This Article Has Been Published in Oceanography, Volume 23

This article has been published inOceanography , Volume 23, Number 2, a quarterly journal of The Oceanography Society. Copyright 2010 by The Oceanography Society. All rights reserved. Permission is granted to copy this article for use in teaching and research. Republication, syst- emmatic reproduction, or collective redistirbution of any portion of this article by photocopy machine, reposting, or other means is permitted only with the approval of The Oceanography Society. Send all correspondence to: [email protected] or Th e Oceanography Society, PO Box 1931, Rockville, MD 20849-1931, USA. Ripple Marks The Story Behind the Story BY CHERYL LYN DYBAS Canyon “Ghost” Critical to Stream Ecosystems: Cougars Act as Guardians of Fish, Frogs The ghost cat, it’s been called, this feline By doing so, the cats, it turns out, served as somewhere we couldn’t view. Maybe that that roams backcountry from the Yukon to sentinels of Zion’s aquatic life. But that was was wishful thinking.” Chile. It has dozens of names, from panther, once upon a time. The scientists’ study showed that cougars to puma, to mountain lion. But its best The cougars have been chased away. not only have direct effects on populations descriptor, perhaps, is cougar. Increasing numbers of human visitors at of animals such as deer and elk, but also The word comes from a term meaning Zion ran the cats out of territory they indirectly affect entire ecosystems. “false deer,” an ancient phrase coined by the once claimed. Without cougars, deer dramatically Tupi. These long-ago Amazonians, according “The loss of a predator such as the cougar increased, leading to loss of the riparian to Jerry Kobalenko in his book Forest affected a range of other species,” says cottonwood trees deer love to nibble on. Cats of North America, had an instinctive ecologist William Ripple of Oregon State Lack of cottonwoods, which serve as river- understanding of a modern scientific idea: University (OSU). Along with Robert Beschta, bank anchors, resulted in extensive erosion. a predator evolves to blend into the habitat also of OSU, Ripple conducted research on Biodiversity in Zion’s waterways plummeted. of its prey. the importance of Zion’s cougars. “’What It’s known as “the ecology of fear.” Nowhere is that truer than in the cougars?’ we should ask,” says Ripple. “The When cougars aren’t around to strike fear burnished canyon country of Utah’s Zion entire two years we were out there, we didn’t into the hearts of deer, the deer venture into National Park. Here in the recesses of Zion’s so much as glimpse a cougar. We always felt open spaces. In Zion, says Ripple, deer are redrock ravines, cougars hunted mule deer. like one might be watching us, though, from eating young cottonwood trees almost as 10 Oceanography Vol.23, No.2 “Wavelet” Math Translates Whale Song into Art fast as the trees can sprout. Floodplains Wavelets, they’re called, but they’re not the kind that gently lap have disappeared, and with them fish, onto shore. These wavelets create a kind of science-art, one that amphibians, butterflies, wildflowers, depicts the haunting songs of whales and dolphins. and countless other animals and plants. In this setting, wavelets are mathematical functions that “It’s the old adage we learned in parse data into different frequencies. “They have advantages our first ecology class: everything is over other methods of analyzing signals with sharp spikes,” says connected to everything in nature,” says Mark Fischer. Such spikes, he says, are characteristic of whale biologist Howard Quigley, an expert and dolphin music. on cougars and director of Western Fischer should know. An expert in marine acoustics, he owns Hemisphere Programs for Panthera, a San Francisco company called AguaSonic Acoustics. Through an organization whose mission is to AguaSonic, Fischer has produced strikingly beautiful ocean art protect the world’s 36 known species of that comes not from a paintbrush, but from cetacean songs. wild cats. “The presence of carnivores Using wavelets, the engineer, who once developed software for like cougars has impacts we’re just now the Navy, translates whale and dolphin communication into scratching the surface of.” illustrations that look like starbursts and solar flares. Ripple and Beschta compared a “Wavelets capture intricate detail without losing the larger canyon in the national park itself—Zion picture,” says Fischer. “When you show them in a circular form, Canyon—with one in a nearby roadless patterns become very clear. Certain sounds are unique to watershed. The “other canyon,” called different species of whales and dolphins. Wavelets allow us to North Canyon, is far off the beaten create an auditory fingerprint.” path. Zion Canyon receives some three To visualize the clicks and whistles of whales and dolphins, TOP. Echo-location clicks million human visitors each year; North marine scientists usually develop spectrograms, graphs of the made by an orca recorded Canyon, only a few stray hikers. frequencies of vocalizations over time. “But spectrograms are by Paul Spong in Johnstone Strait (Vancouver Island, North Canyon is home to a thriving created with what’s known as Fourier methods,” says Fischer, BC, Canada). Each cougar population, hence has fewer “better suited to repetitive, continuous sounds like whirring radial is the actual click. mule deer. In contrast to Zion Canyon, propellers than to staccato cetacean harmonies.” MIDDLE. Clicks made by a white-beaked dolphin says Ripple, “rivers in North Canyon Ten years ago, he traveled with researchers in Baja California recorded near Iceland. have 50 times more young cottonwood to take a closer look at whales’ intricate underwater commu- BOTTOM. Depicted is trees—and lots of the water-loving nication. The trip was a springboard for his now decade-long about a quarter-second of the enigmatic “boing” plants that stabilize streambanks, project. “I’d like to bring scientists and the public into a world made by a minke whale. provide food-web support, and protect they might otherwise never experience,” says Fischer. BACKGROUND. One floodplains.” The US Navy was one of his first targets. “They were inter- of the lower ‘rumbles’ made by a humpback. Restoring the cougar population ested in knowing whether beaked whales were in a certain Courtesy of Mark Fischer, to Zion Canyon might—in time— area,” says Fischer, “so I created ‘soundprints’ of the whales AguaSonic Acoustics rebalance its ecosystem. in that region. The soundprints were used to make a map of Then a phantom cat would again likely whale locations.” stand guard over rushes and willows, Mandalas, Fischer calls the prints, from the Sanskrit for concentric diagrams. red-spotted toads and cardinal Take his spiky mandala named “Rasmussen albirostris.” It shows sounds from a white- flowers—and us. beaked dolphin off the coast of Iceland. “Each spoke on the wheel is an individual click,” says Fischer, “captured in extraordinary precision.” Another mandala, “Minke punaluu,” is made up of kaleidoscopic whorls upon whorls. LEFT. Cougar: canyon country sentinel. They represent the song of a minke whale northwest of Hawaii. “Open-ocean fishermen Photo credit: S. Winter/Panthera RIGHT. (top) Stream channel and floodplain often heard these whales’ eerie cries,” says Fischer. “Although they knew the sounds came conditions along North Creek in 2005, an area from a ‘fish’ of some kind—they called it the ‘guitarfish’—no one ever saw what was doing in North Canyon where cougars are common, the strumming.” Scientists eventually identified it as a minke whale. and (bottom) the North Fork of the Virgin River in Zion Canyon, an area where cougars “With the fancy structure of whales’ and dolphins’ music, there must be more to it are rare. North Creek is well vegetated with than simple messaging,” says Fischer. “Cetaceans are always inventing new songs, so some- stable banks, while the North Fork of the thing’s going on. Unlike us, maybe their ‘ornamentation’ is inside rather than outside.” Virgin River has a lack of bank vegetation and a wide active channel with banks continuing Humans, he says, are far from the only artists on the planet. to erode. Photos credit: William Ripple Fischer’s mandala soundprints may be experienced at http://aguasonic.com. BACKGROUND. Cougar in canyon. Photo from ThundaFunda.com Oceanography June 2010 11 RippLE MArks, ContinuED Fire in the Sky, Smoke in the Water: Queen of American Lakes Under Siege from Fireworks Displays? A few Sundays from now, Americans across There are no federal or New York State Perchlorate-free fireworks are available, the nation will look skyward, awed by Fourth drinking water standards for perchlorate, but at a higher cost than traditional fire- of July fireworks displays. If those fireworks however, a particular concern for Lake works. “Since perchlorate has implications for explode over lakes, rivers, and other water- George. Residents of nearby towns and human health, a switch to perchlorate-free ways, the scene might not be so pretty. villages get water straight from the lake for fireworks could be considered,” says Lender. What goes up must come down. And drinking, bathing, cooking, and other uses. An e-mail message to the LGA from Todd it’s coming down laden with chemicals like “Part of the problem,” says DeBolt, “is that Earl, president of the Adirondack School perchlorate, a propellant used in fireworks. there isn’t much agreement on what is or Counselor Association, reflects a growing While most of the perchlorate combusts, isn’t a safe amount of perchlorate.” concern among Lake George residents. “I all of it does not, with perchlorate raining In January, LGA issued a report on prelim- understand and appreciate the tourism- over the land—and water. The water may be inary research it conducted in Lake George: driven economy of our community,” he where the problem lies.

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