February 28 notes: nest building

For the last two weeks (since about Valentines Day) this pair of eagles has been sprucing up their home! The web cam provided a unique vantage point to watch this rarely-observed behavior. Check out the archived still photos during this period to observe bald eagle housekeeping.

Nearly every morning both eagles were busy carrying branches to the nest. The female (larger eagle) seems to be the interior decorator and spent the most time arranging the sticks. After two weeks of persistent work, they raised the nest platform about 6 inches. In the last few days, they began carrying small twigs and grass to line the nest bowl. Curiously, nearly all eagle nests contain a sprig of white pine in the nest bowl. We think this is nature's remedy to deter parasites like feather mites.

I've observed bald eagles on the ground in February gathering grass for their nest - an odd behavior for a regal bird that spends much of its time soaring high above the earth. I've also observed eagles snapping large branches from pine snags while in flight and oftened wondered, "what happens if the branch doesn't break?" They seem to have an uncanny ability to judge which branches will snap easily!

Bald eagles are the most sensitive to human disturbance at the final stages of nest building and just prior to egg-laying. Activity close to the nest can result in nest abandonment. - Mark McCollough, U.S. Fish and Wildlife Service