RECOGNIZING BONAPARTE'S. 
     
     LITTLE, AND BLACK- 
     
     HEADED GULLS -THREE 
     
     SIMILAR SPECIES 
     
    
   
   
    
     — 
     
    
   
   
    
        
     
         
     
    
   
   
    
     by Geoff Hogan 
     
    
   
   
    
     Identifying guTTs to species and age 
     
     cTass is not difficuTt when using the usuaT 
     
     fier marks, and is something that more peopTe 
     
     are finding enjoyment in. No Tonqer are aTT guTTs 
     
     simoTy “seaguTTs” (a tenn frowned upon by ornithoTogists) 
     
     but instead we have Herring, Ring-biTTed, Greater bTack- 
     
     backed, IceTand, GTaucous guTTs and others. To be more 
     
     precise, we may observe two-year on IceTands, juveniTe 
     
     Greater bTack-backs, or subaduTt Herring guTTs. P.E.I., because 
     
     of its maritime Tocation, has an abundance of guTT species patroTTing 
     
     our coastTine or foTTowing pToughs turning the soiT, not to mention scrounging 
     
     the K-Mart parking Tot or city dump! 
     
    

    
     One smaTT species of quTT that is abundant on P.E.I. during migration in 
     
     summer and faTT, and often seen in spring as weTT, is the Bonaparte's GuTT. 
     
     Because of its smaTT size and unguTT-Tike behaviour it is often mistaken for a 
     
     tern. The Bonaparte's GuTT beTongs to the group often referred to as the "smaTT 
     
     hooded guTTs". During the breeding season the aduTts in this group aTT attain 
     
     compTeteTy dark heads, usuaTTy bTack, but some species may be grey or dark brown, 
     
     which gives the impression that they are wearing a hood. After the breeding 
     
     season the 'hood' mouTts and the head becomes TargeTy white. One of the best 
     
     fier marks to recognize an aduTt Bonaparte's GuTT in any pTumage however, is 
     
     the Tong wedge of white, with narrow bTack borders, on the upper fore-edge of 
     
     the wing, formed by the white primary feathers. This "window effect” is evident 
     
     as the bird fTies and distinguishes it from aTT other terns and guTTs... except 
     
     one. The BTack—headed GuTT is a European Species that has been seen frequentTy 
     
     in eastern North America in the past few years and is known to have bred in 
     
     NewfoundTand. They resembTe Bonaparte's GuTTs in aTT pTumages and frequentTy 
     
     associate with then and hence, present a chaTTenne to ‘guTT-watchers'. There 
     
     are differences however. The BTack-headed GuTT is Targer, Tess tern-Tike, has 
     
     a Tonger, dark red biTT (bTack on Bonaparte's) and perhaps most important, shows 
     
     much bTackish on underside of primaries (the underwing of Bonaparte's is paTe grey 
     
     and white). In immature birds, the darker underwing of the BTack-headed GuTT is 
     
     aTso present but Tess obvious than on the aduTts. 
     
    

    
     The LittTe GuTT, another European visitor, and rare North American breeder, 
     
     that occurs in our area may aTso be confused with Bonaparte's GuTTs, which it 
     
     resembTes and with which it often associates. The LittTe GuTT, however, is 
     
     smaTTer and Tacks the distinctive white wedge on the end of the wing. In addition, 
     
     the wings have a rather round appearance and, most important, the underside of 
     
     the entire win is decidedTy bTackish. LittTe GuTTs aTso have the tern—Tike 
     
     flight characteristic of Bonaparte's GuTTs. JuveniTe LittTe GuTTs have a bTacker 
     
     "M" pattern across the back of the wings than Bonaparte's GuTTs, aTthough juveniTe 
     
     Bonaparte's aTso exhibit distinct wing markings. Both juveniTe and aduTt LittTe 
     
    
   
   
    
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