Predation amphibian defenses

Amphibians are vulnerable to predation and show diverse predator defenses. We hypothesized that the common red-backed salamander should try to evade two common terrestrial predators, the garter snake and the spotted salamander, by avoiding locations containing their scent. When given a choice of clean substrates or those soiled by these predators, the red-backed salamander avoided the soiled substrates. To test whether they avoided the waste products and not the predator scent, we gave test subjects a choice between substrates soiled by predators and those soiled by red-backed salamanders. Salamanders pref-ered conspecific substrates to predator substrates, and in combination with other findings, our data show that red-backed salamanders probably reduce the likelihood of predation by avoiding locations with the chemical traces of predators. 

Many organisms rely on anti-predator defenses after contact with a predator (Brodie, Formanowicz Brodie, 1991). Because energetic costs and mortality risks are increased during contact, some species avoid these interactions whenever possible. A number of animals chemically detect and avoid predators, including invertebrates (Parker Shulman, 1986 Alexander Covich, 1991 Turner, 1996), fish (Keefe, 1992 Smith, 1992 Mathis Smith, 1993), reptiles (Thoen, Bauwens Verheyen, 1986 Dial, 1989 Cooper, 1990), and mammals (Weldon, 1990). In anuran amphibians, tadpoles commonly avoid the waterborne odors of predators (Petranka, Kats Sih, 1987 Flowers Graves, 1997 Kie-secker, Chi vers Blaustein, 1997), and among caudate amphibians, both larval and adult... 

The use of chemical cues in predator/prey interaction appears widespread among amphibians (Kats Dill 1998). Chemical alarm pheromones have been examined most extensively in larval frogs and toads (Chivers Smith 1998). However, recent experiments also suggest that caudate amphibians use chemical alarm pheromones. Numerous studies have investigated the use of chemical substances that make amphibians noxious or toxic to predators. Chemical cues from predators often induce antipredator responses in amphibian prey. In some cases, chemical cues may be the primary sensory stimuli used for predator recognition. Chemosen-sory-induced antipredator responses may include behavioral defenses as well as alterations in life-history characteristics. 

Responses of amphibians to chemical cues of predators could include behavioral and morphological defenses, as well as alterations in life-history characteristics. The majority of research to date has focused on behavioral responses, however, the importance of chemical cues in the other types of defenses warrants attention. 

The term biological adhesive includes the adhesive secretion used by organisms for attachment, construction, obstruction, defense, and predation (Smith and Callow 2006 Graham 2005). These natural glues are produced in marine and other wet environments by fish, holothurians, mollusks, arthropods, worms, bacteria, algae or fungi, and on land by amphibians, spiders, insects, etc. 

---