Honey bee loss ratios down in quarterly data
MADISON – A report tracking honey bee colony quarterly totals issued early this month by the Wisconsin field office of the National Agricultural Statistics Service indicated that the losses in the state during the April to June quarter were the smallest during the latest six quarter period.
In the statistics compiled for operations with at least five honey bee colonies, the loss of 2,900 colonies (or 4 percent) for the April-June 2017 period was down from the loss of 5,500 colonies (rate of 7 percent) for that quarter in 2016, the report noted.
For the 2017 spring quarter, Wisconsin honey bee operations had an estimated 65,000 colonies compared to 78,000 for that period in 2016. Of the 65,000 colonies, 47,000 were brought into the state after April 1 of this year, the report indicated.
Varroa mites were cited as the main reason for colony losses during each of the last six quarters in the state. The producers reported that 13.7 percent of their colonies were affected by the mite during the April-June 2017 quarter, down from the 69.3 percent for the 59,000 colonies during the October-December quarter at the end of 2016.
In addition to the varroa mites, colony health was affected in several other ways for the April-June 2017 quarter – 2.1 percent for pesticide exposure, 1.7 percent by disease, 1.6 percent by other pests and parasites, and 2.5 percent for other reasons such as weather, starvation, queen failure, or a lack of flowering plants on which to forage, the report pointed out.
For the United States, which had 2.89 million honey bee colonies at the start of April in the operations with at least five colonies, varroa mites were also cited as the main cause of colony stress. The report indicated that 41.6 percent of the colonies were affected during the April-June quarter this year compared to 53.4 percent a year earlier.
Honey bee losses attributed to the colony collapse disorder syndrome totaled 84,400 colonies for the January-March quarter of 2017. This was, however, a 27-percent decrease from those losses – for which four criteria must be met – from the first quarter of 2016.