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The endangered Sonoma County population of the California Tiger Salamander, Ambystoma californiense, undergoes migrations between breeding pools and upland dry-season refugia. Orientation in this species during breeding migrations has been addressed minimally in previous studies, and literature is particularly sparse concerning newly metamorphosed juveniles. Previous works have not addressed the ability of metamorphs to orient or the way in which they search for upland refugia. The initial migration from natal pools to uplands following metamorphosis has been identified as a crucial life-history juncture for the persistence of this species. We evaluated fine-scale movements of newly metamorphosed California Tiger Salamanders as they moved away from breeding pools by capturing salamanders with a drift fence and then tracking individuals with fluorescent powder. Here we show that newly metamorphosed juveniles do not move randomly, and that they can re-orient to their upland migration after being interrupted and disoriented. Further, we demonstrate that while searching for burrow refugia, metamorph movement can be characterized as a correlated random walk. [ABSTRACT FROM AUTHOR]

Population studies of diminutive species often present unique challenges associated with methods of identifying individuals in a manner that can be reliable and retained over long periods of time. Small snakes present even more difficulties, as many marking methods rely on the use of either invasive implantation of devices, such as passive integrated transponder (PIT) tags, or through mutilation such as branding or scale clipping. Here I present an alternative method by utilizing a flatbed scanner to obtain consistent images of sufficient quality for use in photographic identification of the Common Sharp-tailed Snake (Contia tenuis) using the unique individual pigmentation patterns on the venter of the head. Additionally, I show that HotSpotter© software consistently scored image pairs of known and assessed matches higher than between pairs of known and assessed mismatches using the flatbed scanner imagery. This method provides a repeatable, reliable, non-invasive, and non-mutilating alternative to more traditional methods of identifying individual snakes. [ABSTRACT FROM AUTHOR]

Misdirected amplexus has been reported between conspecifics, congeners, between different amphibian families, and between amphibians and non-amphibian objects. We observed misdirected amplexus between a Pacific Treefrog and a Western Toad, wherein the treefrog amplexed the toad's leg. These types of events can result in reproductive interference and have also been considered an evolutionary trap for some species. [ABSTRACT FROM AUTHOR]