Wednesday, July 10, 2013

Birds of a feather


Looking out on the deck yesterday morning I saw a little gray lump that hadn't been there a few minutes before.  In spite of the grumpy look on its face, it just sat there unconcerned with my presence as I took its first baby pictures.  I could hear a scolding bird calling incessantly in the tree above but could never get a look at it.
"Get out of my face!"

I retreated inside and when I looked out ten minutes later it was gone.  I assume that it had made its maiden voyage from the nest and was resting up for another try.  Since many baby birds look the same at that age, I guess I will never know what species it was. 

A short video from the Missouri Department of Conservation is filled with "Awww, how cute!" moments as it explains the different habitats that birds raise their chicks in.  Many birds nest in isolation, selecting territory where there is less competition.  Black vultures manage to raise chicks on a bare ground floor of our barn.  The bluebird boxes are now hosting second broods and a wren has taken over a hanging flower box just off our deck.

Purple martins have one of the more unique methods of nesting.  They are communal cavity nesters, formerly selecting dead trees with multiple woodpecker cavities.  When the first settlers came along, they harvested dead standing trees preferentially, a rapid source of dry firewood for heating and cooking.  Fortunately, the martins were becoming adapted to and adopted by humans.  Soon they became dependent on us and today they only nest in human supplied housing.*

Purple martin chicks
There are now nesting purple martins in their special house above the lake at Close Memorial Gardens.  Since the houses are tended to by Charley Burwick, cleaning out nesting attempts by other birds, we have a chance to see the young chicks.  If you stroll the lake with your cell phone you can hear more about purple martins, or you can read the script here, as written by Katie Steinoff and Charley Burwick.  The Butterfly Festival on July 20th will be a good time for a visit.

Today's News-Leader article describes how Native American's started adopting purple martins by hanging hollowed gourds in their villages before the arrival of European settlers.  They may have functioned as scarecrows as well as a natural form of a "bug zapper".  Either way, the purple martins became comfortable with humans, a fact that helped them survive in communal nests as the forests started to be depleted.

Mounted specimen- Wikimedia
Another communal cavity nesting species did not adapt to humans, nor we to it, and it rapidly became extinct.  The Carolina parakeet, North America's only native parrot disappeared by 1920.  It had covered the forests in large loud and colorful flocks of up to 400 birds.

Their habit of flocking together may have protected them from most predators.  They were probably poisonous from eating toxic cockleburs (Xanthium strumarium) as Audubon noted that cats apparently died from eating the birds. Feasting together on the fruits of the forest and returning to their nests together, life was good.  Then a wave of humans crossed the landscape.
"Outside of the breeding season the parakeet formed large, noisy flocks that fed on cultivated fruit, tore apart apples to get at the seeds, and ate corn and other grain crops. It was therefore considered a serious agricultural pest and was slaughtered in huge numbers by wrathful farmers. This killing, combined with forest destruction throughout the bird's range, and hunting for its bright feathers to be used in the millinery trade, caused the Carolina Parakeet to begin declining in the 1800s. The bird was rarely reported outside Florida after 1860, and was considered extinct by the 1920s."  allaboutbirds.com
Multiple factors led to the extinction of Carolina parakeets, but many feel that the habitat loss of standing dead trees with hollow nesting sites was a major factor.  In addition to the harvest of timber, they faced competition from the advancing wave of European honeybees which accompanied and even preceded the settlers.

Carolina parakeet flocks were extremely noisy, making it unlikely that anyone would have wanted to provide nearby nesting habitat.  Like our Monarch butterflies, being poisonous wasn't enough protection from the environmental changes brought about by humans.  Whether we know it or not, we pick the winners and losers.

So what are we losing when a species disappears.  Francis Skalicky of MDC shared with me this 1877 account by Gert Goebel, a German immigrant to Franklin County***
"Until the later thirties (1830s) great flocks of paroquets came into our region every fall and frequently remained till the following spring.  They were a small variety, about the size of a dove.  They were bright green in color, and their heads were orange colored.  These flocks of paroquets were a real ornament to the trees stripped of their foliage in the winter.  The sight was particularly attractive, when such a flock of several hundred had settled on a big sycamore, when the bright green color of the birds was in such marked contrast with the white bark of the trees, and when the sun shone brightly upon these inhavited tree tops the many yellow heads looked like so many candles.
This sight always reminded me vividly of a kind of Christmas tree which was used by the poorer families in my native Germany."
Our threatened regal fritillary and swamp metalmark butterflies may not be a noticeable as the "paroquets" but some of us would miss them if they were gone.

*    The full purple martin story is at purplemartin.org
**  More extensive information on Carolina parakeets is on Wikipedia.
***  The Carolina Parakeet of Pioneer Missouri

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