Pellet (ornithology)
A pellet, in ornithology, is the mass of undigested parts of a bird's food that some bird species occasionally regurgitate. The contents of a bird's pellet depend on its diet, but can include the exoskeletons of insects, indigestible plant matter, bones, fur, feathers, bills, claws, and teeth. In falconry, the pellet is called a casting.
The passing of pellets allows a bird to remove indigestible material from its
Ornithologists may collect one species' pellets over time to analyze the seasonal variation in its eating habits. One advantage of collecting pellets is that it allows for the determination of diet without the killing and dissection of the bird. Pellets are found in different locations, depending on the species. In general, these are roosting and
Ornithologists examining pellets have discovered unusual items in them—even
The hair, bones and other body parts (such as limbs, skin fragments, and even faeces) of
In falconry
In falconry, casting involves giving a hawk roughage, which is regurgitated later to purge and cleanse its crop. Hawks in the wild will produce castings of their own accord, in the form of small pellets of fur, feathers, and other indigestible material, regurgitated hours after it has eaten. Of the roughage used for falcons in captivity, there are two kinds: plumage, and cotton; the latter of which is generally in pellets about the size of hazelnuts, made of soft fine cotton, and conveyed into the hawk's gorge after supper. In the morning, the hawk will have cast them out, at which time they should be examined for color and condition to determine the state of the hawk's body. If they are cast out round, white, without stench, nor very moist, then the hawk is healthy; if otherwise, particularly black, green, slimy, or the like, the hawk is ill.[4]
The casting of plumage is examined in the same manner. The yellow
Casting will occur at the same time daily, provided that hawks are flown at the same time daily. Hawks in captivity are usually weighed immediately before being flown. If they were fed roughage the previous day, they should cast it out before being weighed, to avoid an inaccurate measurement.[5]
Casting is a necessary part of a hawk's survival. Not only does it clear out the crop, but the roughage that is regurgitated cleans bacteria from the walls of the crop. If hawks in captivity are not provided with this necessary roughage, and instead are simply fed meat, they will become seriously ill and unreleasable into the wild.[6]
References
- ^ ISBN 0-394-46651-9
- PMID 16011429.
- ^ Sike T, Rózsa L 2006. Owl pellet avoidance in yellow-necked field mice Apodemus flavicollis and house mice Mus musculus. Acta Zoologica Academiae Scientiarum Hungaricae, 52, 77–80.
- ^ This article incorporates text from a publication now in the public domain: Chambers, Ephraim, ed. (1728). Cyclopædia, or an Universal Dictionary of Arts and Sciences (1st ed.). James and John Knapton, et al.
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(help) - ^ ISBN 0-7137-2588-5. p 23.
- ^ Elsberry, Wesley R. "Falconry Jargon". Austringer. URL accessed 2006-05-30.