Early Birder Gets the Bird
Field Observations
This week, I decided to focus on birds since I had no classes on Friday which provided me an opportunity to go out in the early morning for some birding. I remember going out at 5:40 in the morning in my ornithology course in undergrad, but I was not able to bring myself to wake up quite that early. My morning outdoors began at 8 am, which is more like lunchtime for the birds who have been awake for as long as the sun has. I was struck by how the different my woods looked with the morning sun's rays glowing through the trees, and the mist hanging above the Kesling Wetland. It was 55 degrees F out but the sun made it quite pleasant but not too hot. The birds too, seemed to be enjoying this nice, cooler summer weather as they flew about from tree to tree, or over the prairies and fields. I heard so much more birdsong than my previous excursions later in the day. The morning belongs to the birds.
One male Goldfinch in particular kept flying over the rosinweed (a tall, yellow flowered plant) that bridges the border between the Wetland and Thomas Woods. When his wings would hit the downbeat I'd see the flash of his bright, yellow body and then his wings would beat upwards again obscuring my view. His calls were frequent but did not seem stressed. In the making of this blog, I learned that I had actually witnessed a courtship ritual. Some other bird sounds I heard included the presence of my familiar Eastern Pewee, who I was finally able to get a glimpse of when she perched on a branch in the tree next to me. I only ended up seeing a handful of birds since I am rusty at using binoculars and the foliage is so thick that it makes it quite difficult, especially since most of the birds seemed to stay in the upper canopy making it even more difficult to spot them so far away. The bright red male Cardinal at least stood out amongst the green leaves, and he seemed to stay in the mid canopy as well. One bird I got to see in a snag (dead tree) that was pretty far away from where I was standing looked like a Piliated Woodpecker. However, since it was so far away I am not positive in my ID, but it was a very large woodpecker and the call sounded similar enough. Some other calls I was able to identify included Tufted Titmouse (they sound like Peter, Peter), Catbird, and of course my Eastern Pewee. My two favorite sightings were the Indigo Bunting and Baltimore Oriole, two uniquely colored birds, the first blue and the latter orange and black. However, there were probably beautiful brown birds that I was unable to find due to their camouflage. We tend to focus on more easily identifiable and flashy animals as amateurs, but we must remember that all creatures great and small are unique and have value whether or not we find them aesthetically pleasing.
Species Identification
(note the photos in this section are all from Audubon and are cited below. I do not possess a camera to capture birds sadly)
Indigo Bunting (Passerina cyanea)
This beautiful blue bird can be recognized by the darker blue head, lighter blue body, and black and blue wings. The females are not blue, just brown, since they do most of the nest sitting and need to be camouflaged. Indigo Buntings are a bird species that prefers to live on wood edges or brushy pastures in rural areas. However, they do not do well in super urbanized areas or places with intense agriculture. These birds do not require large, unbroken forests which is why they are doing so well today compared to other birds. In fact, they are often the most abundant song bird in a particular area due to this. You can often find these birds along railways or powerlines as well as wood edges, particularly ones near streams. Nesting on the other hand, occurs typically on bushes, old fields, or low trees. Nests are typically between 1-3 feet off the ground. Females construct nests out of grass, leaves, bark, weeds, and other sorts of materials and lay 3-4 white or blueish-white eggs. The males claim their territories in the spring, defending it with their song, and often have several mates in their territory at the same time. These birds will eat insects, seeds, and berries depending on the season, and will forage on the ground or in the trees giving them access to plenty of food sources.
National Audubon Society. (2020). Indigo bunting. https://www.audubon.org/field-guide/bird/indigo-bunting
Baltimore Oriole (Icterus galbula)
The Baltimore Oriole is a bright, orange bird with black wings with a few white stripes. Sadly, populations are on the decline due to the Dutch elm disease which killed their preferred nesting tree, the American Elm. Baltimore Oriole habitats include groves alongside rivers, open woods, and shade trees with nesting in the open woods or edges of forests rather than the interior. Overwintering habitat is the tropics. You can find these orange birds anywhere east of the Great Plains. Their diet consists of insects, especially caterpillars even of species most birds won't touch, as well as nectar from flowers. They are also known to feed from sugar-water feeders set out by humans. Their courtship ritual entails the male standing in front of a female, and then bowing deeply with his tail spread and wings partly open. The female will then build a nest, sometimes with her mate's help, out of plant fibers, grapevines, grass, Spanish moss, bark, etc into the shape of a hanging pouch with the rim securely attached to a treebranch. The nests are usually 20-30' above the forest floor, and are constructed near the end of slender, drooping branches. The inside of Baltimore Oriole nests are lined with plant down, hairs, and tiny strips of grass. The eggs range from 4-5 typically and are a blue-white to light-gray with brown and black markings on one end.
National Audubon Society. (2020). Baltimore oriele. https://www.audubon.org/field-guide/bird/baltimore-oriele#
American Goldfinch (Spinus tristis)
National Audubon Society. (2020). American goldfinch. https://www.audubon.org/field-guide/bird/american-goldfinch#
Eastern Wood Pewee (Contopus virens)
This light brown bird with short tuft of feathers on its head and white throat has a simple beauty as well as a beautiful sound. You can hear a longing pee-a-wee typically before you can spot this small flycatcher. While they sing at both dawn and dusk, this song can often be heard late into the evening as well, being the last bird to sing before bed. These birds typically perch in the middle story of trees where they can then dart out to catch insects flying by. In the summer, their diet is made up of flies, wasps, bees, ants, beetles, moths, true bugs, and grasshoppers. Pewees will eat both bugs they catch in flight, or while hovering over plant foliage and grabbing the insects sitting there, as well as sometimes eating insects found on the ground. The Eastern Wood Pewee calls woodlands and groves home. They will live in decidious or mixed woods and rarely coniferous forests. They prefer living near clearings such as meadows, roadsides, ponds, wetlands, or small openings within the forest. They overwinter in similar habitats in the tropics. Not much is known about mating behavior. Females construct open cup nests out of plant fibers, cobwebs, and cover the outside with lichens. The nests can easily be mistaken for a bump or knot of the tree, usually deciduous on a horizontal branch, that the birds nest in. Pewees only lay 2-3 (rarely 4) eggs which are white with brown and lavender patches/spots which are more concentrated on the larger end.
Question of the Week
Q: Think about the transitions between your habitat and neighboring habitats. What are some of the ways these zones affect the plant and animal species in your habitat?
Since Thomas Woods is not very large, it is easy to walk around the trails on the outside fairly quickly and see all the different edge spaces and ecotones. For those who don't know, an ecotone is a biological term for where two different ecosystem communities meet and the space where that occurs. There can be a hard boundary between the two regions, or a soft gradual blending. Either way, these spaces are often high in diversity due to having topographical and vegetative heterogeneity!
Thomas Woods as seen across Kesling Wetland
In my Habitat, there are a couple of ecotones. One is that a wetland borders one side of Thomas Woods and all that separates the two visually is the path that runs alongside the wetland. Through my exploration of the woods, it does seem like tree and shrub species that prefer saturated soils grow on this side of Thomas Woods versus the other species that grow on the more elevated parts of the habitat. Some examples include young ash trees I have found as well as oaks. From my learnings about bird species this week, I know there are bird species, such as Indigo Buntings, who like living in forest edges that border wetlands or rivers/streams. This is an example of diverse life evolved to live in these unique combinations of habitats. I know that in spring time this section of the wetland floods which is when the borders between the woods and wetland become even more blurred, and there would be an exchange of nutrients. Other than birds, insects and amphibians would be more examples of species that would live in this edge space, with water providing larval or tadpole habitat and then the forest providing adult habitat.
Thomas Woods & WPP Edge and Thomas Woods and Merry Lea Farm Edge
Another space with an ecotone is the fields that begin on the edge of Thomas Woods where the farm is and on the opposite sides of the woods, the Woody Perennial Project field (WPP. This is a field where multiple woody crops are grown such as berries and occasionally cows eat grasses inbetween the rows). At the woods edge and the farm field's beginning, there would be a mix of tree seedlings and under the trees where there is still some light availability grows prairie and field plants you wouldn't normally find in a forest. This is also where species you do find in a forest but only on the edges occur as well, such as the Tall Bellflower from a few blogs ago. It is also the only place I have found the small Self Heal plant as well.
Many insectivorous bird species depend on the woods for nesting habitat and the surrounding fields as a food source with the various insects and grass seeds they can find there. I often see birds flying amongst the farm field or WPP, sometimes sitting on a fence pole, before hightailing it back into the trees when I come walking by. Insects such as butterflies also depend on these spaces as adults such as swallowtails depend on flowering plants for nectar sources but the caterpillars are often connected to a forest host plant such as a tree. Now that the farm field has been mown down, I'm sure birds will congregate more on the WPP fields which have not been mown, and are also surrounded by tree all around, providing lots of edge space for them. Birds of prey will also depend on these ecotones as well, often waiting on a tree until they spot an unsuspecting smaller bird or mouse in the field to pounce on.
Path Through Elevated Part of Thomas Woods
While not an ecotone because it is in the middle of the forest, something to help think about this concept is the forest paths that run through one side of Thomas Woods. Many flowering species are found along this edge space created in the middle of the woods because the canopy is a bit more opened up. The Tall Bellflower in particular likes to grow here under the trees as well as Bottle Brush Grass. This is sort of like a very small scale type of ecotone, just one caused by a disturbance, in this case a path.
Creative Response
Indigo Bunting by Jaime Reese
Media: watercolor and ink
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