Eastern Bluebirds

In colder months finding Eastern Bluebirds seems to be feast or famine; either I won't see them at all, or I'll see 3-6 of them hanging out together. Given they look more gray than blue in my picture, I'm assuming these are females (though even the males can look gray in certain light).

A century ago, the Eastern Bluebird was considered to be in danger of extinction due to loss of nesting and loss of foraging habitat. That dire consequence is past us, though Eastern Bluebird populations are still suppressed due to competition for nesting locations for these cavity nesting (bird houses or hollow trees) birds. 

Apparently Eastern Bluebirds are one of the few bird species known to have had twins. Twins in birds implies that 2 birds hatch from the same egg. My suspicion is that twinning happens much more often than we know; in most cases the only way to tell is if we see N number of eggs but see N+1 number of hatchlings, and we just don't monitor every bird nest well enough to get data on this. Between domestic birds and bird-cams trained on eagle/hawk/owl nests though, it does seem like the phenomenon is pretty rare.

November 3, 2021 at Duke Farms
Photo 168431686, (c) jpviolette, some rights reserved (CC BY-NC)


Comments

Post a Comment

Popular posts from this blog

Tussock Moth Herd

Image
Some caterpillars are usually seen in large numbers (like Armyworm Moth caterpillars and Eastern Tent Caterpillars ), while most are more solitary. The Milkweed Tussock Moth caterpillars (more about them are here ) seem to be slightly social. I'll sometimes see them alone, but more often I'll see them in groups of 2-9 members. In the 1st picture below, you can see there is a clear size difference in some of these individuals. I'm almost certain the little one in the middle is in an earlier instar than the others (though they lack the colorful tufts of fuzz in their earliest instars). August 31, 2021 at Washington Valley Park Photo 167477945, (c) jpviolette, some rights reserved (CC BY-NC) In the picture below, it's clear that these caterpillars don't require a lot of personal space. August 31, 2021 at Washington Valley Park Photo 167477979, (c) jpviolette, some rights reserved (CC BY-NC)
Read more

Copper Underwing Caterpillar

Image
I believe this caterpillar to be a Copper Underwing [1]. At least the coloring and the dorsal hump (near the left end of the caterpillar) seem consistent with the Copper Underwing. These caterpillars are not what you'd consider picky eaters; my Caterpillars of Eastern North America describes their diet thusly: Many wooded plants including apple, basswood, blueberry, cherry chestnut, current, grape, greenbrier, hawthorn, hickory, lilac, maple, oak, poplar, raspberry, rhododendron, viburnum, Virginia creeper, and walnut. Wikipedia adds: Ash, privet, honeysuckle, rose, and service trees. That's a pretty wide range of trees and shrubs. One of the challenges of finding them is that they could be almost anywhere; the other challenges are: Their green coloring blends in pretty darned well with the average leaf. They have a habit of feeding underneath leaves, so they're probably not visible when looking down at their location. They have a tendency to move from leaf-to-leaf; if you
Read more

Eastern Pondhawks

Image
I'm going to try something different today with my Eastern Pondhawk pictures. I'm going to let ChatGPT do my blog today. (ChatGPT is an AI program that you can converse with in a pretty human way; an explanation of it is here .) Me:  Can you tell me something interesting about the Eastern Pondhawk? ChatGPT:  The Eastern Pondhawk (Erythemis simplicicollis) is a dragonfly species that is native to North America. It is a medium-sized dragonfly, with a wingspan of about 3 inches, and can be found in a variety of habitats, including wetlands, marshes, and ponds. One interesting characteristic of the Eastern Pondhawk is its mating behavior. Male Eastern Pondhawks are known for their territorial behavior and will defend their territory from other males. They will patrol their territory and will try to mate with any females that fly into their territory. Another interesting fact about the Eastern Pondhawk is that it is a fast flyer and is able to hover in midair. It is also an import
Read more