I wonder what they use as acaricide apart from amitraz?Collaborating commercial beekeeping operation information Twenty monitor hives were established in April 2009 by a large-scale (>72,000 hives), migratory commercial beekeeping operation (Mississippi, California, and South Dakota, U.S.A.) that experienced CCD-losses in 2007/08. Standard beekeeping management practices for an operation of this size were employed. Treatment regimes throughout the year were as follows: (1) anti-mite treatment April 2009, just prior re-queening – amitraz; (2) antibacterial treatment May 2009 - oxytetracycline hydrochloride (OTC) (Terramycin™); (3) anti-fungal (*Nosema sp.*) treatment August 25, September 12, and October 13, 2009 - fumagillan; (4) antibacterial treatment late August, early September, 2009 - tylosin tartrate; (5) anti-mite treatment September 12, 2009, after harvesting honey; (6) anti-mite treatment – early November and early December 2009 - essential oils from lemon grass and spearmint (Honey-B-Healthy™). Honey bees colonies were periodically supplemented with sugar syrup and protein supplement. In April (1 gallon) and October (2 gallons) bees were fed 50% (weight/volume) sucrose; in November all colonies received 3 gallons of a 1:1 mixture of high fructose corn syrup-55 (HFCS-55, 55% fructose, 42% glucose) and sucrose syrup. Additional sugar syrup was given to colonies based on colony weight (<80 lbs - 3 gallons, 80–90 lbs - 2 gallons., 90–100 lbs – none). This operation experienced an average 18% colony loss from November 2009 to February 2010. Colonies with younger queens (≤2 years old) experienced 11% loss, whereas colonies with older queens experience 21% loss. -- Juanse Barros J. APIZUR S.A. Carrera 695 Gorbea - CHILE +56-45-271693 08-3613310 http://apiaraucania.blogspot.com/ [log in to unmask] *********************************************** The BEE-L mailing list is powered by L-Soft's renowned LISTSERV(R) list management software. For more information, go to: http://www.lsoft.com/LISTSERV-powered.html Guidelines for posting to BEE-L can be found at: http://honeybeeworld.com/bee-l/guidelines.htm