Tuesday, October 30, 2007

The Rhythm of a Symbiotic Relationship

Driving along a county road, sweeping across the sky above a field is a flock of gulls. Just as gulls were more rarely seen in urban areas forty years ago, so also were they rare in rural areas far from large bodies of water.

As the Killdeer and other grassland birds become more and more rare the gulls have moved into to occupy their niche. And that niche is to be the benefactors of the feast exposed as the farmer turns over the soil. And in turn the birds deposit rich organic matter to help fertilize the fields for next years crops.

Notice the several runs have been made from one side of the field to the other discing the dirt. Look carefully. The gulls are grouped along the far edge of raw earth, working the furrows of the latest run.

The gulls at the far end of the field have taken to the air displaced by the oncoming farmer.

The flock who had been working the fresh area, wheels round. And just as in the case of the gulls foraging in the wet parkland for worms, there are separate groups working in turns.
There is already a group just standing in the unworked area on the far side of the field.

The gulls fly to the far edge. Some land and some from the ground take flight.

The farmer and tractor rumble their way nearer.
And like steps in a dance, each group knows what the other is doing as they also take into account the pattern of the tractors movement. Gulls glide over the tractor and behind it to grab the invertebrates before they have a chance of wiggling back into the loosened earth.

And there on the far side of the field, is the group of gulls...resting ? Waiting their turn?

The tractor turns and the dance continues.

Foot by foot the gulls peel out of the way in steady rhythm.

They fly back over the tractor once again and begin the ribbon of gulls from the earth to the air to the earth again in the other direction.

And for whatever reason a new grouping spot of gulls has begun in the next field over which looks to have been disced earliecr in the day.
The waiting group in the old position is still in place but perhaps are a different set of birds. The gulls in the furrows feed and forage, aware, alert, and waiting for the next turn in the dance.
Donegal Browne

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