Rana luteiventris
(Columbia Spotted Frog)
Formerly: Rana pretiosa

Ralu.jpg (5319 bytes)

Key Characteristics:

Adult Characteristics

Tadpole Characteristics

Egg Characteristics

Light colored stripe
on upper lip

Eyes very inset


Narrow pointed snout

Intestines visible

Spherical clusters

Upturned eyes

green color

Eggs float

pink or yellow ventrally

      .  .  

Webbing extends
to end of toes

      .  .  

Males call

    . .   

General Description:
The Columbia Spotted Frog is a medium-sized frog reaching sizes of up to 90mm (3.5 in.) in length.  Their dorsal ground color ranges from olive green to brown and is marked by spots having irregular borders and light-colored centers.  The ventral ground color is a light cream or white but the abdomen and legs are a brightly colored salmon color   or yellow (young frogs lack this coloration).   A final characteristic dealing with color is the light-colored stripe that runs along the upper lip.  Morphological characteristics that distinguish the Columbia Spotted Frog are the narrow snout and the upturned eyes.   The eyes appear to be mostly uncovered by the eyelid when viewed from above.   They have shorter hind legs than Northern Leopard Frogs of comparable size.   The structure of their feet hints at their aquatic lifestyle since the webbing extends nearly to the tip of the longest toe.  During the breeding season, males will congregate at suitable breeding sites and call.  The call has been described as a series of 6-9 low (soft and hard to hear)  "clucks".

Columbia Spotted Frog tadpoles are generally brownish-green dorsally with gold flecks.  Ventrally these tadpoles have a silvery color and their intestines are visible.  Columbia Spotted Frogs have inset and upturned eyes.  They reach a size of around 80mm (3.1 in.) before metamorphosing.

The egg masses of Columbia Spotted Frogs are generally easy to find and recognize.  The eggs are laid in small spheres that may include up to 1300 eggs.  The egg masses absorb water and become softball-sized spherical masses that float to the surface (Charles R. Peterson pers. com.).  The individual eggs are 2.3mm or 1/10 in. in diameter and are pigmented.  The egg masses are usually laid in the shallows of a permanent water source.  They are not attached to vegetation and float freely in the water.  Several females may lay their clutch in the same area and the same site may be reused in subsequent years.

Idaho Distribution:
In Idaho, Columbia Spotted Frogs can be found in appropriate habitat throughout much of the northern part of the state.  There are also some isolated populations in southwestern Idaho.

From extreme southeastern Alaska, south through western Alberta to coastal Oregon and Washington, and east to northern Wyoming, northern Utah, and central Nevada.

Columbia Spotted Frogs are fairly aquatic and are generally found in or near permanent bodies of water such as lakes, ponds, sluggish streams and marshes.  The littoral zone is generally comprised of emergent vegetation including grasses and sedges.   During the summer these frogs can be found some distance from the breeding sites but still associated with moist vegetation.

Found from sea level to about 3000 m, usually in hilly areas near cool, permanent, quiet water in streams, rivers, lakes, pools, springs, and marshes. Highly aquatic, but may disperse into forests, grasslands, and brushlands. In the Northwest, prefers areas with thick algae and emergent vegetation, but may use sunken, dead, or decaying vegetation as escape cover.

Opportunistic. Eats wide variety of insects as well as different mollusks, crustaceans, and arachnids. Larvae eat algae, organic debris, plant tissue, and minute water-borne organisms.

Hibernates/aestivates, depending on range. Inactive in winter in north. May move overland in spring and summer after breeding. Species is thought to be declining in parts of range, but appears widespread and abundant in Idaho. Bullfrogs are predators.

Breeds: February at sea level in British Columbia; mid-March at 1395 m in Utah; and from May through June at 2377 m in Wyoming. Wyoming study found that females breed yearly at low elevations, and every 2-3 yr at high elevations. Females may lay egg masses in communal clusters. Males may require 4 yr (females 6 yr) to reach maturity.



Unprotected nongame species

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State Rank:


Important State References:
Munger, J.C., L. Heberger, D. Logan, W. Peterson, L. Mealey, and M. Caughlin. 1994. A survey of the herpetofauna of the Bruneau Resource Area, Boise District, with focus on the spotted frog (Rana pretiosa). Idaho Bur. Land Manage. Tech. Bull. 94-7.

Species description, key characteristics and original work by John Cossel Jr. © 1997
Species ecological information from Groves et al. ©1997.
Original images provided by Charles R. Peterson © 1997
Design and Optimization by Ean Harker©1999, 2000.
DAI layout by Stephen Burton, and Mike Legler © 1999.