The thunder had passed but the wind remained, whipping in the darkness through the prairie grass, over the little hills and scattered oak trees to Brian Winter's field blind.
The retired ecologist waited for dawn. In the soft light, still muddled by storm clouds, Winter watched the grass of a ridge in front of him. Swans glided in a pond just beyond it. A hawk circled out in the distance over a vast western Minnesota prairie.
Winter looked worried.
