By Randy Meidinger
Goebel Ranch Manager
The duck nest research at DU's Goebel Ranch in South Dakota is winding down, and we’re beginning a busy season of duck banding. Wetland conditions are good at Goebel, with lots of brood water and plenty of broods occupying the wetlands. This is quite a refreshing change after seven years of dry conditions in the area. There still are a hand full of birds sitting on nests, in fact we just flushed a pintail off her nest just yesterday – these late setters better hope for a late winter if they want their offspring to make the flight south!!
This year we ramped up our grazing/nesting study on Goebel to include more acres searched to increase our duck nest sample size. We found nearly 1200 duck nests this year on about 4750 acres; that’s a nest for every 4 acres searched. For comparison, during 2008 we found 226 nests on 2825 acres; that’s a nest for every 12.5 acres searched….what a difference a little water on the prairie makes! This year bluewings and shovelers made up 56% of the nests found (compared to 23% the past 3 years), while Gadwall and Mallards made up 24% of the nests (compared to 54% the past 3 years), and we found a pretty consistent percent of pintail nests over the course of the past 4 years, ~16%. It’s interesting to note the flip-flop in composition of nests between bluewings and shovelers vs. gadwalls and mallards in comparably dry years vs this wet year at Goebel.
Overall apparent nest success is looking pretty good at 31%, but certain species fared better than others: Pintails led the way with 44%, followed by bluewings and shovelers at 33%, with mallards having 26% success, gadwall didn’t do nearly as well at 19%, and scaup brought up the rear at 12%.
We also had a higher than usual number of hens killed by predators on their nests this year. However, due to this mortality we did discover a good number of the local nesting hen population is wearing leg bands that were placed on the birds in previous years at Goebel. I believe we found 6 banded hens that were killed by predators and also saw a good number of banded live hens during our nest revisit efforts.