bird population

基本解釋

Three of the cases they studied found that the rise of West Nile virus in the U.S. corresponded to decreases in bird population density.
他們在研究過的三個案例中發(fā)現(xiàn)西尼羅河熱在美國的的流行與鳥類種群密度的下降相關。
Alaska's Rat Island is finally rat-free, 229 years after a Japanese shipwreck spilled rampaging rodents onto the remote Aleutian island, decimating the local bird population.
阿拉斯加的鼠島，在狂怒的嚙齒動物從一艘日本遇難船涌入這個遙遠的阿留申島嶼、大量殺害當?shù)伉B類的 229 年之后，終于沒有老鼠了。
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Bird songs and calls as one of the most important features, which contain abundant biological information, are vital for the research of Avi-behavior, bird population structure and classification.
鳥類的鳴聲中包含有豐富的生物學信息，研究鳴聲對于了解鳴聲與行為的關系、鳥類的種群結構及種屬分類具有重要的實際意義。

Before the experiment got under way, they surveyed the bird population in every patch of woodland each season for two years—in other words, eight times in all.
ECONOMIST: Ecology: Under the mistletoe The
No-till, practised more in America than in Britain, means growing crops without ploughing fields, and leads to many-fold increases in bird population and a range of other environmental benefits.
ECONOMIST: What the birds and bees say