75th annual spring breeding duck survey showed an index of nearly 3.4 million birds
NORTH DAKOTA – For wildlife science and surveys, the longer the history and added data for a population index create a similar growth in confidence in those numbers.
The longer we’ve done the survey, a similar confidence is gained for biologists and wildlife managers.
We’re not comparing a census count of every individual. The index is comparing numbers from past counts, in past years over time. This allows utilizing trend data to look at a population maintenance, loss or growth. Then comparing habitat and other factors and conditions, we are able to see a bigger overall picture of the species’ status.
The North Dakota Game and Fish Department’s 75th annual spring breeding duck survey conducted in May showed an index of nearly 3.4 million birds, up 16% from last year. Migratory game bird supervisor Mike Szymanski said the index was the 23rd highest on record and stands 38% above the long-term (1948-2021) average.
Indices for most individual species, with the exception of green-winged teal, gadwall, wigeon and blue-winged teal, increased from 2021. Mallards were up 58% from 2021 and represented the 25th highest count on record. The ruddy duck index increased 157%, shovelers and pintails increased 126% and 108%, respectively, and other increases ranged from 4% for scaup to 69% for canvasbacks. Decreases from the 2021 index were observed for green-winged teal (-42%), gadwall (-36%), wigeon (-10%) and blue-winged teal (-4%).
“It’s important to note that some of our statewide increases in species counts might not reflect broader-scale population trends, especially for pintails,” Szymanski said. “The abnormally wet conditions in the state are likely holding a higher percentage of breeding pintails than normal. We’re coming off a very dry year that resulted in low reproduction, range-wide, for many species.”
The number of temporary and seasonal wetlands was substantially higher than last year, as figures show the spring water index is up 616%, the largest single year increase on record for the survey. The water index is based on basins with water and does not necessarily represent the amount of water contained in wetlands or the type of wetlands represented. Consistent precipitation and cool weather leading up to the survey left a lot of water on the landscape in ditches and intermittent streams.
“Besides being our 75th consecutive survey year, this was an interesting survey, as we’ve gone back and forth between wet and dry conditions over the past couple of years,” Szymanski said. “We actually had our second highest wetland index in the state, which is largely made up of water that’ll dry up fairly quickly. But ponds that are important for brood-rearing habitat have rebounded nicely as well.
“A lot can change between May and hunting season, so we'll get a few more looks from our July brood index and our September wetland count,” he added. “But duck production should be a little bit better this year than it was last year due to a stronger breeding effort. However, we continue to lose grass in upland nesting sites that will diminish reproductive potential for ducks in the state. Despite expected low Canada goose production this year due to the harsh conditions in April, we did have a record number of geese on breeding territories, so hunting opportunities for those birds should be pretty good again this year.”