Backyard Naturalist: Annual Raptor Count Is Taken on ‘Great Circle’

Russ Mohney

Editor’s Note: Outdoors Writer Russ Mohney died Aug. 31. The loss is staggering. His writing and insight into the outdoors of Southwest Washington was unmatched. We will be publishing his popular column each week in the coming months from his abundant body of work created throughout the past decade for The Chronicle. This column was originally published Dec. 24, 2004.

Every year about this time I try to take a trip I call the “great circle,” which gives me a chance to gauge the relative population of local raptors. If I take that drive three or four times during the winter, I get a pretty accurate picture of the number of birds of prey we have.

The first leg of my annual winter journey is along either Airport Road or Scheuber Road to count the hawks living cheek-by-jowl with the cities. Pickin’s are usually good near those roadways and the population is generally strong.

The usual route continues on state Route 6 up the Chehalis and down the Willapa from the Twin Cities to Raymond, then north on U.S. 101 to the Montesano cutoff, and from there up the Chehalis Valley to the Twin Cities. On the last leg, I include the Brady Loop road, Wenzel Slough and the South Bank Road to Oakville.

The whole circuit takes from four to six hours — depending on how often I stop to identify a particular hawk or if I dawdle over my lunch — and is one of those little yearly departures that I thoroughly enjoy.

The value of the great circle is that it includes the richest habitat in our area for hawks, owls and eagles. It gives me a chance to actually count the birds I see along the roads, woodlots and farm fields by species — and those numbers can tell a lot about the natural state of affairs in our extended back yard.

I recently decided to devote a day to the trip out of alarm more than anything else. I was busy with a lot of other things, but several successive trips out Airport Road were troubling me. During the weeks since early November, I had not seen so much as a single red-tailed hawk or kestrel along that roadway. As a rule, I can count on finding from a couple to as many as six or more hawks and falcons there. This year, I didn’t even see any northern harriers, which are almost always cruising over the airport fields.

As a rule, the total count on the great circle route is from 30 to 50 hawks and other raptors, with the average being around 40 birds. The weather can be a factor, but the results are still usually within those parameters.

This year, the total was just eight — based on a single sample outing — and nearly all of those were between Porter and Montesano along the Chehalis River.

I don’t believe anything has occurred that would upset the general health of the habitat for birds of prey here in Southwest Washington.

Instead, we are seeing one of the many natural and wonderful cycles that take place within virtually every wildlife population.

These marvelous cycles most often represent the relationship between a collection of animals and their food resource. When food is abundant, the population burgeons; when food is scarce, there is a drop in reproduction and an increase in natural attrition. The population eventually balances itself with respect to the available food resource.

When the numbers of raptors are high we know that the population of rodents upon which they depend are also high. As hawks or owls eat more of the little mice and voles and squirrels — they need at least one each day — the abundance falls. As a consequence, the number of hawks the area can support also falls, and there are fewer to see and count.

With a reduced number of hawks around, the families of squirrels and mice begin to grow exponentially until they are discovered by another generation of hawks, and the cycle starts over.

We appear to be at the bottom of a completely natural population cycle this winter, but don’t worry. Soon the population of furry little rodents will rebound, and the hawks and owls will soon follow. Funny thing is, the system always seems to work.

Ain’t nature grand?

Russ Mohney, a fourth-generation Lewis County outdoorsman, expanded the best of his decade’s worth of “Backyard Naturalist” columns into a book. Copies of “A Simple Song: Recollections from a Backwoods County” are available for $12.99 at Book ‘n’ Brush, the Lewis County Historical Museum and at The Chronicle.