Narrator: This is Science Today. Pollinators, such as bees, birds and bats, help one-third of the world's crop production. So news of the decline of the honey bee population has been especially troubling, but there are a lot of things that farmers can do. Claire Kremen, a conservation biologist at the University of California, Berkeley says her group is doing outreach with California farmers.

Kremen: So, some of the things that farmers could do from easiest things to more difficult - they could just be more tolerant of having some weeds around that also bloom; they could use cover crops and then allow those cover crops to flower; they could switch from monoculture to a polyculture, having multiple things grow at a time that flower at different times that flower at different times.

Narrator: Bees also need different kinds of pollen at different times of the year, so Kremen says having a suite of resources available is very important.

Kremen: A lot of bee species, including honey bees, need diverse floral resources. They need it for their own nutritional well-being because just like you, if you only ate rice all day long, everyday, then you wouldn't be very healthy. Bees also need to eat different kinds of pollen.

Narrator: For Science Today, I'm Larissa Branin.