Transcript for New study reveals birds have been shrinking over last 40 years
Next story is for the birds recently told you about a huge decline in the bird population in North America. Now there's a new concern a new study being called the largest of its kind wardens that birds are shrinking. Scientists say nearly all of the species they've studied. Have been getting smaller in the last forty years and they blame climate change one theory is that smaller birds are better at. But scientists also found the bird's wings fans are growing to help them migraines. Thing.
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