Influence of sanctuary disturbance, weather, and landscape characteristics on waterfowl harvest opportunity in western Tennessee

The North American Waterfowl Management Plan (NAWMP) recognizes waterfowl hunters and non-consumptive users as important stakeholders to sustain waterfowl populations through economic and political support for habitat conservation initiatives. Opportunities to shoot at and harvest ducks are key determinants of achievement-oriented hunt satisfaction and quality. Therefore, identifying factors influencing harvest opportunity would help hunters and wildlife managers identify optimal days afield and promote hunter recruitment, retention, and reactivation (R3) efforts in support of NAWMP. Waterfowl extensively use spatial sanctuaries during hunting seasons, especially diurnally, which could limit their perceived availability to hunters. Thus, a possible management action to support R3 is allowing limited public access on sanctuaries, which could offer diverse recreational opportunities for non-consumptive users and potentially increase harvest opportunities for hunters in traditional hunting areas if the limited disturbance caused waterfowl to leave sanctuaries. Therefore, we evaluated to what extent experimental sanctuary disturbance, landscape characteristics, and weather influenced local harvest opportunities. We conducted disturbance treatments including travel by a covered truck (i.e., truck with enclosed cab), a pedestrian on foot, and an uncovered vehicle (e.g., motor boat or all-terrain vehicle [ATV]). To measure harvest opportunity, we used autonomous recording units (ARU) to enumerate daily shotgun volleys at a landscape-scale across western Tennessee, USA, during 2019-2021 waterfowl hunting seasons. We identified 339,391 distinct shotgun volleys (x over bar $\bar{x}$ = 73 shotgun volleys/day/ARU). Shotgun volleys decreased 50% within 2 weeks of opening day and did not notably increase for the remainder of the hunting season. Contrary to our predictions, sanctuary disturbance decreased harvest opportunity. Specifically, the pedestrian disturbance and covered vehicle disturbance decreased daily shotgun volleys by 32% and 31%, respectively. Additionally, harvest opportunity decreased 20% with every 5-km increase in distance from a sanctuary. Harvest opportunity increased 2% for every 1 & DEG;C decrease from mean low temperatures and 9% with every 10-hPa increase in barometric pressure from the previous day. Conversely, harvest opportunity was unaffected by changes in cloud cover, daily precipitation, waterfowl abundance, or surface water inundation. Our results suggest disturbing sanctuaries decreases harvest opportunity and, in turn, may reduce hunt quality and satisfaction. If increasing harvest opportunity is a primary management objective, we recommend limiting sanctuary disturbance to maximize local harvest opportunities. Furthermore, greater harvest opportunity nearer sanctuaries indicates that additional disturbance-free areas may increase local harvest opportunities and hunter satisfaction.

Automated summary

The North American Waterfowl Management Plan recognizes the importance of waterfowl hunters and non-consumptive users in sustaining waterfowl populations. Identifying factors that influence harvest opportunity can help improve hunter recruitment and retention efforts. Disturbing sanctuaries can decrease harvest opportunity, and factors such as distance from sanctuaries, temperature, and barometric pressure can also affect harvest opportunities. Limiting sanctuary disturbance and creating disturbance-free areas near sanctuaries can increase local harvest opportunities and hunter satisfaction.