Effects of weather and landscape use on mourning dove population trends in North Dakota

Abstract

AbstractMourning dove (Zenaida macroura) populations are believed to be declining throughout much of the United States since widespread population surveys were implemented in the mid‐1960s. However, results from the Mourning Dove Call‐Count Survey and North American Breeding Bird Survey indicate no trend for mourning doves in North Dakota. In addition, little is known about how climate and landscape factors may influence trends in mourning dove populations, especially in the northern extent of their breeding range. We used late‐summer roadside counts conducted in North Dakota from 1970–2017 (n = 3,368), along with information from National Oceanic and Atmospheric Administration (NOAA) weather stations and the Census of Agriculture (United State Department of Agriculture) to develop generalized linear mixed models to analyze trends and identify weather and landscape variables that may be affecting mourning dove populations in North Dakota. Our results indicated that mourning doves counted along roadside transects have declined over the last 50 years in northcentral, northeast, and southeast regions of North Dakota where agriculture activity is most intensive and total cropland currently makes up at least 65% of the total landscape. Conversely, in northwest, southwest, and southcentral regions of North Dakota, where cropland makes up less than 50% of the landscape, we detected no trends in mourning doves counted during the same period. In our weather and landscape model, area of harvested corn and soybeans had a negative effect on mourning doves counted ( = −0.174, SE = 0.029, 95% CI = −0.232, −0.116), whereas area of woodland had a positive effect on mourning dove abundance ( = 0.137, SE = 0.053, 95% CI = 0.032, 0.241). In addition, we found no evidence that temperature or precipitation were influencing mourning dove populations in North Dakota. Woodland habitat steadily declined in North Dakota during our study period. Additionally, the amount of corn and soybeans planted throughout the state has increased rapidly over the last 20 years, which has decreased cropland diversity, and this pattern of land use change is likely reducing food and cover during the nesting season. To halt declining mourning dove populations in intensively farmed regions, managers should implement conservation programs and private land initiatives that aim to provide a more balanced mix of cropland, grassland, and woodland, with reductions in corn and soybean acres.