California's deepening drought is shrinking its rice harvest, and that's bad news for farmers, migratory birds and sushi lovers.

The $5 billion industry exports rice to more than 100 countries and specializes in premium grains used in risotto, paella and sushi. Nearly all U.S. sushi restaurants use medium-grain rice grown in the Sacramento Valley.

The rice harvest is just the latest victim of California's historic drought, which has sharply reduced crop production as it enters its fourth year. With 95 percent of the state in "severe" to "exceptional" drought, farmers are leaving fields unplanted, cattle ranchers are reducing herds and almond growers are tearing out orchards.

California, the nation's second largest rice-growing state after Arkansas, usually produces more than five million pounds of rice and sells about half of it abroad.

But this year rice farmers only planted 420,000 acres — 25 percent less than last year — because of water restrictions, according to the California Rice Commission.

On a clear October day, farmer Mike DeWit watched as a giant combine harveste

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