Cane toad

Irikura, D., et at. (2007). Characterization of a major secretory protein in the cane toad (Bufo marinus) choroid plexus as an amphibian lipocalin-type prostaglandin D synthase. J. Biochem. 141, 173-80. 

Hypothesis 1 Chemical signaling between individuals is important to cane toad behavior. 

HPLC, LC-MS, LC-NMR and GC-MS will be used to examine the skin secretions of the cane toad. Making no presupposition about the composition of the secretion, we will develop analytical methods to elucidate volatiles and nonvolatiles, organic and water-soluble, stable and non-stable, and major and minor components. 

Chemicals that cycle in abundance are obvious candidates for consideration as pheromones. Armed with effective analytical techniques we can address the issue of cane toad chemical plasticity with respect to different variables (Table 39.1). We will also investigate the impact of crude and fractionated secretions on the behavior of cane toads, and compare these responses between the same groupings of animals, i.e. sex, life-stage, season etc. We have identified three stages in the cane toad life cycle that are likely controlled by chemical signals, and are an ideal place to start attempting to disrupt their chemical ecology. 

Hypothesis 2 Cane toads produce a chemosignal that controls / facilitates reproduc-tion, either through increasing aggregation or attraction. 

Table 39.1 Variables which may contribute to cane toad (B. marinus) chemical plasticity... 

Hypothesis 3 Females avoid laying eggs into a water body already containing cane toad eggs / tadpoles, they detect this through a chemical cue in the water. 

Hypothesis 4 An alarm signal exists which reduces time to metamorphosis and mass at metamorphosis of cane toad tadpoles. 

Cane toad biogenic amines fall into three classes, the catecholamines, the indolylalkylamines and an alkaloid. The catecholamine adrenaline is a significant portion (6-11%) of the skin secretions (Erspamer 1994 Gregerman 1952). Parotoid and... 

Chemistry of Skin Secretions of the Cane Toad (Bufo marinus)... 

Grigg, G. C., Taylor, A., McCallum, H. and Fletcher, L. (2006) Monitoring the impact of cane toads (Bufo marinus) on Northern Territory frogs - a progress report. In K. L. Molloy and W. R. Henderson (Eds.), Science of Cane Toad Invasion and Control, Proceedings of the Invasive Animals CRC/CSIRO/QLD NRM W Cane Toad Workshop, June 2006, Brisbane. Invasive Animals Cooperative Research Centre, Canberra, pp. 47-54 Hearnden, M. N. (1991) The reproductive and larval ecology of Bufo marinus (Anura Bufonidae). 

Addo Elephant National Park (AENP), elephant population at, compared to free-ranging population at Ndarakwai Ranch, Tanzania, 82-88 Adrenaline, from cane toad skin secretion, 412 Adult odour preferences in rodents, role of early olfactory learning in development of, 251-258... 

Bufotenine can also be exuded from the skin of the cane toad (hence the prefix bufo-). This is a red or green toad which was mistakenly purported to be the object of "toad licking" in order to become intoxicated. The reports of such activity were highly exaggerated. Licking the skin of the cane toad has made the lickers extremely ill. In fact in South America indigenous tribes used the material as an arrow poison. 

The ideal solution would be a natural beetle predator. Well, one did exist. Word had come from Hawaii that a species of toad, bufo marinus had already earned the name cane toad for its ability to protect sugar cane by dining on grayback beetles. So, in 1935, Australia imported 102 cane toads from Hawaii to drive the pesky beetles out of town. The Australians made a special pond filled with beautiful water lilies to encourage the toads romantic behavior. The little creatures needed no encouragement, however, and soon the pond was alive with cane-toad tadpoles. When the toads matured, the cane growers deposited them in the cane fields, fully expecting the beetles to succumb to the toads voracious appetite. 

But how, exactly, does a toad secretion effect the human mind Bufotenin has a very close chemical similarity to serotonin, a substance used by the nervous system to transmit information from one nerve cell to another. Bufotenin overwhelms serotonin-sensitive cells and triggers effects ranging from hallucinations to seizures. Two Toronto men learned about this the hard way. They ended up in hospital after licking a cane toad they had purchased in a pet shop specializing in exotic animals. And a five-year-old Arizona boy did have a brush with death after he put a Colorado River toad into his mouth. (Just why he did this can only be explained by other five-year-old boys.) In any case, this species, bufo alvarias, is the most toxic toad in North America. The youngster developed seizures that had to be controlled with medication. 

What will eventually happen to the cane toads Some birds have learned to turn the toads over on their backs and eat their tongues. Entrepreneurs plan to manufacture toadskin wallets. 

One final thought on the matter of cane toads could the presence of a mind-altering substance in their skin have given rise to all those children s stories about the girl who kisses a toad and turns him into a prince Perhaps. Who knows what you re going to see after you kiss one of those hallucinogenic warty-skinned amphibians. 

Ju, Y.K., Allen, D.G. (2005). Cyanide inhibits the NaVCa exchanger in isolated cardiac pacemaker cells of the cane toad. Pflugers Arch. 449 442-8. 

Also In amphibians like the cane toad, Bufo marinus, considerable amounts of morphine can be detected In the skin. 

Apparently due to non-spectacular results, solanaceous tropane alkaloids of other structural types are not well-described with regard to biological/pharmaco-logical properties. Aliphatic esters such as valeroidine, poroidine, isoporoidine, and valtropine had a depressant effect on the diphasic electric response of the Sartorius muscle of Bufo marinus L cane toad (Bufonidae), characterized by a gradual fall of the action potential to a final abolition together with a 50-100% increase in the conduction time (Traumer and McCallum 1950). In contrast, atropine, hyoscine, and tigloidine had a delayed recovery effect. 

CRO 11] Crossland M.R., Shine R., Cues for cannibalism cane toad tadpoles use chemical signals to locate and consume conspecific eggs , Oikos, vol. 120, pp. 327-332,2011. 

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