Bufo americanus

More controversially, endocrine disruption as a consequence of exposure to the herbicide atrazine (2-chloro-4-ethylamine-6-isopropylamine-s-triazine), one of the most widely used herbicides in the world, has also been hypothesized to explain various adverse biological effects in frog populations in the United States. Exposure to atrazine in the laboratory at high concentrations, far exceeding those found in the natural environment, has been reported to induce external deformities in the anuran species Rana pipiens, Rana sylvatica, and Bufo americanus (Allran and Karasov 2001). Studies by Hayes et al. have suggested that atrazine can induce hermaphroditism in amphibians at environmentally relevant concentrations (Hayes et al. 2002 Hayes et al. 2003). Laboratory studies with atrazine also indicated the herbicide... 

American toad, Bufo americanus tadpoles held in lead-enriched waters (0, 500, 750, or 1000 pg Pb/L) for 144 h then given choice of lead-containing solutions (0, 500, 750, or 1000 pg/L) in fluvorium No deaths. Toads did not prefer or avoid lead-containing solutions 48... 

Steele, C.W., S. Strickler-Shaw, and D.H. Taylor. 1991. Failure of Bufo americanus tadpoles to avoid lead-enriched water. Jour. Herpetol. 25 241-243. 

American toad, Bufo americanus 690 Predicted no effect on survival of late-stage larvae after exposure for 30 days 26... 

Toad tadpoles Bufo americanus Negative response to non-siblings in Y-test Waldman, 1981... 

The secretions of toad tadpoles affect the behavior of predators. Largemouth bass, Micropterus salmonides, even when starved for 1 day, almost totally reject tadpoles of Bufo americanus (Fig. 10.6) and Bufo woodhousei. However, the himgrier they become, the more tadpoles they will eat. With increasing experience with these tadpoles, the bass take fewer into their mouths and spit more out. In choice experiments, they prefer tadpoles of the spring peeper, Hyla crucifer, to those of Bufo spp. (Kruse and Stone, 1984). 

Fish discriminate between palatable and toxic prey. For instance, largemouth bass, Micropterus salmonides, reject the toxic tadpoles of the toad Bufo americanus but eat those of the spring peeper, Hyla crucifer [Kruse and Stone, 1984). 

Ambystoma maculatum wood frog, Rana sylvatica American toad, Bufo americanus Zebnafish, Brachydanio rerio exposed for 6 months from embryos to adults 0.002 mg/L >9.2 mg/L... 

A new toxic alkaloid, marinobufagin 3-suberoyl-L-glutamine ester (36a), has been isolated from the skin of the poison toad (Bufo americanus). The partial synthesis of the toxin from the ester (36b) was also reported.80... 

Hall RJ and S wineford D, Uptake of methoxychlor from food and water by the American toad (Bufo americanus), Bull. Environ. Contam. Toxicol., 23, 335, 1979. 

American toad, Bufo americanus, 68, 188 Bufo arenarum, 81,541, 848, 861 Bufo spp., 68, 81, 122, 173, 178, 188, 264, 541,551,717, 848, 861,874 Giant toad, Bufo marinus, 178 Narrow-mouthed toad, Gastrophryne carolinensis, 31, 569, 879 Southern toad, Bufo terrestris, 264... 

Pancak, M. K., and Taylor, D. H., 1983, Seasonal and daily plasma corticosterone rhythms in American toads, Bufo americanus, Gen. Comp. Endocrin. 50 490-497. 

Gallie, J. A., Mumme, R. L., and Wissinger, S. A., 2001, Experience has no effect on the development of chemosensory recognition of predators by tadpoles of the American toad, Bufo americanus, Herpetologica, 57 376-383. 

Brockelman, W. Y. (1968). Natural regulation of density in tadpoles of Bufo americanus. Ph.D. Thesis, University of Michigan, Ann Arbor. 

American toad (Bufo americanus) tadpoles associate preferentially with their siblings when groups are placed in laboratory pools (Waldman and Adler, 1979 Waldman, 1981). Laboratory-reared larvae, when released in natural ponds, form schools consisting predominantly of siblings (Waldman, 1982b). 

Beiswenger, R. E., 1975, Structure and function in aggregations of tadpoles of the American toad, Bufo americanus, Herpetologica, 31 222. Blaustein, A. R., and O Hara, R. K., 1981, Genetic control for sibling recognition Nature, 290 246. 

Bufo americanus)," Ph.D. thesis. State University of New York, Albany. 

Waldman, B., 1986, Preference for unfamiliar siblings over familiar nonsiblings in American toad (Bufo americanus) tadpoles, Anim. Behav., 34 48. 

Therefore, to study the effects of pollution in natural habitats are more informative the representatives of natural populations (Stroganov, 1971). Field studies are conducted on widely distributed amphibian species Rana pipens (Allran Karasov, 2000, 2001), Rana arvalis (Andren et al, 1989), Rana temporaria (Leontieva Semenov, 1997 Dunson et al, 1992 Johansson et al, 2001), Bufo americanus (Hecnar, 1995) and other species which by 1992 had... 

Bacillus, 350 Bacillus rossius, 350 Blaberus discoidalis, 359 Bombina variegata, 106 Bombyx mori, 98, 118 Bradijsia elegans, 116 Bufo americanus, 106 Bufo bufo, 5, 106 Bufo valliceps, 106 Bufo viridis, 108 Bufo woodhousei fowleri, 106... 

Orientation via chemical cues may be more important in some species than in others. For example, Oldham (1966, 1967) studied homing and orientation in American toads Bufo americanus) and green frogs Rana clamitans). Oldham (1966) partially destroyed the olfactory tracts of 99 American toads and used 99 intact toads treated as operational controls. An additional 112 toads were left untreated. The toads were then transported to a point of land between two pools. About the same frequencies of returns occurred to the pools. Oldham concluded that olfaction was not necessary for orientation and homing in American toads. However, since only a portion of the olfactory system was destroyed, it is possible that olfaction was still involved in homing and orientation. 

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