He links oil pollution to heart defects in Gulf killifish . Lingering oil residue at the bottom of Gulf Coast marshes caused heart defects and hindered reproduction in a small fish seen as an environmental bellwether , researchers said Thursday . The bird is the ` ` canary in the coal mines '' for the Gulf region , scientist says .
He links oil pollution to heart defects in Gulf killifish . The bird is the ` ` canary in the coal mines '' for the Gulf region , scientist says .