (on small mammal victims) done by Duke et al (1975) and Andrews (1990). Gyrfalcons also produce more breakages of their bird victims' bones than any of the owls.…”

Postprandial response of gastric pH in leopard sharks (Triakis semifasciata)and its use to study foraging ecology

“…Evans et al, 1988;Gardner et al, 2002). As with leopard sharks, a rise in gastric pH with meal ingestion, followed by a decrease to baseline levels, has been observed for birds (Duke et al, 1975;Peters, 1997a;Gremillet et al, 2000) and humans (James, 1957;Gardner et al, 2002). Humans continuously secrete acid, with an unstimulated (i.e.…”

Corroded, Thinned and Polished Bones Created by Golden Eagles (Aquila chrysaetos): Taphonomic Implications for Archaeological Interpretations

“…Experimental research on captive raptors (Duke et al, 1975;Dodson & Wexlar, 1979;Hoffman, 1988) and studies of raptor pellets collected in natural settings (Hockett, 1989(Hockett, , 1991Andrews, 1990) have clearly shown that the pellets of diurnal birds of prey such as harriers, hawks, kestrels, and eagles contain fewer bones and bones that exhibit greater corrosive damage than those found in owl pellets (Mayhew, 1977: 25;Korth, 1979: 240;Andrews, 1990: 26). The fewer bones in diurnal raptor pellets, however, can only partially be attributed to stronger gastric fluids because diurnal raptors often swallow fewer bones during feeding than do owls (Andrews, 1990: 28).…”