A measure of some factors affecting the development of the honeybee colony

Transcription

1 University f Massachusetts Amherst SchlarWrks@UMass Amherst Dctral Dissertatins February 2014 Dissertatins and Theses A measure f sme factrs affecting the develpment f the hneybee clny Claytn Len Farrar University f Massachusetts Amherst Fllw this and additinal wrks at: Recmmended Citatin Farrar, Claytn Len, "A measure f sme factrs affecting the develpment f the hneybee clny" (1931). Dctral Dissertatins February This pen Access Dissertatin is brught t yu fr free and pen access by the Dissertatins and Theses at SchlarWrks@UMass Amherst. t has been accepted fr inclusin in Dctral Dissertatins February 2014 by an authrized administratr f SchlarWrks@UMass Amherst. Fr mre infrmatin, please cntact schlarwrks@library.umass.edu.

2 UMASS/AMHERST 3120bb 023D 3ST7 5 A Measure f Sme Factrs Affecting the Develpment f the Hneybee Clny Claytn Len Farrar This thesis is nt t be laned utside the library building. Fr this purpse, use the cpy in the department where the wrk f the thesis was dne.

3 A Measure f Sme Factrs Affecting the Develpment f the Hneybee Clny by C. L. Farrar Submitted as a thesis t the Faculty f the Graduate Schl in partial fulfillment f the requirements fr the Degree f Dctr f Philsphy at the Massachusetts State Cllege, June 1931.

4 NTENTS Page. ntrductin»..» l. Acknwledgments 5. Literature 4 V. Methds 5 1. nterpretatins 5 2. Measurements f Brd 6 3. Determinatin f Bees and Hney 8 a. System emplyed 8 "b. Bees per Pund 10 c. Weight f Brd Cmparisn f Wintering Practices Temperature Effect f Methds used n Experimental Clnies Strains f Queens 19 V. Climatlgical Cnditins * 20 V* Seasnal Cnditins, Pllen and Nectar Supply V. Brd-Rearing Clny Requirements fr Effective Brd-rearing rganizatin f the Brd Nest Develpmental Perid f the Wrker Brd Effects f Temperature n Brd -Rearing Seasnal nitiatin and Suppressin Seasnal Brd -Rearing Variatin in the Queen 1 s Daily Rate f Egg-Laying Daily Rates f Brd-Rearing nfluence f the Clny nfluence f Hney Flws and Stimulative Feeding nfluence f the Pllen Supply Swarming Races f Bees Hive Prtectin 58 V. Clny Develpment during the Active Seasn Variatins in Clny Strength Seasnal Changes» Length f Life f the Wrkers Death Rates Drifting Divisin and Uniting f Clnies Field Ppulatin 80

5 Page X- Wintering bject and Requirements Winter Cluster Habits Methds f Prviding Winter Prtectin Definitin f Terms used in nterpreting Data Results f Wintering Methds 95 a. 2-Stry Duble Walled r Buckeye Hives 96 b. 2-Stry Single Walled Hives - Uewspaper-Tarpaper Pack 99 c. 2-Stry Hives - N Hive nsulatin d. 2-Stry Hives - Tp and Bttm Pack. 101 e. 2-Stry Hives - Leaf Pack 102 f. 2-Stry Hives - Single Case-United Clnies 104 g. 2-Stry Hives - Single Case-United Yung Bees 105 h. 2-Stry Hives - Tw Clny Case 105 i. 2-Stry Hives - Quadruple Case 106 j. Mdified Dadant Hives - Three Clny Case 110 k. 1-Stry Hives - Cellar Wintering... ll 6. Summary f Wintering Methds 113 X. Summary 114 X» Selected Bibligraphy 121 X. Tables X. Plates

6 TABLES Page 1. The effect f age n the number f bees per pund 14 Daily variatins in egg-laying by queens heading nrmal clnies g 2» Classificatin f the frequency with which daily rates f brd-rearing abve 1000 ccurred during 518 bservatins, 1927 t * Frequency distributin f average daily rates f brd-rearing, 1927 t nfluence f hive insulatin n early spring brd-rearing 61 6, Mnthly summary f climatlgical data, Amherst, Massachusetts, April 1927 t ctber * Clny develpment data, Clny develpment data, Clny develpment data, Clny develpment data, Separatin f field bees frm yung bees The drifting factr shwn in clnies undisturbed during the eight weeks prir t the recrding f flight data , The drifting factr in the quadruple winter case Wintering data fr three seasns - 2-stry duble walled r buckeye hive Wintering data fr tw seasns - 2- stry single welled hives - newspaper-tarpaper pack Wintering data fr ne seasn - 2-stry single walled hives - n insulatin Wintering data fr tw seasns - 2-stry single walled hives - tp and bttm pack Wintering data fr three seasns - 2-stry Langstrth hives - leaf pack Wintering data fr tw seasns - 2-stry single walled hives - single clny case Wintering data fr tw seasns - 2-stry single walled hive - tw clny case» Wintering data fr three seasns - 2-stry single walled hives - quadruple case Wintering data fr tw seasns - mdified Dadant hives - three clny case » Wintering data fr three seasns - 1-stry single walled hives - cellar wintering Cmbined summary f wintering methds fr the seasns f , , and

7 PLATES Page 1. Brd-rearing curves: 1927, 1928, and Brd-rearing curves: 1930 (als "stimulative feeding") 3. Clny influence n brd-rearing, 1930 j 4» 4. Clny 169 influence n brd-rearing, , and 1930 * Clny develpment, 1927 * Clny develpment, i Clny develpment, Clny develpment, 1929 <;!;" Clny develpment, Clny develpment, Brd temperatures, single walled hive.! 12. Brd 177 temperatures, duble walled hive Winter temperatures, heavy pack and duble walled 179 ±4. Winter temperatures, duble walled hive Winter temperatures, shwing effect f a sudden drp in temperature n clny 59, single walled hive; and clny 60, well insulated b-ive ; lgl 16. The effect f a sudden drp in utside tempera-* ture n the hive and cluster temperatures, clny 59, 2-stry single walled hive The effect f a sudden drp in the utside temperature n the hive and cluster temperature clny 60, well insulated hive Plan f apiary as affecting the drifting prblem; als shwing wind prtectin; als phtgraphs f packing methds Diagrams f packing methds shwing cluster lcatin at the beginning f the winter perid 185

8 NTRDUCTN The successful utilizatin f the Hneybee fr either hney prductin r pllinatin, necessitates that strng clnies be develped fr specific prductive perids. Clny develpment may be limited r enhanced by the time available between the perid f inactivity and that f prductin, by the ptential strength f the clny at the beginning f the develpmental perid, by seasnal cnditins during this perid, r by management. Bees are creatures f instinct since they behave the same under similar envirnmental cnditins* The cnditins affecting their behaviur ccur bth inside and utside the hive* A knwledge f bee behaviur is the nly reliable guide fr the beekeeper in attempting t crrelate thrugh management, the develpment f clnies with the cnditins f the lcality. The purpse f the wrk herein presented has been t measure and evaluate factrs f envirnment which affect the develpment f the nrmal clny. Beekeeping as an art is extremely ld; as a science it is cmparatively yung. Therefre, its literature still cntains an admixture f pinins r unrefined "facts* incrprated with established principles f bee behaviur and methds f management*

9 2 The influence f reginal differences n methds f practice has given rise t different interpretatins f the imprtance f certain factrs, depending upn their prminence in a particular lcality* There is evidence that different methds f practice are in part respnsible fr the differences attributed t regins. The uncertainty f climatic cnditins, the time and intensity f pllen prductin and hney flws which are determined by lcality and seasn, tgether with the cmplexity f the clny s rganizatin d nt permit a sharp separatin f factrs fr study* The direct entrl f any ne factr wuld in many instances intrduce abnrmal cnditins having a greater influence n the clny than the factr measured. This treatise is cnsidered in three sectins with an attempt t establish their interrelatinships. First, Brd-rearing which is the basis fr clny develpment. Secnd, Clny Develpment which during the active seasn must be crrelated with seasnal cnditins that affect the time f the hney flws. Third, Wintering which is necessary t prvide clnies capable f rearing brd at the beginning f the develpmental perid and which determines the level f strength frm which they must be develped t prductive strength.

10 AC WLEDGMENTS 3 t ia with greatest pleasure that dedicate this wrk t my friend and frmer teacher f Beekeeping, J. H. Merrill, Ph. D», Massachusetts Agricultural Cllege, t was under him as his student assistant fr three years at the Kansas State Experiment Statin that became interested in this prblem and have endeavred t expand the study alng lines which he wuld have undubtedly cntinued had his physical health permitted him t remain in active wrk. Dctr Merrill has given me many helpful suggestins and has been a cnstant surce f encuragement. wish t express my sincere gratitude t my assciates in the Department f Entmlgy fr the active interest at all times in the prgress f this prject. we much t Prfessr H. T. Fernald fr his valuable suggestins fr the executin f these studies during the first three years while he was directing my thesis. am particularly indebted t Prfessr A» X* Burne fr his untiring assistance in ging ver the manuscript with me t insure clearness f fact. Lastly, we mst t my dear wife whse cnstant encuragement and aid played n small part in making pssible the cmpletin f this wrk.

11 LTERATURE 4 The literature relating t Clny Develpment as viewed by the writer in this paper, ia inexhaustible. Hwever, references directly relating t the measurement f factrs determining the rate f clny develpment are nt numerus and usually prvide nly a single cntact with sme ne sectin f the whle prblem. The necessary interpretatins are therefre made in the text f the paper by citing these references when they have a direct bearing n an immediate phase f the subject. The fllwing standard references setting frth principles f bee behaviur and management while nt directly used in this wrk, have had an imprtant and valuable influence n the develpment f present cmmercial practices. Rt (59) has maintained an encyclpedia f beekeeping thrugh many editins beginning in 1877, which has prved f great value in advancing cmmercial practice. Phillips (56) has given particular strength t cmmercial practices thrugh emphasis n bee behaviur r an understanding f the clny and its rganizatin, the life f the individual in relatin t the clny, and the cycle f the year. Demuth (7,8) has successfully enumerated the fur main

12 pints essential t the prductin f surplus hn and has interpreted the balance f cnditins gverning clny develpment, swarming, and hney strage which he adequately characterized as ""Clny Mrale** the METHDS Hrmal clnies f full strength were used thrughut these studies except where therwise stated. The writer's use f the term *3rrmal clny f full strength* refers t ne capable f maintaining and reprducing itself which wuld be accepted by practical beekeepers as either a medium, average, r strng clny fr a particular seasn f the year. The standard 2-stry, 10-frame Langstrth hive r its equivalent has been accepted as the minimum equipment necessary fr full clny develpment. The results f Slan (45), Merrill (28), and thers, tgether with the experience resulting frm cmmercial practice, warrants the use f this hive. The clnies were lcated where they were expsed t full sunlight, sheltered frm prevailing winds, and spaced in such a manner as t minimize the factr f drifting t & pint acceptable with cmmercial practice. The factr f drifting prved t be far mre imprtant than previusly recgnized. A limited grup f clnies t serve as a check against this prblem were placed in semi- islated lcatins t

13 6 eliminate drifting. t seemed desirable t cntinue mat f the bservatins under accepted cnditins f practice. Peridic measurements f the amunt f brd, the number f bees, and the number f punds f hney cntained in each clny were made fr the purpse f evaluating clny cnditins. Measurements f Brd Measurements f the number f square inches f sealed brd were made at regular 12-day intervals; the perid representing the average length f this stage* All brd develped by the clny can thus be measured befre it becmes transfrmed int adult bees. bservers f brd-rearing previus t Slan (45) measured the brd in all stages at 21-day intervals. Such a plan intrduces a variable errr f cnsiderable magnitude. This is due t the difficulty f readily detecting eggs and early stage larvae. Furthermre, Merrill (34) has shwn that as many as 50 per cent f the eggs laid may fail t develp, thugh such a lss is nt typical. n a nrmal clny, a brd which reaches this stage is reasnably sure t emerge. The writer has fund n mrtality f sealed brd that had passed the early pupal stage when allwed t emerge abve a strng clny. Gderham (18), hwever, reprts that where sealed brd f all stages is remved frm the cluster and allwed t emerge fr 12 days in incubatrs r abve strng clnies, the

14 7 mrtality ranged frm 10 t 25 per cent and even greater when water t present. raise the humidity was nt The number f cells f brd was btained by multiplying the square inches measured by 27.4, the factr representing the number f cells per square inch. Each cmb cntaining sealed brd was placed in a frame marked ff int square inches by crss strings. Allwances fr incmplete squares f brd were made prgressively as each area was measured. The bserver fund by frequent recunts that this methd gave an errr nt exceeding ne square inch per aide fr the average frame. T further check the accuracy f this methd, a series f cmbs prviding mre than a thusand square inches f brd were measured in the usual manner. The number f sealed cells were then cunted directly with the aid f a unit tabulatr. By dividing the number f cells by the square inches measured, 27.4 was btained as the number f cells per square inch. Actual cunt f cells in definite areas fr a number f cmbs shwed variatins f a few tenths in each directin frm this factr. T avid rbbing, the brd cmbs were usually taken inside the building fr measurement.

15 8 These were usually away frm the clny between 10 and 20 minutes. The lss f heat during this shrt interval was very small and n signs f chilled brd were encuntered under these methds. Determinatin f Bees and Hney The clnies f a series t be determined were screened the night previus with a guard cvering the full width f the entrance that prvided a clustering space apprximately 2.5 inches deep and 10 inches high. Strng clnies during perids f high temperatures were prvided with the Miller bttm bard, allwing a 2.5 inch entrance instead f the usual 7/8 inch. High grade Fairbanks scales weighing readily t.5 f an unce were leveled at the rear f the hive n a metal hive cver. Empty hive bdies equivalent t the number ccupied by the clny were kept cvered with tw hive cvers. These were weighed and placed n a wheel barrw ready t receive the frames taken frm the clny. The clny with the bees enclsed was next weighed. A bttm bard and tw hive bdies cvered with a damp burlap bag were placed n the clny*s hive stand t receive the bees. The clny was then set at right angles t its hive stand

16 . 9 fr ease in manipulatin- The cver, inner cver, hive bdies, entrance guard and bttm bard were placed n the scales as remved frm the clny in rder t determine the weight f the hive parts. As the frames were remved, they were quickly scanned t lcate the queen and the bees were then shaken r brushed int the empty hive n the riginal stand. The degree f shaking r brushing f the bees was determined by the presence r the absence f nectar. When nectar was nt present, mst f the bees were disldged by shaking and the few remaining were brushed ff; when nectar was present, all the bees were brushed ff. When the queen was lcated, she was placed in a Miller intrducing cage just inside the entrance f the hive int which the bees were shaken, in rder t give her maximum prtectin. n fllwing this plan, nt mre than tw per cent f the queens escaped the bserver. Practically n queens were lst r injured due t these manipulatins. The hive bdies cntaining the frames remved frm the clny were kept cvered with a damp burlap bag t prevent rbbing. When all the cmbs were free f bees they were clsed with the prper cver fr weighing

17 10 The hive parts nw n the scales were then weighed* They were remved and the equipment cntaining the cmbs f hney and brd weighed. By subtracting the riginal weight f this equipment frm the latter* the weight f the frames plus the hney and brd was btained. The weight f the cmbs added t that f the hive parts and subtracted frm the riginal weight f the clny gave the weight f the bees remved. Determinatin f Bees per Pund The bees frm all parts f the clny are thrughly mixed as they were remved frm the frames and clustered n the inner walls f the tw empty hive bdies lcated n the riginal stand. A sample frm this cluster cntaining apprximately 500 t 700 bees was then taken in a bx designed fr gassing. A screened pening in this bx was placed in cntact with the muth f a pint jar cntaining calcium cyanide, until the bees appeared lifeless. The sample was immediately weighed t the nearest centigram n a chemical balance; then spread n a paper, divided int rws 3 t 5 bees wide, and their exact number determined with the aid f the unit tabulatr. The ttal weight divided by the number f bees in the sample gave the average weight per bee in milligrams.

18 11 The number f milligrams cntained in a pund divided by the average weight per bee gave the number f beea per pund. The number f punds f bees remved frm the cluster when multiplied by this factr gave the number f bees cntained in the clny. The methd used during 1927 fr btaining the number f bees per pund differed frm the abve. ne r tw punds f beea were secured in a bx equipped with a funnel tp and then weighed t 1/64 f a pund befre and after liberating 500 beea thrugh the funnel. The first methd described prved much mre rapid and checked s clsely with the latter that it was used entirely after the first summer. Less accuracy in weighing f the latter, tgether with lss f weight by bees while in the bx wuld suggest that the gassing methd was the mst reliable. The slight expsure t hydrcyanic acid gas necessary t render the bees inactive apparently did nt seriusly injure them. They usually revived and entered the clny within 30 minutes. Beea anaesthetized with cyanide d nt regurgitate hney frm the hney stmach as d thse treated with chlrfrm r ether, a cnditin which wuld make weighing difficult. Beea which are at first nly

19 12 partially anaesthetized with weak cyanide are nt subject t a cyanide charge f maximum strength fr perids f three t five minutes where if given a strng charge at first, they are rendered inactive in 15 t 30 secnds. A series f cage experiments t test the effects n the life f the wrkers, using cyanide and chlrfrm and cntrlled by bees frm the same sample which were nt gassed, shwed that bees treated with cyanide revived and lived as lng as the cntrl bees r an average f eight days under average rm cnditins; in the absence f light but under similar temperatures, they lived mre than tw weeks. Ehe bees treated with chlrfrm revived in abut the same time but died in 36 t 48 hurs. H bservatins were made n the activities f bees gassed with cyanide after they entered the clny. Desbrugh (9) was ne f the first investigatrs wh measured brd and bees althugh his clny was extremely small. He estimated the number f bees n the basis f 2000 wrkers in a pint s that his clny cntaining three pints f bees was cnsidered t have a ppulatin f Mst investigatrs f clny ppulatin during recent times have assumed that there were 5000 bees in a pund, having accepted the cnclusin f Kns (Rt, 57). Ebert (13) used

20 13 10 bees per gram r 4540 bees per pund. The acceptance f 5000 bees per pund in estimating the number in a clny» intrduced an apprximate errr f 20 t 30 per cent althugh the errr will vary frm 10 t 40 per cent, depending upn the clny and cnditins under which the weights were taken. The methds used by Kns did nt give the true average weight fr all bees in the clny. His results apprach the average weight f field bees. The average number f bees per pund fr an entire clny was fund t vary betwen 2800 t 4800 due t differences in size f bees, the prprtin f yung bees t field bees, drnes t wrkers, the effect f the hney flw, amunt f hney in the hive, seasn f the year, and the temperament f the bees at the time f weighing. The majrity f determinatins gave numbers ranging between 3500 t 4000 bees per pund. Determinatins fllwing the end f brdrearing generally gave heavier bees, while thse taken when the clnies were lw in stres gave light weight bees. Thrugh the use f reasnably gd cmbs and the practice f decapitating mst f the drne brd when making the 12-day cunts very few drnes (these require 14 t 14.5 days in the sealed stage) were permitted t develp in the experimental clnies.

21 14 The fllwing tabulatin represents the difference in the weight f emerging bees* nurse beea, and field bees fr a typical determinatin. Table 1. The Effect f Age n the fumber f Beea per Pund. Data: September 8, Clny Emerging Beea Yung Beea Field Beea Mg. Beea Mg. Beea Mg. Beea per per per per per per Bee Lb. Bee Lb. Bee Lb. 3? The field beea referred t abve were aeparated frm the yung beea by mving the clny aix feet t the rear. A new hive waa placed n the riginal atand f each clny t receive the returning field beea. Each hive cntained a frame f unsealed brd and hney t keep the returning beea cntented. Weight f Brd The amunt f hney in the hive was estimated by subtracting.9 punds fr each frame plus the estimated weight f the brd frm the grss weight f

22 15 all cmbs. The brd weight was estimated by multiplying the daily rate f brd-rearing by a cnstant This cnstant was calculated frm the average weights f brd fr all stages (egg t emergence) frm data given by Kelsn, Sturtevant and Lineburg (45), multiplied by the number f days required fr cmplete develpment. This was then cnverted frm metric t avirdupis units. B satisfactry methd fr estimating the weight f pllen was fund, but since pllen may be cnsidered even mre valuable t the clny than hney, it is nt incnsistent t cnsider hney and pllen tgether. The specific changes in the hney flw were btained by taking the daily changes in weight f a full strength clny kept n scales thrughut the active seasn. Merrill (30) and Hambletn (19) have shwn that the respnse f different clnies t hney flw cnditins are similar, differing nly in degree. Merrill's results were btained frm the daily changes f a series f clnies, while Hambletn shwed, by cmparing the hurly changes fr tw clnies ver an extended perid, that the similarity f respnses was equally characteristic fr shrt perids.

23 16 Cmparisn f Wintering Practices The methds emplyed in wintering were thse which varius grups f beekeepers have maintained t be the mst successful. All clnies were prvided with ample stres f gd quality. Since the hney stred in this lcality was never entirely free f hney dew, at least ten punds f sugar was fed t each clny t prevent dysentery. The ptentialities f clnies were measured in the fall and again in the spring, in respect t the number f bees, age f bees, amunt f brd and stres fr the purpse f evaluating wintering methds. The plans f giving winter prtectin are phtgraphed and diagrammed, Plates 18 and 19. Tw prblems became evident frm the first years recrds, which have a very imprtant bearing n the interpretatin f changes fund in clny strengths. First, that drifting may disturb the balance in clny strengths far mre than the methd f insulatin. Secnd, that the death rate f bees in the fall is s high that it becmes necessary t limit the cmparisn between clnies, t thse taken n practically the same day. Similarly, in the spring the clny increases rapidly because f brd emergence. The difference f ne week in taking recrds f tw clnies may ffset any difference due t the methd f insulatin.

24 17 ias r gain in clny ppulatins is expressed in percentages rather than in number f bees as emplyed by Merrill (25, 26, 28). A lss f 5000 bees frm a clny cntaining 15,000 bees is mre serius than frm ne cntaining 25,000. n the ther hand, a gain f 5000 wuld be f greater value t the smaller clny. Clnies shwing the least percentage lss in bees and ptential bees r the greatest percentage gain are used as the standard fr cmparisn. The cnsumptin f stres is relative, being affected by cnditins f wintering but mst nticeably by the amunt f brd reared during the spring perid. Temperature Temperatures cited thrughut this paper are given n the Fahrenheit scale. Temperature measurements were made by means f therm-cuples, first emplyed fr temperature studies in the hneybee clny by Phillips and Demuth (50) The arrangement and style f equipment used were similar t that described in detail by Wilsn and Milum (65) except that 118 and 134 therm-cuples were distributed respectively in tw full strength 2-stry clnies as shwn in plates 11, 12, etc., in cntrast t 44 therm-cuples used in each 1-stry clny by them.

25 18 The Effect f Methds used n Experimental Clnies The experimental practices emplyed thrughut this wrk did nt destry the nrmality f the clnies under bservatin except where that was the direct bject f the manipulatin. The peridic 12-day bservatins permitted the readjustment f the brd nest and strage space t permit maximum develpment at all times. The evidence that this was attained is indicated by the fact that the clnies reached maximum strength when cmpared with the best clnies in cmmercial apiaries in the white and sweet clver regins, and because their prductin during the hney flws averaged vastly superir t the remaining clnies in the yard maintained fr class purpses. The brd nest was unrestricted at all times. After measuring the brd areas, thse frames cntaining mstly unsealed brd were placed n the lwer hive bdy; sealed brd and empty cmbs in the secnd; empty r partially filled super cmbs in the third; and partially filled r full super cmbs in furth r fifth as required. This readjustment f the brd nest was emplyed t stimulate maximum develpment, t btain full use f all the cmbs, and t prevent the develpment f the swarming impulse. n this respect the methds used differed frm Hlan (45) wh prvided

26 19 ample ram but did nt readjust the brd nest at any time. The brd nest is the center f all clny activities. The mst prnunced tendency fr expansin is upward. The emerging f the sealed brd abve gives rm fr upward expansin f the brd neat. Hney ia atered mst freely just abve the brd. A barrier f hney between the brd neat and empty strage space is nt cnducive t clny expansin and under such cnditins, strng clnies are quick t start swarm preparatin. Strains f Queens t has nt been the purpse in these studies t evaluate strains f bees^ut rather t study the develpment f clnies under recgnized cmmercial standards. The queens purchased were btained frm well knwn breeders. All queens nt therwise designated were f apparently pure talian stck althugh sme prduced hybrid bees because f mis-mating. When dealing with specific clnies in discussing the results presented herein, reference will be made t the strain r race, age and the methd f handling the queen heading each clny. Purchased queens will be designated as Strain A, B, C, D, E, P, r G, the letter symbl referring t the breeder frm whm the queens

27 20 were btained. identified by the Queens reared lcally will be clny number and atrain frm which, they were bred, CLLMAELGCAL NDTN A mnthly summary f climatlgies! cnditins present at Amherst is included fr the perid f these bservatins, Table 6. Climate affects the hneybee clny in tw ways: First* in the direct respnse f individual bees and the cluster as a unit t the influence f temperature, misture, light, and winds; Secnd, in an indirect respnse as these factrs affect plant develpment and thus gvern their pllen and nectar supply. SEASNAL NDTNS, PLLEN AND NECTAR SUPPLY Plants came ut f the drmant state abnrmally early in the spring f 1927, due t high temperatures and lack f rainfall. Pllen was available frm March 16 thrughut mst f the active seasn. Sft maples prduced mre nectar than was used in brdrearing during the middle f April. The temperature was belw nrmal the last cf April and during mst f May s that fruit blm ccurred frm May 5 t 20, r practically nrmal, thugh very little nectar was btained. Small amunts f nectar were gathered frm

28 21 mixed surces during early June, This was fllwed by cnsiderable hney dew between June 10 and 19. heavy flw frm white and alsike clver began June 21 and this was supplemented in early July by basswd. A Climatic cnditins were very favrable fr nectar secretin and bee activity until the flw was ended the middle f July by severe thunder shwers, fllwed by general rains. H further surplus nectar was gathered until a light glden rd flw, September 12 t 18, The seasn was cnsidered mderately gd fr hney prductin. The *winter» perid f may be characterized as mild; cleansing flights were frequent. The rain fall was excessive during H v ember and December temperatures were well abve nrmal until March and April when they fell belw. The snw fall was unusually light and did nt remain n the grund fr any extended perid. n the spring f 1928, pllen became available during late March and lasted until the middle f April, a cnditin which permitted the clnies t expand their brd neat. Subsequent lw temperatures, wind, rain, and snw prevented further cllectin f pllen until May 2. Fruit blm extended frm May 13 t 26, three days f which the scale clny shwed a gain f frm 3 t 6 punds. The rain fall was excessive during

29 22 June, July, and August s that the hney flw fr the eeaan was practically nil, except fr a very light flw the first tw weeks f July. A glden rd flw permitted the strage f 12 t 15 punds between September 5 and 17. The seasn was decidedly unfavrable fr the bees and cnsiderable sugar had t be fed in preparing the clnies fr winter. The winter" perid f was mre nearly nrmal than the previus year. During mst f the winter, cnsiderable snw remained n the grund. The mean temperature fr December was 4.3 P. abve npaanal while January was 1.3 F. belw. The minimum temperature fr the winter was 11 belw zer. Spring develpment was nrmal in 1929, there being enugh high temperature t ffset the cl rainy days. Excessive precipitatin fell during April and May. Fruit blm extended frm May 5 t 20 with a creditable surplus f nectar being cllected frm apples May 12 t 20. Cnsiderable hney dew was cllected between May 22 and June 10, permitting the scale clny t gain 38.5 punds. High temperatures, an abundance f sunlight, and lack f rain, fllwing the wet spring prvided favrable cnditins fr a heavy hney flw chiefly frm alsike clver, which began June 11 and lasted until July 12 permitting the scale clny t gain punds. The drught persisted and glden rd failed t secrete nectar in September.

30 23 The "winter" perid f was practically nrmal except that lw precipitatin waa evident thrughut the fall. The lw temperatures f January and February was mre extended than during the previus year. Hwever, these were ffset by temperatures abve nrmal during ther prtins f bth mnths s that the respective means were abve nrmal. The spring f 1930 was characterized by ita extremely rapid develpment resulting frm abnrmally high temperatures beginning the first f May. Lack f misture was evident thrughut the spring until after the middle f May. Fruit blm prduced nectar frm May 2 t 13, during which time the scale clny gained 55 punds; peaches, plums, cherries, and apples all secreted nectar in abundance. The previus dry fall tgether with a dry spring left the clvers in pr cnditin fr nectar secretin s that practically n nectar was btained frm them. Hney dew was cllected thrughut mst f June and a small amunt f nectar during a few days f that mnth. were made between July 18 and August 7. Small gains Glden rd and aster were abundant but the nectar cllected between September 12 and 21 was chiefly frm aster.

31 24 BRD-HEARNG Brd-rearing is the basis fr clny develpment. The amunt f brd reared by the clny determines bth the rate and limits f its develpment. t is imprtant that the clny attain a maximum wrking frce by the beginning f the main prductive perid. The tendency fr beekeepers t ver estimate the clny»a capacity fr brd-rearing has been prevalent since Berlepsch in 1856 (Hlan,44) btained 3021 eggs frm a queen during 24 hurs. The reprt f this reerd brught frth numerus exaggerated estimates and sme f these reached as high as 6000 eggs per day fr extended perids. By the repetitin f such unfunded assumptins, many beekeepers have been misled by their enthusiasm and have expected their clnies t reach a prductive strength in t shrt a time. n the ther hand, a knwledge f the limitatins and the factrs gverning brd-rearing will give the beekeeper pprtunity t prperly crrelate the develpment f clnies with cnditins in his lcality. Clny Requirements fr Effective Brd-rearing The replacement f the cmmn black German bee in Nrth Jtaerica, beginning abut 1860, by the intrductin f talian queens gave such marked

32 imprvement in the prductin f clnies that many 25 beekeepers still maintain that a yung talian queen will insure a strng clny whenever it is needed. A prlific laying queen is ne factr essential t effective brd-rearing. The number f eggs which she will lay and the amunt f brd reared are determined by the strength f the cluster, the pllen and hney supply inside the hive, the cnditin f the hney flw, the number and the psitin f available cells fr expansin, and the clny mrale. rganizatin f the Brd Best Brd-rearing begins in the center f the cluster when the temperature at that pint is raised t apprximately 93, prvided that bth pllen and hney are available t the bees. This may ccur even befre the first spring pllen and nectar is cllected. The brd nest is typically arranged in spherical frm, the different stages being distributed in cncentric rings in the separate cmbs f the brd nest with apprximately the same brd area being maintained n bth sides. men the area is increased in the first cmb, smaller areas are filled in cmbs n either side apprximately ppsite the center f the larger area. As these areas increase, additinal cmbs are included by a similar expansin alng the radii f the spherical brd nest. The tendency t expand the brd nest

33 26 upward insures the brd nest being in clse cntact with the hney supply and ne which is favred by the higher temperatures abve. The surplus pllen is placed immediately surrunding the entire surface f the spherical brd nest in a rather unifrm layer r band. Surplus hney is placed largely abve and t the sides, but never belw, fr permanent strage. Where the cmbs t either side f the brd nest d nt cntain sealed hney, the bees tend t mve hney t the side f the cmb that faces the brd nest, ften leaving the ppsite side entirely empty and placing hney in the next cmb n the side facing the brd neat. H bject fr this behaviur has suggested itself thugh it has been repeatedly bserved in the clnies under bservatin. The exact shape f the brd nest will be limited by the shape f the frames. The brd nest is the center f all clny activities and there is a prnunced tendency tward an upward expansin. The brd nest is kept in clse prximity t the fd supply and when this is increased bth pllen and nectar are stred as clse t the brd as pssible. Empty cmbs belw the brd r abve a barrier f several inches f sealed hney are nt used effectively fr either the expansin f the brd nest r strage f hney. This fundamental rganizatin must be recgnized if ptimum cnditins are t be prvided fr the expansin f the brd nest r the strage f hney.

34 27 Develpmental Perid f the Wrker Brd The term brd includes all the immature stages preceding the emergence f the adult bee. Unsealed brd includes the egg r embrynic stage and the larval feeding stage. Sealed brd includes a prtin f the larval stage, the pupal stage, and a few hurs f the adult stage prir t emergence. The egg is depsited in the base f the cell by the queen and nrmally requires 72 hurs fr incubatin. Lineburg (23) states that just befre the egg hatches nurse bees supply a small quantity f ryal jelly abut the egg and that the misture frm this fd is apparently necessary befre the larvae can break thrugh the chrin r egg shell. Accrding t Sudek (61) ryal jelly is a highly nitrgenus secretin prduced by the pharyngeal glands f nurse bees. The newly hatched larvae flat fr frm 2 t & days n a small mass f ryal jelly supplied by the nurse bees. At this time the type f fd and manner f feeding is altered frm mass feeding f ryal jelly t prgressive feeding during an additinal 2 t 3 days, when the grwing larvae receive chiefly pllen and hney. ffelsn, Sturtevant, and Lineburg (43) have stated that apprximately 10,000 visits frm nurse bees are given each individual between the depsitin f the egg and the sealing ver f the cell, during which time there is an increase in weight frm apprximately.132 mg. t

35 28 apprximately 155 mg. After sealing, 1 t 2 days are spent in spinning a thin ccn, and 2 days f quiescence befre the final larval mlt prduces the pupa; transitin frm the pupa t the adult takes place frm 7 t?- days later. The ttal perid frm egg t emergence is generally cnsidered t require 21 days. The wrk f Berthlf (3) n the mlts f the hneybee larva indicates that sealing f the brd takes place 8 days after egg laying rather than the usually accepted perid f 9 days. Milum (40) states that the temperature within the brd nest determines the length f develpmental perid which may range frm less than 20 t mre than 24 days but that per cent emerged within an average perid f 20.5 days; the majrity being sealed between the eighth and ninth day. Stabe (63) fund that the maximum weight f the wrker larvae was reached in 5 days. Since the length f these stages have an imprtant bearing n the brd bservatins used as a basis fr calculating the bees that shuld be in the hive at a certain time, the fllwing bservatins were made n the stages f brd develped by three full strength clnies. Each queen was cnfined t a single empty brd cmb fr 24 hurs in a cmpartment enclsed by queen excluder zinc in the center f the cluster. 3y exchanging cmbs every 24 hurs, the time f hatching, the beginning and end f sealing, and the beginning and end f brd emergence was nted. Twelve days after a

36 29 frame was taken frm the egg-laying cmpartment,, it culd be reinserted since it was fund that even the slwest develping brd wuld emerge befre the new cycle f brd was ready fr sealing* By using nly 12 frames, the brd nest was maintained quite cmpact as is typical in the nrmal brd neat. t was fund frm this study that fully 95 per cent f the brd was sealed in 8 days and that it emerged 12 days frm the time f sealing, making a ttal f 20 days frm the time f egg-laying. n thse cases where the brd cmbs were placed t the utaide f the cluster next t the hive wall, the ttal perid varied between 20 and 23 days (See temperature effects n brd-rearing}* Hwever, brd which required 9, 10, r 11 days in the unsealed stage did nt have the sealed stage crrespndingly increased. A slightly greater number are sealed in less than 8 days and emerge in less than 20 days frm egg-laying than exceed these limits. Hwever, this variatin des nt appear t exceed mre than 1 t 4 hurs, a perid shrter than can be accunted fr when cmparing the effects f brd-rearing rates n clny develpment. The use f the 12-day interval, based n the length f sealed brd stage therefre seems entirely lgical fr the crrelated studies treated later under "Clny Develpment.*

37 » ) 30 Effects f Temperature n Brd-Rearing Phillips and Demuth (50) shwed that brdrearing nrmally tk place at a cluster temperature abut 93 * They pinted ut the danger f unseaanal brd-rearing resulting frm undue winter activity prduced by pr methds f wintering, a cnditin frequently brught abut by lw quality stres which result in excessive accumulatin f feces. Milum bserved that variatins in temperature f the cluster hastened r retarded brd develpment. Dunham (11 by maintaining a clny in a cnstant temperature case at apprximately 93, fund much less brd was develped and that this was badly scattered; upn exchanging the psitin f this clny with the check, the cnstant external temperature f 93 suppressed brd-rearing in the latter while the riginal test clny re-established a nrmal brd nest. Retarded brd- rearing under such cnditins suggests that the nrmal activity f the nurse bees in brd-rearing is sufficient t appreciably raise the temperature abve that f the surrunding air and under the abve artificial cnditins, the prblem f lwering brd temperature by clny activity was apparently mre difficult than the prductin f heat and maintenance f prper temperatures

38 31 Daily temperature recrds btained frm the full strength 2-stry clnies during April, May, and June, and peridic recrds thrughut the remaining prtin f the active seasn just previus t the examinatin f the brd nest verify the results f previus wrkers that brd-rearing nrmally takes place at a temperature f abut 93. Egg- laying expanded t a new area in the hive after the temperature rse t abut 93 althugh this area was ccasinally allwed t drp as lw as 78 after the eggs were laid* Milum bserved that eggs ccupying lw temperature areas were apparently uninjured but that their perid f develpment was appreciably lengthened. A full strength clny during the active brd-rearing perid nrmally maintained a temperature in the brd nest ranging between 92.5 and 96*5. The temperature at any pint was bserved t vary within this range, but usually nt mre than frm a few tenths t ne r tw degrees* Brd cmbs placed next t the hive wall were nt maintained at full brd-rearing temperature and the develpment f the unsealed stages was materially retarded. Hwever, the queen in a nrmal clny prvided with tw brd chambers avids the use f utside cmbs.

39 32 Hurly fluctuatin in brd temperatures were bserved which ccasinally rse abve 97 with a maximum f 100. The first strng flight between 7 t 8 A.* and a heavy return f bees at abut 5 t 6 P.M. were usually accmpanied by a temprary temperature* ri3e in The brd areas are s definitely defined by brd temperatures within the abve mentined range that in the nrmal clny (See plates 11 and 12) a brd-rearing cluster may be cnsidered as characteristic as the brdless winter cluster defined by Phillips and Demuth (50 )* Temperatures frm 15 t 20 degrees lwer were frequently bserved within a few inches f the brd area n the same cmb. The heat riginating frm the metablism f the brd itself n dubt plays an imprtant part in aiding the nurse bees in keeping the temperature f the brd-rearing cluster unifrmly high. The prnunced tendency fr the queen t expand her brd neat upward is apparently the result f a temperature respnse. Whenever empty cmbs are made available directly abve the active brd nest, a gradual rise in temperature takes place between these cmbs surfaces, a cnditin which is nt nticed when cmbs are made available t either side r belw. The temperature usually reaches 93 within 3 t 5 days and the queen immediately expands her egg-laying t the

40 33 cmbs abve (except in the case f newly drawn cmbs)* This situatin is in harmny with the principle that warm air rises. The queen's respnse t this temperature stimulus prvides a definite principle f management applicable t the 2-stry brd chamber, namely the peridic reversal f brd chambers. This establisiea ptimum cnditins fr the expansin f the brd nest, ne f the cnditins essential fr the eliminatin f the swarming impulse. Seasnal nitiatin and Suppressin f Brd-Rearing A& just shwn, the rearing f brd is definitely crrelated with a particular temperature range f which 93 is typical* The cmbinatin f factrs which initiates nrmal brd-rearing in the spring and suppresses it in the fall have nt been clearly analyzed. Any activity f the cluster which will raise the temperature within t apprximately 93 fr ^perid f hurs is generally accmpanied with egg-laying. f bth pllen and hney are available in the hive, brd-rearing nee started in late winter will usually be cntinued withut interruptin. Theretically, the bees shuld expend the least pssible energy during the winter perid in rder t prlng their lives, and then resume brd-rearing in the spring when fd, particularly pllen, becmes available. The cllectin f pllen r nectar in the field, accmpanied by its strage in the hive wuld

41 34 cause the cluster t be active enugh t develp brd temperatures. it is dubtful whether many clnies wait fr the activity f fd cllectin t initiate brd-rearing in the spring. Phillips and Demuth, and thers, have fund that a clny which is restless frm the accumulatin f" feces and lng cnfinement increase the cluster temperature t the pint f brd-rearing. Merrill (33) suggested a thery that whea the cluster is subjected t a sudden drp in temperature fllwing a warm perid in which the cluster is temprarily brken, that the bees ver d the generatin f heat while refrming the cluster until brd temperatures are reached. The writer, January 1929, bserved a sequence f temperature fluctuatins fllwed by brd-rearing in the clny under bservatin which agreed exactly with this thery althugh n cluster temperatures were recrded at the time. Temperatures presented in plates 16 and 17, hwever, d nt supprt this thery. Brd temperatures btained January 20, plate 17, previus fllw a rise in temperature instead f the drp; als brd temperatures have been bserved n several ccasisns t accmpany a shrt flight f bees during the winter perid, but these were in n case maintained after the clny quieted dwn as the utside temperature became unfavrable fr bee flight.

42 35 Egg-lay ing was initiated within 24 hur a (January 1930) by inserting a heater filament insulated by glass tubing bent in the f rm f a which prvided abut 1.5 inches space between the parallel lines f the tube and extended 6 inches dwn int the center f the cluster. This was cntrlled by a thermstat t maintain a temperature f 93 and equipped with suitable resistance t avid a filament temperature exceeding 100. Brd-rearing nce begun culd nt be stpped by remving the brd r caging the queen temprarily, a cnditin which greatly limits the pprtunity fr the use f this type f equipment. Brd temperatures usually accmpany the taking f sugar syrup frm a feeder placed abve the cluster, a cnditin which may be accmpanied with egg-laying and pssible brd-rearing. Hwever in the fall, "brd-rearing s initiated may be stpped with equal suddenness (See plate 14 )«. A clny kept in a cnstant temperature case at 70 cntinued brd-rearing fr tw mnths after ther clnieb had ceased and was suppressed nly after the ease temperature was allwed t fall. The clny had been prvided with a large reserve f pllen. ur present evidence indicates that the clny will rear brd whenever the activity f the cluster will prvide brd temperatures as lng as bth pllen and hney are available in the hive. The

43 36 majrity f clnies begin brd-rearing smetime in February r early March befre spring pllen is available. Brd- rearing tends t end in this lcality by the first week f ctber* Seasnal Brd-Rearing Brd-rearing is essential t a nrmal clny when its envirnment causes the bees t be cntinually active- t is a functin necessary t the elny and since the lives f individual bees are shrtened as their activity increases, yung bees must be reared t replace thse wrn ut* The brdless perid will be discussed in the third sectin f this treatise under "Wintering, 1 * a perid requiring the cnservatin f Bee Energy in rder t prlng the life f the individual. t is necessary fr the ver-wintering bees t resumebrd-rearing when the cnditins becme favrable in the spring. The amunt f brd reared by the clny during the active seasn will determine the rate f its develpment, its prducing strength at the time f a hney flw, and the pprtunity fr increasing the number f clnies thrugh either natural swarming r cntrlled divisins. H lan (45) cnsiders that there are three phases t the annual brd-rearing cycle, a perid f initial expansin, a majr perid, and a final cntractin perid. Be states that in the case f the initial expansin perid when nce entered, it *is

44 37 cntinued in spite f cnditins which if ccurring later in the seasn wuld tend t check brd-rearing." This viewpint des nt seem t harmnize with the usual methdical reapnse which bees make t the influence f their envirnment. This tendency pinted ut by Hlan may be explained thrugh the lack f a sharp definitin f factrs which have a bearing n brd- rearing. The evidence t be presented under daily variatins in egglaying indicates that where cnditins permit, the queen has the capacity fr reaching frm a perid f nnprductin, a level exceeding 1400 eggs per day within ne week (See als plate 11 - brd nest fr August 7). The initial expansin perid may therefre be limited t a very few days when cnditins bth inside and utside the clny are favrable. The final cntractin perid may be equally abrupt when cnditins n lnger favr brd-rearing as indicated in platea 1 and 2. t shuld be pssible t explain the seasnal variatins by measuring the influence f factrs determining rates f brd-rearing. Variatin in the Queen»s Daily Rate f Egg-Laying The questin frequently arises when cnsidering prblems f brd-rearing whether the queen fluctuates in her egg prductin r whether there is a gradual increase r decrease between tw levels as shwn by 12 r 21 day measurements. Table 2 shws

45 38 the daily fluctuatin in egg-laying f three queens. Since cunts varied ccasinally frm 15 minutes t 3 hurs frm the 24 hur perids, the prductins are given as mean hurly rates. The queen in Clny & emerged June 4 and prbably mated n June 9 r 10. Her first egg prductin cvering a 19 hur perid averaged 21.3 per hur and within a week she had attained a rate equivalent t the maximum daily rate f brd-rearing fr a gd clny. t wuld seem frm a study f the three queens that sharp changes in daily egg prductin are nt likely t ccur thugh shrt cycles are evident.