I had three little visitors last evening as I sat on the patio eating dinner and enjoying the unusually mild August summer night. While I call them visitors, actually they are natives returning home as they had recently hatched in a hanging basket, overflowing with an asparagus fern, dangling under an eave not far from where I sat.
The three tiny Carolina Wrens continue to stay close to each other after having left their nest only about a week ago. It was funny watching them hop-fly from fence post to wire trellis and into the midst of a different hanging basket than that which they were born – one full of somewhat dried Dahlberg daises and red verbena. (Dried daisies because it is August, after all!)
The tiny wrens chattered non-stop while they ran around deep inside the hanging basket, popping their heads up through the straw-like foliage now and then. It appeared they were playing chase with one another, but perhaps since they were born and raised inside a coconut-lined hanging basket they have developed an affinity for them.
I had thought when I first saw the parent wrens jumping in and out of my asparagus fern a few months ago that they were chasing the moths and other insects I often see fly out of the baskets when watering them. I did not realize the birds were instead seeking out a nesting place and I had no idea a nest had eventually been built. It wasn't until I witnessed the parent wrens taking turns bringing worms into the fern that I understood a nest was present. You see, when I watered the fern, it did not disturb the eggs or nestlings because the parent wrens had built their typical "cup", or covered, nest. I have since learned that Carolina Wrens prefer to make their nests in cavities and containers and aren't too shy about nesting near human activity. A friend of mine consistently has broods of Carolina Wrens in her hollowed-out birdhouse gourds. My sister has had wrens hatch in a decorative box situated on a high shelf just outside her back door. However, in open containers, such as my asparagus fern hanging basket, the birds will usually construct a dome-like nest to "create a cavity" for added protection.
Above is an amazingly clear photo I was able to capture with my cell phone of the fledglings about a day before they left the nest. Don’t fret, I did not remove the hanging basket from its post, nor did I stick my head in the fern, nor did I dig around in the fern looking for the nest. I waited patiently for the parents to leave and then I simply reached up, placed my phone near the edge of the basket and, whoa-la – I captured an incredible pic . If you look closely, you can see the nest is "cupped" around the birds.
Speaking of chasing moths, wrens are classified in general as carnivores. I know what you are thinking – I, too, think of lions and tigers when I hear the word carnivore, but many birds and other less threatening animals are considered carnivores or “meat-eaters” as well. Actually, you can break the diet of carnivorous birds down a bit further and differentiate between those that primarily eat fish (piscivores) and those that primarily eat insects (insectivores). Wrens are insectivores and as such, they eat spiders, caterpillars, moths, crickets, grasshoppers, and roaches among other insects. They have been known to eat very small lizards and snakes too - more like a carnivore, I’d say! And, as you can see by my (rather blurry) photo below, you can indeed find wrens at your bird feeder but usually only when you’ve placed out a mix that includes berries or fruit. Although seed isn't typically a part of their diet, wrens do enjoy a bit of fruit pulp now and then.
Carolina Wrens are quite brave for their size. This one has no problem sharing the bird feeder with a squirrel. Blue jays and doves, much larger birds, usually stand by and wait for the squirrels to leave.
Like doves, blue jays, herons, etc., there are also several species of wrens. In my area of North Texas I predominately see the Carolina Wren and have come to learn its habits through direct observation. In researching wrens in general, I have discovered most have the same or very similar characteristics as the Carolina:
Small – 4 to 5.5 inches
Muted in color – browns, rusts and grays
Prefer the warmer climes of their range
No noticeable difference in appearance per sex or age
Sings and chatters loudly - especially in relation to their size!
Very active – doesn’t stay in one place for long
Performs short flights from one perch to another
Hops while on the ground
And, probably the most endearing and identifiable trait – they hold their tails upright (see intro photo)
While wrens share the majority of the above traits, there are a few distinct differences amongst the varieties, surprisingly, in relation to their mating and parenting behaviors. The sexes of some wrens share jointly in nest building and in the feeding and caring of their young while other varieties have separate responsibilities. Some wren species mate for life (such as the Carolina Wren), while others (such as the House Wren) will actually steal the favor of a female right out from under another male who has already built a nest for her – the new couple using the other male’s nest to bring up their chicks. Unfortunately this rogue-like behavior continues with House Wrens forcefully occupying the completed nests of non-wren species – destroying any "foreign" eggs already there. Very diverse stances amongst wren species relating to mating, no doubt!
Well, although the House Wren may be the most aggressive of the wrens, it is also amongst the most ingenious. To eradicate its nest of mites, that almost always plague hatchlings, the House Wren will add a spider egg sac when building, or taking over, a nest. The spiderlings eventually hatch and eat mites to their fill, leaving the newly hatched chicks healthy and parasite free. Thereafter, any lingering, well-fed spiders will most likely become a meal for the growing birds - an interestingly parasitic, symbiotic, and "circle of life" type relationship between mites, spiders and birds.
In conclusion, despite the sometimes unpleasant mating activities of the House Wren, it remains beneficial to welcome wrens of all types into your landscape – especially if you are a gardener. These small, energetic birds will adorn your foliage with cuteness and charm, fill the air with passionate song, and rid your space of pesky insects!
Until next time,