Overview
The Columbia Spotted Frog (Rana luteiventris) is a tough, cold-adapted true frog native to the crystal-clear alpine lakes and rushing mountain streams of the northern Rocky Mountains and Pacific Northwest. Renowned for its gorgeous salmon-pink to reddish-orange belly wash and its remarkable ability to thrive at elevations exceeding 9,000 feet, it spends winter hibernating under thick mountain ice in freezing, oxygenated lake shallows.
Biology and Physical Characteristics
Rana luteiventris has a medium-to-large, streamlined body with moist, bumpy skin colored olive-green to tan-brown, patterned with irregular black spots featuring light centers across its back. Its underside is gleaming white on the chest, blending into an intense salmon-red, peach, or orange wash on the lower belly and hind legs. Its eyes are positioned high and turned slightly upward, and its fully webbed hind feet make it a powerful swimmer.
Behavior and Ecology
Highly aquatic, the Columbia Spotted Frog rarely wanders far from permanent water, basking along the grassy margins of beaver ponds and subalpine tarns. During the brief alpine summer, males call from underwater, uttering rapid, low-pitched clicking sounds that resemble a distant helicopter or tongue clicks. In autumn, adults dive into deep, spring-fed pools that do not freeze solid, absorbing dissolved oxygen through their skin all winter.
Conservation and Human Impact
Classified as Least Concern by the IUCN, the species maintains healthy populations in wilderness areas of Glacier, Yellowstone, and Grand Teton national parks. However, isolated Great Basin desert spring populations face pressures from groundwater pumping, and alpine populations are vulnerable to introduced predatory trout that consume eggs and tadpoles.
Interesting Factoid
Columbia Spotted Frogs are winter ice survivors: they spend up to six months of the year hibernating on the mud bottoms of subalpine lakes completely trapped beneath thick sheets of solid mountain ice.