ML640395908

观察细节

Dark, medium-sized, tern-like bird that was sitting out on a green buoy straight out from the Boca Chica jetty (I viewed from the Isla Blanca jetty). I studied the bird for over an hour as it quite literally sat on the buoy. It never joined any of the flocks that were feeding offshore which led me to believe that it probably wasn’t a Black Tern. Apart from the noticeable size difference, there was no visible white near the vent on this bird. It was predominantly brown with primaries that were clearly darker. I believe this contrast also eliminates the rarer Black Noddy. Wing coverts also appeared paler as the sunlight shone on the bird. From my location, it was quite the challenge to pick out any white markings on the bird’s forehead, which leads me to believe this bird may be younger bird, but I’m not completely certain about that. A couple times, I was able to see its tail as it dragged sloppily; it had a broad shape to it, almost squared. Adding to that, the bird opened up its wings once and I confirmed that the underwing was completely dark, eliminating juvenile Sooty Tern.