Subject: Eagles and Heron Nesting Disturbance?
Date: Jun 4 12:14:56 1996
From: Maureen Ellis - me2 at u.washington.edu



Folks,

I reported a few weeks ago that there appeared to be two active Great Blue
Heron nests in the Des Moines Washington Beach Park area. Actually there
were FOUR completed nests with adult occupants. According to a retired
couple who monitor the Des Moines Marina area frequently (as much as twice
a day! for many days successively), bald eagle harassment has caused a
failure of this small local rookery, at least for this season. My friends
said they actually witnessed an eagle attacking a nesting heron. An active
eagle nest is thought to be on the bluff side of Normandy Park just north
of the Marina. Can someone confirm that eagles are nesting there this season?

There appears to be an interesting sociobiological phenomenon
occuring here with regard to resource competition (is it space or food on
the local tideland or ???). Any chance that eagles and herons may be
natural enemies in the lion/hyena style? Do eagles routinely attack ANY
other large birds nesting relatively near them? There are still one or
two adult herons feeding in the Marina area; whether they are the
survivors is unknown. Commentary, please. Thanks,

Maureen E. Ellis me2 at u.washington.edu Univ of WA and Des Moines, WA