While I’m always curious about the behavior of animals, my monitoring of birds breeding this spring has been sporadic for several reasons, leaving me with more questions than answers.
In May, my brother, Dana, came for a visit. One of my hosts at my current digs had invited us to stay at her house on a family farm in Highland County. Unfortunately, Dana couldn’t come when she and her husband would be there, so he and I ended up having the charming, spacious house all to ourselves for a few days (May 6-9).
I love Highland, but its nickname — Virginia’s “Little Switzerland” — is appropriate, with its high base elevation, higher ridges and a corresponding climate. The bottom of the hollow we were headed to is about 3,000 feet up. For comparison, the highest point on Skyline Drive, at Skylands, is 3,680 feet. Spring usually arrives in Highland a week or two behind Rappahannock, and when we arrived at the farm, it was cold and wet.
Fortunately, neither Dana, after his long trip from Alaska, nor I, still dealing with a bout of chronic bronchitis, felt like doing much. Rather than the hiking I had originally planned, we enjoyed spending most of the vacation talking, playing cribbage and observing nature comfortably from the large bay window in the living room. It offered a spectacular view of layers of forest leading up to a high ridge in the northwest, which was shrouded in mist most of the time. The verdant landscape was still beautiful, and the cushioned seats in the window accommodated both of us lounging there at the same time.
Our host had also alerted us to two Baltimore orioles who had regularly been visiting a mountain laurel outside a window in the kitchen. We found them there, quietly staring at us through the window. Orioles usually hang their basketlike nests high in a tree surrounded by open spaces, so this was the first experience I’d had with them up close, and I knew little about them.
One of the birds was bright orange and black, with white wingbars — a mature male. The other sported the same hues but more dilute and deferred to the mature male. Although they usually occupied the bush at the same time, they perched apart and rarely interacted. At first, I assumed they were a breeding pair, but if so, why weren’t they exhibiting courtship or nest-building behavior, which generally occurs in April-June?
Orioles are frugivores, so I had brought oranges to chum them in, although obviously they didn’t need any encouragement. When I went out to put a couple of halves in the laurel, the birds flew off temporarily. Glancing down in the bush, I was amazed to find a robin’s nest just a foot or two from where the orioles had been perching. It held two chicks that had most of their flight feathers, with just the last wisps of nestling down still ornamenting their heads.
Sneaking peeks of the robin nest from inside later, Dana and I saw the parents regularly bring food to the chicks, flying in low and seemingly unbothered by the orioles. In contacting our host, I found she knew about the nest, and she sent photos of the chicks she had taken a day or two after they hatched.
I decided to move the oranges to another mountain laurel around the corner of the house from the first, drawing the orioles away from the robin nest . . . for a while. But the next day, the orioles began tapping on the windows next to both laurels. There was plenty of orange left, but had the food triggered what appeared to be territorial displays? Were the orioles starting to guard the laurel, which produces berries later in the year? Were they just responding to their own reflections? Or was something else going on?
After reading up on the species, I figured out that these two orioles probably were not mates but rather two males, the paler one a juvenile. With bird species in which mature males have different coloration (usually brighter) than mature females, juvenile males can look similar to females. Figuring out why two males were hanging out together and what exactly they were doing will require more research.
According to Birds of the World (BOW), orioles usually arrive at breeding grounds in the following order: mature males, juvenile males a few days later, and females a week or so later — about the time my brother and I arrived, in this case. But I had yet to see any females in my brief walks outside.
When not watching the orioles, Dana and I spent a lot of time chillaxing in the bay window, watching other birds going about their business in the yard. A pair of bluebirds regularly brought food to one of five boxes on a bluebird trail there, obviously feeding chicks. I also noticed the male bluebird carrying away something white and realized it was a fecal pellet (aka fecal sac). With bluebirds, as explained by BOW, the arrival of an adult at the nest can trigger nestlings to present their rear ends and deliver these white, gelatinous pellets filled with their fecal matter. The adults carry each pellet away, dropping it more than 60 yards from the nest. I’d read about this method of nest sanitation but had never seen it in action.
On our last day in Highland, the sun finally broke through. Dana and I lingered at the farm, reveling in the added splendor the sunshine brought. Taking a walk up the farm lane, we heard a couple more oriole males but still saw no females. On our way back, we checked the active bluebird box, finding four chicks (possibly five) about halfway to fledging; our host reported seeing five eggs when she checked the box before we got there. The robin chicks, then about two weeks old, would likely leave the nest in the next day or two.
As I’m writing this (May 25) from Briar Ridge (see sidebar online for bird breeding notes here), my hosts are back in Highland, so far reporting that the bluebird chicks have also fledged, and apparently a pair of tree swallows were using another bluebird box on the trail. Orioles have been heard but not seen. They produce only one brood a year, so I hope they get started soon.
Birds breeding at Briar Ridge . . .
Early in the spring, I had noticed a bluebird pair courting — the male feeding the female — along the well-established bluebird trail here on Briar Ridge. Then for weeks, I saw a female coming and going from box four. For up to a half hour, she would hunt for food from perches a few yards away from the box, eating what she found and then going into the box for more than an hour. That indicated she was brooding her first clutch of eggs rather than feeding chicks. My hosts, who monitor the trail, reported finding five eggs in the box.
Females do all the brooding, so it was no surprise that I didn’t see the male during this period. Within a couple of weeks, in late April, the female started bringing food to the box, so the eggs had hatched. I also saw the male once briefly near the box.
When my brother and I returned from Highland County on May 9, I checked for activity on the bluebird trail again. Seeing none, I hoped that indicated that the brood in box 4 had fledged and not fallen prey to one of the many predators that raid such boxes. The next day, an adult male was chasing a female around box 1. Was this the same pair, with the female not ready to start her second clutch or having already bred? Or were these different birds? In any case, today I noticed that a pair of tree swallows had taken over box 4, and the bluebird pair finally settled on box 1, with the female now brooding her second clutch of eggs.
Scarlet tanagers, eastern wood pewees and many other migratory birds have also arrived at Briar Ridge to breed. I saw the tanagers courting today, the male feeding the female food. Two pairs of phoebes have already apparently finished with their first broods and Carolina wrens were noisily bringing smorgasbords of food crammed into their beaks to their fledglings. While Baltimore orioles and scarlet tanagers produce only one brood a year, robins, bluebirds, phoebes and wrens are among the many species in Virginia that typically have three broods, so this year’s breeding bonanza is far from over.
© 2022 Pam Owen