John V. Westra
|[Image: Tony Stelzer of the USDA/ARS]|
|[Image: Close up of an adult Varroa mite.]|
|[Image: Adult parasitic Varroa mite on the back of a honey bee]|
|[Image: Beekeeper holding a Russian queen bee]|
|[Image: USDA-ARS research scientists isolating a Russian queen]|
|[Image: USDA-ARS research scientists examining colonies of Russian bees.]|
Most people don’t give honey bees much thought, but the honey they produce is an economically important agricultural crop, generating $2.5-$5 million annual sales in Louisiana and $150-$250 million annual sales in the United States. Additionally, pollination by honey bees is an essential part of the production of many vegetable, fruit and nut crops in the United States. Unfortunately, the recent infestation of honey bee colonies by a parasitic mite called Varroa destructor has contributed to a significant decline in beekeeping. Varroa mite infestations weaken or destroy bee colonies. As a result, producers and their bees spend much of their effort rebuilding or replacing colonies instead of growing them and producing honey. As this persists, beekeepers who sustain economic losses leave the industry. U.S. Department of Agriculture (USDA) data from 1987 through 2002 indicate 55 percent of the farms with bee colonies quit keeping bees during that period. This decline in beekeepers has led to a 17 percent reduction in the number of bee colonies and a 29 percent reduction in honey production.
Until recently, options for controlling Varroa mites were limited to a few miticides. The continued effectiveness of these products is uncertain because Varroa mites appear to be developing resistance to them. Because infestation of Varroa mites can cause substantial damage, producers have been seeking any economical means for controlling them. To assist beekeepers, the USDA Agricultural Research Service Honey Bee Breeding, Genetics and Physiology Research Unit in Baton Rouge developed and released commercial queens from a line of Russian honey bees resistant to Varroa mites.
A few years after these Russian queens with Varroa resistance were released commercially in 2000, the USDA/ARS contacted the Department of Agricultural Economics & Agribusiness to determine how many beekeepers were using these queens and to calculate the economic impact of this line of bees. To help answer these questions, we mailed surveys to approximately 1,000 beekeepers nationwide who belonged to the major U.S. beekeeping associations – the American Beekeeping Federation and the American Honey Producers Association. Usable information was obtained from 55 percent of beekeepers surveyed.
Two-thirds of beekeepers indicated Varroa mites were a “very serious” or “extremely serious” problem in their operation. Beekeepers reported that losses from Varroa mites nearly doubled from 174,000 colonies in 2001 to 342,000 colonies by 2004. To control Varroa mites, beekeepers have used a variety of methods, with miticides being the most common practice. Unfortunately, one-third of beekeepers indicated Varroa mites in their areas have developed resistance to one or more miticides. As a result, 25 percent of beekeepers surveyed had used lines of bees – including Russian queens – developed to control Varroa mites.
To determine the number of colonies with Russian queens, we expanded the survey data using a factor derived from the most recent data available on the number of colonies in the United States. Using this factor, we estimated that 113,000 colonies with Russian queens were kept in the United States in 2004 (3 percent of colonies nationwide). By 2007, this is estimated to have increased to 5 percent of the U.S. production (117,000 to 143,000 colonies).
Estimated Economic Impact
To determine the potential direct economic impact of Russian queens being used by U.S. beekeepers, we considered marginal changes in revenues and production costs associated with Russian queens. Potential changes in revenues include pollination fees and honey sales. Because pollination fees for colonies of Russian and non-Russian queens were essentially the same in 2004, they were excluded from this analysis.
Beekeepers indicated that honey production was 64 pounds per colony with Russian queens in 2004 while non- Russian colonies averaged 78 pounds per colony. This difference of 14 pounds of honey per year, when multiplied by the $1.23 per pound responding beekeepers indicated they received for bulk honey, yielded $17 per colony revenue shortfall for Russian queens.
Because most production practices were similar for Russian and non-Russian lines of bees, we examined changes in the amount of miticides used to control Varroa mites (2 percent of estimated total production costs). Though beekeepers used less miticide on Russian colonies than non-Russian colonies, the difference was not statistically significant. One possible explanation is that 75 percent of beekeepers who purchased Russian queens apparently did not purchase pure Russian queens (Russian queens mated to Russian drones). These queens likely had lower genetic resistance to Varroa mites; therefore, beekeepers might have resorted to miticide treatments for these hives similar to those for non-Russian hives. Other possible reasons could be risk aversion to potential loss of colony from mites, even with resistant queens, or habit – treating miticides, though at slightly reduced rates, even when bees in the colonies are from resistant queens. Assuming beekeepers were risk-neutral and had pure Russian queens, the need for miticide treatments would be greatly diminished or eliminated. The cost savings in miticides in this situation would be $18 to $20 per colony per year – more than offsetting any reduction in revenues from lower honey production. In this situation, the direct economic impact from Russian queens, with estimated honey revenue reductions of -$17 and cost savings from reduced miticide treatments of $19, would be about $2 per colony per year. The estimated annual total direct economic effect ranged from $227,000 to $286,000 nationwide.
As beekeepers become more familiar with managing Russian queens, it is likely that the difference in honey production between colonies with Russian queens and those of non-Russian queens, will be eliminated. Research shows average honey production of hives with Russian queens was equal to or greater than those of non-Russian hives. In that situation, gross revenue would show no difference. As in Scenario 1, with negligible miticide use, the direct economic impact of Russian queens would be $18 to $20 in cost savings per colony per year. With net positive benefits of $19 per colony the direct economic impact nationwide, would range from $2.2 to $2.7 million annually.
We looked at how these two scenarios would affect the direct economic impact of Russian queens in the U.S. beekeeping industry. Under the first scenario, with lower honey production but lower production costs for the Russian queens, net revenues increased by $2 per colony and resulted in approximately $250,000 of direct economic benefits annually. Under the second scenario, with honey production equal for hives with Russian and non-Russian queens and lower production costs for Russian hives, direct economic impacts were approximately $2.5 million annually. In the long run, results from the second scenario are more likely as beekeepers adapt management practices for the Russian queens and honey yields increase. Because many of the early adopters of this technology are located in the South, the release of Russian queens may have larger economic benefits to beekeepers in this region of the country. In the Delta states of Louisiana, Mississippi and Arkansas alone, the economic benefits may exceed $1 million annually.
These findings highlight the positive and large economic impact that Russian queens potentially have on the beekeeping industry, particularly in the Delta. This potential has not been realized yet, primarily due to the recent commercial release of Russian queens. Unfortunately, this potential may be severely diminished if the vendors of Russian queens do not maintain the integrity of the genetic material and the associated benefits of Varroa mite resistance. The industry must maintain genetic integrity of Russian queens and the associated benefits in controlling Varroa mites. Efforts by extension educators at field days, demonstrations and producer-to-producer information exchanges will help inform beekeepers of the benefits of Russian queens in addressing mite problems and of the importance of maintaining the genetic and behavioral benefits of this line of bees.
John V. Westra, Assistant Professor, Department of Agricultural Economics & Agribusiness, LSU AgCenter, Baton Rouge La.
Jeffrey Harris, research entomologist, and Thomas Rinderer, research leader, the USDA-ARS Honey Bee Breeding, Genetics and Physiology Research Unit in Baton Rouge, La.
(This article was published in the summer 2007 issue of Louisiana Agriculture.)