The overall state of birds can seem rather grim. Almost a third of North American bird species are in decline, and in the last five decades, more than 100 species have lost over half of their populations. This is primarily due to lack of food—fewer insects to eat—and habitat loss, like the development of grasslands. 

But there’s a bright spot: Some birds that were once rare are now abundant, like the merlin, sandhill crane, and pileated woodpecker. 

Host Ira Flatow talks with biologist Tom Langen, who explains these birds’ remarkable comebacks, and discusses his conservation work to bring threatened fish species back from the brink. 

Guest: Dr. Tom Langen is a professor of biology at Clarkson University.

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