Cascades frog | |
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Mount Pilchuck State Park | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Amphibia |
Order: | Anura |
Family: | Ranidae |
Genus: | Rana |
Species: | R. cascadae |
Binomial name | |
Rana cascadae Slater, 1939 | |
The Cascades frog (Rana cascadae) is a species of frog in the family Ranidae found in the Pacific Northwest, mainly in the Cascade Range and Olympic Mountains.
The Cascades frog has a green to brown color on its back and a light yellow on its throat and belly. A range from a few to about 50 gray spots are located on its back. Depending on the situation, the spots may change color from the lighter gray/brown to a darker black spot. The colors on the frog's back are also used to attract mates. The shape of the frog's head is most commonly an oval with the mouth coming out to a slight specific point. Adult frogs range from 50 to 65 mm in length.
The advertisement call of the R. cascadae is a faint series of low, grating, clucking noises. Calls are produced at night and during the day from above and under the water. [2]
The Cascade frog was first discovered in the Cascade Mountains in the California regions. It can be found throughout the Cascade Mountains from Washington through Oregon, and California. They concentrate heavily around the volcanic area of the peaks. Its natural habitats are temperate forests, temperate grassland, rivers, swamps, freshwater lakes, intermittent freshwater lakes, freshwater marshes generally between 665 and 2,450 m (2,182 and 8,038 ft) in elevation. The range may extend lower in Washington. They can be found in relatively small, permanent and temporary ponds also found along streams in summer. The adults generally stay close to water, particularly along sunny shores, under dry summer conditions, but can be found traversing uplands during high humidity.
Cascades frogs lay their eggs May 20 through July 10, depending on when the snow melts and creates ponds in which the eggs are laid. First, egg masses are deposited in comparatively warm water along gradually sloping shorelines, often over soft substrates protected from severe wave action. Females can only breed once a year, but whether they skip years remains unknown. A single female will lay up to 425 eggs at a time, but very few tadpoles will live past their first year. The placement of clusters of egg masses in shallow water soon after the first thaw can make them susceptible to freezing and pathogen transmission between clusters. The eggs hatch within eight to 20 days. Their larval period lasts 80 to 95 days. Most frogs reach their full size after three years, after which they become fertile and can begin mating. Adults appear to use the same breeding sites for several years.
Larvae are thought to be primarily benthic feeders, but specific preferences are not well known. The diets of the adult Cascades frogs are poorly known, as well, but they are thought to consume a variety of invertebrate prey and will occasionally consume other frogs and tadpoles.
Females have a higher mortality rate than the males, but both are believed to live over five years, sometime reaching up to seven.
Recently, a decline in the Cascade frog species has occurred, but the declines are not too serious, and usually only occur in the southern part of this frog's range. Causes are not fully known, but introduced predators such as trout and bullfrogs, UV-B radiation, diseases, and loss of open meadow habitat due to fire suppression have been suggested. Fertilizers such as urea may also pose a threat to the Cascades frogs, because the juveniles were not capable of sensing and avoiding toxic levels in laboratory studies.
The main predators of the Cascades frogs are the raccoon, mink, coyote, water bugs (Belostomatidae), garter snakes (Thamnophis sirtalis), and several bird species, such as the sharp shinned hawks, owls, Canada jays, and American robin. The long-toed salamander and adult R. cascadae frogs are predators to the eggs and tadpoles, as well.
To guard itself from other microorganisms that live in the environment, the Cascades frog produces high concentrations of antimicrobial peptides it secretes from its skin in response to infection or stress. According to Conlon, "frogs belonging to the genus Rana represent a particularly rich source of peptides with diverse structures and specificities against micro-organisms". He began testing the frog secretions to determine whether or not the peptides would have an effect on bacteria that attack human cells. He found the chemical ranatuerin-2CSa, which is produced by R. cascadae, impeded the growth of E. coli and S. aureus in humans. These anti-infective agents give the Cascades frogs “therapeutic potential for the future”, according to Conlon.
A drawback of the R. cascadae peptide, however, is it acts as a blood thinner for humans and decreases the supply of oxygen in the bloodstream. A recently discovered chemical, D-lysine, was produced by adding amino acids to the peptides to help decrease the toxicity to the human cells. It is a substitute for ranatuerin-2CSa, which makes analogs of naturally occurring peptides that lack significant hemolytic activity. Since the strength of the blood thinning properties is greatly reduced, it is almost harmless to humans.
True frogs is the common name for the frog family Ranidae. They have the widest distribution of any frog family. They are abundant throughout most of the world, occurring on all continents except Antarctica. The true frogs are present in North America, northern South America, Europe, Africa, and Asia. The Asian range extends across the East Indies to New Guinea and a single species, the Australian wood frog, has spread into the far north of Australia.
Lithobates pipiens formerly Rana pipiens, commonly known as the northern leopard frog, is a species of leopard frog from the true frog family, native to parts of Canada and the United States. It is the state amphibian of Minnesota and Vermont.
Lithobates sylvaticus or Rana sylvatica, commonly known as the wood frog, is a frog species that has a broad distribution over North America, extending from the boreal forest of the north to the southern Appalachians, with several notable disjunct populations including lowland eastern North Carolina. The wood frog has garnered attention from biologists because of its freeze tolerance, relatively great degree of terrestrialism, interesting habitat associations, and relatively long-range movements.
Rana is a genus of frogs commonly known as the Holarctic true frogs, pond frogs or brown frogs. Members of this genus are found through much of Eurasia and western North America. Many other genera were formerly included here. These true frogs are usually largish species characterized by their slim waists and wrinkled skin; many have thin ridges running along their backs, but they generally lack "warts" as in typical toads. They are excellent jumpers due to their long, slender legs. The typical webbing found on their hind feet allows for easy movement through water. Coloration is mostly greens and browns above, with darker and yellowish spots.
The pickerel frog is a small North American frog, characterized by the appearance of seemingly "hand-drawn" squares on its dorsal surface. Pickerel frogs are the only poisonous frog native to the United States.
The foothill yellow-legged frog is a small-sized frog from the genus Rana in the family Ranidae. This species was historically found in the Coast Ranges from northern Oregon, through California, and into Baja California, Mexico as well as in the foothills of the Sierra Nevada and southern Cascade Range in California. The foothill yellow-legged frog is a Federal Species of Concern and California State Endangered. A federal rule to list four out of six extant distinct population segments (DPS) under the Endangered Species Act was proposed in December 2021.
The Columbia spotted frog is a North American species of frog. It is green to brown in color with spots on the dorsal surface. The belly and upper lip are white in color. Individuals can be distinguished from other Rana species by their shorter back legs, narrow snout, and upturned eyes. Since they spend most of their time in the water, they also have more webbing in their hind feet than similar species. Although not threatened, this animal has been studied as a model species for the effects of habitat fragmentation.
Lithobates sphenocephalus or Rana sphenocephala, commonly known as the southern leopard frog, is a medium-sized anuran in the family Ranidae. It is native to eastern North America from Kansas to New York to Florida. It is also an introduced species in some areas. This species lives in cool, clear water in the north, whereas in the south it occurs in warmer turbid and murky waters of coastal and floodplain swamps, twilight zones of caves, and abandoned mines.
The pig frog is a species of aquatic frog found in the Southeastern United States, from South Carolina to Texas. Some sources also refer to it as the lagoon frog or the southern bullfrog.
The northern red-legged frog is a species of amphibian whose range is the coastal region stretching from southwest British Columbia to southern Mendocino County in Northern California, and is protected in Oregon and California. As a member of the genus Rana, this species is considered a true frog, with characteristic smooth skin and a narrow waist. This frog requires still waters for breeding, and is rarely found at any great distance from its breeding ponds or marshes.
Lithobates is a genus of true frogs, of the family Ranidae. The name is derived from litho- (stone) and the Greek bates, meaning one that treads on rock, or rock climber.
The Oregon spotted frog is a member of the frog family Ranidae of order Anura. It is a medium-sized aquatic frog endemic to the Pacific Northwest and historically well distributed in the Puget Trough/Willamette Valley province and the Cascade Mountains of south-central Washington and Oregon. It is relatively rare within its range and is listed globally as vulnerable.
Phyllomedusa trinitatis, known as the leaf-nesting frog, Trinidadian leaf frog, or Trinidadian monkey frog, is a species of frog in the subfamily Phyllomedusinae. It is found in Venezuela and the island of Trinidad. It is threatened by habitat loss.
Leptodactylus labyrinthicus is a species of frog in the family Leptodactylidae. Its common names are labyrinth frog, pepper frog, South American pepper frog, and pepper foam frog. This frog is found in central and southeastern Brazil, northeast Argentina, and eastern Paraguay. Earlier reports from Bolivia refer to Leptodactylus vastus, or possibly an unnamed species.
The river frog is a species of aquatic frog in the family Ranidae. It is endemic to the southeastern United States. Its natural habitats are temperate rivers, swamps, freshwater lakes and freshwater marshes. It is threatened by habitat loss.
The Mississippi gopher frog, also known commonly as the dark gopher frog, the dusky gopher frog, and the St. Tammany gopher frog, is a critically endangered species of frog in the family Ranidae. The species is endemic to the southern United States. Its natural habitats are temperate coastal forests and intermittent freshwater marshes. This secretive frog is on average 3 in (8 cm) long, with a dark brown or black dorsal surface covered in warts. It is a federally listed endangered species of the United States.
The showy leopard frog is a species of frog in the family Ranidae endemic to Mexico.
Vaillant's frog is a species of frog in the family Ranidae found in Central America. Its natural habitats are subtropical or tropical dry forests, subtropical or tropical moist lowland forests, subtropical or tropical swamps, rivers, swamps, freshwater lakes, intermittent freshwater lakes, freshwater marshes, intermittent freshwater marshes, rural gardens, heavily degraded former forests, water storage areas, ponds, and canals and ditches.
The lowland leopard frog is a species of frog in the family Ranidae that is found in Mexico and the United States.
Lithobates clamitans or Rana clamitans, commonly known as the green frog, is a species of frog native to eastern North America. The two subspecies are the bronze frog and the northern green frog.