Coastal Species Spotlight: Black Guillemots

The predominant object of our daily attention here on Petit Manan is the tern colony, and with just under 2,000 nest sites this year they do keep us busy. But, in honor of the many other avian residents who call Petit Manan their breeding home, today we are very happy to honor the Black Guillemot. Maine is the tip of their southern range, so we are the only state in the lower forty-eight to host them.

We have noted over fifty Black Guillemot nests here on Petit Manan and some chicks have begun to hatch. Many mornings, during our twice daily lighthouse survey, we count more than 200 of them in the waters surrounding the island, paddling around with their bright red feet.

Guillemot eggs do not usually hatch at the same time. Even eggs in the same burrow may be a day or two apart. The chick that hatches first is referred to as the A chick and is typically larger and heavier than the B chick. As part of our routine on the Brother’s Islands, for instance, we check guillemot burrows every two to three days. As the chicks are now beginning to hatch we will be measuring their wing cords and taking their weight during our checks to monitor their growth. At the end of the season these measurements will help us to determine the guillemots’ productivity.

Our first A chick, Albert, weighed in at a whopping 63g! Our B chick, Bathalamue, came in at a slightly more modest 57g. In order to continue to tell the chicks apart in their burrow as they grow we must somehow mark either one or both of the chicks. At this stage a small dab of nail polish on the A chick’s down does the job quite nicely. Later on we may replace the nail polish with a more permanent metal band with an identification number around their leg so they can continue to be recognized in years to come.

Even though they are only a few days old Albert and Bathalamue have very distinctive personalities. Bathalamue is quite calm and lets us take our measurements without a fuss. Albert, on the other hand, is quite feisty and full of sass. From the moment we first pulled him out of the burrow he was a rage filled ball of fluff trying to snap at our fingers with his tiny black bill.

We found one new pair of chicks on June 27 and look forward to the next few weeks as still more will continue to hatch. We certainly appreciate our guillemots and we hope you do the same!