But the link between the drop in chimney swift numbers and chimney loss is not clear.

但是，烟囱雨燕数量的下降和烟囱减少之间的联系尚不清楚。

Chimney swifts are fundamentally a South American bird that visits North America for four months, she said.

" 从根本上说，烟囱雨燕是一种南美鸟类，只会在北美停留四个月。"

But the app also identified birds like chimney swift, northern flicker, fish crow, killdeer and gray catbird.

但这款应用程序还识别出烟囱刺尾雨燕、北美榆斑啄木鸟、鱼鸦、双领鸻和灰猫嘲鸫等鸟类。

In 2005, Hurricane Wilma deposited a flock of North American chimney swifts in Western Europe.

2005 年， 飓风威尔玛在西欧沉积了一群北美烟囱雨燕。

Rubega said a big problem is that scientists have only a few reports of small numbers of chimney swifts in the upper Amazon Basin.

鲁贝加指出，其中一个主要问题是，科学家们只有几份关于亚马逊河盆地上游少量烟囱雨燕的报告。

But the link between the drop in chimney swift numbers and chimney loss is not clear. The flying insects that swifts eat also appear to be declining.

但是，烟囱雨燕数量下降和烟囱减少之间的联系尚不清楚。雨燕捕食的飞虫似乎也在减少。