DOI: 10.2478/v10289-012-0022-x Vol. 56 No. 2 2012 Journal of Apicultural Science 37

A TEST OF COCOON AND OTHER COMMON METHODS FOR NEST INITIATION IN B. lapidarius AND B. hortorum

Alena Buč ánková1,2, Vladimír Ptáč ek1

1Agricultural Research, Ltd. Troubsko, Czech Republic 2Research Institute for Fodder Crops, Ltd. Troubsko, Czech Republic e-mail: [email protected] Received 11 April 2012; accepted 21 November 2012

Summary Several methods for stimulating nest initiation (particularly the use of the Bombus terrestris cocoon) in queen of the species B. lapidarius and B. hortorum were compared. For B. lapidarius, it was determined that the percentage success rate for establishing the fi rst egg cell on a cocoon of B. terrestris is similar to that on a conspecifi c cocoon. Nest establishment, however, was signifi cantly slower on the cocoon of B. terrestris. Moreover, it was determined that queens of B. lapidarius are able to initiate a nest without hibernation. Queens hibernated in the laboratory displayed a similar percentage success rate in establishing an egg cell during stimulation with the cocoon of B. terrestris as did the outdoor queens, but the lab queens established it signifi cantly more slowly. Queens of B. hortorum did not incubate the cocoon of B. terrestris, nor did they establish an egg cell on it. Keywords: , cocoon, colony initiation, Bombus terrestris, Bombus lapidarius, Bombus hortorum.

INTRODUCTION (1985) and Ptáček (2000); the method Bumblebees are important pollinators of an added worker, later mentioned by of many agricultural crops. During the Alford (1975); and the use of interspecies past century, great advances have been cooperation to initiate nesting of the queen made in research concerning bumblebee and rearing of a brood (Ono et al., 1994). domestication. Today, several species are Bumblebees’ willingness to accept already being reared in commercial hives a brood or an individual of another species (Velthuis and Doorn, 2006). is very advantageous. This permits the The first important attempts at rearing breeding of those bumblebee species not yet bumblebees were made by Sladen(1912). domesticated and for which a conspecific He published his experience in the now brood or worker is usually not available. legendary book, “The Humble-bee”. The For interspecies cooperation, callow basis for certain stimulatory methods used workers or male cocoons of the species today for stimulating queens’ oviposition Bombus (Bombus) terrestris L. are most in the laboratory, can be traced to his frequently used due to their easy breeding experiments. These methods include, and availability. To date, the stimulatory for example, the stimulatory effect effect of the B. terrestris cocoon has of providing a brood, which today is most been detected in the species B. hypocrita frequently used in the form of a male hypocrita P., B. (Bombus) ignitus S., B. h. cocoon (Duchateau, 1994; Kwon et sapporoensis C. (Yoneda, 2008), Bombus al., 2003); the method of two queens, (Bombus) lucorum L. (Bučánková and later more developed by Plowright and Ptáček, 2010) and Bombus (Bombus) Jay (1966), Alford (1975), Duchateau cryptarum F. (Bučánková et al., 2011). Yet, not all bumblebee species seem 38 to accept the cocoon of B. terrestris. replaced daily. The containers were placed In 1998, Přidal and Hofbauer in a dark room at a temperature of 27°C published a study in which the cocoon with 60-80% humidity. of B. terrestris was not accepted by the Stimulation and breeding of queens of B. (Megabombus) pascuorum B. lapidarius queens S. or B. (Pyrobombus) hypnorum. It was Queens from nature also stated by Yoneda (2008) that queens A total of 80 queens captured outdoors of other subgenera (B. (Pyrobombus) were tested. Twenty queens were offered ardens S., B. (Diversobombus) diversu a B. lapidarius (BL) cocoon, 43 queens S. and B. (Thoracobombus) schrenkii M.) were offered a B. terrestris (BT) cocoon, were much less stimulated by the cocoon 10 queens were placed in a free pair, of B. terrestris. Unfortunately, more 2 queens were kept alone, and 5 queens details about the influence of phylogenetic had three callow honeybee workers added. relatedness on cooperation are not known. Cocoons were replaced as needed with In the first half of the 1980s, Ptáček fresh cocoons. The queens were inspected reported another stimulatory method every day. The establishment and location for the species B. terrestris which uses (on the cocoon/not on the cocoon) callow honeybee workers. In other species of the first egg cell, emerging of the first (B. (Pyrobombus) lapidarius, B. lucorum, worker, death and behaviour (incubation, B. hypnorum, B. (Pyrobombus) pratorum L., aggression, antennae contact, lack B. pascuorum, B. (Megabombus) hortorum of interest) and eventually the emergence and B. (Megabombus) ruderatus F.) this of the first young queen were checked. method did not work well (Ptáček, 1983, After the first workers emerged, 1985). the colony was transferred into For our study, we decided to test a 26.5×20×20 cm wooden hive lined with the possibilities of using the cocoon a newspaper, then kept at a temperature of B. terrestris and certain other stimulatory of 23-25°C with 40-50% humidity. For methods, in laboratory breeding of the easier manipulation, the top of the hive was species B. lapidarius L. and B. hortorum covered with plastic film. An opening was L. These species were selected because cut in the centre of the plastic film. The top they have longer tongues than B. terrestris of the hive with plastic film was covered (Hanski, 1982). B. lapidarius L. and with a wooden lid. The queen colonies B. hortorum L. are therefore suitable for that had been captured outdoors, were fed pollinating plants with a long flower tube mostly with fresh pollen. which the B. terrestris cannot pollinate. Young queens emerged in the hive, Breeding proficiency would therefore, be attempted to leave it after several days. a welcome advantage. These queens were seen on the hive walls beneath the plastic film, trying to leave. MATERIALS AND METHODS They were collected and transferred Experiments were performed during into a glass box together with unrelated the 2008-2011 time period. Queens were males. The glass box was covered with captured in the spring when they had netting and placed out in the daylight. not yet established nests at several sites The individuals had both pollen and sugar in Moravia (the Czech Republic). On the solution available. After mating they were same day as their capture or one day after, either removed from the glass box and they were placed into plastic containers placed together into a breeding container that were 14×19×7 cm. The bottom in the dark at room temperature with sugar of the container was covered with a piece solution or marked and placed back into of cardboard. They were provided with the vivarium to mate again. The queens a 60% sugar solution (90% sucrose and were then hibernated in a refrigerator at 10% fructose) and fresh pollen which was a temperature of 4-7°C. Vol. 56 No. 2 2012 Journal of Apicultural Science 39

Artificially hibernated queens homogeneity of variances, Welch’s t-test After 3-4 months, 16 hibernated queens was used. If the data did not conform to the were activated. Thirteen queens were conditions of parametric testing, even after given a B. terrestris cocoon, 2 queens had being logarithmically transformed, they a B. lucorum cocoon, and 1 queen was kept were evaluated using the Kruskal-Wallis alone. one-way analysis of variance or the Mann- Queens without hibernation Whitney U test. After being removed from the vivarium, 31 B. lapidarius queens were not RESULTS hibernated, but were placed into a breeding Comparison of stimulation methods space. of these, 6 queens were stimulated and breeding success rate for with a cocoon of B. lapidarius, 22 with B. lapidarius a cocoon of B. terrestris, and 3 queens Queens from the outdoors were kept alone. In the case of the BL cocoon variant, Non-hibernated and hibernated queens 60% of the queens established an egg cell were kept using the same methods as were on the cocoon, and 85% of the queens the queens from outdoors, but, since they established an egg cell - this includes egg were generally bred out of season, they cells on as well as not on the cocoon. In the were provided mostly with dried or frozen group of queens with a BT cocoon, 60% pollen. of the queens also initiated on the cocoon, Stimulation and breeding of the while 88% of the queens established B. hortorum queens an egg cell. No queen of the ten free pairs The capture and breeding of B. hortorum established an egg cell. of the two queens were similar to those for the aforementioned kept alone, neither initiated a nest. of the B. lapidarius. five queens kept with honeybees, three A total of 46 queens were tested. of these, initiated a nest. The significant difference 21 were offered a cocoon of B. terrestris, among these groups (p<0.001) was due to 6 queens were placed in separate pairs the unsuccessfulness of the pair-method, (queens were separated by a double mesh as the difference in the success rate which allowed odour contact but prevented of establishing an egg cell between the physical attack), 12 queens were kept queens stimulated by various cocoons is alone, and 7 queens had three callow insignificant (χ2=0.14; df=1; p=0.708). honeybee workers added. Queens with BL cocoons had The colonies of B. hortorum were reared significantly shorter intervals in during the season, so they were provided comparison to queens with BT cocoons. with fresh pollen in a tiny bowl. Since they This means shorter intervals both in the were from the group of so-called pocket number of days necessary for establishing makers, who have difficulty in collecting an egg cell (p=0.001) and in the number pollen from a bowl, their broods also were of days between egg cell establishment sprinkled with fresh pollen every day. and emerging of the first worker (p<0.001). Data was processed using the Statistica Details are presented in Table 1. 10 program, and statistical tests were Artificially hibernated queens performed for those groups for which Of the hibernated queens which had 2 n≥6. Pearson’s chi-square test(χ test) was a BT cocoon available, 54% established used to analyse the queens’ success rates an egg cell on the cocoon. In total, 77% in reaching individual nest development of the queens with a BT cocoon established stages. The influence of breeding methods an egg cell. of the two queens having a BL on the number of days necessary for cocoon available, one of them established reaching the individual stages was analysed an egg cell on the cocoon (Tab. 2). by ANOVA or t-test using logarithmically transformed data. In the case of non- 40

Table 1. Number of B. lapidarius queens captured outdoors which established an egg cell, established an egg cell on a cocoon, and produced workers and queens (including the average number of these queens ± SD)

Queens from Cocoon Cocoon Two Single Honey Result of nature/the BL BT queens queen bees the statistical outdoors (n = 20) (n = 43) (n = 10) (n = 2) (n = 5) test χ2 17/20 38/43 3/5 = 35.489; Egg cell (85 %) (88 %) 0/10 0/2 (60 %) df = 2; p < 0.001 χ2 = 0.001; Egg cell on 12/20 26/43 ---df = 1; the cocoon (60 %) (60 %) p = 0.972 χ2 17/17 31/38 3/3 = 3.588; Workers (100 %) (82 %) --(100 %) df = 1; p = 0.058 Young 4/17 11/31 queens (24 %) (35 %) --0/3- No. of young queens 17 ± 18 11 ± 9 - - - - Welch t = 3.411; A-EC 5 ± 2 12 ± 9 - - 11 ± 7 df = 52.9 ; p = 0.001 U = 102; EC-W 22 ± 8 34 ± 14 - - 39 ± 30 p < 0.001 W-YQ 67 ± 8 52 ± 18 - - - - A-EC - the average number of days ± SD the queens needed from activation to egg cell establishment; EC-W - the average number of days ± SD from egg cell establishment to emergence of the fi rst worker; W-YQ - days from emergence of the fi rst worker to emergence of the fi rst queen. Data included into statistical evaluation (n ≥ 6) and the corresponding results of the given statistical test, if signifi cant, are highlighted in bold.

Queens without hibernation Comparison of queens from the outdoors, In the group of queens with a BL cocoon without hibernation and with hibernation, available, 100% established an egg cell, stimulated by cocoon of B. terrestris and 67% of the queens established it on The queens differed significantly in the cocoon. In the group with a BT cocoon, the success rate for establishing the 41% of the queens established an egg first egg cell (χ2=9.997; df=2; p=0.007). cell and 23% of the queens established it Those queens without hibernation were on the cocoon. Each of the three queens significantly less successful than were of the group left alone, established a nest. queens from outdoors (χ2=8.636; df=1; The difference between the queens with p=0.003), while the hibernated queens BL cocoons and BT cocoons is significant did not significantly differ from the other both in terms of total initiation success groups. Also, a significant difference in rate (p=0.01) and in terms of success rate the speed of first egg cell establishment of initiation on the cocoon (p=0.041). was observed (F=10.972; df=2; p<0.001). However, no significant difference was Subsequent comparison by Scheffé’s determined in the time interval between method showed that queens from outdoors activation and establishment of the first initiate significantly faster than do queens egg cell (p=0.185) (Tab. 3). without hibernation (p=0.007) and with hibernation (p=0.001). Differences in other variables were not significant (Tab. 1, 2, 3). Vol. 56 No. 2 2012 Journal of Apicultural Science 41

Table 2. Number of B. lapidarius queens artificially hibernated which established an egg cell, established an egg cell on a cocoon, and produced workers and queens (including the average number of these queens ± SD)

Cocoon of Single Afrtificially hibernated Cocoon BT B. lucorum queen queens (n = 13) (n = 2) (n = 1) Egg cell 10/13 (77 %) 1/2 (50 %) 0/1 Egg cell on the cocoon 7/13 (54 %) 1/2 (50 %) - Workers 7/10 (70 %) 0/1 - Young queens 2/7 (29 %) - - No. of young queens 5 ± 0 A-EC 29 ± 12 42 - EC-W 26 ± 12 - - W-YQ 46 ± 0 - - A-EC - the average number of days ± SD the queens needed from activation to egg cell establishment; EC-W - the average number of days ± SD from egg cell establishment to emergence of the fi rst worker; W-YQ - days from emergence of the fi rst worker to emergence of the fi rst queen.

Table 3. Number of B. lapidarius queens without hibernation which established an egg cell, established an egg cell on a cocoon, and produced workers and queens (including the average number of these queens ± SD) Queens without Cocoon BL Cocoon BT Single queen Result of the hibernation (n = 6) (n = 22) (n = 3) statistical test χ2 = 6.618; Egg cell 6/6 (100 %) 9/22 (41 %) 3/3 (100 %) df = 1; p = 0.01 χ2 = 4.173; Egg cell on 4/6 (66 %) 5/22 (23 %) - df = 1; the cocoon p = 0.041 χ2 = 0.417; Workers 3/6 (50 %) 3/9 (33 %) 1/3 (33 %) df = 1; p = 0.519 Young queens 2/3 (66 %) 1/3 (33 %) 1/1 (100 %) - No. of young queens 7 ± 2 23 60 - t = 1.399; A-EC 18 ± 15 (n = 6) 28 ± 19 (n = 9) 4 ± 1 (n = 3) df = 13; p = 0.185 EC-W 39 ± 13 (n = 3) 31 ± 16 (n = 3) 26 (n = 1) - W-YQ 42 ± 5 (n = 2) 45 (n = 1) 38 (n = 1) -

A-EC - the average number of days ± SD the queens needed from activation to egg cell establishment; EC-W - the average number of days ± SD from egg cell establishment to emergence of the fi rst worker; W-YQ - days from emergence of the fi rst worker to emergence of the fi rst queen. Data included into statistical evaluation (n ≥ 6) and the corresponding results of the given statistical test, if signifi cant, are highlighted in bold. 42

Table 4. Number of B. lapidarius queens without regard to stimulation method used, which established an egg cell, established an egg cell on a cocoon, and produced workers and queens (including the average number of these queens ± SD)

Queens Artificially Queens from nature/ hibernated without Result of the - the outdoors queens hibernation statistical test (n = 82) (n = 16) (n = 31) χ2 62/82 12/16 18/31 = 3.506; Egg cell (76 %) (75 %) (58 %) df = 2; p = 0.173 χ2 = 4.439; Workers 54/62 7/12 7/18 df = 2; (87 %) (58 % ) (39 %) p = 0.109 χ2 Young 17/54 2/7 4/7 = 1.919; queens (31 %) (29 %) (57 %) df = 2; p = 0.383 No. of young queens 15 ± 12 5 ± 0 24 ± 25 - H = 21.645; A-EC 10 ± 8 27 ± 11 20 ± 18 df = 2; p < 0.001 H = 1.283; EC-W 31 ± 15 26 ± 12 34 ± 13 df = 2; p = 0.527 W-YQ 56 ± 17 97 ± 0 42 ± 4 - A-EC - the average number of days ± SD the queens needed from activation to egg cell establishment; EC-W - the average number of days ± SD from egg cell establishment to emergence of the fi rst worker; W-YQ - days from emergence of the fi rst worker to emergence of the fi rst queen. Data included into statistical evaluation (n ≥ 6) and the corresponding results of the given statistical test, if signifi cant, are highlighted in bold Comparison of queens from the outdoors, Comparison of stimulation methods without hibernation and with hibernation, and breeding success rate for B. hortorum regardless of the stimulation method In the group of queens with BT cocoons, When comparing queens without regard 57% of queens established an egg cell to the stimulation method used, those on the cardboard, but no queen established from outdoors, those without hibernation, it on the cocoon, and its incubation was not and those hibernated were about equally recorded. In the group of separated pairs, successful in establishing egg cells 66% of the queens established an egg cell. (p=0.173), but they differed in the speed In the group of queens with honeybees of establishing the first egg cell (p<0.001). added, 71% of the queens established Subsequent multivariate comparison an egg cell. of the queens kept alone, 100% showed that queens from outdoors of the queens established an egg cell. require a significantly lower number No significant difference in the number of days to establish an egg cell than do of days necessary for establishing the hibernated queens (p<0.001) and than first egg cell or of the emerging of the do queens without hibernation (p=0.05). first worker was observed between the No significant difference was determined individual stimulation variants. Queens between the hibernated and non-hibernated with a BT cocoon unexpectedly had queens (U=82.5; p=0.167). No statistically a better success rate in emerging of young significant differences were discovered queens in comparison to queens without among the remaining variables (Tab. 4). special stimulation (p=0.025) (Tab. 5). The overall success rate of the B. hortorum queens regardless of the stimulation method, is described in Table 6. Vol. 56 No. 2 2012 Journal of Apicultural Science 43

Table 5. Number of B. hortorum queens captured outdoors which established an egg cell, established an egg cell on a cocoon, and produced workers and queens (including the average number of these queens ± SD) Separated Cocoon BT pair of queens Single queen Honey bees Result of the (n = 21) (n = 6) (n = 9) (n = 7) statistical test χ2 = 6.55; Egg cell 12/21 4/6 9/9 6/7 df = 3; p = 0.088 Egg cell on the cocoon 0/21---- χ2 = 1.067; Workers 9/12 3/4 6/11 4/6 df = 2; p = 0.586 χ2 Young 5/9 1/3 0/6 2/4 = 5; queens df = 1; p = 0.025 No. of young queens 10 ± 8 7 - 9 ± 10 - F = 0.171; A-EC 14 ± 13 10 ± 6 12 ± 9 9 ± 5 df = 2; p = 0.844 t = 0.59; EC-W 32 ± 8 43 ± 19 30 ± 5 40 ± 30 df = 11; p = 0.567 W-YQ 38 ± 21 36 - 10 -

A-EC - the average number of days ± SD the queens needed from activation to egg cell establishment; EC-W - the average number of days ± SD from egg cell establishment to emergence of the fi rst worker; W-YQ - days from emergence of the fi rst worker to emergence of the fi rst queen. Data included into statistical evaluation (n ≥ 6) and the corresponding results of the given statistical test, if signifi cant, are highlighted in bold.

Table 6. Number of B. hortorum queens which established an egg cell, and produced workers and queens (including the average number of these queens ± SD)

(n = 51) Egg cell 37 (73 %) Workers 23 (62 %) Young queens 10 (27 %) No. of young queens 10 ± 7 A-EC 13 ± 10 EC-W 32 ± 13 W-YQ 33 ± 20 A-EC - the average number of days ± SD the queens needed from activation to egg cell establishment; EC-W - the average number of days ± SD from egg cell establishment to emergence of the fi rst worker; W-YQ - days from emergence of the fi rst worker to emergence of the fi rst queen 44

DISCUSSION understandable. The outdoor queens had Although the queens without hibernation already been active for some time before are significantly less successful when their capture. Although we have no proof stimulated by a male BT cocoon than are of this, we find it very probable that the queens from outdoors, it is evident that number of days between awakening from the B. lapidarius queens accept the BT hibernation and the establishment of an egg cocoon as a place for establishing the first cell is approximately the same. egg cell. In the case of queens from the An unwanted increase in the number outdoors, they even accept a BT cocoon of days necessary for initiating a nest, as often as they do cocoons of their own which apparently also affects the number species. It is interesting, that the lower of workers, is caused by BT cocoons. success rate of queens without hibernation The use of BT cocoons in continuous occurred only with the BT cocoon method. breeding, though, is easier and more When comparing queens regardless advantageous than using BL cocoons. of the stimulation method, this difference Cocoons of BL occur in close proximity vanishes. to other cocoons of the same batch and it The significant differences in the speeds is practically impossible to separate them of egg cell establishment are a new finding. without damage. The only possibility for While on the conspecific cocoon, the individualizing the cocoons comes at the outdoor queens establish an egg cell after price of either destroying neighbouring an average of five days. It takes the outdoor ones or using the entire batch, which can queens more than double that, on a BT have a devastating effect on the donor nest. cocoon (Tab. 1). Also, the time necessary We also tested the use of callow honeybee for the queen to raise the first worker workers. Ptáček (1985) had not observed is significantly increased. The number any cooperation between B. lapidarius of days between the first egg cell and and honeybees. For this reason, we used emerging of the first queens remains the only five queens in the experiment which same. For this reason, it is highly probable was to confirm the ineffectiveness of this that this delay is negatively reflected in stimulatory method. To our surprise, the number of workers, instead of which three queens displayed signs of accepting young queens are raised. Unfortunately, the bees (non-aggressiveness, antennae we usually had the hibernated queens and contact) and the bees occurred on the brood queens without hibernation available out of the queen similarly to B. terrestris. of season. We did not have BL cocoons In order to confirm the cooperation with available out of season. This meant that the honeybee, the experiment needs to be we could not demonstrably prove whether repeated in higher numbers. queens would achieve better results on We also consider it interesting, that one conspecific cocoons. The analysis of the of the two queens established an egg cell non-hibernated queens with a BL cocoon on the cocoon of B. lucorum. Again in (n=5) and of the queens with a BT cocoon this case, unfortunately, the experiment (n=9) which established an egg cell, did not was not performed in a sufficient number prove there to be a difference in the number of repetitions. Nevertheless, information of days between activation and the first egg on using cocoons of species other than cell. B. terrestris is not very common, so we Even though outdoor queens initiate decided to include this case. Placing the more slowly on BT cocoons (12 days), queens in free pairs did not prove very they nevertheless are significantly faster effective for outdoor queens. than hibernating queens or queens without Another observation is the ability for hibernation (27 and 28 days, respectively) the queens of B. lapidarius to initiate on the same cocoon. a generally faster a nest without hibernation and without anaesthetization by CO . The possibility initiation by the outdoor queens is 2 Vol. 56 No. 2 2012 Journal of Apicultural Science 45 of activating queens without hibernation success rate must be attributed mainly to the is advantageous from the viewpoint fact that queens captured in nature/from the of laboratory breeding. Death of queens outdoors are apparently so physiologically is frequent during hibernation, and the prepared for laying that they do not need economic costs of hibernation also are much stimulation. We also observed not negligible. We have discovered that frequent spontaneous laying in other a large proportion of already fertilized queens of the Megabombus subgenus. The queens do not display pre-hibernation problem was with the hibernated queens. behaviour common in B. terrestris (filled According to our experience dealing with abdomen, settling at one spot). Therefore, the breeding and hibernation of several we did not hibernate these queens but species, we found that only a small number instead transferred them into the breeding of hibernated queens are able to produce space. The already fertilized queens were a brood without external stimuli. At the then stimulated by BT or BL cocoons turn of 2011/2012, we activated queens in the breeding space. The cause for the of B. hortorum acquired from the stated absence of pre-hibernation behaviour hives. Due to the small number of queens is not known, but we have repeatedly (10), we tested various combinations observed that if queens are kept with the of stimulatory methods: separated pair, males after fertilization, they mate several subsequently open pair, adding a male times. The highest number of matings we cocoon or a worker of B. terrestris. Initiation recorded was 3. Fliszkiewicz (2002) was not observed, however, even after one determined that queens of B. terrestris month. When we continued the stimulation, captured outdoors in spring, had larger we recorded behavioural changes in three numbers of sperm in the spermathecae than queens. At first, some of them sometimes did queens mating in the laboratory. As in incubated the maternal BT cocoon. After nature, the queens of this species usually two months, two queens accepted the mate only once (Schmidt-Hempel brood and the workers of B. terrestris, and Schmidt-Hempel, 2000), it is and actively participated in caring for the therefore possible that repeated mating was brood. Unfortunately, they did not raise a response to insufficient mating. their own offspring and only the workers While there is no problem with the species of B. terrestris were laying. These queens B. lapidarius accepting BT cocoons, the had only frozen and dried pollen at their opposite is true for B. hortorum. of the disposal. It is possible that unsuccessful 21 queens which were offered the male BT breeding was not caused by the stimulatory cocoon, in only one case was occasional methods but by inappropriate pollen. incubation of the cocoon recorded. None As these problems do not occur in of the queens established an egg cell on the B. lapidarius, this species is more suitable cocoon. In one case, the queen repeatedly for laboratory breeding in order to pollinate bit through the BT cocoon and threw out the plants with a longer floral tube. Once the pupa. Aggressive behaviour also occurred best method for preparing the queens toward honeybees. In most instances, for hibernation is resolved, the breeding honeybees repeatedly died by the second of B. lapidarius will then be considered day. In two cases, one bee was still alive accomplished. during the establishment of an egg cell. The bee was not communicating with the CONCLUSION queen though, and showed no interest in the B. terrestris cocoons are accepted by brood. It appeared there was an apparent the queens of B. lapidarius as a place for lack of success of these stimulatory establishing the first egg cell as often as methods, yet the success rate of the egg are cocoons of their own species. They cell establishment was relatively high in all establish egg cells on B. terrestris cocoons variants (57-92%, Tab. 5). However, this significantly more slowly, and it takes them 46 significantly longer to raise the first worker. Bučánková A., Komzáková O., This slowdown may have a negative impact Cholastová T., Ptáček V. (2011) - on the total number of workers. The speed Notes on distribution of Bombus cryptarum of initiation on cocoons of B. terrestris (, Apoidea) in Moravian territory is also affected by other conditions. The (Czech Republic) and its laboratory rearing. queens overwintering in the laboratory Acta univ. agric. et silvic. Mendel. Brun., 6: or activated without hibernation need 69-73. significantly longer to establish an egg cell Duchateau M. J. (1985) - Analysis of some on the cocoons of B. terrestris than do the methods for rearing bumblebee colonies. queens from outdoors. Nevertheless, the Apidologie, 16: 225-227. stimulus of the cocoon of B. terrestris on Duchateau M. J., Toshiba H., the queens’ oviposition can be considered Velthuis H. H. W. (1994) - Diploid males a great aid to breeding techniques. It seems in the bumblebee Bombus terrestris. Entomol. that callow worker honeybees can also Exp. Appl., 71: 623-269. be used for the stimulation of queens. Another finding was the ability of the Fliszkiewicz M. (2002) - Causes of the lack queens of B. lapidarius to lay eggs without of diapause in bumble bee females (Bombus hibernation and without anaesthetization Latr., Apoidea). J. Apic. Sci., 46: 31-40. Hanski I. (1982) - Structure in bumblebee by CO2. When the problems of mating, and the best method of preparing queens communities. Ann. Zool. Fennici., 19: 319-326. for hibernation are resolved, then breeding Kwon Y. J., Saeed S., Duchateau M. J., of B. lapidarius can be considered as (2003) - Stimulation of colony initiation and having been accomplished. In contrast to colony development in Bombus terrestris by B. lapidaries, the B. terrestris cocoons were adding a male pupa: the influence of age and never accepted by B. hortorum queens. orientation. Apidologie, 34: 429-437. The callow bees were repeatedly killed Ono M., Mitsuhata M., Sasaki M., (1994) and displayed no signs of cooperation. - Use of Introduced Bombus terestris Worker Nevertheless, queens captured outdoors Helpers for Rapid Development of Japanese were initiating in large numbers. This Native B. hypocrita Colonies (Hymenoptera, spontaneous initiation apparently does ). Appl. Entomol. Zool., 29: 413-419. not occur in the following generations in a laboratory and continuous breeding is still Plowright R. C., Jay S. C. (1966) - Rearing problematic. bumblebee colonies in captivity. J. Apic. Res., 5: 155-165. ACKNOWLEDGEMENTS Ptáček V. (1983) - Indukce plodování samiček We express our thanks to Jan Votava čmeláků (Hymenoptera, Bombidae) pomocí for his assistance in the preparation in this kontaktu se včelami medonosnými (Apis article. This study was financed by research mellifera L.). (Stimulation of egg laying in project No. TA01020969 funded by the bumblebee queens by means of their contact Technology Agency of the Czech Republic. with honey bees). (Pilot study), SB. věd. prac. VŠÚP Troubsko 8, 157-161. (Cz. En. Sum.) REFERENCES Ptáček V. (1985) - Zkoušky tří metod chovu čmeláků (Hymenoptera, Bombidae). (Testing Alford D. V. (1975) - Bumblebees, Davis- three methods of rearing bumblebees.) - Poynter, London. SB. věd. prací, OSEVA, VŠÚP Troubsko, 9, Bučánková A., Ptáček V. (2010) - 56-57. (Cz. En. Sum.) Experiences in rearing of Bombus lucorum L. (Hymenoptera: Apoidea) in captivity. Úroda, 12, Vědecká příloha, 621-624. Vol. 56 No. 2 2012 Journal of Apicultural Science 47

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PRÓBA WYKORZYSTANIA KOKONÓW Bombus terrestris ORAZ INNYCH METOD INICJACJI ZAKŁADANIA GNIAZD PRZEZ MATKI B. lapidarius I B. hortorum

Buč ánková A., Ptáč ek V.

Streszczenie Porównano kilka metod stymulacji zakładania gniazd (ze szczególnym uwzględnieniem wykorzystania kokonów Bombus terrestris) przez matki B. lapidarius i B. hortorum. Stwierdzono, że procent matek B. lapidarius, które wybudowały pierwszą miseczkę na jaja na kokonie B. terrestris był zbliżony do procenta matek, które wybudowały pierwszą miseczkę na kokonach własnego gatunku. Jednak budowanie gniazda na kokonach B. terrestris przebiegało znacznie wolniej. Stwierdzono również, że matki B. lapidarius, które nie hibernowały były zdolne do zakładania gniazda. Zbadano także jaki procent matek zbudował pierwszą miseczkę na kokonie B. terrestris w zależności od warunków hibernacji. Matki hibernujące w warunkach laboratoryjnych osiągnęły podobne wyniki do matek hibernujących w warunkach naturalnych. Zbudowanie pierwszej miseczki zajęło im jednak znacznie więcej czasu. Matki B. hortorum nie inkubowały kokonów B. terrestris. Nie budowały na nich również miseczek na jaja. Słowa kluczowe: trzmiel, kokon, inicjacja rodziny, Bombus terrestris, Bombus lapidarius, Bombus hortorum. 48