In 2003, the Natural Heritage Advisory Council to the Oregon State Land Board identified the California slender salamanders residing in Winchuck Slope as part of Oregon's natural heritage that needed to be conserved Notes: In 2002, the Oregon Department of Fish and Wildlife adopted a rule to protect nongame wildlife by making it illegal to hunt, trap, pursue, kill, take, catch, angle for, or have in possession, either dead or alive, whole or in part, a California slender salamander. Seen in the oak habitat of Mt Diablo.The state of Oregon has taken seriously their duty to protect the California slender salamander. What makes this amphibian notable is that this species resides primarily in a limited range within California as one of a handful quasi-endemic amphibians in the state. Prey which employ behavior patterns unfamiliar to the predator will be at a selective advantage.The California slender salamander (Batrachoseps attenuatus) is a lungless salamander that is found primarily in coastal mountain areas of Northern California, United States as well as in a limited part of the western foothills of the Sierra Nevada, California, in patches of the northern Central Valley of California, and in extreme southwestern Oregon. The protean display probably insures against learned counter measures by incorporating unpredictability as a basic behavior component. The protean display delayed the predator's reaction time and thereby reduced the effectiveness of the predatory response. Predator-prey interactions of 22 potential vertebrate predators and slender salamanders indicated the following: 1) variable prey palatability but no lethal effects when prey was ingested, 2) successful attacks on salamanders were made to the head and body area, 3) unsuccessful attacks were made on the tail, 4) the protean display was observed in 10.0 percent of successful attacks and 79.2 percent of unsuccessful attacks, and 5) tail autotomy occurred in 0.01 percent of successful attacks and 63.2 percent of unsuccessful attacks. No difference was noted in the distance moved by animals with regenerating or complete tails. Exposure to the chemical extracts of these species followed by a tactile stimulus resulted in a 22.5 ± 9.3 percent increase in the mean distance moved during the protean display. elegans) and western aquatic garter snake (T. Animals with regenerating tails exhibited protean displays when exposed to chemical extracts of these species: Pacific giant salamander (Dicamptodon ensatus), arboreal salamander (Aneides lugubris), ringneck snake (Diadophis punctatus), common garter snake (Thamnophis sirtalis), western terrestrial garter snake (T. Chemical extracts of potential predators elicited protean responses only in slender salamanders with regenerating tails. The mean distance and time of movement were 11.5 cm and 1.02 s respectively. Direction of movement of the protean display from a consistent tactile stimulus contact point appeared to be random. Protean behavior is defined as that behavior which is sufficiently unsystematic to prevent a predator from predicting in detail the position or actions of the prey. Slender salamanders exhibited protean displays when presented with tactile and olfactory stimuli. During this same period, the monthly percentage of animals with absent or regenerating tails increased from 24.3 to 45.2 in the redwood forest, 26.9 to 73.9 in the edge and 28.9 to 73.9 in the grassland habitats. From March through August 61.9 percent of the animals collected in the field were found within this temperature range. With relative humidity greater than 70 percent, this species' temperature preference ranges from 100 to 15.50 C. Limited data suggest that this species becomes nocturnal during the drier summer months. Nocturnal surface activity remained relatively constant in all habitats from March through August. From March through August the monthly mean number of animals found during the diurnal sample decreased by 50.0 percent in grassland habitats.
Surface activity was positively correlated with rainfall and ground temperatures. The habitat types investigated included: 1) second growth coast redwood (Sequoia sempervirens)forest, 2) grassland and 3)the forest/grassland edge. Seasonal surface activity patterns and predator escape behavior of the California slender salamander(Batrachoseps attenuatus) were studied from March through August 1971, near Crannell, California.
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