The role of resources and risks in regulating wild bee populations

Annual Review of Entomology

Volumn 56, Issue , 2011, Pages 293-312

  Roulston, T'Ai H ^a   Goodell, Karen ^b  

^a UNIVERSITY OF VIRGINIA   (United States)

^b OHIO STATE UNIVERSITY   (United States)

Author keywords

Apiformes; bees; direct effects; pollinators; resource limitation

Indexed keywords

AGRICULTURE; ANIMAL; ARTICLE; BEE; ECOSYSTEM; ENVIRONMENTAL PROTECTION; POLLINATION;

AGRICULTURE; ANIMALS; BEES; CONSERVATION OF NATURAL RESOURCES; ECOSYSTEM; POLLINATION;

APOIDEA;

EID: 78650900311     PISSN: 00664170     EISSN: None     Source Type: Book Series    
DOI: 10.1146/annurev-ento-120709-144802     Document Type: Article

References (140)

1. Abbott VA, Nadeau JL, Higo HA, Winston ML. 2008. Lethal and sublethal effects of imidacloprid on Osmia lignaria and clothianidin on Megachile rotundata (Hymenoptera: Megachilidae). J. Econ. Entomol. 101:784-96
2. Aizen MA, Garibaldi LA, Cunningham SA, Klein AM. 2008. Long-term global trends in crop yield and production reveal no current pollination shortage but increasing pollinator dependency. Curr. Biol. 18:1572-75
3. Allen-Wardell G, Bernhardt P, Bitner R, Búrquez A, Buchmann S, et al. 1998. The potential consequences of pollinator declines on the conservation of biodiversity and stability of food crop yields. Conserv. Biol. 12:8-17
4. Alston DG, Tepedino VJ, Bradley BA, Toler TR, Griswold TL, Messinger SM. 2007. Effects of the insecticide phosmet on solitary bee foraging and nesting in orchards of Capitol Reef National Park, Utah. Environ. Entomol. 36:811-16
5. Bernadou A, Demares F, Couret-Fauvel T, Sandoz JC, Gauthier M. 2009. Effect of fipronil on side-specific antennal tactile learning in the honeybee. J. Insect Physiol. 55:1099-106
6. Biesmeijer JC, Roberts SPM, Reemer M, Ohlemuller R, Edwards M, et al. 2006. Parallel declines in pollinators and insect-pollinated plants in Britain and the Netherlands. Science 313:351-54
7. Bosch J, Kemp WP. 2002. Developing and establishing bee species as crop pollinators: the example of Osmia spp. (Hymenoptera: Megachilidae) and fruit trees. Bull. Entomol. Res. 92:3-16
8. Bowers JE, Dimmitt MA. 1994. Flowering phenology of six woody plants in the northern sonoran desert. Bull. Torrey Bot. Club 121:215-29
9. Brosi BJ. 2009. The effects of forest fragmentation on euglossine bee communities (Hymenoptera: Apidae: Euglossini). Biol. Conserv. 142:414-23
10. Brown MJF, Loosli R, Schmid-Hempel P. 2000. Condition-dependent expression of virulence in a trypanosome infecting bumblebees. Oikos 91:421-27
11. Brown MJF, Schmid-Hempel R, Schmid-Hempel P. 2003. Strong context-dependent virulence in a host-parasite system: reconciling genetic evidence with theory. J. Anim. Ecol. 72:994-1002
12. Campbell JW, Hanula JL, Waldrop TA. 2007. Effects of prescribed fire and fire surrogates on floral visiting insects of the blue ridge province in North Carolina. Biol. Conserv. 134:393-404
13. Cane JH. 2001. Habitat fragmentation and native bees: a premature verdict? Conserv. Ecol. 5(1):3
14. Cane JH. 2005. Bees, pollination and the challenges of sprawl. In Nature in Fragments: The Legacy of Sprawl, ed. EA Johnson, MW Klemens, pp. 109-24. New York: Columbia Univ. Press
15. Cane JH, Minckley RL, Kervin LJ, Roulston TH, Williams NM. 2006. Complex responses within a desert bee guild (Hymenoptera: Apiformes) to urban habitat fragmentation. Ecol. Appl. 16:632-44
16. Cane JH, Sipes SD. 2006. Floral specialization by bees: analytical methods and a revised lexicon for oligolecty. In Plant-Pollinator Interactions: From Specialization to Generalization, ed. NM Waser, J Ollerton, pp. 99-122. Chicago: Univ. Chicago Press
17. Carre G, Roche P, Chifflet R, Morison N, Bommarco R, et al. 2009. Landscape context and habitat type as drivers of bee diversity in European annual crops. Agric. Ecosyst. Environ. 133:40-47
18. Carvell C. 2002. Habitat use and conservation of bumblebees (Bombus spp.) under different grassland management regimes. Biol. Conserv. 103:33-49
19. Carvell C, Meek WR, Pywell RF, Nowakowski M. 2004. The response of foraging bumblebees to successional change in newly created arable field margins. Biol. Conserv. 118:327-39
20. Carvell C, Rothery P, Pywell RF, Heard MS. 2008. Effects of resource availability and social parasite invasion on field colonies of Bombus terrestris. Ecol. Entomol. 33:321-27
21. Cole FR, Pritchard AE. 1964. The genus Mallophora and related asilid genera in North America. Univ. Calif. Publ. Entomol. 36:43-100
22. Colla SR, Packer L. 2008. Evidence for decline in eastern North American bumblebees (Hymenoptera: Apidae), with special focus on Bombus affinis Cresson. Biodivers. Conserv. 17:1379-91
23. Danforth BN. 1999. Emergence dynamics and bet hedging in a desert bee, Perdita portalis. Proc. R. Soc. Lond. B Biol. Sci. 266:1985-94
24. Dukas R. 2005. Bumble bee predators reduce pollinator density and plant fitness. Ecology 86:1401-6
25. Dukas R, Morse DH. 2003. Crab spiders affect flower visitation by bees. Oikos 101:157-63
26. Durrer S, Schmid-Hempel P. 1995. Parasites and the regional distribution of bumble bees. Ecography 18:114-22
27. Ebeling A, Klein AM, Schumacher J, Weisser WW, Tscharntke T. 2008. How does plant richness affect pollinator richness and temporal stability of flower visits? Oikos 117:1808-15
28. Elliott SE. 2009. Subalpine bumble bee foraging distances and densities in relation to floral availability. Environ. Entomol. 38:748-56
29. Elliott SE. 2009. Surplus nectar available for subalpine bumble bee colony growth. Environ. Entomol. 38:1680-89
30. Eltz T, Bruhl CA, Imiyabir Z, Linsenmair KE. 2003. Nesting and nest trees of stingless bees (Apidae: Meliponini) in lowland dipterocarp forests in Sabah, Malaysia, with implications for forest management. Forest Ecol. Manage. 172:301-13
31. Floyd T. 1996. Top-down impacts on creosotebush herbivores in a spatially and temporally complex environment. Ecology 77:1544-55
32. Fontaine C, Dajoz I, Meriguet J, Loreau M. 2006. Functional diversity of plant-pollinator interaction webs enhances the persistence of plant communities. PLoS Biol. 4:129-35
33. Franzen M, Nilsson SG. 2010. Both population size and patch quality affect local extinctions and colonizations. Proc. R. Soc. Lond. B Biol. Sci. 277:79-85
34. Galeotti P, Inglisa M. 2001. Estimating predation impact on honeybees Apis mellifera L. by European bee-eaters Merops apiaster L. Rev. D Ecol. La Terre Et La Vie 56:373-88
35. Gels JA, Held DW, Potter DA. 2002. Hazards of insecticides to the bumble bees Bombus impatiens (Hymenoptera: Apidae) foraging on flowering white clover in turf. J. Econ. Entomol. 95:722-28
36. Giles V, Ascher JS. 2006. A survey of the bees of the Black Rock Forest preserve, New York (Hymenoptera: Apoidea). J. Hymenopt. Res. 15:208-31
37. Gomez JM, Bosch J, Perfectti F, Fernandez J, Abdelaziz M. 2007. Pollinator diversity affects plant reproduction and recruitment: the tradeoffs of generalization. Oecologia 153:597-605
38. Goodell K. 2003. Food availability affects Osmia pumila (Hymenoptera: Megachilidae) foraging, reproduction, and brood parasitism. Oecologia 134:518-27
39. Goodell K. 2008. Invasive exotic plant-bee interactions. In Bee Pollination in Agroecosystems, ed. RR James, TL Pitts-Singer, pp. 166-83. London: Oxford Univ. Press
40. Goulson D, Hughes WOH, Derwent LC, Stout JC. 2002. Colony growth of the bumblebee, Bombus terrestris, in improved and conventional agricultural and suburban habitats. Oecologia 130:267-73
41. Greenleaf SS, Kremen C. 2006. Wild bees enhance honey bees' pollination of hybrid sunflower. Proc. Natl. Acad. Sci. USA 103:13890-95
42. Greenleaf SS, Williams NM, Winfree R, Kremen C. 2007. Bee foraging ranges and their relationship to body size. Oecologia 153:589-96
43. Hegland SJ, Boeke L. 2006. Relationships between the density and diversity of floral resources and flower visitor activity in a temperate grassland community. Ecol. Entomol. 31:532-38
44. Heinrich B. 1976. Flowering phenologies: bog, woodland, and disturbed habitats. Ecology 57:890-99
45. Herrera CM, Garcia IM, Perez R. 2008. Invisible floral larcenies: microbial communities degrade floral nectar of bumble bee-pollinated plants. Ecology 89:2369-76
46. Hines HM, Hendrix SD. 2005. Bumble bee (Hymenoptera: Apidae) diversity and abundance in tallgrass prairie patches: effects of local and landscape floral resources. Environ. Entomol. 34:1477-84
47. Hoehn P, Tscharntke T, Tylianakis JM, Steffan-Dewenter I. 2008. Functional group diversity of bee pollinators increases crop yield. Proc. R. Soc. B Biol. Sci. 275:2283-91
48. Horne M. 1995. Leaf area and toughness: effects on nesting material preferences of Megachile rotundata (Hymenoptera: Megachilidae). Ann. Entomol. Soc. Am. 88:868-75
49. Imhoof B, Schmid-Hempel P. 1999. Colony success of the bumble bee, Bombus terrestris in relation to infections by two protozoan parasites, Crithidia bombi and Nosema bombi. Insectes Soc. 46:233-38
50. James RR. 2008. The problem of disease when domesticating bees. In Bee Pollination in Agricultural Ecosystems, ed. RR James, TL Pitts-Singer, pp. 124-41. Oxford, UK: Oxford Univ. Press
51. Johansen CA. 1977. Pesticides and pollinators. Annu. Rev. Entomol. 22:177-92
52. Julier HE, Roulston TH. 2009. Wild bee abundance and pollination service in cultivated pumpkins: farm management, nesting behavior and landscape effects. J. Econ. Entomol. 102:563-73
53. Kearns CA, Oliveras DM. 2009. Environmental factors affecting bee diversity in urban and remote grassland plots in Boulder, Colorado. J. Insect Conserv. 13:655-65
54. Kevan P. 1975. Forest application of the insecticide fenitrothion and its effects on wild bee populations (Hymenoptera: Apoidea) of lowbush blueberries (Vaccinium) in southern New Brunswick, Canada. Biol. Conserv. 7:301-9
55. Kevan PG, LaBerge WE. 1979. Demise and recovery of native pollinator populations through pesticide use and some economic implications. In Proc. IVth Int. Symp. Pollination, Md. Agric. Exp. Sta. Spec. Misc. Publ. 1:489-508
56. Kevan PG, Mohr NA, Offer MD, Kemp JR. 1988. The squash and gourd bee, Peponapis pruinosa (Hymenoptera: Anthophoridae), in Ontario, Canada. Proc. Entomol. Soc. Ont. 119:9-15
57. Kim J, Williams N, Kremen C. 2006. Effects of cultivation and proximity to natural habitat on ground-nesting native bees in California sunflower fields. J. Kans. Entomol. Soc. 79:309-20
58. Kladivko EJ. 2001. Tillage systems and soil ecology. Soil Tillage Res. 61:61-76
59. Kleijn D, van Langevelde F. 2006. Interacting effects of landscape context and habitat quality on flower visiting insects in agricultural landscapes. Basic Appl. Ecol. 7:201-14
60. Klein AM, Vaissiere BE, Cane JH, Steffan-Dewenter I, Cunningham SA, et al. 2007. Importance of pollinators in changing landscapes for world crops. Proc. R. Soc. Lond. B Biol. Sci. 274:303-13
61. Kremen C, Williams NM, Aizen MA, Gemmill-Herren B, LeBuhn G, et al. 2007. Pollination and other ecosystem services produced by mobile organisms: a conceptual framework for the effects of land-use change. Ecol. Lett. 10:299-314
62. Kremen C, Williams NM, Thorp RW. 2002. Crop pollination from native bees at risk from agricultural intensification. Proc. Natl. Acad. Sci. USA 99:16812-16
63. Krombein KV. 1967. Trap-Nesting Wasps and Bees: Life Histories, Nests and Associates. Washington, DC: Smithsonian Press. 570 pp.
64. Kruess A, Tscharntke T. 2002. Grazing intensity and the diversity of grasshoppers, butterflies, and trap-nesting bees and wasps. Conserv. Biol. 16:1570-80
65. Larsson M, Franzen M. 2007. Critical resource levels of pollen for the declining bee Andrena hattorfiana (Hymenoptera, Andrenidae). Biol. Conserv. 134:405-14
66. Lonsdorf E, Kremen C, Ricketts T, Winfree R, Williams N, Greenleaf S. 2009. Modelling pollination services across agricultural landscapes. Ann. Bot. 103:1589-600
67. Mathewson JA. 1968. Nest construction and life history of the eastern cucurbit bee, Peponapis pruinosa (Hymenoptera: Apoidea). J. Kans. Entomol. Soc. 41:255-61
68. McFrederick QS, LeBuhn G. 2006. Are urban parks refuges for bumble bees Bombus spp. (Hymenoptera: Apidae)? Biol. Conserv. 129:372-82
69. Michener CD. 2000. The Bees of the World. Baltimore: Johns Hopkins Univ. Press. 913 pp.
70. Minckley RL, Cane JH, Kervin LJ. 2000. Origins and ecological consequences of pollen specialization among desert bees. Proc. R. Soc. Lond. B Biol. Sci. 267:265-71
71. Minckley RL, Roulston TH. 2006. Incidental mutualisms and pollen specialization among bees. In Plant-Pollinator Interactions: From Specialization to Generalization, ed. NM Waser, J Ollerton, pp. 69-98. Chicago: Univ. Chicago Press
72. Minckley RL, Wcislo WT, Yanega D, Buchmann SL. 1994. Behavior and phenology of a specialist bee (Dieunomia) and sunflower (Helianthus) pollen availability. Ecology 75:1406-19
73. Mommaerts V, Reynders S, Boulet J, Besard L, Sterk G, Smagghe G. 2010. Risk assessment for side-effects of neonicotinoids against bumblebees with and without impairing foraging behavior. Ecotoxicology 19:207-15
74. Moretti M, de Bello F, Roberts SPM, Potts SG. 2009. Taxonomical versus functional responses of bee communities to fire in two contrasting climatic regions. J. Anim. Ecol. 78:98-108
75. Moretti M, Obrist MK, Duelli P. 2004. Arthropod biodiversity after forest fires: winners and losers in the winter fire regime of the southern Alps. Ecography 27:173-86
76. Muller A, Diener S, Schnyder S, Stutz K, Sedivy C, Dorn S. 2006. Quantitative pollen requirements of solitary bees: implications for bee conservation and the evolution of bee-flower relationships. Biol. Conserv. 130:604-15
77. Mullin CA, Frazier M, Frazier JL, Ashcraft S, Simonds R, et al. 2010. High levels of miticides and agrochemicals in North American apiaries: implications for honey bee health. PLoS One 5:1-19
78. Ne'eman G, Dafni A. 1999. Fire, bees, and seed production in a Mediterranean key species Salvia fruticosa Miller (Lamiaceae). Isr. J. Plant Sci. 47:157-63
79. Neff JL. 2003. Nest and provisioning biology of the bee Panurginus polytrichus Cockerell (Hymenoptera: Andrenidae), with a description of a new Holeopasites species (Hymenoptera: Apidae), its probable nest parasite. J. Kans. Entomol. Soc. 76:203-16
80. Otterstatter MC, Gegear RJ, Colla SR, Thomson JD. 2005. Effects of parasitic mites and protozoa on the flower constancy and foraging rate of bumble bees. Behav. Ecol. Sociobiol. 58:383-89
81. Otterstatter MC, Thomson JD. 2008. Does pathogen spillover from commercially reared bumble bees threaten wild pollinators? PLoS One 3:9
82. Otti O, Schmid-Hempel P. 2007. Nosema bombi: a pollinator parasite with detrimental effects. J. Invertebr. Pathol. 96:118-24
83. Otti O, Schmid-Hempel P. 2008. A field experiment on the effect of Nosema bombi in colonies of the bumblebee Bombus terrestris. Ecol. Entomol. 33:577-82
84. Pelletier L, McNeil JN. 2003. The effect of food supplementation on reproductive success in bumblebee field colonies. Oikos 103:688-94
85. Petanidou T, Ellis WN. 1993. Pollinating fauna of a phryganic ecosystem: composition and diversity. Biodivers. Lett. 1:9-22
86. Potts SG, Biesmeijer JC, Kremen C, Neumann P, Schweiger O, Kuhn WE. 2010. Global pollinator declines: trends, impacts and drivers. Trends Ecol. Evol. 25:345-53
87. Potts SG, Vulliamy B, Dafni A, Ne'eman G, O'Toole C, et al. 2003. Response of plant-pollinator communities to fire: changes in diversity, abundance and floral reward structure. Oikos 101:103-12
88. Potts SG, Vulliamy B, Dafni A, Ne'eman G, Willmer P. 2003. Linking bees and flowers: How do floral communities structure pollinator communities? Ecology 84:2628-42
89. Potts SG, Vulliamy B, Roberts S, O'Toole C, Dafni A, et al. 2005. Role of nesting resources in organising diverse bee communities in a Mediterranean landscape. Ecol. Entomol. 30:78-85
90. Price PW, Westoby M, Rice B. 1988. Parasite-mediated competition: some predictions and tests. Am. Nat. 131:544-55
91. Pyke GH. 1984. Optimal foraging theory: a critical review. Annu. Rev. Ecol. Syst. 15:523-75
92. Quintero C, Morales CL, Aizen MA. Effects of anthropogenic habitat disturbance on local pollinator diversity and species turnover across a precipitation gradient. Biodivers. Conserv. 19:257-74
93. Ricketts TH. 2004. Tropical forest fragments enhance pollinator activity in nearby coffee crops. Conserv. Biol. 18:1262-71
94. Romey WL, Ascher JS, Powell DA, Yanek M. 2007. Impacts of logging on midsummer diversity of native bees (Apoidea) in a northern hardwood forest. J. Kans. Entomol. Soc. 80:327-38
95. Rosenheim JA. 1996. An evolutionary argument for egg limitation. Evolution 50:2089-94
96. Roubik DW. 1989. Ecology and Natural History of Tropical Bees. Cambridge: Cambridge Univ. Press. 514 pp.
97. Roubik DW, Villanueva-Gutiérrez R. 2009. Invasive Africanized honey bee impact on native solitary bees: a pollen resource and trap nest analysis. Biol. J. Linn. Soc. 98:152-60
98. Rundlof M, Nilsson H, Smith HG. 2008. Interacting effects of farming practice and landscape context on bumblebees. Biol. Conserv. 141:417-26
99. Schmid-Hempel P. 1998. Parasites in Social Insects. Princeton, NJ: Princeton Univ. Press. 409 pp.
100. Schmid-Hempel P, Durrer S. 1991. Parasites, floral resources and reproduction in natural populations of bumblebees. Oikos 62:342-50
101. Scott-Dupree CD, Conroy L, Harris CR. 2009. Impact of currently used or potentially useful insecticides for canola agroecosystems on Bombus impatiens (Hymenoptera: Apidae), Megachile rotundata (Hy-menoptera: Megachilidae), and Osmia lignaria (Hymenoptera: Megachilidae). J. Econ. Entomol. 102:177-82
102. Shearin AF, Reberg-Horton SC, Gallandt ER. 2007. Direct effects of tillage on the activity density of ground beetle (Coleoptera: Carabidae) weed seed predators. Environ. Entomol. 36:1140-46
103. Sheffield CS, Kevan PG, Westby SM, Smith RF. 2008. Diversity of cavity-nesting bees (Hymenoptera: Apoidea) within apple orchards and wild habitats in the Annapolis Valley, Nova Scotia, Canada. Can. Entomol. 140:235-49
104. Shuler RE, Roulston TH, Farris GE. 2005. Farming practices influence wild pollinator populations on squash and pumpkins. J. Econ. Entomol. 98:790-95
105. Slagle MW, Hendrix SD. 2009. Reproduction of Amorpha canescens (Fabaceae) and diversity of its bee community in a fragmented landscape. Oecologia 161:813-23
106. Stark JD, Banks JE. 2003. Population-level effects of pesticides and other toxicants on arthropods. Annu. Rev. Entomol. 48:505-19
107. Steffan-Dewenter I. 2002. Landscape context affects trap-nesting bees, wasps, and their natural enemies. Ecol. Entomol. 27:631-37
108. Steffan-Dewenter I, Munzenberg U, Burger C, Thies C, Tscharntke T. 2002. Scale-dependent effects of landscape context on three pollinator guilds. Ecology 83:1421-32
109. Steffan-Dewenter I, Schiele S. 2004. Nest-site fidelity, body weight and population size of the red mason bee, Osmia rufa (Hymenoptera: Megachilidae), evaluated by mark-recapture experiments. Entomol. Gen. 27:123-32
110. Steffan-Dewenter I, Schiele S. 2008. Do resources or natural enemies drive bee population dynamics in fragmented habitats? Ecology 89:1375-87
111. Storer TI, Vansell GH. 1935. Bee-eating proclivities of the striped skunk. J. Mammal. 16:118-21
112. Stout JC, Morales CL. 2009. Ecological impacts of invasive alien species on bees. Apidologie 40:388-409
113. Stubblefield JW, Seger J, Wenzel JW, Heisler MM. 1993. Temporal, spatial, sex-ratio and body-size heterogeneity of prey species taken by the beewolf Philanthus sanbornii (Hymenoptera: Sphecidae). Philos. Trans. R. Soc. Lond. Ser. B 339:397-423
114. Tasei JN, Carre S, Bosio PG, Debray P, Hariot J. 1987. Effects of the pyrethroid insecticide, WL85871 and phosalone on adults and progeny of the leaf-cutting bee Megachile rotundata F., pollinator of lucerne. Pestic. Sci. 21:119-28
115. Valdovinos FS, Chiappa E, Simonetti JA. 2009. Nestedness of bee assemblages in an endemic South American forest: the role of pine matrix and small fragments. J. Insect Conserv. 13:449-52
116. Van Dreische RG, Bellows TS. 1996. Biological Control. New York: Chapman & Hall
117. van Engelsdorp D, Evans JD, Saegerman C, Mullin C, Haubruge E, et al. 2009. Colony collapse disorder: a descriptive study. PLoS One 4:17
118. van Engelsdorp D, Meixner MD. 2010. A historical review of managed honey bee populations in Europe and the United States and the factors that may affect them. J. Invertebr. Pathol. 103:S80-S95
119. Vergara CH, Badano EI. 2009. Pollinator diversity increases fruit production in Mexican coffee plantations: the importance of rustic management systems. Agric. Ecosyst. Environ. 129:117-23
120. Vergara CH, Schroder S, Almanza MT, Wittmann D. 2003. Suppression of ovarian development of Bombus terrestris workers by B. terrestris queens, Psithyrus vestalis and Psithyrus bohemicus females. Apidologie 34:563-68
121. Vicens N, Bosch J, Blas M. 1994. Biology and population structure of Osmia tricornis Latreille (Hym., Megachilidae). J. Appl. Entomol. 117:300-6
122. Visscher PK, Danforth BN. 1993. Biology of Calliopsis pugionis (Hymenoptera: Andrenidae): nesting, foraging, and investment sex ratio. Ann. Entomol. Soc. Am. 86:822-32
123. Vulliamy B, Potts SG, Willmer PG. 2006. The effects of cattle grazing on plant-pollinator communities in a fragmented Mediterranean landscape. Oikos 114:529-43
124. Wcislo WT, Cane JH. 1996. Floral resource utilization by solitary bees (Hymenoptera: Apoidea) and exploitation of their stored foods by natural enemies. Annu. Rev. Entomol. 41:195-224
125. Westphal C, Bommarco R, Carre G, Lamborn E, Morison N, et al. 2008. Measuring bee diversity in different European habitats and biogeographical regions. Ecol. Monogr. 78:653-71
126. Westphal C, Steffan-Dewenter I, Tscharntke T. 2003. Mass flowering crops enhance pollinator densities at a landscape scale. Ecol. Lett. 6:961-65
127. Westphal C, Steffan-Dewenter I, Tscharntke T. 2006. Bumblebees experience landscapes at different spatial scales: possible implications for coexistence. Oecologia 149:289-300
128. Whittington R, Winston ML. 2003. Effects of Nosema bombi and its treatment fumagillin on bumble bee (Bombus occidentalis) colonies. J. Invertebr. Pathol. 84:54-58
129. Williams N, Crone EE, Roulston TH, Minckley RL, Packer L, Potts SG. 2010. Ecological and life history traits predict bee species responses to environmental disturbances. Biol. Conserv. In press
130. Williams NM, Kremen C. 2007. Resource distributions among habitats determine solitary bee offspring production in a mosaic landscape. Ecol. Appl. 17:910-21
131. Winfree R, Aguilar R, Vazquez DP, LeBuhn G, Aizen MA. 2009. A meta-analysis of bees' responses to anthropogenic disturbance. Ecology 90:2068-76
132. Winfree R, Griswold T, Kremen C. 2007. Effect of human disturbance on bee communities in a forested ecosystem. Conserv. Biol. 21:213-23
133. Winfree R, Williams NM, Dushoff J, Kremen C. 2007. Native bees provide insurance against ongoing honey bee losses. Ecol. Lett. 10:1105-13
134. Winfree R, Williams NM, Gaines H, Ascher JS, Kremen C. 2008. Wild bee pollinators provide the majority of crop visitation across land-use gradients in New Jersey and Pennsylvania, USA. J. Appl. Ecol. 45:793-802
135. Woodcock BA, Potts SG, Tscheulin T, Pilgrim E, Ramsey AJ, et al. 2009. Responses of invertebrate trophic level, feeding guild and body size to the management of improved grassland field margins. J. Appl. Ecol. 46:920-29
136. Xie ZH, Williams PH, Tang Y. 2008. The effect of grazing on bumblebees in the high rangelands of the Eastern Tibetan Plateau of Sichuan. J. Insect Conserv. 12:695-703
137. Yanega D. 1990. Philopatry and nest founding in a primitively social bee, Halictus rubicundus. Behav. Ecol. Sociobiol. 27:37-42
138. Yang EC, Chuang YC, Chen YL, Chang LH. 2008. Abnormal foraging behavior induced by sublethal dosage of imidacloprid in the honey bee (Hymenoptera: Apidae). J. Econ. Entomol. 101:1743-48
139. Zammit J, Hogendoorn K, Schwarz MP. 2008. Strong constraints to independent nesting in a facultatively social bee: quantifying the effects of enemies-at-the-nest. Insectes Soc. 55:74-78
140. Zurbuchen A, Cheesman S, Klaiber J, Müller A, Hein S, Dorn S. 2010. Long foraging distances impose high costs on offspring production in solitary bees. J. Anim. Ecol. 79:674-81