Owl watching and color morphs
Answers to readers' questions about the ethics of watching owls and red and gray screech-owls
Published: October 22, 2010
I’m concerned about an
owl that’s attracting birders and photographers to a nearby park. How
can you tell if all the attention is stressing the owl? Where’s the
line between responsible and irresponsible birding? — Sam Simmons, Pittsburgh, Pennsylvania|
One of the tenets of the American Birding Association’s Code of Birding Ethics
is: “To avoid stressing birds or exposing them to danger, exercise
restraint and caution during observation, photography, sound recording,
or filming.” I doubt anybody would argue with this principle, but as
you indicate, determining what is stressful to a bird is not always
easy, nor does everybody agree on how to define “restraint and
Owls are often at the center of this dilemma because
even common species are not encountered in viewable situations
frequently, and birdwatchers are anxious to see them. I have observed
people pruning vines near a roosting Northern Saw-whet Owl for clearer
photos and bushwhacking through dense vegetation to get a better look
at a winter roost of Long-eared Owls, even though the birds were
visible from a nearby trail.
Such actions can have consequences
for owls. People flushing or disturbing an owl may inadvertently draw a
predator’s attention to it — either directly or by alerting songbirds.
Small birds often mob owls, creating a commotion with their harassment
that can notify predators of an owl’s presence. In the winter, when
many uncommon owl species tend to be found, an owl’s energy budget must
be managed carefully. Every time an owl is flushed, or even if it needs
to remain awake and vigilant due to activity around it, precious energy
may be wasted.
Remember that when we find northern owls in
winter, it often means that they were driven south by a lack of prey.
The owls may be under stress to begin with, and now they must find
adequate hunting areas and cope with power lines, traffic, and other
hazards that may be limited in the birds’ usual boreal haunts.
much attention is too much? The level of disturbance an owl will
tolerate varies among species, individuals, and conditions. The bird’s
welfare certainly trumps whatever pleasure we obtain from watching it.
Keep at a distance. Never disturb or awaken a sleeping owl or interfere
with its hunting. If an owl watches you, it is probably assessing you
as a threat, so back away or leave.
It usually isn’t obvious
when an owl is under stress. I had an experience a few winters ago when
a Snowy Owl visited a local shopping center, attracting a lot of
attention. Some spectators spoke out about people making close
approaches. Others discounted any harm. One photographer claimed that
his observations led him to believe the owl was in good health and
exploring its surroundings, perhaps even “playing.”
was seen for a week, then disappeared. The following spring, the body
of the owl was found near the last location it was seen alive. I gave
the carcass to the state for a necropsy. The bird had no fat and had
died of malnutrition. It was an example of a bird that dozens of people
perceived to be healthy and “happy,” even as it was slowly starving to
I don’t find a lot of screech-owls, but the ones I have observed are gray. I have seen photos of “red phase” screech-owls. Are they rare or found only in certain places? Can owls change color? — Marshall Camp, Columbus, Ohio
The term phase implies a temporary situation, but screech-owls remain the same color for their entire life. The different color types are more properly called morphs. Species in a variety of bird orders worldwide have color morphs, but the plumage variations are found in less than four percent of all species. Owls have one of the greatest incidences of polymorphic species.
Eastern Screech-Owls come in two color morphs, gray and rufous (red). Brownish birds of intermediate appearance may be seen, but it’s unclear whether they represent a third morph, since at least some instances are due to fading, wear, or staining of the feathers of gray or rufous birds. The different color morphs are not related to age, the two types will mate, and both colors can occur in the same brood of siblings. Across the species’ North American range, about three-quarters of owls are gray, but the proportion varies geographically.
For example, the feathers of rufous-morph owls are more susceptible to wear. Thus, rufous morphs are less common in arid regions prone to abrasive dust — at the western edge of their range, fewer than 15 percent of Eastern Screech-Owls are rufous. Since rufous-morph owls also have higher energy demands, it is thought that the reddish feathers may be less insulating than gray feathers. Therefore, rufous morphs are less common in the cold climates of northern latitudes. Rufous-morph owls are more common, however, in humid, rainy, and cloudy areas, since the reddish feathers are harder to see in low light.
The genes that control plumage color are not linked to the bird’s sex, but rufous-morph females are slightly more common, probably because they are a bit larger than males and may be able to retain heat or body fat more efficiently.
Color morphs are also present in Western and Whiskered Screech-Owls and Flammulated Owls, although the various colors are less well defined.