Cascades Frog
Encyclopedia
The Cascades Frog is a species of frog
in the Ranidae family.
It is found in western United States
and possibly Canada
, mainly in the Cascade Range
and Olympic Mountains
.
, and California
. They concentrate heavily around the volcanic area of the peaks. Its natural habitat
s are temperate forest
s, temperate grassland
, river
s, swamp
s, freshwater lake
s, intermittent freshwater lakes, freshwater marsh
es generally between 665 m (2,180 ft) and 2,450 m (8,040 ft) 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.
The diet of the adult Cascade frogs is poorly known as well, but they are thought to consume a variety of invertebrate prey and will occasionally consume other frogs and tadpoles.
Recently there has been a decline in the Cascade frog species. However 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 like trout and bullfrog
s, 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 Cascade frogs, because the juveniles were not capable of sensing and avoiding toxic levels in laboratory studies.
, mink coyote, water bugs (Belostomatidae), garter snake
s (Thamnophis sirtalis), and several bird species such as the sharp shinned hawks, owls
, gray jay
s, and robins
. The long toed salamander and adult cascadae frogs are predators to the eggs and tadpoles as well.
s that live in the environment, the cascade frog produces high concentrations of antimicrobial peptides that it secretes from its skin in response to infection or stress. In studies done by Conlon, it has been found that “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 in order to determine whether or not the peptides would have an effect on bacterium that attack human cells. His discovery was that 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 Cascade frogs “therapeutic potential for the future” according to Conlon.
A drawback of the R. cascadae peptide, however, is that it acts as a blood thinner for humans and decreases the supply of oxygen that flows in the bloodstream. A new chemical called D-lysine
was recently discovered 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 analogue
s 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.
Frog
Frogs are amphibians in the order Anura , formerly referred to as Salientia . Most frogs are characterized by a short body, webbed digits , protruding eyes and the absence of a tail...
in the Ranidae family.
It is found in western United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
and possibly Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
, mainly in the Cascade Range
Cascade Range
The Cascade Range is a major mountain range of western North America, extending from southern British Columbia through Washington and Oregon to Northern California. It includes both non-volcanic mountains, such as the North Cascades, and the notable volcanoes known as the High Cascades...
and Olympic Mountains
Olympic Mountains
The Olympic Mountains is a mountain range on the Olympic Peninsula of western Washington in the United States. The mountains, part of the Pacific Coast Ranges, are not especially high - Mount Olympus is the highest at - but the western slopes of the Olympics rise directly out of the Pacific...
.
Description
Appearance
The Cascades Frog has a green to brown color on its back and a light yellow on its throat and belly. There can be a range from just a couple to about fifty gray spots 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 point. Adult frogs will range anywhere from fifty to sixty five millimeters in lengthVoice
The advertisement call of the Rana 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.Habitat
The Cascade frog was first discovered in the Cascade Mountains in the California regions. It can be found throughout the Cascade Mountains ranging from Washington through OregonOregon
Oregon is a state in the Pacific Northwest region of the United States. It is located on the Pacific coast, with Washington to the north, California to the south, Nevada on the southeast and Idaho to the east. The Columbia and Snake rivers delineate much of Oregon's northern and eastern...
, and California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
. They concentrate heavily around the volcanic area of the peaks. Its natural habitat
Habitat
* Habitat , a place where a species lives and grows*Human habitat, a place where humans live, work or play** Space habitat, a space station intended as a permanent settlement...
s are temperate forest
Forest
A forest, also referred to as a wood or the woods, is an area with a high density of trees. As with cities, depending where you are in the world, what is considered a forest may vary significantly in size and have various classification according to how and what of the forest is composed...
s, temperate grassland
Grassland
Grasslands are areas where the vegetation is dominated by grasses and other herbaceous plants . However, sedge and rush families can also be found. Grasslands occur naturally on all continents except Antarctica...
, river
River
A river is a natural watercourse, usually freshwater, flowing towards an ocean, a lake, a sea, or another river. In a few cases, a river simply flows into the ground or dries up completely before reaching another body of water. Small rivers may also be called by several other names, including...
s, swamp
Swamp
A swamp is a wetland with some flooding of large areas of land by shallow bodies of water. A swamp generally has a large number of hammocks, or dry-land protrusions, covered by aquatic vegetation, or vegetation that tolerates periodical inundation. The two main types of swamp are "true" or swamp...
s, freshwater lake
Lake
A lake is a body of relatively still fresh or salt water of considerable size, localized in a basin, that is surrounded by land. Lakes are inland and not part of the ocean and therefore are distinct from lagoons, and are larger and deeper than ponds. Lakes can be contrasted with rivers or streams,...
s, intermittent freshwater lakes, freshwater marsh
Marsh
In geography, a marsh, or morass, is a type of wetland that is subject to frequent or continuous flood. Typically the water is shallow and features grasses, rushes, reeds, typhas, sedges, other herbaceous plants, and moss....
es generally between 665 m (2,180 ft) and 2,450 m (8,040 ft) 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.
Reproduction
Cascades Frogs lay their eggs May 20 through July 10, depending on when the snow melts and creates ponds for the eggs to hatch in. 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 twenty days. They then have a larval period which lasts eighty to ninety-five days. Most frogs will 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.Diet
Larvae are thought to be primarily benthic feeders, but specific preferences are not well known.The diet of the adult Cascade frogs is poorly known as well, but they are thought to consume a variety of invertebrate prey and will occasionally consume other frogs and tadpoles.
Population
Females have a higher mortality rate than the male Cascade, but both are believed to live over five years, sometime reaching up to seven.Recently there has been a decline in the Cascade frog species. However 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 like trout and bullfrog
Bullfrog
The American bullfrog , often simply known as the bullfrog in Canada and the United States, is an aquatic frog, a member of the family Ranidae, or “true frogs”, native to much of North America. This is a frog of larger, permanent water bodies, swamps, ponds, and lakes, where it is usually found...
s, 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 Cascade frogs, because the juveniles were not capable of sensing and avoiding toxic levels in laboratory studies.
Predation
The main predators of the cascade frogs are the, raccoonRaccoon
Procyon is a genus of nocturnal mammals, comprising three species commonly known as raccoons, in the family Procyonidae. The most familiar species, the common raccoon , is often known simply as "the" raccoon, as the two other raccoon species in the genus are native only to the tropics and are...
, mink coyote, water bugs (Belostomatidae), garter snake
Garter snake
The Garter snake is a Colubrid snake genus common across North America, ranging from Alaska and Canada to Central America. It is the single most widely distributed genus of reptile in North America. The garter snake is also the Massachusettsstate reptile.There is no real consensus on the...
s (Thamnophis sirtalis), and several bird species such as the sharp shinned hawks, owls
OWLS
OWLS is a mnemonic used by general aviation airplane pilots to assess an unprepared surface for a precautionary landing.Like all mnemonics this check has become part of aviation culture and folklore.OWLS:* Obstacles* Wind direction...
, gray jay
Gray Jay
The Gray Jay , also Grey Jay, Canada Jay, or Whiskey Jack, is a member of the crow and jay family found in the boreal forests across North America north to the tree-line and in subalpine forests of the Rocky Mountains south to New Mexico and Arizona...
s, and robins
Robins
Robins is a Swedish late-night talk show which premiered on SVT2 on August 23, 2006. The host is the young stand-up comedian Robin Paulsson from Malmö...
. The long toed salamander and adult cascadae frogs are predators to the eggs and tadpoles as well.
Pharmacology
To guard itself from other microorganismMicroorganism
A microorganism or microbe is a microscopic organism that comprises either a single cell , cell clusters, or no cell at all...
s that live in the environment, the cascade frog produces high concentrations of antimicrobial peptides that it secretes from its skin in response to infection or stress. In studies done by Conlon, it has been found that “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 in order to determine whether or not the peptides would have an effect on bacterium that attack human cells. His discovery was that the chemical Ranatuerin-2CSa, which is produced by R. cascadae, impeded the growth of E. coli
Escherichia coli
Escherichia coli is a Gram-negative, rod-shaped bacterium that is commonly found in the lower intestine of warm-blooded organisms . Most E. coli strains are harmless, but some serotypes can cause serious food poisoning in humans, and are occasionally responsible for product recalls...
and S. aureus
Staphylococcus aureus
Staphylococcus aureus is a facultative anaerobic Gram-positive coccal bacterium. It is frequently found as part of the normal skin flora on the skin and nasal passages. It is estimated that 20% of the human population are long-term carriers of S. aureus. S. aureus is the most common species of...
in humans. These anti-infective agents give the Cascade frogs “therapeutic potential for the future” according to Conlon.
A drawback of the R. cascadae peptide, however, is that it acts as a blood thinner for humans and decreases the supply of oxygen that flows in the bloodstream. A new chemical called D-lysine
D-lysine 5,6-aminomutase
In enzymology, a D-lysine 5,6-aminomutase is an enzyme that catalyzes the chemical reactionHence, this enzyme has one substrate, D-lysine, and one product, 2,5-diaminohexanoate....
was recently discovered 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 analogue
Functional analog
Functional analogs , are compounds that have similar physical, chemical, biochemical, or pharmacological properties. An example of a functional analog is morphine and heroin. Functional analogs are not necessarily also structural analogs with a similar chemical structure...
s 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.