As the breeding season begins, we are watching two adult peregrines at the nest box on the Washington Mutual Tower in downtown Seattle. They are obviously a mated pair and thought to be the same birds from last year. However, without bands on their legs, we cannot be certain if they actually are the same individuals.
We are expecting the first egg to be laid at any time. Some of us are thinking that this spate of warm spring weather with sunshine happening this weekend might kick the female into producing her first egg of the season, but of course, that is totally up to her.
She appeared to be in "egg lethargy" yesterday, sleeping during the day, feathers fluffed out, walking around in the box, etc. but still no egg as yet today.
Ruth Taylor reports that three other established pairs of peregrines are already on eggs right now at other nest sites in Seattle so can the two WAMU falcons be far behind?
What usually happens is that a new pair will be later than normal in their first year, sometimes up to two weeks behind the norm. It takes them time to get to know one another, synchronize copulation with laying, work things out and essentially get together as a pair.
In their second year, the egg dates usually advance by a week or two but after that, laying generally takes place near the same date each spring, severe weather notwithstanding.
So at this time, all we can do is check the website several times a day in anticipation of egg production.
Keep in mind, however, that in some rare cases, one of the adults may be infertile. In these cases, courtship and incubation can still occur, but no young will be produced.
Finally, as some of you may remember from last year, the three eyasses (chicks) died early on from a bacterial infection at the nest box. We have consulted with Dr. Lindsay Oaks, veterinarian and raptor specialist at Washington State University, regarding another potential bacteria situation this year. He related that this type of organism is unlikely to survive and remain at the nest site over the winter and suggests that we need not worry about this eventuality.
However, just in case, we completely replaced the old nest box with an entirely new one (built and donated by Martin Muller) and placed onsite by Denise Kolb of Wright Runstad, the building managers at the tower. Thanks to them both and especially to Wright Runstad for their continuing support.
