Data from: Regulation of body reserves in a hunted wader: implications for cold-weather shooting restrictions

1.Severe winter weather can reduce avian energetic reserves. At such times, reducing disturbance, and therefore energy expenditure, through science-based policy is crucial to mitigating negative impacts on survival.

2.We examined through allometric equations the energy reserves of Eurasian woodcock Scolopax rusticola, a popular quarry species across most of Europe, in relation to time of winter, location and temperature. We used data from 221 dissected birds, shot in Britain in two winters (2013/14, 2014/15), and 1689 live birds captured during six consecutive winters (2010/11-2015/16).

3.Woodcock are able to store large amounts of energy as fat in mid-winter and increase energy reserves as night air temperature drops to below 0°C, provided the ground thaws during the day.

4.In the event of cold weather in Britain, the mean potential flight distance of woodcock, based on mobilisable energy estimates of shot birds, is 860 km. If they do not move away, woodcock could withstand frozen conditions without feeding for a mean of six days.

5.Synthesis and applications. To reduce the effects of cold weather on Eurasian woodcock Scolopax rusticola, shooting should be restricted before energy reserves are depleted. Current policies vary across Europe, but our results suggest that restrictions should come into force sooner, after four days of continually frozen ground at inland sites. Restrictions should cover large regions and remain in operation for seven days after the end of the cold spell.

1. 严酷的冬季天气会降低鸟类的能量储备。在此类情境下，通过基于科学的政策减少干扰、进而降低能量消耗，对于缓解其对生存的负面影响至关重要。
2. 本研究通过异速生长方程（allometric equations），分析了欧亚丘鹬（Eurasian woodcock Scolopax rusticola）的能量储备情况——该物种是欧洲大部分地区广受欢迎的狩猎猎物物种——并探讨了其与冬季时段、采样地点及气温的关联。本研究使用了两类样本数据：一是2013/14、2014/15两个冬季在英国射杀的221只经解剖的个体，二是2010/11至2015/16连续六个冬季捕获的1689只活体个体。
3. 若日间土壤解冻，欧亚丘鹬可在隆冬时节以脂肪形式储存大量能量，并在夜间气温降至0℃以下时提升自身能量储备。
4. 基于对射杀个体的可动用能量估算，英国遭遇寒冷天气时，欧亚丘鹬的平均潜在飞行距离可达860千米。若不进行迁徙，该物种可在不进食的情况下耐受冰冻环境，平均时长为6天。
5. 综合分析与应用建议：为降低寒冷天气对欧亚丘鹬的负面影响，应在其能量储备耗尽前限制狩猎行为。当前欧洲各地的相关政策存在差异，但本研究结果显示，在内陆地区连续冰冻四天后，就应尽快实施狩猎限制。此类限制需覆盖大范围区域，并在寒潮结束后持续生效7天。