OVERTON -- Due to the varroa mite, a parasite that kills or deforms honeybee larvae, approximately 90 percent of the wild bee colonies in East Texas have been eliminated, according to Dr. Rodney Holloway, extension entomologist.
Those wild bee colonies that survive may possess some degree of genetic resistance to the varroa mite, which has decimated domesticated bees both in the United States and Europe, said Holloway, speaking to 140 people attending a recent pesticide applicator recertification conference at the Texas A&M University Agricultural Research and Extension Center at Overton in Rusk County.
Finding genetic strains of wild or "feral" honeybees that are resistant to the varroa mite is essential to the raising and care of bees for commercial or agricultural purposes. While the mite has nearly wiped out feral colonies, it is also decimating domesticated hives. Honeybees not only produce honey for human consumption but pollinate many important East Texas crops, including cantaloupes, cucumbers, pumpkins, pears, apples and watermelons.
Watermelons are particularly dependent upon pollination. Each watermelon blossom requires about 1,000 grains of pollen, or about eight bee visits, to be pollinated. Just as critical, the blossom is only open during one day of the growing season. Without pollination, the melon will grow to about 1-1/2inches long and abort. If it's not fully pollinated, the watermelon may be undersized or misshapen.
Fortunately for East Texas, Apistan strips, the only chemical control for varroa mites, still rids hives of the pest. But in the Southeast United States, misuse of a related chemical has resulted in the development of a mite population resistant to the strips, Holloway said.
For reasons unknown, the mites have not become a widespread problem in Central Texas, but remain confined to East Texas hives.
If Texas varroa mites were to become resistant to Apistan, then it would be "a very serious situation" because there's no other product available to control the parasite. If this were to happen, then finding genetically resistant lines in the feral bee population might become essential to a domestic honeybee breeding program, he said.