Once, some people believed that if you made a wish after seeing the first frog in the spring, the wish would come true, and that frogs were possessed by the souls of dead children, so killing a frog could bring bad luck. We've passed that stage ( at least when it comes to frogs ), opting for smiles rather than superstitions when we hear the frog chorus.
Traditionally called Pacific tree frogs ( although they aren't true tree frogs ), they're more accurately called Pacific chorus frogs, having been reclassified from the genus Hyla ( true tree frogs ) to Pseudacris. The Washington native is not the spring peeper, a different species that's found in the eastern United States. Very small ( up to 2 inches ), often green ( can be other earth tones ), they sport black stripes running in front of around the eye's and down to the shoulder.
Males are heard croaking in nearby water filled depressions, ditches and small fresh water ponds, sending out their come-hither messages. Males might even butt heads and kick each other with their feet to chase rivals. After mating, the frogs can be found far from water. They have been seen crawling up the side of a house and hanging around in a metal bin, also have been found in hot tubs.. The can stay away from water because they have skin glands that secrete a waxy coating.
Pacific chorus frogs also provide soundtracks for scores of movies, cartoons and TV ads, the familiar " rib-bet, rib-bet, rib-bet " that call has been heard in films set in Africa and on alien planets, even though these frogs are only found along the western side of North America.
While the " rib-bets " are used in January, February and March, a one syllable call is used the rest of the year. They make sound basically the same way we do, except they keep their nostrils and mouth closed so the air flows over vocal chords and into the vocal sac, puffing it up like a balloon. The sac amplifies a certain frequency and broadcasts the sound.
Led by a chorus master, the vocal marathoners expend massive amounts of energy singing hour after hour, night after night. Just ask a resident who lives near a chorus, people have been known to fill in a pond to get rid of them. It's possible to hear them a mile away on a quiet night, and if, theoretically, you could put your ear next to one, " rib-bet " would sound as loud as a jackhammer.
Female frogs orient better to a chorus than to the call of one frog.. The males make shopping easier by gathering around twilight. It's the concept of a selfish herd, a frog in a chorus has a lower chance of being picked off by a predator. Females apparently prefer choruses of males over single males, even walking right by a single male to reach a wider choice. Males can call a few thousand times a night while females sample the calls.
Loudness reflects the males size, attractive to a female. She swims up to her choice, nudges him if he's caught up in croaking. They engage in a several hour mating process that includes laying jellylike egg clusters on plants, eventually laying 500 to 750 eggs.
A few weeks later, depending on water temperature, tadpoles emerge, two months later, metamorphosis produces frogs, who will join the chorus next year.
