Mute Swan 



Cygnus olor 



SI (introduced) 

 ---W 



Greater White-fronted Goose 



Anser albifrons 



-w 



— w 



--H 



Snow Goose 



Chen caerulescens 



MM 



-w 



--WW — WW-- 

 --WW-W 



t t 

 tttttttttttt 



Li_ii L i L 



t t 

 tttttttttt-t 



t t t t 

 tttttttttt- 



t 



t t t - t t t t - 

 t t 



Ross' Goose 



C/7en rossii 



t 

 tttttt-tt-t 

 t_ ^_t _t 



t t 

 t - t t t t 



t 

 t t - t - - t - - t - 



t - t 



16 



