Edward Soldaat wrote in on the last post to add some more useful notes on making the cormorant identification in last week’s Dead Bird Quiz. I didn’t want to just leave those buried as a comment, so I am pulling them up and featuring them here, front and center. Edward knows vastly more than I about skulls, so I present his comments as given:
“In addition: another important feature to distinguish cormorants from shearwaters or gulls is the absence of the depressions for the salt glands above the eyes. In this case skull and bill were too big for any shearwater, only a giant Cory’s Shearwater would have come close. But in smaller cormorants the lacking of visible nostrils and salt gland depressions are important characteristics. Interesting is also that cormorants and darters (not in gannets, pelicans or other) have a small dagger shaped bone connected to the back of the cranium, embedded in the strong musculature of the neck: the occipital style.”
The salt glands are organs you may have seen in action in living birds like gulls, which will occasionally tilt their beaks down as a clear liquid runs down from their nares. These are secretions from the glands, which function almost like an accessory set of kidneys, cleaning salts from the blood and allowing seabirds to drink saltwater and compensate for their actual kidneys’ comparative (to mammals) lack of ability to produce concentrated wastes.
The second item for your persual today is a flyer I worked up to address the many questions that nature centers, town officials, and biologists get from the public about birds sporting metal tags or orange cable ties. If you walk a beach for us, and know of an information board, a nature center, community center, public library or other spot where people might see one of these, would you consider printing and posting one for us? We might gain some new recruits, or, at the very least, alleviate some confusion among beach goers not in the know.