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FAUNA: The Day Shift

by Mary Parker Sonis

Mary Parker Sonis

Evening time at the creek belongs to the barred owl. By 4:30 p.m., the barred owl has awakened from its afternoon rest and is generally perched low over the creek, actively hunting for crayfish and amphibians.

When the sun comes up, it is time for the day shift to take over, and the calls of the red-shouldered hawk can be heard echoing over the trails.

Bolin Creek is home to many red-shouldered hawks. It is an ideal habitat for this predator. We have all probably heard the very vocal kee-aw kee-aw call as we wandered the trails of Bolin Creek.

Last year, I spent a good amount of time monitoring three different nests along the edges of the creek. Red-shouldered hawks tend to use the same location year after year, and they are easy to locate because they are so very vocal.

Mary Parker Sonis

In February the courting begins. This hawk is a medium-sized buteo that can be identified from above by its deep rust-colored shoulder patch. In flight, you will notice its orange and white chest markings along with a black tail striped with narrow white bands. They are easy to observe because unlike the red-tailed hawk, which tends to remain high in the canopy, the red-shouldered hawk often perches on a low branch near the creek. From this low roost, it is ready to pounce on small rodents like voles or shrews, or, as I have observed countless times, the numerous snakes that live both in the creek and in the leaf litter along the banks of the creek. The hawks also frequently take frogs and lizards. Like the barred owl, a red-shouldered hawk will often linger on the ground and dig through the leaf litter hoping to stir up a small snake or salamander.

By April, the eggs of the red-shouldered hawk will have hatched. Clutch size is generally between three and five nestlings, and you might notice that there are often different-sized young in the nest. Some species of birds will not begin incubation until all the eggs have been laid; the red-shouldered hawk incubates immediately, as each egg is laid, which means that some of the young will hatch before others, giving them some advantage over their siblings as far as size and access to food is concerned.

Red-shouldered hawks often feast on frogs, lizards and snakes. Photo by Mary Parker Sonis

My favorite observation spot last year was at Wilson Park, where a pair of red-shouldered hawks nested near the picnic shelter. This very public location had its advantages and its drawbacks for the hawk pair. The shelter in spring is a very busy place, with endless picnics and birthday parties at all hours of the day. You could hear the tension level escalate for the hawks when a party gathered. Toddlers were wheeling clattery toys beneath the nest, and barbecue smoke was billowing into the air. The hawks were on edge. They flew over the shelter and called out to each other repeatedly. Sometimes the tension simply became too much, and a hawk would dive down and swoop some unsuspecting soul at the edge of the crowd. You may wonder what could possibly be the advantage for the hawks to build a nest in such a busy location.

The answer, of course, was right at the shelter. Barbecuing for a large number of guests makes for a crowded cook space, and occasionally a burger or chicken wing would drop off the grill, with the hawk in the air before the food hit the dirt. Wildlife will take advantage of whatever can be found, and the case of the hawks at the picnic shelter was not so different from the sightings of bears at trash dumpsters.

Locals were also used to discarding uneaten grill items onto the grass just to watch the hawks make their spectacular drops to the ground. It is often confusing to know when it is appropriate to feed wildlife. We are encouraged to put out birdfeeders for our songbirds but discouraged from feeding deer and bears, as it can endanger both the humans and the wildlife. In the case of the hawks, it is hard to determine whether our habits are interfering with the natural order of the forest or merely allowing a predator to do some ordinary scavenging to supplement its diet.

In the scenario of the hawks and the picnickers, the hawks made peace with the multiple intrusions into their nest territory and gained some advantage during nesting time, when food demands are very high. At more peaceful non-party hours, the hawks managed to bring in a regular supply of reptiles and amphibians to their young. It was interesting to me that snakes were by far the most predominant item on the menu.

Wildlife often makes strange alliances when there is a proven need. The case of the crow and the red-shouldered hawk is a prime example of this uncharacteristic cooperation. Most birds hate crows, which are egg stealers. They are also intelligent guardians of their territory. When I want to locate a great horned owl, I listen for the sound of the mobbing crows. As the most dangerous aerial predator of the forest, a great horned owl will bring complete cooperation from all other birds.

Mary Parker Sonis

In the midst of a crow mobbing, I have seen red-shouldered hawks calling out the kee-aw endlessly. I had thought that the crows were mobbing the hawk until I investigated further and found a well-camouflaged great horned owl at the center of all the excitement. The calling of the red-shouldered hawk was not distress over being mobbed; rather, he was simply joining the crows in driving away the owl. It is surely an uneasy alliance, as crows steal eggs, and hawks predate nesting crows. Stated in political terms, “the enemy of my enemy is my friend.”

In the case of the hawks at the picnic shelter, perhaps we are seeing another strange alliance. All the dropped food left behind by the human occupiers of the park is an attractant to rodents as well as hawks. The hawks occasionally swoop the guests and steal a bit of chicken, but they also keep the outdoor food area free of mice and rats. Sounds like a pretty fair deal to me.

Special thanks this month to Tom Giduz, a local birder and friend, who was the first person to locate the Wilson Park nest last spring.