Scientists in the US have developed maps that reveal the populations of wild bees in the US. The maps show “hotspots” where crops could fail in the future, as a disturbing trend illustrates that bee populations are dropping in the regions of the country that need them most.
Dozens of staple foods depend on bees for pollination, including almonds, apples, berries, onions, and broccoli. Because of declining bee populations in the past decade, farmers have come to depend more on domestic honey bees to keep their crops thriving. But as University of Vermont environmental planner Inso Koh and his colleagues point out in a new paper in the Proceedings of the National Academy of Science, wild bees are also crucial, accounting for at least 20 percent of bee pollination.
These wild bees also require large areas of grassland for their habitats. And those habitats are vanishing, as more farmers turn grassland into agricultural ecosystems devoted to corn, soy, and other crops that aren't dependent on bees as pollinators.
Koh and his colleagues modeled what wild bee populations look like now—and how this might change in coming years. Then the researchers asked fourteen experts in bee ecology to assess which areas could serve as decent habitats for the roughly 4,000 species of wild bees that live in the US today.
After their analysis, the research team found that wild bee populations have declined in 23 percent of the US over the past several years. And this has implications for future food security. Koh and his colleagues show that 39 percent of croplands that depend on bee pollination are in areas where wild bee numbers are shrinking.
Koh told Ars via e-mail that domestic honey bees can make up for some of these losses, but "we need to do a better job of integrating wild bees in crop pollination systems." Especially given that honey bees are also suffering dramatic losses, we can't afford to lose wild bees that Koh says are "very efficient and give us their pollination for free—all we need to do is provide them with a suitable habitat."
He and his colleagues hope that these maps of wild bee decline can help government agencies and land planners determine the best locations for bee habitat conservation. The fates of our delicious fruits and vegetables may depend on it.
Source: arsetechnica.com
