Yellowstone Reports

Summertime

Nesting in the Aspens
by Dan Hartman

July 12, 2017

I've been photographing birds in a dozen aspen groves this summer. What it really comes down to was the fact I didn't have a single owl nest for the first time in years so I had time to do something else. In all I located some two dozen cavities.

6 flicker, 5 bluebirds, 3 hairy woodpeckers, 2 red-naped sapsuckers, 1 williamson sapsucker and 1 three toed woodpecker.

The rest were tree swallow, wrens and nuthatches. Not all the nests were good for photographing, so I basically worked three areas.

The first aspen grove lined a small stream. There were only nine trees, four of which were dead. The areas between the aspens were littered with four to five feet tall aspen saplings. Circling the grove was a large sage brush flat.

I first checked out the trees from the highway using binoculars. Right away I spotted a small clean cut hole about golf ball size. It was in a live aspen and had a brown spot four inches below the cavity.

An active red-naped sapsucker nest.

How how would I know that?

The small size of the hole. The precision the perfect hole was drilled, almost like using an exacto knife. That told me it was a sapsucker. The fact it was in a live tree made it a red-naped instead of a williamson (they usually choose a dead or dying tree). And the brown spot below the hole is made by the birds tail as it brings food to the nest, showed me it's an active nest. (The brown (dirt from the woodpeckers tail) will wash off over the winter.

The next day I walked out to the little grove. I soon discovered a mountain bluebird was using an old cavity four feet below the sap-sucker's nest and thirty feet to the right in a dead aspen, just five feet off the ground was a flicker nest full of screaming chicks. More than an hour passed before the red-naped sapsucker flew in. He landed beside the cavity, waited while the female squirmed out then cimbed in with a beak full of ants. That told me the chicks are still quite small. Until they grow larger, an adult will always stay in the cavity after feeding until the other adult returns with food and they again make the switch. I noticed after they emerged from the cavity they flew down into the saplings before flying upslope to gather ants. When I investigated, I discovered a sapwell. This is a spot on a saplings trunk where the sapsucker has drilled a series of oblong holes to get the tree sap running. The birds will slurp up the sap before gathering ants. The chicks will then receive a nice rounded meal.

Over the next week I spent three mornings at the nest sites. On my second visit, a hunting badger trotted by. I soon noticed the male bluebird wasn't spending much time gathering insects. Instead he was obsessed with defending his nest area, dive bombing the sapsuckers and flickers whenever they delivered food and any other bids who happened by.

At the end of the week, the four flicker chicks fledged, relieving some of the bluebird tension.

Upslope a half mile (at the edge of an old burn), I checked out a mature aspen grove. There were thirty some live trees but only one held cavities. About ten feet up in an old flicker cavity a pair of bludbirds were raising a family. A couple of years ago that same cavity held a family of flying squirrels. Twenty feet higher was a flicker nest and just three feet above them but on the other side of the trunk housed another red-naped sapsucker family. Once again, the bluebird constantly harrassed his tree mates.

Out in the middle of the burn in a cluster of dead aspens I came across a hairy woodpeckers nest. The screaming chicks led me to another woodpeckers nest, this time a three-toed. While watching them, I noticed a flicker bringing food to another nest to my left. Also a bluebird pair was nesting just overhead.

Four more nests.

What's interesting about these nests is the proximity to the burnt trees. Woodpeckers and flickers were looking for ant and beetle larva which the dead and dying burnt trees provide.

Just behind me layed a large timber stand the fire spared. At times I could hear a bear ripping logs. Once a badger came within thirty feet of me. Soon the hairys fledged, then a few days later the flicker nest and the next morning, the three-toed jumped.

Photos

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