Habitat Associations of Wintering Dabbling Ducks in the Arkansas Mississippi Alluvial ValleySubmitted by editor on 8 February 2021.
By John Herbert
The floodplain of the Mississippi River, the Mississippi Alluvial Valley (MAV), supports high densities of waterfowl during the winter months, which in turn attracts high numbers of waterfowl hunters. This region is typically considered the most important winter habitat for waterfowl in North America, and Arkansas makes up a large portion of the MAV. To monitor waterfowl populations in Arkansas, the Arkansas Game and Fish Commission conduct aerial surveys three to four times each winter to observe and estimate waterfowl populations. These surveys are critical to monitor these populations, set hunting regulations, inform hunters of the current conditions, and ensure management efforts designed to support waterfowl populations are effective.
The mallard (Anas platyrhyncos) is the most abundant waterfowl wintering in the MAV, so most hunting regulations and management decisions are based on the population status of the mallard. However, the mallard is just one of many species of dabbling ducks (ducks that forage at the water’s surface) that winter in Arkansas, but less is known about their habitat use and distributions. These dabbling duck species include, wood duck (Aix sponsa), gadwall (Mareca strepera), northern pintail (Anas acuta), American wigeon (M. Americana), northern shoveler (Spatula clypeata) and green-winged teal (Anas crecca). Dabbling ducks are mobile in the winter, moving among habitats to find available resources, avoid hunters or seek better weather conditions. Therefore, it is necessary to understand if any differences exist among mallards and dabbling ducks to better inform management decisions and conservation efforts.
In our paper, we analyzed seven years of aerial survey data to estimate the abundance and distributions of dabbling ducks in the Arkansas portion of the MAV. We were interested to see how weather and habitat type affected habitat choice, so we used land cover datasets and remotely sensed data to map the available habitat and surface water across the landscape. We also compared the results to a previous study that used mallard data during the same time period.
We found that habitat inundated with surface water, rice fields, soybean fields and open water (ponds, aquacultures) were the most often used habitat types by dabbling ducks. Throughout the study, we found that surface water and rice fields were key drivers for high abundances of dabbling ducks. Additionally, dabbling ducks would often seek warmer temperatures and avoided snow/ice. We found that dabbling ducks and mallards used the same habitat types and had similar distribution patterns. These results indicate the current hunting regulations and management set towards mallard populations is appropriate to use for other dabbling ducks. However, it will be important to continue waterfowl research on all dabbling duck species, especially at smaller spatial scales than we used in this study.