Retrospective Analysis of American Woodcock Population and Harvest Trends in Canada

American Woodcock Symposium(2019)

引用 0|浏览0
暂无评分
摘要
We used data from the Canadian component of the annual American Woodcock Singing-ground Survey (SGS) and data from the Canadian National Harvest Survey between 1975 and 2015 to assess temporal fluctuations in the population index, the number of American woodcock (Scolopax minor; hereafter, woodcock) harvested in Canada, and the proportion of successful hunters in Canada. We performed analyses via generalized additive mixed models that allowed us to identify periods when there were significant changes in temporal trends, and years during which there were significant changes in the direction of the temporal trajectory. We included climatic conditions before, during, and after the nesting and brood-rearing seasons (i.e., prior to the hunting season) as explanatory variables in our model. We did not find any effect of climatic variables on the SGS index. The SGS population index showed a slow overall negative decline in Canada, but there were only 2 significant periods of decline (1978–1984 and 1992–1994). Woodcock harvest and the proportion of successful woodcock hunters increased with the size of the SGS population index in the spring. The total harvest and the proportion of successful hunters remained fairly stable during the study period, but both indices showed a period of significant decline that started ca. 2006, and that was followed by a period of significant increase that started ca. 2009.
更多
查看译文
AI 理解论文
溯源树
样例
生成溯源树,研究论文发展脉络
Chat Paper
正在生成论文摘要