The diminutive varroa mite has been found at a third Hilo location, raising concerns about the Big Island's feral and captive bee populations.

The varroa mite is considered one of the most serious honey bee pests and is found across much of the world. These bee parasites pose a potential problem for farmers and beekeepers who depend upon the bees to pollinate crops, make honey and raise queen bees for export.

Twenty-four varroa mites were found Friday near Banyan Drive near Hilo Bay by the state Department of Agriculture, the state reported yesterday. The mites were found within a half-mile of two earlier detections on Aug. 22 and 23, bringing the total number of bee mites found in the Hilo area to 38 mites from a total of about 30,000 trapped bees.

So far, varroa mites have not been detected in any managed hives in Hilo. That could be good news for the Big Island's four producers of queen bees, which according to the state generate annual sales of more than $4 million.

Hawai'i queen bees command a premium price because they're mite-free.

Bee-killing varroa mites, which were first detected in O'ahu hives last April, could cost farmers $42 million to $62 million a year if they wipe out the state's bee population, according to a preliminary estimate by the state Department of Agriculture.

The mites weaken adult bees and cause baby bees to be deformed. They spread from hive to hive through bee contact.

On O'ahu, crop losses are estimated to range from $10 million to $15 million a year, under the department's worst-case scenario.

The state yesterday urged Hilo residents to report feral beehives and bee swarms to the state's toll-free Pest Hotline at 643-PEST (7378). The state also is asking beekeepers and the public not to transport bees or beekeeping equipment in or out of a 15-mile radius of Hilo Bay.

State officials already have a quarantine order in place preventing the interisland movement of bees and beekeeping equipment.