Ground survey started in Eastern Dakotas

Written by Pam Garrettson
Friday, May 08, 2009

Pam Garrettson.We’re getting started with our survey today, about 3 days later than average. John Solberg, the pilot biologist for this crew area, delayed the start a few days because spring was late. The survey should begin once the early nesting species (in this area, that’s mallards and pintails) are well into nesting, and the mid- to late-nesters are on territories or even beginning to nest. To ensure that this happens, John and his observer make reconnaissance flights and note the pairing status of the local birds. While females are on the nest, males sit alone or in small groups on nearby ponds. So when you begin observing many birds as lone males rather than as male-female pairs, that’s an indication that species has begun nesting. Females spend more time on the nest each day as they move further into laying (a typical clutch is 8-12 eggs) and incubation, and that is reflected in the number of lone males seen.

Our job is to try to count every single duck and goose along our survey segment. Since we are on the ground, we can walk around and through wetland areas if needed to identify birds hiding in cover. The pilot biologist and his observer fly over the same segment (before we go in) and also count everything they can see. By comparing our numbers to their numbers, we can develop a visual correction factor, which is then used to “correct” the aerial survey numbers across the entire area that our pilot biologist flies. In southeastern South Dakota, conditions are drier, and we are seeing fewer ducks than I expected, but we have a long way to go.

On airground segment south of Watertown, SD 2009.  Left to right: Dan Collins, Pam Garrettson, Kammie Kruse, Rob Holbrook, Sam Gibbs.  Photo by Samantha Gibbs.

Pam Garrettson walking wetland, southeastern South Dakota, 2009.  Photo by Kammie Kruse.