May 9, 1907 



391 



American Vae Journal 



Facts About Swarming of 

 Bees 



BY ADRIAN RETAZ 



Among the differeut kiuds of work 

 done by the European Societies of Agri- 

 culturists is now and then a study of 

 some subject connected with bee-keep- 

 ing. A series of questions or experi- 

 ments is submitted to the members 

 with the request to observe or experi- 

 ment during the ensuing summer, and 

 report. It is not obligatory on the 

 members, so only those who can do 

 take part. Sometimes when the ex- 

 periments requested involve a notable 

 expense of time or money, prizes are 

 offered to be given to those who have 

 done the best work. Among the api- 

 arists are found a good many who have 

 for a number of years studied some 

 subjects, or kept note, of whatever 

 happened in their apiaries. It is 

 through some arrangements of that 

 sort that the following information on 

 the swarming question was obtained, 

 principally through the efforts of Mr. 

 Thibault, Secretary of the Societe du 

 Bassin de la Meuse. 



Time of Swarming. 



In the country covered by the obser- 

 vations (northeastern part of France), 

 the swarming commences on an aver- 

 age date on May 28 and ends on June 

 20. The extreme dates have been from 

 May 17 to June 13 for the beginning, 

 and from June 6 to July 4 for the end- 

 ing. 



Duration : An average of 24 days. 

 It is understood that these dates refer 

 to the northeast part of France. Other 

 localities differ for different seasons. 

 For instance, in Belgium Mr. Mercier 

 gives for the swarming period from 

 May 20 to June 30. 



A full study of the swarming period 

 observed during 20 years in an apiary 

 of about 80 colonies is given. I will 

 not reproduce it here in full. Out of 

 the 20 years 3 were quite early, 10 near 

 the average, 5 late, and 2 very irregu- 

 lar so far as the dates and duration of 

 the swarming period are concerned. 



Taking all the information obtained 

 in consideration, the average number 

 of first swarms is put down in the fol- 

 lowing proportions : One-fifth in May ; 

 '2 from June 1 to June 10; '4 from 

 June 10 to June 20; 1-10 after that 

 date. Very few swarms come out be- 

 fore May 25, and very few after June 

 20, so the apiarist could go to the ex- 

 pense of close watching only between 

 these dates. 



Time of the Day. 



The limits observed are 8:15 a.m. and 

 and 4 p.m. in the extreme cases. On 



the total wuniber observed, ii percent 

 issued before 10 a.m., 22 percent be- 

 tween 10 and 12, 56 percent between 12 

 and 2 p.m., 1.^ percent between 2 and 3 

 p.m., and 2 percent after 3 p.m. 



The Weather. 



Needless to say that the bees will 

 not swarm when it is raining. To 

 what extent they may do it in cloudy 

 but not actually rainy weather has un- 

 fortunately not been noted. The wind, 

 when the weather is otherwise favor- 

 able, seems to have considerable in- 

 fluence. Evidently no swarm will issue 

 on a stormy day. But in fair weather 

 82 percent of the swarms issued during 

 no wind, or a light wind, and only 18 

 percent with a wind of medium 

 strength or more. 



As could be expected, the tempera- 

 ture has a paramount influence. 

 Eighty-nine percent of the swarms is- 

 sued when the temperature was above 

 68 degrees Fahr., in the shade, and 11 

 percent when below. One swarm is- 

 sued at a temperature of 59 degrees, 

 and the weather "nearly raining." 

 That was the lowest observation. 



It was also ascertained that by far 

 the largest number of swarms issue 

 when the barometer is high, but as the 

 state of the weather as to being more 

 or less cloudy or more or less warm was 

 not observed in connection with it, the 

 fact has but little value. 



Position of the Hives. 



Eighty-six percent of the swarms 

 issue when the sun shines on the en- 

 trance. It seems by that that the num- 

 ber of the swarms ought to be mate- 

 rially decreased when the hives are in 

 a shaded place. It is also stated that a 

 very large proportion of the swarms 

 issue from hives turned otherwise. 

 Unfortunately the number of hives 

 turned either way was not recorded. 

 As most of them are turned toward the 

 south, or nearly so, most of the swarms 

 come from such hives in at least the 

 same proportion. It would have been 

 interesting to ascertain this point 

 fully and find out whether the direc- 

 tion has any influence at all, and if it 

 has whether it is due to a higher tem- 

 perature, or to the actual shining of 

 the sun on the entrance, or perhaps 

 something else. 



Nattre of the Bees. 



The disposit 

 cessively with 

 in the same 

 varieties, and 

 vidual colonies 

 be deducted I 

 stated that in 

 of the colonic 

 bees. 



ion to swarm varies ex- 

 the different races, and 

 race with the different 

 even the different indi- 

 .. Nothing definite could 

 rom the reports. It is 

 France fully 99 percent 

 s are the common black 



In one of the apiaries reported (prob- 

 ably that of Mr. Thibault himself) 

 everything is recorded in detail since 

 1883. A study of the swarming in 

 that apiary brings out some interest- 

 ing facts concerning the vitality of 

 the different strains or varieties of 

 bees. Suppose an apiary of 100 colo- 

 nies to start with. These colonies and 

 the swarms produced by them will 

 swarm more or less every year. After 

 20 years, out of the 100 colonies 42 will 

 have disappeared entirely, not only 

 themselves, but the swarms that de- 

 scended from them in succession. 

 Eighteen will be represented by one 

 colony each ; 16 by 2 colonies each; 8 

 by 3 colonies each ; 4 by 4 colonies 

 each ; 4 by from 5 to '• colonies each ; 

 4 by from 10 to 19 ; 2 by from 20 to 29 ; 

 2 by 30 or more. It is also shown by 

 the tables given that the colonies hav- 

 ing left the largest number of descend- 

 ants are those which swarmed neither 

 very early nor very late. 



Age of the Queen. 



Out of 301 swarms 130 were from 

 colonies having swarmed the year be- 

 fore, and therefore had queens one 

 year old ; 61 from colonies having 

 swarmed 2 years before ; 44 from colo- 

 nies having swarmed 3 years before ; 

 66 from colonies having swarmed from 

 4 to 12 years before. These can not be 

 taken into account. Evidently nearly 

 all their queens had been superseded 

 and therefore their age can not be as- 

 certained. Some may have swarmed 

 unobserved. 



It would seem by these figures that 

 the age of the queens has but little to 

 do with the swarming question. This 

 was quite a puzzle to me. I woald 

 have thought that the colonies with 

 queens but one year old would have 

 swarmed considerably less than those 

 with older queens. At least that is 

 certainly the case in my apiaries. 



After considerable reflection on the 

 subject I came to the conclusion that 

 the discrepancy is due not exactly to 

 the " locality," but to the hives used. 

 In Europe most of the hives are yet 

 the old-fashioned straw hives. The 

 straw is all right enough, but the hives 

 are usually entirely too small. Now 

 when a colony is decidedly too crowded, 

 and the space is lacking for brood and 

 surplus, the colony will swarm if the 

 conditions of weather and honey-flow 

 are favorable, no matter how old or 

 young the queen may be. And, after 

 all, I do not know but that under such 

 circumstances the colonies with young 

 queens might swarm the moit, since 

 the young queens, being the best 

 layers, would get the colonies crowded 

 the soonest or the most. 



The Drones. 



Fifty-four percent of the swarms ob- 

 served came from colonies having a 

 great many drones, and 4b percent 

 from colonies having but few. Mr. 

 Thibault adds, however, that while it 

 does not make much difference whether 

 there are many or few drones, no col- 

 ony will swarm when there are none 

 at all. He also says that a queen 

 which is not defective in some way or 

 other will not lay any drone-eggs dur- 

 ing the year she has been reared ; that 

 means a queen less than a full year old. 



