Gull Banding at Mono Lake

Text and photos by
WILLIAM POOLE
Originally published as: “A Dream Volcano in an Inland Sea”
August 2, 1987
This World Section – San Francisco Chronicle

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Krakatoa Islet
Mono Lake
Mono County

Inside the volcano, high above Krakatoa Islet in Mono Lake, a biologist from the Point Reyes Bird Observatory and six volunteers wait out the heat of the day. It is only half a volcano, really—the front half, built out of wood and chicken wire and plaster as a stage prop for the 1955 Fred McMurray movie “Fair Winds to Java.” But it is enough of a volcano for this football-field-sized pile of rock to have been playfully tagged Krakatoa, after the Indonesian volcanic island of the same name.

David Winkler, an ex-University of California at Berkeley biologist who began studying California gulls here in 1976, built a broad treehouse-like platform inside the old structure, where researchers now eat and sleep and shelter in the open shade of the volcano’s gradually crumbling skin. There are a pair of crudely crafted work tables here, along with a bench, a planked-in area that serves as an office and several outlying sleeping alcoves, tentatively perched high above a rocky scattering of islets, thick with gulls.

I have just arrived on Krakatoa and am pleased to see that the inside of the volcano is also amply provisioned with groceries, including cheese, fresh and canned vegetables and fruit, three kinds of bread, tortillas, pasta, bulgur, dried beans, eggs, cookies, pudding, salsa, beer, wine, coffee (ground and instant), dried milk, catsup, lemon juice, olives, jalapeno peppers and a dozen tins of spices. Everything needed to amply fortify a platoon of researchers for five days.

So I am a little disappointed when Dan Rubinoff, a fresh-faced 17-year-old volunteer from Berkeley, proposes that we lunch on brine shrimp, freshly dipped from the salty lake. It is these half-inch-long shrimp (together with the black brine flies swarming everywhere at the water’s edge) that attract the gulls to this place. Tons of the shrimp are harvested from Mono Lake each year to be sold as aquarium fish food. “And while I never heard of people eating them before,” says PRBO biologist Emilie Strauss, “we tried them last night, and they were really pretty good.” Which is how I end up sitting in the hot sun on the edge of a wooden volcano enjoying the rich salty taste of the shrimp rolled into a flour tortilla with a vegetable sauté—a kind of gull-food burrito. I’m just as glad we don’t also sample the flies, although the Kuzedika Paiute, who once made their home on the shore of this lake, ate both the larvae and pupae of these insects. The Indian word “mono” means both fly people and brine fly in the language of the Yokuts, the Paiutes’ neighbors across the Sierra crest.

Emilie Strauss may be five feet tall in her black rubber boots, but it would be a close call. She is dark with watery blue eyes, and her hair is closely cropped except for a tiny braid that dangles to the base of her neck. She picked me up with another volunteer that morning on the shore of the lake, stripping the big, camera-laden pack from my hands and tossing it easily into the bow of the open aluminum boat. She had sent me a detailed map showing the pickup spot, and I had hiked down from the road in tennis shoes over the old lake bed.
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Emilie Strauss

Since the 1940s, the Los Angeles Department of Water and Power has been diverting four of the five eastern Sierra creeks that feed Mono Lake, and the lake’s volume has decreased roughly by half. Hiking from the old shoreline to the new, the ground becomes increasingly soft and springy underfoot, until I’m sinking to my ankles in a thick black ooze. It is a salty, hard-edged place, strewn with waist-high tufa: craggy limestone structures with the look of sponge and the texture of broken glass. Near the shore, the air is filled with a rich organic smell, like a mixture of barnyard and salt marsh.

In winter, I am told, this lake is pea green from the algae blooming in the cool water. But in summer, the shrimp keep the algae trimmed back, and Emilie Strauss can peruse the shallow bottom as she guides the boat around submerged tufa through a mass of swarming shrimp. She has been coming to the lake off and on since 1982, the year before the Point Reyes Bird Observatory took over the research here from David Winkler. She came first as a volunteer, then as a field biologist working with PRBO ornithologist Dave Shuford. In those years, biologists stayed at the 65-square-mile lake throughout the summer breeding season. Now workers come three times a year: in May to count and mark nests, in August to count dead chicks, and for these five days in early July to count and band the warm, mottled bundles of feathers that are the latest crop of California gulls.

Emilie is the only PRBO biologist working on the island this year. It is she who has recruited the volunteers and organized the research, she who in the afternoon sits in the volcano with a spotting scope checking the chicks on the nearest of the islets below. While the sun is high, the chicks are under stress and pant through their mouths to throw off extra heat. When the chicks stop panting, Emilie knows that it’s cool enough to go to work. At 5 o’clock, we pile in the boat with headlamps, jackets, a Thermos of coffee and a bag of sandwiches and putt-putt across the channel to the islet of Little Tahiti to go to work. As we approach, there are gulls everywhere—adults screaming from the rocks and whirling overhead, and gray chicks dabbling in the water at the islet’s edge. “These guys are getting ready to ask for the car keys,” Emilie says with delight.

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Eighty-five percent of all the California gulls that breed in the state (one-fifth of the world population) nest at Mono Lake. They fly in from the coast in April, over the snowy Sierra crest, and fly back each August—both the starched white adults and the season’s sooty young. Prior to 1979, 65 percent of these birds nested on Negit Island, over to the west. Covered with shade-producing greasewood, Negit Island was an ideal place for baby gulls. But that year the dropping lake level created a bridge of ground between Negit and the mainland, allowing prowling coyotes to cross onto the island and decimate the colony. Because California gulls are creatures of habit, returning to the same nest sites year after year, the birds have been slow to recolonize Negit Island, although the land bridge disappeared, at least temporarily, after the wet winter of 1982. Now most of the gulls nest on the hot open islets east of Negit. This year about 50,000 gulls nested at Mono Lake – a figure arrived at by counting the nests and multiplying by two.

Coyote predation is only one way the Mono Lake gulls may be endangered by the diversion of its freshwater streams. The lake has no natural outlet, and as its water evaporates, salts become concentrated in a thick chemical broth. The lake’s waters are now three times saltier and 80 times more alkaline than seawater—so alkaline that Mark Twain could assert: “You only drop the most hopelessly soiled garment into them once or twice, and wring it out, and it will be found as clean as if it had been through the ablest of washer-woman’s hands.” (Twain obviously did not try this or he would know, as any gull researcher can assure you, that garments lost to the lake come out as stiff as stalactites and thickly rimed with salt.) This unique chemistry currently works to the gulls’ advantage. Because fish cannot live here, the birds suffer no competition for the rich shrimp soup. But the water is currently evaporating faster than it can be replenished by the largely diverted streams, and the lake becomes saltier and more alkaline each decade. Should the diversions continue apace, the lake will eventually become too salty even for the shrimp and flies that are the basis for so much life here – and will quickly turn into a crystalline, sterile sea.

The Mono Lake Committee and other forces that are trying to turn the water back on at Mono Lake are engaged in an ongoing legal battle with the Los Angeles Department of Water and Power. In order to fight that battle, they need hard data on the importance of the lake to breeding birds and other life—which is one of the reasons the Point Reyes Bird Observatory has continued the gull project over the years, monitoring population changes in the face of falling lake levels and increasing salinity.

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In late afternoon on Little Tahiti, Emilie Strauss and her six volunteers prepare to band a “plot” of young gulls—a low chicken wire enclosure of about 30 by 60 feet, open at the top. Emilie Strauss knows how many nests there are on the island and in the plot, having counted them in May. By counting the chicks in the plot, she can develop a ratio of chicks to nests and so estimate the total number of chicks on the islet.

As we move onto the plot, the adult birds come up around us in a screaming storm of feathers, circling above, dive-bombing to within inches of our heads. We start at one end and move in a line, the mottled chicks, yet unable to fly, scurrying before us to the other end. Then Emilie and two volunteers named Bob Baez and Gigi Bridges sit down to band in the center of the plot, while three of us fetch them baby gulls from the milling mass of feathers. Another volunteer, Barbara Kelly, sits to one side, recording band numbers and whether or not a banded chick has ticks or wing droop, or if it chucks its latest meal out onto the bander during the process. Should this last occur, samples are collected for other researchers studying gull feeding habits and nutrition. It’s the sort of thing that happens often enough that we are all soon decorated top to bottom with excreta from one end of the gulls or another—from both the chicks and the adults overhead.

We band two plots of chicks on Little Tahiti. By the time we finish it is after 9 o’clock, and a slim slice of moon rests in the clear Great Basin sky. Then there are stars, and someone must sit in the bow of the boat and hold a lantern as we run in the dark over the calm lake to the island of Java. With the dark, the birds’ panic seems to fade. The adults lift up off the nests and hold in the sky above us—hundreds of dark shapes, dimly silhouetted against the sky.

There are no fenced plots here on Java. The goal is to band as many chicks as we can find. Dan Rubinoff and I are the catchers now, following the beams of our headlamps from chick to chick through the darkness. Some of the chicks seem asleep; most are easily lifted from among the low rocks, warm piles of feathers in our hands. The banders sit in their own circle of light, bewitched chicks staring up at their lamps. After each banding, the bird is marked on the back with a special yellow dye. Three times over the next few days, Emilie will circle Java in the boat, developing a ratio of marked to unmarked chicks, and so estimating how many chicks the island holds in all.

By midnight we are exhausted from stooping over the chicks and stumbling in the dark over the boulder-strewn beaches. So we put out the lights and sit for a while drinking coffee and eating sandwiches, listening to brown feathered shapes scurry around us in the dark and the occasional passage of a big gull overhead, its wings thwup-thwup-thwupping the night air. I am a one-day volunteer and will be leaving in the morning. Most of the others are running on three hours of sleep after banding the night before, and I can only imagine their exhaustion.

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But there is a unique trade-off here. Excepting the researchers, no one is allowed on these islands during the spring and summer months. The chance to glimpse a sunrise from an improbable treehouse perched high above 50,000 nesting gulls, to make close contact with a warm, wild creature on its home ground, to catch the dark east face of the Sierra across the glassy surface of the lake, is a gift of pure magic, worth much more than a few hours of lost sleep.

Besides, it will be a relatively early night. By 2 o’clock Emilie Strauss will be ferrying the first boatload of volunteers back to Krakatoa. By 2:30 she will have returned, and we will once more be moving across the dark lake toward the looming silhouette of the volcano, improbably perched, as if in a dream, beneath an overarching spectacle of stars.

© 2017 William Poole—text and photos

William Poole’s Detour’s feature appeared between June 1987 and December 1990 in the This World section of the San Francisco Chronicle Sunday edition.

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