Doug Leier: North Dakota’s spring breeding duck survey provides insights into population trends

For wildlife science and surveys, the longer the historical past and added information for a inhabitants index create an identical progress in confidence in these numbers. The longer we’ve carried out the survey, an identical confidence is gained for biologists and wildlife managers.

We’re not evaluating a census depend of each particular person. The index is evaluating numbers from previous counts, in previous years over time. This enables using development information to have a look at a inhabitants upkeep, loss or progress. Then evaluating habitat and different components and situations, we’re capable of see a much bigger general image of the species’ standing.

The North Dakota Sport and Fish Division’s 75^th annual spring breeding duck survey performed in Could confirmed an index of almost 3.4 million birds, up 16% from final 12 months.

Migratory sport fowl supervisor Mike Szymanski mentioned the index was the 23^rd highest on file and stands 38% above the long-term (1948-2021) common. Indices for many particular person species, aside from green-winged teal, gadwall, wigeon and blue-winged teal, elevated from 2021.

Mallards had been up 58% from 2021 and represented the twenty fifth highest depend on file. The ruddy duck index elevated 157%, shovelers and pintails elevated 126% and 108%, respectively, and different will increase ranged from 4% for scaup to 69% for canvasbacks. Decreases from the 2021 index had been noticed for green-winged teal (-42%), gadwall (-36%), wigeon (-10%) and blue-winged teal (-4%).

“It’s vital to notice that a few of our statewide will increase in species counts may not replicate broader-scale inhabitants tendencies, particularly for pintails,” Szymanski mentioned. “The abnormally moist situations within the state are possible holding a better proportion of breeding pintails than regular. We’re coming off a really dry 12 months that resulted in low copy, range-wide, for a lot of species.”

The variety of non permanent and seasonal wetlands was considerably greater than final 12 months, as figures present the spring water index is up 616%, the biggest single 12 months improve on file for the survey.

The water index is predicated on basins with water and doesn’t essentially symbolize the quantity of water contained in wetlands or the kind of wetlands represented. Constant precipitation and funky climate main as much as the survey left lots of water on the panorama in ditches and intermittent streams.

“Apart from being our 75^th consecutive survey 12 months, this was an fascinating survey, as we’ve gone backwards and forwards between moist and dry situations over the previous couple of years,” Szymanski mentioned. “We really had our second highest wetland index within the state, which is essentially made up of water that’ll dry up pretty shortly. However ponds which can be vital for brood-rearing habitat have rebounded properly as properly.

“Loads can change between Could and searching season, so we’ll get a number of extra appears from our July brood index and our September wetland depend,” he added. “However duck manufacturing needs to be a bit bit higher this 12 months than it was final 12 months resulting from a stronger breeding effort. Nevertheless, we proceed to lose grass in upland nesting websites that may diminish reproductive potential for geese within the state. Regardless of anticipated low Canada goose manufacturing this 12 months because of the harsh situations in April, we did have a file variety of geese on breeding territories, so searching alternatives for these birds needs to be fairly good once more this 12 months.”