A national survey of managed honey bee 2015–2016 annual colony losses in the USA

Abstract

Managed honey bee colony losses are of concern in the USA and globally. This survey, which documents the rate of colony loss in the USA during the 2015–2016 season, is the tenth report of winter losses, and the fifth of summer and annual losses. Our results summarize the responses of 5725 valid survey respondents, who collectively managed 427,652 colonies on 1 October 2015, an estimated 16.1% of all managed colonies in the USA. Responding beekeepers reported a total annual colony loss of 40.5% [95% CI 39.8–41.1%] between 1 April 2015 and 1 April 2016. Total winter colony loss was 26.9% [95% CI 26.4–27.4%] while total summer colony loss was 23.6% [95% CI 23.0–24.1%], making this the third consecutive year when summer losses have approximated to winter losses. Across all operation types, 32.3% of responding beekeepers reported no winter losses. Whilst the loss rate in the winter of 2015–2016 was amongst the lowest winter losses recorded over the ten years this survey has been conducted, 59.0% (n = 3378) of responding beekeepers had higher losses than they deemed acceptable.