January 16, 2012

Occupy the Platte: we are the 1%

A flock of approximately 1,200 sandhill cranes occupies a soybean field in south-central Nebraska.  Fed up with
governmental policies that demand they fly extraordinarily long distances to migrate, these cranes (actually,
a bit fewer than 1% of the population which migrates through Nebraska each spring) are 'taking it to the man'
by waiting for spring (photo by Kelly Powell).
There is an intriguing event happening this winter on the Platte River in central Nebraska. Approximately 3000 sandhill cranes are still in Nebraska, having stopped during the fall migration.  Their colleagues (the rest of the 450,000 or so sandhills that migrate through Nebraska) went on to more southerly, traditional latitudes.

I spoke to an employee of Rowe Sanctuary, this morning, who wonders if these cranes first migrated south, found the effects of the 2011 drought to be unsatisfactory, and traveled back north.

Normally, Nebraska sees cranes in the spring when they stop to refuel on their way northward. Corn eaten from the Platte River Valley provides insurance when they arrive on the breeding grounds in Canada--in case they arrive to frozen conditions. But, Nebraska rarely sees the cranes for very long on fall migration.

The question worth asking is: are we seeing the first of a new pattern caused by high food resources (corn) in the Platte River Valley, teamed with a mild winter? Or, is this indeed reflecting the southern drought of the past year.  Long-term forecasters suggest that we may see another year of La Nina, which caused the 2011 drought--will we see the same migratory dynamics next fall and winter?

Of course, a large, blinding blizzard could remind these 3000 cranes why their brethren continued (or stayed) south. But, a mild winter could give these cranes an advantage, come spring, when they are positioned to arrive on the breeding grounds in good condition before their competitors. Time will tell, but it is a story worth watching over the next few years.

1 comment:

  1. This is most interesting. The weather has certainly been disrupted for the past two years. In my area, the Arkansas Delta of the Mississippi River, I have been noticing migratory birds well out of their normal range.