Kites of Southeastern North America

I judge the quality of my vacations based on how much wildlife I see.  The best time to view wildlife is early in the morning, but I’m saddled with a late-sleeping teenaged daughter.  I’ve given up even trying to get an early start.  However, at home in Augusta, Georgia, I’ve had better luck lately.  The other day I was jogging on the road in front of my house and thought I saw a pair of cuckoos flying but they went by too fast for me to make a positive ID.  Later that afternoon, I did hear the unmistakeable call of a cuckoo in the woods behind my house and have since heard them twice more. (http://www.allaboutbirds.org/guide/yellow-billed_cuckoo/sounds)  I believe the cuckoos are nesting there.  I hope they eat the hornworms that ravage my tomato plants, and the tent caterpillars that chew up my blueberry bushes.  Cuckoos eat caterpillars that other birds find distasteful. 

One morning, I saw a Cooper’s hawk fly directly toward my back window before veering away.  Red-tailed and red-shouldered hawks are common in my neighborhood, but this was the first Cooper’s hawk I have ever seen in Augusta and I have lived here for 37 years.  During summer, I almost always see Mississippi kites soaring high over me when I’m suffering through my morning jog.  I saw 6 along with a black vulture last Saturday.

Mississippi kite.  Usually, they soar so high, I can’t see their color pattern.

Mississippi kites (Ictinia mississippiensis) are summer residents of southeastern North America.  They winter in South America.  They prey on cold-blooded animals–large insects, frogs, lizards, and snakes.  Kites avoid freezing climates because their cold-blooded prey becomes inactive and unavailable.  Kites catch and eat cicadas and grasshoppers while they are flying…a kind of eat on the go attitude, like Americans eating hamburgers and French fries while they are driving their cars.

Swallow-tailed Kite Photo

Swallow-tailed kite.  I saw one of these once in Jenkins County, Georgia.  It was also soaring very high in the sky.

I’ve seen a swallow-tailed kite (Elanoides forfincatus) just once–in Jenkins County, Georgia.  They were formerly common, spending summers as far north as Minnesota.  Like Mississippi kites, they winter in South America.  Swallow-tailed kites were known for eating the insects and reptiles fleeing ahead of the annual fires that burned through pine savannahs.  Up until well into the 20th century, it was popular for people to shoot birds for the hell of it, and these callous hicks devastated swallow-tailed kite populations.  Swallow-tailed kites have been completely eliminated in North America outside of the south, and they are considered rare within this region.

Image of Snail Kite

The snail kite is a South American bird that ranges into south Florida.

The snail kite (Rostrahumus sociabilis) eats nothing but snails.  It lives in south Florida and central and South America and does not migrate.  In Florida the snail kite feeds upon apple snails.  It seizes the snail with its talons, then waits patiently for the snail’s head to emerge from the shell.  It quickly grabs the snail’s head with its beak and tears the body loose.  Snail kites are increasing in number, thanks to an abundance of invasive snails.  Snail kite populations have doubled in the 10 years since the Island apple snail, a South American native, escaped from aquariums.  In 2010 a scientist from the University of Florida published a stupid study claiming the introduction of the Island apple snail would cause the snail kite to become extinct in Florida within 30 years.  The author of this study suggested the kites would expend too much energy trying to exploit the larger snail.  However, snail kites in South America thrive on this snail, and the author of this  study saw his illogical conclusion debunked by the facts immediately. Most invasive species are considered destructive, but the introduction of the Island apple snail is a case of a beneficial invasion.  Besides snail kites, limpkins, another snail-eating bird, have increased in the past few years. Island apple snails even eat invasive hydrilla, a plant that clogs waterways all across the south.  Before the Island apple snail invasion, wildlife officials were afraid the Florida population of snail kite was headed for extirpation. 

adult

The white-tailed kite has a curious distribution, living in south Florida, south Texas, Mexico, Central America, and the Pacific coast.

White-tailed kites (Elanus leucaras) were absent from Florida between 1930-1985.  Hunters had eliminated this population.  But they have since recolonized Florida.  This kite has a curious distribution, living year round in south Florida, south Texas, Mexico, Central America, and the Pacific coast.  At some point during the Pleistocene, this bird probably had a continuous range.  The white-tailed kite is a species that requires prairie habitat.  During some climatic phases, a grassland corridor connected the eastern and western populations, but the area in between has since become forested.  In this respect it is similar to many other species such as the burrowing owl, scrub jay, brown-headed nuthatch, and diamondback rattlesnake that have separated eastern and western populations.

Kites are absent from the fossil record of southeastern North America, but undoubtedly they’ve lived here for millions of years.  Kites just happen to live in environments where they are not likely to become preserved.  They avoid caves and rarely die in a river–the 2 processes most likely to preserve them.  Fossil evidence of Mississippi kites has been found in northern Mexico.  Genetic evidence suggests different migratory populations of Mississippi kites diverged early during the Pleistocene and have not interbred since.  They’ve been spending summers in what’s now known as Georgia since before Homo sapiens existed as a species.

Advertisements

Tags: , , , , , , ,

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s


%d bloggers like this: