For 20 years, Julia Parrish of the University of Washington has been studying seabirds on the Pacific Northwest coast. During this time, the population of Bald Eagles has rebounded. What does the growing eagle population mean for Common Murres? When an eagle flies over a nesting area of murres, the murres leave the island for the safety of the water. Females leave their eggs behind, and gulls come and eat the eggs. But the murres have started to innovate, to nest in places that eagles - and gulls - can't get to.
Common Murres and Bald Eagles: The Work of Dr. Julia Parrish
Interview by Todd Peterson
This is BirdNote.
[Calls of colony of nesting Common Murres]
For 20 years, Julia Parrish of the University of Washington has been studying seabirds on the Pacific Northwest coast. During this time, the population of Bald Eagles has rebounded, with their protection by the Endangered Species Act and the banning of DDT. Dr. Parrish tells us what a growing eagle population means for the Common Murres of Tatoush Island.
[Calls of a Bald Eagle]
Track 175; 3:00 – …every time an eagle flies over a nesting area of murres early in the season...the murres leave the island for the safety of the water…Every time … a few females who have laid eggs end up leaving their eggs behind. And when they do that, gulls come in to chow down on the eggs. So the number of eagles in the system basically facilitates predation by gulls. This happened to the point where the gulls were able to eat all of the murre eggs that were produced over the early season… I would say that the murres on Tatoush were really in trouble. This turned out to be a microcosm of what is happening right now all along the North Pacific coastline, particularly in Washington and Oregon and we think even down into Northern California.
So why aren’t the murres there now extinct? What are they doing differently? Well, they’ve started to innovate, to nest in places that eagles, and gulls, can’t get to.
Track 175; 6:17 – We think of murres as nesting on rocky outcroppings and vertical cliff walls. But murres in the Pacific Northwest actually nest under canopy vegetation, including Salmonberry and salal. That allows murre colonies to survive…
You’ll find more about Julia Parrish’s work on our website, birdnote.org.
Sounds of provided by The Macaulay Library of Natural Sounds at the Cornell Lab of Ornithology, Ithaca, New York. Recorded by
Producer: John Kessler
Executive Producer: Chris Peterson
© 2011 Tune In to Nature.org November 2011 Narrator: Michael Stein