Twenty -two WVBA PNWhoneybeesurvey respondents supplied information about some managements they utilize for the PNW loss survey www.pnwhoneybeesurvey.com Respondents could select multiple options and there was always a none and other selection possible. One of the 22 survey respondents had over 20 colonies and had a heavy loss (68%) and as an outlier was removed from the analysis. This reduced average loss to 22% for analysis.
The remaining 21 checked 59 feeding options = 3/individual (statewide it was 2.9/individual). One individual with a single colony indicated no feeding and lost it = 100% loss; this individual was one of 14 statewide and their collective loss was 40%, 5 percentage points greater than average loss statewide.
Four WVBA individuals selected a single choice (sugar syrup) and had 29% loss (same as average). Four individuals indicating 2 feeding options had 35% loss (2 selected pollen patty and sugar syrup (33% loss), 1 pollen patty and honey (22% loss) and the 4th selected sugar syrup and hard candy (100% loss). Six individuals indicated 3 choices (19%, loss), five of which combined pollen patty, sugar syrup with dry or hard sugar. Six had 4 and 1 had 5 choices and they had a 19% loss. The individual with the heavy colony loss (lost 17 colonies – 68%) made 6 choices. Clearly doing more feeding helped decrease loss and improve survival.
WVBA respondents provided 56 responses (3.1/individual (statewide-2.9/individual) regarding wintering management practices. Three individuals indicted they did none. They had a 23% loss compared to 22% average of the 21 respondents; 42 statewide individuals doing none had a 39% winter loss, 4 percentage points higher loss than overall loss of 35%.
For those indicating some managements, three did one single thing, (33% loss – only the individuals using the ventilated board (had loss of 9%), other than total loss. Five individuals indicated 2 selections (32% loss – upper entrance and ventilated board had 19% loss, the best of the selections), 3 did three (60% loss, the one individual not included also indicated 3 selections), and 7 individuals had 4 or 5 selections for only a 11% loss. No one combination was dominant. More managements practiced generally resulted in better survival as there is no one practice of winterizing that greatly improves survival.
Sanitation should be our norm in colony management. However, of the alternatives only distinctive hive colors (6 individuals, 13% loss) and cleaning hive tool (9 individuals, 19% loss) offered an advantage better than average loss.
Screen bottom board SBB – Eighteen individuals used SBB screen bottom boards (had 21% loss) and the 3 that did not had double that loss – 42%. Two of the 18 said they never blocked the SBB during winter (they had 100% loss, 3 colonies). Statewide over past 7 years the differences were much more modest. There was 4 percentage point gain in survivorship with SBB use and then for those who closed a 3-point difference over those who did not.
Non-chemical controls – The survey asked about non-chemical mite treatments There were 46 choices, 2.4/individual. Fourteen percent of statewide respondents, 2 WVBA members, said they did not employ a non-chemical mite control; those who did not use a non-chemical treatment reported a 48% winter loss; the 2 WVBA members (4 colonies) had no loss. Some non-chemical control alternatives demonstrate an advantage in one or two years, but overall, result in little survival improvement.
Three of the non-chemical alternatives statewide have demonstrated reduced losses over past 5 years. Reducing drifting such as spreading colonies (33% loss average for 3 years and brood cycle break (36% average) have consistently year after year demonstrated better survival than average loss (41%). This year for WVBA members both had 19% loss levels , 3 percentage points better than average. Different colony colors in apiary and drone brood removal were both 41%, 5-year average.
Chemical controls – The 45 individuals Statewide survey respondents who did not use a chemical control lost 61% of their colonies; 57% loss for the 3 WVBA members not using any controls. Those using chemicals used at rate of 1.9/individual. Seven individuals used one chemical (had 48% loss level; the 2 using MAQs had 26% loss, the 2 using Apivar had 33% loss), seven individuals also used two (17.5% loss), three used 3 or 4 and had 11% loss. Loss levels declined with combining uses.
It is clear that WVBA members can obtain even better survival than the 22% average with four chemicals – Apivar, Apiguard, MAQs and Oxalic acid vaporization. All four chemicals improved survival for WVBA members this year, when losses were lower and have for the past four years in the statewide results. Formic Pro has looked particularly good statewide the last 3 years (25.3% loss 3-year use average) but the single user in WVBA had 100% loss (3 colonies).
See results and further discussion on the PNW honeybeesurvey website under both state and club results www.pnwhoneybeesurvey.com