[Tweeters] Mountain nesting Great Blue Herons in the Olympics
bboek at olympus.net
Mon Jun 17 21:43:05 PDT 2013
In mid-May, Charlie Miller, a resident of Port Angeles, was hiking on the Heather Park trail in Olympic National Park. This trail climbs up a steep north-facing slope above the ONP Hurricane Ridge entrance station, in a dense forest of big second-growth Douglas-firs, hemlocks, and occasional cedars and silver firs. At about a mile up the trail, at approximately 2800 feet elevation, Charlie heard some strange screeching in the forest by a small creek that becomes a tributary of Ennis Creek. Looking more closely, he discovered that the sounds were coming from a couple big nests high up in some Doug-firs.
Not sure what was in the nests, Charlie contacted Hank Warren, retired chief naturalist of ONP. Charlie, Hank, and Hank's wife Raedell, returned to the site and discovered that the nests had Great Blue Herons with half-grown chicks in them.
This afternoon, 6/17, I got to join Hank and Charlie at the site. There are at least 3 nests -- one nest with 2 large mostly-feathered chicks, and two nests with 1 mostly-feathered chick each. Two of the nests are in one tall Douglas-fir, at least 100 feet above the ground. The other nest is in another tall Doug-fir about 50 m away, also about 100 feet above the ground. While we were there, the biggest chicks were trampolining, jumping up and down on the limbs flapping their wings. The smaller chicks just stood in the nests. The parents were away, other than one adult that returned to the nest for a feeding, causing raucous begging by the chicks. The dense forest near the nest sites is on a very steep hillside. We didn't want to disturb the chicks, so we didn't go underneath the nest trees to look for debris and spilled food -- maybe after they fledge.
Looking at maps, these nests are about six miles from the closest salt water and at about 2800 ft elevation. The nearest standing water is at Lake Dawn, about 1 mile downhill as the heron flies, but it's a small lake mostly surrounded by homes. Could it possibly provide adequate food for growing heron chicks? Other than that, there are likely a few very small ponds around Port Angeles that may be planted with trout or carp, but again, I wonder if they provide enough food for chicks. The small creek that flows near the nesting trees is a marginal food source -- it's in a dense forest and likely has some amphibians but few fish. Our guess is the adults are flying long distances to salt water to find food.
I see from the WA Breeding Bird Atlas that GBH have been known to nest in Cascade river valleys up to middle elevations, like at Ross Lake (1600 ft elevation). But these ONP nests seem really out there, far away from water in a dense montane forest. There are no other nesting herons nearby in Clallam Co (at least that we know about!). The closest nesting colony is probably at Beacon Hill Park in Victoria BC. It makes me wonder if this is what nesting herons must now do to avoid Bald Eagle harassment closer to salt water. How many others are out there in similar situations?
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