Breeding occurs seasonally for Pacific tree frogs and typically occurs from winter to spring. This species is polygynous. During the breeding season, males often are found near small bodies of waters, particularly ponds, where they begin to sing. Females are attracted to males based on their calls and their different colored throats. Females prefer males that initiate calling. Once attracted, females move towards males. Males continue calling for several minutes, followed by several minutes of silence. Males continues this pattern until females are in their immediate vicinity.
Mating System: polygynous
Pseudacris regilla attracts mates using a choral song. Males call to females as loudly as possible and produce a croak so loud that they sound as though they are produced by multiple males. These sounds can be heard by numerous females. Once a female approaches, the male stops singing and attempts amplexus, a pseudocopulation act during which the male grasps the female with hist forelegs. Breeding takes place at night, near shallow water, typically after rainfall. Mating season usually extends from December to May, although some variation occurs. Altitude often affects the length of the breeding season.
Male Pacific tree frogs are occasionally aggressive during breeding season. They produce a warning call if another male approaches too closely. If the intruding male does not leave the area, the two frogs may fight until one departs. In addition, while attracting females, males can extend vocal pouches on their lower jaw, which helps in calling females. The act of copulation takes place in water. They are oviparous, and once the female enters the water, the male grasps her and helps to thrust out the eggs as he fertilizes them. Eggs are laid in small ponds or puddles. Typical broods range from 5 to 70 eggs. A jelly-like substance is left with the eggs to maintain moisture. Eggs remain in shallow water, often near twigs or leaves. Once reproduction is complete, both the male and female leave the water. Eggs hatch in three to four weeks, and within three to seven days, offspring develop into tadpoles. Development time varies with the temperature of the environment. Once they emerge from the egg, offspring use the jelly-like substance carried with the egg to sustain them for the first two to three days. Tadpoles then swim to shallow waters and ingest nearly any edible food item. When tadpoles reach three months of age, they metamorphose into froglets. This typically occurs between July and September.Research shows that as water temperature increases, development time decreases. In general, Pacific treefrogs reach sexual maturity in 1 to 2 years.
Breeding interval: Pseudacris regilla breeds once per year.
Breeding season: Pseudacris regilla breeds from January to May.
Range number of offspring: 5 to 70.
Average time to hatching: 3.5 weeks.
Average age at sexual or reproductive maturity (female): 1 to 2 years.
Average age at sexual or reproductive maturity (male): 1 to 2 years.
Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization (External ); oviparous
Once females lay eggs in the water, both males and females abandon the eggs. There is no parental investment.
Parental Investment: no parental involvement
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