足背 そくはい くろ かもめであれば
kisokuhaikurokamomedeareba

Noun
Da Copula

The "-eba" conditional form ("if/when…") of 黄足背黒鴎

1. If it were a yellow-footed gull with a black-backed gull:; If it is a yellow-footed gull with a black-backed gull:

Ba Conditional