Foraging efficiency

Mpller, A. P., Biard, C., Blount, J. D., Houston, D. C., Ninni, P., Saino, N., and Surai, P. F. 2000. Carotenoid-dependent signals Indicators of foraging efficiency, immunocompetence, or detoxification ability Avian Poult. Biol. Rev. 11 137-159. 

Using experimental procedure (2) above, Jaeger et al. (1981) allowed individuals of Plethodon cinereus to forage in their own marked territories, in territories previously marked by conspecifics, and in an unmarked control area. Results showed that foraging efficiency (capture rates, net caloric gain) decreased in the second and third conditions compared to the first. 

Metzgar, 1976). Another selection pressure that may be more important, is that the owner is more likely to be killed by a predator if it is defeated and expelled into a completely unfamilar area than an intruder which simply continues with its non-territorial existence. This danger is most acute in a short period after defeat when the owner risks its life. This is in contrast to the loss of knowledge about the territory s resources where the owner may temporarily lose foraging efficiency. 

It is much easier to improve soil structure and fertility before rather than after planting, and this is crucial to give trees, bushes, and canes a head start. A plant that establishes well soon develops an extensive root system that can forage for water and nutrients more efficiently than a weak plant. Details of appropriate soil improvement are given under individual fruits. Perennial weeds are awkward to remove from growing fruit, so clear the ground well before planting, too (see pp.78-8D. 

Genetic selection for commercial turkey production has resulted in broad-breasted varieties that have rapid growth and high feed-conversion efficiency. The modem varieties have lost their natural ability to fly or forage for feed. Artificial insemination is routinely used with turkey breeders to avoid injury of the hens by the much larger toms and because the broad breasts have resulted in most males having a conformation that renders them incapable of natural mating. 

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