Like the sirens to Odysseus, the frog chorus beckons me. From dusk to dawn I hear the call, pause, perk up my ears, wander towards the pond. Within a tiny plot of land, less than a tenth of an acre, an amphibian-friendly habitat exists where adults reproduce, eggs hatch, turn into tadpoles, finally form frogs. And the cycle begins again. Predators lurk and slither, hoping to make a meal out of a Pacific Tree frog. The sirens may not make the best comparison: at the end of my journey, a quick walk to just outside the limits of our fence, male frogs floating along the perimeter of the pond or near one of hundreds of cattails inflate their air sacs, then empty them with a bellow to attract females. Odysseus and his brethren faced a much more dangerous fate. As they hear my approach, they fall silent, but within minutes, my reassuring quiet allows them to begin again in a body of water that is simply a retention pond for a housing complex adjacent the Anacortes Forest Lands.
During the day, as I make my way along the edge, I rarely notice the two inch long frogs until they hop into the water, green with algae. Clumps of transparent eggs, like shiny clusters of grapes, await their transformation.
From the WSDFW site and Animal Diversity Web, I learn about these amphibians, “Outside of the breeding season, adult treefrogs inhabit a variety of habitats, including woodlands, meadows, pastures, and gardens— at times several hundred yards from water. Note: Ponds, swamps, marshes, and similar spots are used only a few weeks or months of the year; treefrogs spend the rest of the year in surrounding areas,” ” Treefrogs secrete a waxy coating from their skin glands that allows them to remain moist and travel far from water,” “Toe pads on their front and hind toes enable treefrogs to climb in search of beetles, flies, spiders, ants, and leafhoppers. Adults have been seen and heard up in trees and outside windows two stories high.””Pacific Treefrogs are the most commonly heard frogs in Washington.”
Observing them during too many trips to count over a period of months, my assumptions about what I see are occasionally right, more often wrong,
Assumption: Frogs are green. Fact: “Adults…vary in color from a bronze brown to a light lime green, and from solid in color to intricate patterns.”During my stops at the pond, I see over fifty frogs in a variety of colors and patterns and recognize some that I see repeatedly.
I photograph them in plan view, from the side, back and front. I realize through trial and error that images of these small frogs in water and land are best taken eye to eye, at their level of sight. Of the hundreds of photos I took at the pond, this one of a black-striped green frog peaking through the grass is one of my favorites.
Assumption: Piggyback frogs are adult/juvenile. Fact: “ 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,” and, “Once females lay eggs in the water, both males and females abandon the eggs. There is no parental investment.” So, this nighttime shot was not, as I thought, a juvenile on an adult’s back, but…a couple caught in the act.
Assumption: Garter snakes eat only insects. Fact: “Garter snakes are known predators of Pacific treefrogs.” The first time I noticed Garter snakes near the pond, I knew they weren’t there just for the dragonflies, water striders and spiders. I felt fear for “my” frogs, especially when one of the largest ones I’ve ever seen slithered speedily between cattail stalks across the surface of the water. From Live Science, ‘…garter snakes “feed mostly on fishes, amphibians, and earthworms; other prey are occasionally taken.” The snakes immobilize their prey with their sharp teeth and quick reflexes. The saliva of some species contains a mild neurotoxin that causes paralysis, making small prey easier to swallow. Like other snakes, garter snakes swallow their food whole, according to the ADW. [Herpetologist Jeff] Beane said “some larger prey may be dragged and chewed until killed by trauma.’
One day I noticed a salmon-colored frog standing stock still, looking…resigned? I realize that a baby garter snake, with a mouth barely large enough to encase the frog’s leg, was holding her captive. Within minutes, the tiny snake gave up and released its grip. The frog stretched her offended hind leg, leaped into the water, lived to tell the tale.
Week in, week out, happenings in the drainage were my window into the world of pond creatures. One evening I was surprised to see what turned out to be a pair salamanders mating. My excitement changed to concern when I tracked the species down and learn that the pair were Sierra newts, listed as an invasive species at the WSDFW site.
Per California Herps, “Poisonous skin secretions containing tetrodotoxin repel most predators. This potent neurotoxin is widespread throughout the skin, muscles, and blood, and can cause death in many animals, including humans, if eaten in sufficient quantity. (One study estimated that 1,200 – 2,500 mice could be killed from the skin of one California Newt.) ”
On a sunny afternoon in early April, I stumble upon a Painted turtle, the first I’ve seen on Fidalgo Island, nearly hidden in the shade of a small, grass-lined ditch that drains into the pond. According to WarnerNatureCenter.org, “Painted turtles are the most widely distributed turtle in North America. They live in permanent freshwater habitats such as ponds, lakes, marshes, sloughs, and creeks.” Fun facts, “Scientists estimate that painted turtles can live up to 40 years in the wild, but in captivity they do not live nearly as long,” “The shell of a painted turtles is made up of 13 separate bone plates called scutes. When the turtle grows, it sheds the outermost layer of these scutes and grows new, larger plates underneath. The age of a turtle can be determined by counting the rings on the scutes,” and, “Turtles have no vocal chords, but they can sometimes make hissing sounds.”
Nearly three months have passed since the first time I strolled over to the pond. As the sounds have died down, so has my interest…until next year. I’ve been lucky enough not only to observe treefrogs in their natural habitat, but also newts, insects, spiders, birds, rabbits, deer, a turtle, and plenty of plants and wildflowers. Tiny, fascinating worlds are out there…sometimes right in our own backyard.