From the Contact Station August 2021

Swallowing and Swallows

To start, we have a July observation of an American Kestrel around #13. You may recall a banded Kestrel discussed here a couple months ago. This is a different, unbanded female.  About a week after the grasses were cut for hay on Swartz Field, we spotted this Kestrel with a nice tidbit (sorry for the ick factor).  That seems like an awfully big lunch.  We can only hope it was going to go back to a nest to share.

Thinking about swallowing something big, that brought to mind the challenge of knowing our swallows.  They come in the spring and stay through the fall, avoiding, with very rare exception, the winter.  Their specialty is eating insects on the wing.  The one exception is the Tree Swallow which feeds on berries in migration and winter; something we are not too likely to see on the refuge given their timing and that of any suitable berries. Swallow distribution in breeding season is based more on where they nest than what they eat.  They prefer open areas and, mostly, they will be found in proximity to water. Something to do with flying bugs, I am sure.

There are eighty-six currently recognized species in the swallow family, Hirundinidae, worldwide. On the refuge we can find seven species representing six genera. To find and identify the first of these species, I like to scan the hanging gourds to the right of the bridge as I enter the refuge.  They are easiest to find first thing in the morning when they are starting to emerge from the gourds.  Purple Martins historically used woodpecker holes for nesting, but the proliferation of human supplied “condos” has changed their habits.   Our largest swallow, the adult male is dark-bellied and the back is glossy blue-black.  The female can be confused with other swallows because they are pale below. But they can be distinguished by their large size and the pale brownish or grayish collar and generally dingy underparts.

As you round the bend to the straightaway toward the hunt gate, you are in prime swallow territory.  These fast flyers are zipping across the road and over the open water making them so hard to follow.  I like to focus my binoculars at a moderate distance. Too far away and I cannot get all the right features; too close and I cannot keep them in my binoculars.  One advantage on this part of the drive is they often like to sit on the chains that cross the closed area tracks. If you can stop a short distance from sitting birds, you can get a good view and not disturb them.

Photographer Angie Vogel had three species on one chain recently.  Easiest to start with is the Barn Swallow.  Beautiful dark blue back and that gorgeous rusty underside.  Cap that off with the deeply forked tail and you have the Barn Swallow. The female is less glossy with shorter outer tail feathers and the juveniles even less so but distinctly Barn Swallow nevertheless.  Originally a cave nester, the most abundant swallow in the world makes use of building eaves and bridges.  Every year we can find mud nests inside and outside the blind overlooking Rest Lake.  Quietly stand in the blind and, if you are lucky, a parent will come in to feed a nestling while you are there.

In abundance, you will find Cliff Swallows along the first leg of the road.  Two things pop out for me for good identification of this species.  If you are lucky enough to get a head-on view, or even a good angle on a side view, the Cliff Swallow looks like it has headlights.  The cream or white patch between the eyes really stands out.  The hues of colors are similar to the Barn Swallow, but the very light belly really gives a different look.  And, if it flies low enough or banks for you, there is a distinct pale buffy rump followed by a square tail.  The Cliff Swallow, a cliff and natural overhang nester, has also adapted well to bridges and culverts with its mud nests.  Watch for them to fly around the new entry bridge.  If you ever kayak down Lake River, see how many nests are under the bridge.

A little bit harder to separate on the wing are the Violet-green and Tree Swallows. They are bright white below and dark on the back.  They are both in the genus Tachycineta.  What I look for here is the pattern of white on the face and the rump.  As seen in the photo, the white reaches up around the back of the eye and over the top.  Similarly, the white reaches up the sides partway onto the rump, looking a bit like an upside-down saddle.  The Violet-green has a spectacular green back and head with some dark violet on the back of the neck and upper tail but my best sightings of these wonderful colors have not been on the wing but birds sitting in the sun.  It is a view that catches your breath. Also, the Violet-green is rather stubby looking due to a short tail.  As to nest sites, Violet-greens seem to be pretty open in their choices and will find cavities in trees or cliffs, use boxes, or reuse old Cliff and Bank Swallow nests.

On the Tree Swallow, the white color on the head stays below the eye.  In a side view in flight the white does not wrap up around the rump.  The blue color certainly looks distinct from the Violet-green but since blue is more a matter of light reflecting off feathers, not pigment, it can be quite different in quality depending on what the sun brings that day.  To be a bit more confusing, the female is variable in her plumage being not a steely blue as the darker male and sometimes reflects some green.  Juveniles, which we will be getting to soon, can be particularly challenging with a sootier gray on top and not so bright white on the bottom. Tree Swallows are all over the refuge, but since they readily nest in Ash tree cavities, they are easily seen flying around the woods beyond the Kiwa trailhead.

Less common than the previously mentioned swallows are the Northern Rough-winged Swallow and the Bank Swallow. The Northern Rough-winged Swallow just looks dirty to me.  The small (12.5 to 14.5 cm), square-tailed swallow is grayish-brown above and pretty much dusted everywhere else with a smattering of dull to creamy white in areas below.   By contrast, the diminutive (12 cm) Bank Swallow, also brown on the back, has dark wingtips and a bright white clean looking belly and throat. To distinguish it further, it has a notable contrasting brown breast band. Both of these species nest in burrows, though Northern Rough-winged uses burrows dug my other birds, Bank Swallows do excavate theirs.

Farther along the auto tour, good spots to look for swallows are between #6 and #7 over Ruddy Lake (now, it is more like Ruddy Field) and as you circle around Rest Lake between #11, 12, and 13.  With the dry weather, we are having this year, the lakes are drying to streams.  It is a win/lose situation.  I don’t come home with a bunch of mosquito bites, but the swallows seem to be fewer, maybe because their food is not so abundant.  And who knows if the heat dome had a detrimental effect on nesting.  All of our swallows have been confirmed as nesters on the refuge. The two Tree Swallow chicks were looking good two weeks post-heat dome. We can hope all will be well.

To close out this month’s column I have another photo from Angie that I could not resist.   What do you think the Cliff Swallow is saying to the Barn Swallow?  “I don’t care if it is outside, it’s six feet.”

Oops!:  We always work hard to obtain permission and give credit where credit is due on photos, but because of a mix-up on who took which photo, the Crane photos for July’s publication were mistakenly both credited to Anne Myer.  She did indeed take the photo of the family of three cranes, but not the first photo of the adult and colt.  With apologies, we are still trying to track down the other photographer.

-Susan Setterberg, Contact Station Volunteer