UNITED STATES DEPARTMENT OF AGRICULTURE 



1 BULLETIN No. 804 



Contribution from tlie Bureau of Entomology 

 L. O. HOWARD, Chief 



Washington, D. C. 



PROFESSIONAL PAPER 



March 16, 1920 



A STUDY OF THE BEHAVIOR OF BEES IN 

 COLONIES AFFECTED BY EUROPEAN FOUL- 

 BROOD^ 



By Aenold p. Stuetevant 

 Specialist in the Bacteriology of Bee Diseases 



CONTENTS 



Page 



Introduction 1 



Procedure 5 



Observations j: 8 



Summary of previous experiments 15 



Supplementary observations 17 



Study of naturally infected 



colonies 17 



Behavior of bees in cleaning 



contaminated cells 18 



Possible infection through 



queen 19 



Page 



Supplementary observations — Contd. 

 Distribution of introduced in- 

 fected material 20 



Age at which larvae are in- 

 fected 21 



Microscopical bacteriological observa- 

 tions 24 



Summary and conclusions 26 



Literature cited 28 



INTRODUCTION 



The brood diseases of bees cause annually large losses of bees and 

 consequently of the honey crop. The predominant attitude among 

 beekeepers has long been how best to eradicate an invading bee dis- 

 ease after the attack has been made. They depend upon this pro- 

 cedure, because little is known with any degree of certainty concerning 

 the natural conditions which might prevent or control the onslaught 

 of the disease. As a result of this attitude, much more importance 

 has been placed on the significance of apiary inspection and police- 

 power laws and of purely remedial treatment, the reasons for which 

 in many cases are imperfectly understood. But the old adage " an 

 ounce of prevention is worth a pound of cure " has yet to be refuted, 

 particularly with regard to beekeeping. In the realm of human 



^ A series of investigations was started in the spring and summer of 1918 by the 

 Office of Bee-Culture Investigations, Bureau of Entomology, for the purpose of making 

 an intensive study of European foulbrood of bees, primarily from the standpoint of 

 insect behavior in relation to the disease, correlated with the facts and practical 

 observations already known to the beekeeper. This paper, which was submitted for 

 publication January 13, 1919, is a preliminary report on the beginning of the In- 

 vestigation. 



134440°— Bull. 804—20 1 



