艾伯塔省的冬季鸟类数量创下历史新低,常绿球果的短缺与下降有关。
Winter bird counts in Alberta hit record lows, with shortages of evergreen cones linked to the decline.
今年冬天,艾伯塔省卡纳纳斯基斯县的鸟类数量创下历史新低,仅统计了 449 只鸟和 29 个物种,远低于 1,216 只鸟和 34 个物种的平均水平。
Bird counts in Kananaskis Country, Alberta, hit record lows this winter, with only 449 birds and 29 species counted, far below the average of 1,216 birds and 34 species.
这种下降与常绿乔木上新球果的短缺有关,常绿乔木是重要的食物来源。
The decline is linked to a shortage of new cones on evergreen trees, a critical food source.
晚喙鸟已经消失了五年。
The evening grosbeak has been absent for five years.
圣诞鸟类计数 (Christmas Bird Count) 提供有关鸟类种群的重要数据,是世界上运行时间最长的野生动物普查。
The Christmas Bird Count, which provides vital data on bird populations, is the world's longest-running wildlife census.