116 J. Christopher Haney et al. 



ly few at-sea observations of either soft-plumaged or related northern 

 populations have been made away from their breeding areas (Collar 

 and Stuart 1985). We report such a sighting from the waters off the 

 southeastern United States and provide some field marks (see also 

 Enticott 1991) that may be useful for differentiating forms within a 

 difficult taxonomic complex formerly regarded as a single species (Bourne 

 1983a). 



Sighting description — On 9 November 1984, two of us (J.C.H. 

 and C.A.F.) observed an unusual gadfly petrel with other pro- 

 cellariiforms during a census of seabirds at the edge of the continental 

 shelf off the Georgia coast. A mixed flock (30-40 individuals) of the 

 black-capped petrel, Pterodroma hasitata (Kuhl), Cory's shearwater, 

 Calonectris diomedea (Scopoli), greater shearwater, Puffinus gravis 

 (O'Reilly), and Audubon's shearwater, Puffinus Iherminieri Lesson, accom- 

 panied by pomarine jaegers, Stercorarius pomarinus (Temminck), and 

 herring gulls Larus argentatus Pontoppidan, was seen feeding over a 

 fish school near the western frontal boundary of the Gulf Stream at 

 31°39'N, 79°24'W. This was approximately 145 km due east of St. 

 Catherine's Island, Georgia (depth 250 m, surface temperature 25.5C). 

 We initially noticed a gadfly petrel without a white nape or rump in 

 the feeding flock at 1625 EST. During the next 15 minutes, we 

 watched from opposite ends of the stationary research vessel while 

 the bird flew and foraged with other seabirds. It was seen from as 

 close as 30 m through 9 x 35 and 10 x 40 binoculars. 



J. C. Haney noted that, compared with the high bounding flight 

 of nearby black-capped petrels, this gadfly petrel had more rapid wing- 

 beats and flew closer to the ocean surface. It was not noticeably 

 different in size from the black-capped petrel, and like that species, it 

 alternated banking and gliding with first the dorsal and then the ventral 

 surface exposed to the observers. The bird's overall appearance was 

 dark gray above and white below. The gray tail was wedge-shaped 

 and slightly paler than the back, without light-colored upper tail coverts. 

 The crown appeared darker than the nape and hindneck, and the 

 forehead was white. No dark facial mask around the eye was observed. 

 There was conspicuous mottling or streaking along the bird's flanks. 

 This field mark was very obvious and set the bird apart from nearby 

 black-capped petrels which have clear white flanks. The bird did not 

 have a complete breast band, although it did have a short, ventrally- 

 projecting light gray bar on both sides of the neck in front of the 

 wings. C. A. Faanes noticed that the underwing coverts were noticeably 

 gray to the base of the primaries. The primary feathers appeared 

 white-based, reminiscent of a jaeger in flight, suggesting that the bird 

 may have been molting its wing coverts at the time. The upperwings 



