Understanding How Agricultural Intensification Impacts Ring-Necked Pheasant Distribution and Survival in Eastern South Dakota

Historically, pheasants (Phasianus colchicus) have thrived in South Dakota in conjunction with successful land retirement programs or early farming practices through the 1950s, which created interspersions of agriculture and native landscapes that were ideal for pheasants. Recently, the Prairie Pothole ecosystem has undergone rapid agroeconomic expansion, effectively reducing ideal interspersions of native prairie and cropland into agriculturally homogeneous landscapes. Indices of pheasant abundance have suggested persistent population declines since 2008, raising concerns regarding landscape suitability. Our goal was to understand how agriculture intensification impacts pheasant ecology. The objectives were to: 1) estimate overwinter hen probability of survival, resource selection, and mortality risks associated with landscape features; 2) determine pheasant abundance as a function of remotely derived landscape composition and vegetative phenology; and 3) implement low-cost Arduino GPS trackers into our ring-necked pheasant study to improve fine-scale data collection. To accomplish these goals, we captured, collared, and tracked 100 female pheasants annually from December through March in each of three years (2016–2019). Overall, we captured 321 females and recorded 110 mortalities. We implemented low-cost GPS trackers on 35 individuals, resulting in 407 VHF locations and 1,574 GPS locations. This was a 287% increase in data density at only 23% increase in cost. We modeled weekly probability of survival and Cox proportional-hazard cause-specific mortality rates associated with landscape features. To understand pheasant distribution, we surveyed for and modeled pheasant abundance and distribution seasonally as a function of landscape composition and intraannual differences in vegetation phenology. Overwinter survival of pheasants (0.66) was highly influenced by snow depth. Pheasants using harvested fields experienced a 421% increase in risk of raptor predation. Additionally, pheasants using emergent wetlands experienced a 58% lower risk of weather mortality. Our distribution model demonstrated that proportion of Conservation Reserve Program grasslands, dormant wetlands, and 30- 40% row-crop agriculture within 1.6 km2 positively influenced pheasant abundance. Alternatively, pheasants were negatively associated with proportion of forests. Agricultural intensification is projected to continue reducing valuable concealment, grassland, and emergent wetland landscapes. As native perennial vegetation is critical to both pheasant abundance and winter survival, large-scale conservation efforts are critical to pheasant population viability. Innovative conservation solutions supplementing current farm bill policies may improve conservation adoption thereby improving pheasant abundance and overwinter survival