Overview
The Northwestern Salamander (Ambystoma gracile) is a large, sturdy mole salamander native to the dripping, moss-draped coastal temperate rainforests of the Pacific Northwest. Inhabiting the Pacific fog belt from Alaska to northern California, it is celebrated for its prominent parotoid poison glands, sticky defensive secretions, and facultative paedomorphosis in high alpine lakes.
Biology and Physical Characteristics
Adult Northwestern Salamanders measure up to 22 cm in total length, featuring a stout body with smooth, dark chocolate-brown, olive, or charcoal skin. A defining anatomical hallmark is the pair of large, bulging parotoid glands located immediately behind the eyes, as well as a glandular ridge running along the top of the tail. When provoked, these glands exude a thick, white, sticky toxic secretion that tastes foul and causes numbness in mammalian predators.
Behavior and Ecology
Living primarily in moist subterranean burrows, under decomposing logs, and inside root tunnels, adults emerge during rainy autumn and winter nights to forage for banana slugs, earthworms, and beetles. In spring, terrestrial adults migrate to permanent ponds and lakes to mate, laying large, fist-sized gelatinous egg masses that become colonized by green algae. In cold subalpine lakes, larvae frequently become paedomorphic, retaining external gills and breeding without ever leaving the water.
Conservation and Human Impact
The Northwestern Salamander is listed as Least Concern by the IUCN, with widespread and stable populations throughout protected old-growth and second-growth forests in Olympic National Park, Mount Rainier, and British Columbia provincial parks. Introduction of non-native predatory trout to historically fishless alpine lakes represents the primary threat to larval survival.
Interesting Factoid
When attacked by a garter snake, the Northwestern Salamander butts its head and lashes its tail, smearing the predator’s face with a sticky white glue-like poison that temporarily glues the snake’s jaws shut.