Hi Tweets,
Here's a recent item from the King County web page in regard to monitoring
of local herons.

Kevin Li
King County Environmental Lab
322 West Ewing St.
Seattle, WA 98119


March 30, 2000

Citizens Needed to Monitor Declining Heron Populations

Last April when Renton resident, and heron advocate, Suzanne Krom visited
the heron colony at Black River she was met with total silence rather than
the cacophony of squawking she'd heard only two weeks earlier.

This was a frequent scenario last year as herons, normally seen in abundance
from spring to mid-summer throughout Puget Sound, abandoned about 40 percent
of their nesting colonies in mid-season. This spring King County is asking
people to help monitor heron activity.

"The herons are an environmental indicator," says Dr. Kate Stenberg, Manager
of King County's Wildlife Program. "If the herons are disappearing then that
should tell us that something may be wrong in their environment," she says.

The Great Blue Heron is a colonial nester, which means they create large
colonies of nests in several locations. King County colonies typically
accommodate up to 100 birds, with numbers reaching 600 elsewhere in the
region. Normally they return to the same colony every year in January or
early February to begin mating and do not disperse until the end of July.
But lately they have not been returning to their colonies the following
year.

Though biologists began noticing this growing trend approximately five years
ago they have been unable to determine the cause. The identification of a
decline in Puget Sound heron populations is currently based on data
collected through individual colony monitoring. However, there has been no
systematic monitoring of the entire region.

"The King County Wildlife Program monitors colonies, but we need increased
community involvement to enhance our existing data," says Stenberg. "If you
live near a heron colony, we'd like to know what you saw last year and what
is going on this year. How many nests are there and when were they
occupied," she says.

The increased population of the bald eagle, a natural predator of the heron,
may be a factor. The eagles may prey on heron eggs and chicks and, once the
nest is exposed, it also creates an opportunistic situation for crows,
another bird population that is increasing in urban areas. Urbanization has
created a lack of heron habitat resulting in smaller nesting colonies.
Colony abandonment during the nesting season may be due to a decline in food
supplies, such as small fish and amphibians, for the herons.

Some of the larger local colonies are at the Kenmore Park & Ride lot; the
Black River, near the Renton Treatment Plant; Peasley Canyon, near SR 18 and
SR 167; and Lake Sammamish State Park, visible best from a boat out on the
water. People should stay at least 600 feet from a colony; an observer is
too close if the birds fly off their nests. Binoculars or a spotting scope
are best for observing herons from a distance.

To monitor a colony this spring, or for more information, contact Kate
Stenberg, Wildlife Program Manager, 201 S. Jackson, Suite 600, Seattle, WA
98104, call 206-296-7266 or e-mail kate.stenberg at metrokc.gov. Information is
also available on the King County Web site at
http://dnr.metrokc.gov/wlr/LANDS/wildlife.htm.