Wing loadings, wing shapes, and flight capabilities of procellariiformes

Abstract

Among 48 procellariiform species wing loading increases with increasing body weight. Mean total wing area varies allometrically with mean body weight: log 10 wing area (cm 2 )=20.42 log 10 body weight (g)0.588. The power exponent is significantly less than the 0.666 value expected from the law of similitude. Pelecanoides, with wings highly modified for diving, is an exception to the above trend. With increasing size the petrel wing becomes longer and narrower, aspect ratios increasing from about 6.5 in small storm petrels to about 15.6 in the giant albatrosses. Elongation is accompanied by changes in the proportions of the arm bones; the terminal segment, composed of the manus and primary feathers, becomes proportionately smaller and the inner segments, supported by the humerus and radio-ulna, proportionately larger with increasing body size. Some ecological correlates of interspecific differences in wing loadings and shapes are discussed. INTRODUCTIONThis paper presents data on variations in wing loadings, wing spans, and wing shapes with body size, as measured by body weight. Such information is necessary to understand and compare modes of flight, flight capabilities, feeding techniques, and other aspects of petrel ecology. It is hoped also that the data may be useful to those wishing to calculate other flight parameters like span loading and lift coefficients.

Wing Ecomorphology of Seabirds from Johnston Atoll

“…Our results for the two shearwaters agree closely with those of Warham (1977Warham ( , 1996. Analysis of individual specimens showed a significant correlation among body mass, wing loading, aspect ratio, wing span, and wing area (r > 0.59, P < 0.001 for all variables).…”

“…Christmas Shearwaters also pursuit dive (underwater flight) more frequently than do Wedge-tailed Shearwaters (Ashmole 1971), so a higher wing loading (smaller wing area) might reflect this behavior given the greater force required to move the wings through water relative to air. In support of this idea, a relatively high wing loading was reported for diving-petrels and alcids, both of which use wing propulsion underwater to pursue their prey (Warham 1977(Warham , 1996. More information is needed on the energetics and feeding behavior of these shearwaters.…”

“…Given these physiological and behavioral adaptations, it is expected that morphological adaptations also exist for proficient flight. Warham (1977Warham ( , 1996 presented data for several procellariiform species that revealed how wing morphology reflected ecology. For exam-' Received 2 July 1998.…”

Foraging and provisioning strategies of the light-mantled sooty albatross at South Georgia: competition and co-existence with sympatric pelagic predators

“…Although no recent counts of LMSAs are available for South Georgia, an estimated 5000 breeding pairs were present in 1976-1977(Thomas et al 1983. Given the typically biennial breeding pattern in this species, but with some re-nesting in consecutive years by failed breeders, the total size of the population at South Georgia is considered to be ca.…”

The effects of intense wing molt on diving in alcids and potential influences on the evolution of molt patterns

“…The more generally accepted explanation for intense wing molt in alcids and other species with high wing loading (e.g. waterfowl) postulates that almost any reduction in wing area, even that resulting from a relatively slow sequential wing molt, would cause wing-loading to approach the theoretical maximum for aerial flight, approximately 2.5·g·cm -2 (Meunier, 1951;Storer, 1960Storer, , 1971Warham, 1977;Pennycuick, 1987;Livezey, 1988). In other words, the loss of one or two feathers, as would occur with a gradual molt, may render a bird with especially high wing loading flightless, or nearly so.…”