A UC Davis study found that the population of tricolored blackbirds in California is falling dangerously low, reported Kurtis Alexander in the San Francisco Chronicle.

The birds, which numbered in the millions 100 years ago, are now down to about 145,000 in all. One reason for the decline, the article said, is the agricultural harvest. Before agriculture dominated the landscape, the birds nested in the valley floor's native tules, shrubs and grasses. The birds adapted to nesting in the vast fields of wheat, oats and other crops grown to feed dairy cattle. However, when the crop is harvested, many birds are caught up in...