Wildlife officials in Arkansas say that they still have no idea why more than 100,000 fish washed up dead along a stretch of river last year, but they have a theory on why thousands of blackbirds fell from the sky. The Arkansas Game and Fish Commission—echoing earlier findings—says it believes the birds collided with each other after being startled by loud noises, likely New Year's Eve fireworks. Radar images from the time and area of the bird deaths show blackbirds suddenly taking off from a roost estimated to contain 1.6 million birds.
The fish kill, however, remains mysterious. Tests on the fish and on the water they were found in have not turned up anything that would explain such a large number of dead fish. "We probably will never know exactly what killed these fish," a commission official tells AP. "But the testing has eliminated the largest public concerns of disease, parasites and toxins. We have no reason to think fish caught in the Arkansas River are unsafe to eat." (Read more animal deaths in Arkansas stories.)