Saturday, January 20, 2007

No wintry mix

The storms are raging all around us. The same thing happened last week when most of Missouri was clobbered with terrible ice storms and southeast Missouri saw nothing worse than drizzly skies. Weather patterns in southeast Missouri are unlike any I've seen before. Last spring brought terrible wind storms and tornadoes, the summer was as bad as a New Orleans summer, and this fall brought almost record-breaking rainfall. Funny thing, when the rest of the county is doused with bad weather, where I am, situated between the Mississippi River and a small patch of forest, I don't see the worst of it.

Missouri's midcontinental location makes it the focal point for all kinds of weather. The "character of air" over Missouri is determined by the source: warm, humid air comes up from the Gulf of Mexico. Dry, cool air comes out of the southwest. Warm, dry air comes over the Rockies. Blasts of frigid air comes from Canada. Air masses from different regions usually stick around for 2 days before another air mass muscles in. The mercurial weather is something Missourians joke about: If you don't like the weather, wait ten minutes and it will change. There's some vague truth to it.

The county has seen a lot of rain in the past few months. Fields are flooded, the swamp is full, the bayou is full. With all the standing water in the area, the air mass above the county is cooler and more humid than normal. The storm that's raging all around us is breaking up when it hits this cool air mass. On the radar map it looks like we have a forcefield: red, yellow and green splotches everywhere but here.

Several years ago, climatologists learned that forests actually produce rain and influence weather patterns. The cooling of the air above forests causes disturbance and ultimately, rain. When the land around forests has been drastically altered, like it has been in southeast Missouri, the overall cooling effect of the forest is lessened but causes locally heavy downpours. It is estimated that tree-covered land returns to the air 10 times as much moisture as a barren area and twice as much as as areas with shrubs, grass or crops. This has a dramatic effect on weather patterns, as evidenced by the clear skies, again, tonight.

Thursday, January 18, 2007

Half a million snows

When wildlife agents determine that a species should not be hunted or collected in order to save it from inevitable demise, it's a big deal. 30 years ago, duck hunters weren't allowed to kill wood ducks because their populations were so small. Wood ducks have rebounded so handily that now there isn't enough breeding habitat to accomodate the population. Two years ago, over 50 sterile eggs were found in a single nestbox. The population is doing fine for now, but with the continued destruction of freshwater wetlands, their population might not be as stable in 20 years.

In 1916, snow goose hunting was outlawed because of a dramatic drop in their population. With the conversion of land to agriculture after World War II, snow goose populations increased so drastically (due to substantial winter food sources) that hunting was allowed again in 1975. Snow geese migrate from the Arctic tundra through the Midwest to the Gulf Coast, feeding on flooded grain fields along the way. In recent years, with thousands of acres of crop residue left in midwestern fields, the birds are "shortstopping," staying in the Midwest rather than making a full migration. When these populations return to their breeding grounds, full from the unlimited food supply, they have an increased ability for reproduction and are, in short, destroying their breeding grounds. In 2001, 1/3 of snow goose breeding habitat had been converted to salt plains and mudflats by overgrazing. Another third is greatly degraded and is being restored by wetland managers. The last patch of habitat is not so badly damaged, yet. With snow goose populations estimated at 6 million birds, that last third of the nesting habitat must be fiercely defended if any is to remain viable.

The population boom might be headed for a crash. With less food available for the hatchlings in the breeding grounds, the young birds starve to death or are too weak to make the annual migration south. Since the breeding grounds are so badly degraded, females are taking the young further away from the breeding grounds to raise them, areas with food that isn't as nourishing for the young.

Hunting hasn't made a dent in the population. Some states don't have a limit on how many snow geese hunters can kill (in Missouri and Louisiana, it's 20/day) and the season on snows increases almost every year. Hunters find it difficult to hunt the birds when they are in such large flocks. Apparently, you have to sneak up the flock to shoot one but if you scare one, you scare the whole flock away. To attract the geese to a certain field, you have to wake up really early and set out hundreds of decoys and then wait for the flock to find them.

On any given afternoon, 500,000 snow geese can be seen on a single field or pond in southeast Missouri. Around sunset, their calling (more of a "whounk" than a Canada goose "honk")can be heard for miles as they make their way to Reelfoot Lake for the night. With all the rain in the past few weeks, almost every field is flooded and at some point during the week hosts thousands of these large gregarious birds. People stop their trucks in the middle of the road to watch them settle in for a landing. This is probably the only time of year when the regular gunshots don't unnerve me.