448 



Non-native Species — Our Livinf> Resources 



For further information: 



Tammy Keniry 



Illinois Natural History Survey 



Lake Michigan Biological Station 



400 1 7tli sl 



Zion. IL 60099 



References 



Holland, R.E. 1993. Changes in the planktonic diatoms and 

 water transparency in Hatchery Bay, Bass Island area, 

 western Lake Erie since the establishment of the zebra 

 mussel. Journal of Great Lakes Res. 19:617-624. 



Leach. J.H. 1992. Impacts of the zebra mussel {Dreissena 

 polyinorpha) on water quality and fish spawning reefs in 

 western Lake Erie. Pages 38 1 -.395 in T.F. Nalepa and 

 D.W. Schloesser, eds. Zebra mussels: biology, impacts, 

 and control. Lewis Publishers, Boca Raton, FL. 



Mackie, G.L. 1991. Biology of the exotic zebra mussel, 

 Dreissena polymorpha. in relation to native bivalves and 

 its potential impact on Lake St. Clair. Hydrobiologia 

 219:251-268. 



Marsden, J.E. 1992. Standard protocol for monitoring and 

 sampling zebra mussels. Illinois Natural History Survey 

 Biological Notes 138. 40 pp. 



Marsden, J.E., N. Trudeau, and T. Keniry. 1993. Zebra mus- 

 sel study on Lake Michigan. Final report to the Illinois 

 Department of Conservation. Illinois Natural History 

 Survey Tech. Rep. 93/14. 51 pp. 



Nelson, S. 1992. A pound of cure for a ton of mussels. 

 Aqualicus: Journal of the Shedd Aquarium 23:28-29. 



Reeders, H.H., A. bij de Vaate, and R. Noordhuis. 1992. 

 Potential of the zebra mussel {Dreissena polymorpha) for 

 water quality management. Pages 439-45 1 in T.F. Nalepa 

 and D.W. Schloesser, eds. Zebra mussels: biology, 

 impacts, and control. Lewis Publishers, Boca Raton, FL. 



Scott, W.B., and E.J. Crossman. 1973. Freshwater fishes of 

 Canada. Bull. 184. Fisheries Research Board of Canada, 

 Ottawa, 966 pp. 



Africanized 

 Bees in North 

 America 



by 

 Michael R. Kunzinann 



National Biological Service 



Stephen L. Buchinami 

 John F. Edwards 

 Steven C. Thoenes 

 Eric H. Erickson 

 U.S. Department of 

 Agriculture 



The honeybee genus Apis likely ha.s the 

 greatest breadth of pollen diet of any insect 

 and. because of its human-caused cosmopolitan 

 distribution, the species directly affects the 

 reproductive biology of about 25% of the 

 world's flowering plants (Schmalzel 1980; 

 Buchmann et al. 1992). This situation has pro- 

 found consequences for agribusiness, native 

 plants and animals, and ecosystems. In 1956. 

 bee geneticist Warwick E. Kerr imported queen 

 bees of an African race (Apis meUifera scutella- 

 ta) into Brazil to breed a more productive hon- 

 eybee that was better adapted to the Neotropical 

 climate and vegetation (Kerr 1967). The follow- 

 ing year, 26 of Kerr's Africanized honeybee 

 queens were inadvertently released into the sur- 

 rounding forest (Winston 1987). Since then, the 

 Africanized hybrids have been expanding their 

 range northward, with an average rate of 

 between 330 and 500 km (200 and 300 mi) each 

 year (Fig, 1). 



The first U.S. Africanized honeybee colony 

 was reported in October 1990, at Hidalgo. 

 Texas, along the international boundary. By fall 

 1993, Africanized honeybees (AHBs) had 

 extended their territory north and west into 

 numerous counties of Arizona. New Mexico, 

 and Texas (Fig. 2). Since the first U,S, AHB 

 swarm was detected, the rate of spread has 

 accelerated to over 600 km (375 mi) per year in 

 the southwestern United States (Guzman- 

 Novoa and Page 1994), 



European honeybees (EHBs) were intro- 

 duced into North America as early as the 16th 

 centui7 by Spanish conquistadors and mission- 

 aries (Brand 1988), Today, one of the three most 

 common subspecies or races of the EHB. the 

 Italian honeybee (A.m. ligiistica). is nearly pan- 

 demic throughout North America because of its 

 popularity with professional and hobbyist bee- 

 keepers. As a consequence, these non-native 

 bees have become naturalized and have been a 

 part of the North American arthropod biota for 

 about 3,500 bee generations, or at least the past 



Africanized honeybees svvami outside a trap in Costa Rica. 



200 years (Buchmann et al. 1992). European 

 honeybees are commonly seen visiting agricul- 

 tural food crops, cultivated flowers, and road- 

 side wildflowers to gather nectar and pollen. 

 They are even common in areas far from human 

 population centers. These bees are also the pre- 

 ferred, "managed" pollinator for over 100 U.S. 

 agricultural crops (e,g,. fruits, vegetables, and 

 some nuts), most of which depend on or benefit 

 from insect pollination. The value of these pol- 

 lination services by EHBs is estimated at $5- 

 $10 billion annually in the United States 

 (Southwick and Southwick 1992). 



Africanized and European honeybees repre- 

 sent divergent subspecies within the meUifera 

 species of the genus Apis. Both have nearly the 

 same biochemistry, morphology, genetics, diet, 

 and reproductive and other behaviors. Their 

 diet includes pollen and spores from most seed 

 plants. Both EHBs and AHBs are social bees 

 living in perennial colonies. They are active on 

 most days collecting nectar, water, pollen, and 

 plant resins for their subsistence. These honey- 

 bees "hoard" excess honey as energy-rich car- 

 bohydrate reserves in hexagonal wax combs. 

 Energy from honey consumption partially sup- 

 ports brood-rearing and. most importantly, sup- 

 plies the energy necessary for foraging flights 

 by thousands of adult worker bees. 



