Scientists battling mites
Sep 27, 2004 9:30 AM
Russian bees suffer only a third to half of the mites that plague Italian hives, Tim Rinderer, director of the U.S. Department of Agriculture's Bee Lab, said, and the new lines have enabled some beekeepers in New York to forego using chemicals to control mites. â€œI have some confidence in the next few years we will be producing bees that donâ€™t need chemicals at all,â€ he said.
By Bruce Schultz
A tiny pest brought the U.S. honey bee industry to its knees, but a Louisiana scientist found a remedy in remote Russia. Two different types of mites were detected in American honey bees in the mid-1980s. â€œTracheal mites showed up in 1984. Then shortly after that we had varroa mites,â€ said professional beekeeper Charlie Harper of Carencro. â€œBefore then, beekeeping was a lot easier.â€ For a few years, pesticides could control varroa populations â€” the biggest threat to honey bees â€” but eventually the mites became immune to chemicals, Harper said, using graphic but effective terms to describe how varroa mites harm bees. â€œA varroa mite on you would be like a tick the size of a rat sucking your blood.â€ In addition, he said, varroa mites transmit diseases to bees. Varroa mites are capable of 10 to 15 generations in a year, according to Tom Rinderer, director of the U.S. Department of Agricultureâ€™s Bee Lab in Baton Rouge, La., and an adjunct LSU AgCenter entomology professor. â€œPeople were losing 80 percent of their colonies during the winter,â€ Rinderer said. LSU AgCenter entomologist Dale Pollet said honey bees have a significant role in agriculture, providing $400 million in pollination in Louisiana, $4 million in honey production and $300,000 in sales of apiary supplies. â€œAbout 60 percent of the food we eat is directly or indirectly due to bees,â€ Pollet said of the beesâ€™ roles in pollination and honey production. The demand for a solution prompted Rinderer to find an area where honey bees had adapted to mites. He knew of a Siberian area of Primorsky in Russia where Ukranian emigrants brought bees with them when they migrated there in the mid-1800s. Originally the bees werenâ€™t exposed to varroa mites until being moved to their Siberian home, Rinderer said. The bees that could survive the harsh winters and endure varroa mites were the only ones to prosper, he said, and beekeepers probably used no breeding techniques. â€œI think there was an opportunity for natural selection to take place,â€ he said. After the USSR was formed, the Primorsky naval port of Vladivostok was closed to outsiders because of its military activities there, Rinderer said, but military officers assigned to the seaport enjoyed beekeeping as a hobby. After the USSR collapsed, Rinderer ventured to Primorsky to explore the possibility of bringing Russian honey bees to the United States as a possible solution to the varroa problem. The Primorsky beekeepers didnâ€™t seem to be worried about the mite problem, Rinderer said. â€œThey were much more casual about it,â€ he said. But getting the honey bees from Russia to Rindererâ€™s lab in Baton Rouge wasnâ€™t a casual endeavor. â€œIt took two years just to get bees in Vladivostok to a bee yard here,â€ he said. After that, experimental colonies were established at an isolated location in Louisiana near Grand Isle. Breeding was aimed at taking only the best colonies before releasing a line of queens. The breeding program is even more intensive now, Rinderer said, with selections made to obtain the best queens. Russian queens are being produced in Iowa to subject them to harsh winters, and in Mississippi and Louisiana, with the best chosen for breeding lines. â€œThat will be a continuous effort,â€ Rinderer said. â€œItâ€™s got huge potential left. Itâ€™s not a finished project.â€ Beekeepers are making the transition from Italian bees to Russians, but the change takes some adjustment. â€œTheyâ€™re a different bee,â€ Rinderer said. â€œThey look pathetic in the springtime.â€ After winter, the colony is small â€” with no brood being produced until late spring, he explained. â€œThey look like theyâ€™re on the verge of death.â€ The Russians arenâ€™t fooled by the sudden warm-ups of Louisianaâ€™s early spring, he said, but once the pollen flow begins, the Russian bees shift into high gear. â€œThey sit back until itâ€™s obvious spring is here,â€ Rinderer said. In fact, beekeepers have to prepare extra hive space for expansion, he said. Russian bees suffer only a third to half of the mites that plague Italian hives, Rinderer said, and the new lines have enabled some beekeepers in New York to forego using chemicals to control mites. â€œI have some confidence in the next few years we will be producing bees that donâ€™t need chemicals at all,â€ he said. Harper said his beekeeping operation depends less on chemical defenses. â€œIâ€™m going without chemical treatment on the Russian hives I have,â€ said Harper, vice president of the Louisiana Beekeepers Association. Harper sells Russian breeder queens to other queen bee breeders. This year he shipped queens to New York, California, Florida, Mississippi, Texas, Arkansas, both Carolinas and Georgia. After Canada opened its border for U.S. queen shipments, he sent an order there for six queens. To make a queen, a larva is placed in a plastic cell, positioned vertically in the hive, unlike the other cells in a hive that are horizontal, and worker bees feed the larva royal jelly. The queen mates with drones, then starts laying up to 2,000 eggs per day. â€œThatâ€™s all a queen is â€” an egg-laying machine,â€ Harper said. His customers will use the $500 breeder queens to produce new queens that will be sold for $10 to $15 each to beekeepers. The Russians are immune to tracheal mites that block beesâ€™ airways, and they have resistance to parasitic varroa mites. Russian hives also arenâ€™t as conducive for mites to reproduce. Pollination from honey bees is essential for many agricultural crops that arenâ€™t self-pollinating. Harper said the almond industry in California relies heavily on honey bees, and almond farmers had to cope with a bee shortage this year. Crops such as pears, cherries, apples, melons and cucumbers also require pollination. In southern Louisiana, honey bees get most of their honey from tallow trees, also known in some areas as chicken trees, he said. â€œA lot of people donâ€™t realize tallow trees are good for something,â€ Harper said. All honey bees in the New World were imported, Rinderer said, with Italian bees becoming the preferred breed. The Bee Act of 1911 prohibited importation of honey bees into the United States, but someone apparently violated that law, inadvertently introducing the varroa mites into American hives, Rinderer said. A study conducted by the USDA Bee Lab indicates Louisiana may be spared from the spread of Africanized bees, commonly known by the exaggerated name of â€œkiller bees.â€ The study indicates that in more than a decade the bees have not been able to migrate to areas with more than 55 inches of annual rainfall. â€œAfricanized bees seemed to have reached their limit of spreading,â€ Rinderer said. â€œThey seem to be stuck in east Texas, and the ones that are stuck there are hybridized and not anything like pure African.â€