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PAINTED WINGS Berkeley’s School of Rock Habitats and Humanity Savoring Salt Point $5.95
Mapping Murrelets
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Marbled Murrelets, Mariners of the Old-Growth U.S. Fish & Wildlife Service
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from their nests in old-growth forests to the ocean to forage for small fish like anchovies and sardines. (right) Steve Singer tracks murrelets for the Sempervirens Fund. (below) Singer has mapped several murrelet flyways, though he’s careful to note that not all murrelets use these particular flyways, and some may nest far from the flyways he’s found. Loma Mar Pescadero
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(above) Marbled murrelets fly daily
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From Sempervirens Fund, 2010. Sources: USGS, ESRI, CPAD, Steve Singer
This is a story about a little-known bird that’s no owl, eagle, or peacock. It‘s not featured on a stamp or in a Disney cartoon. Most people haven’t heard of it and can’t even pronounce its name. But dig deeper into the “marbled murrelet” (that’s MER-let, not mure-a-LET), and you’ll find a story of scientific mystery and dedicated people working to help an increasingly scarce bird and its habitat. Part of the auk family, which includes puffins, razorbills, and auklets, murrelets dive underwater in the ocean to feed on anchovies and sardines. What makes these birds special, however, is that while all other auks nest on seaside cliffs and bluffs, the murrelet nests inland in old-growth redwoods and Douglas firs. So I meet environmental consultant Steve Singer far out of sight of the ocean, at the Gazos Mountain Camp in Butano State Park in the Santa Cruz Mountains. A white-bearded former ranger, Singer points up to the thousand-year-old trees and explains that murrelets look for wide, flat-topped, mossy branches with grooves to cradle their pale-
green, brown-spotted eggs. The nests seem hard to reach even for the birds: “This bird is not adept at landing because of its webbed feet,” says Singer. “Sometimes they miss the landing strip completely, circle back and try again.” Ornithologists once considered the whereabouts of those nests “one of the last great ornithological mysteries in North America.” Then, in 1974, a pruner named Hoyt Foster was working at nearby Big Basin Redwoods State Park. At 150 feet up in an old Douglas fir, he came across an odd-looking, football-shaped bird. He called a ranger, who wrapped the bird in a T-shirt and set it in a cardboard box. Other rangers, including Steve Singer, stopped by to take a peek. They realized that Foster had become the first person to discover a murrelet nest. Seeing a murrelet nest is almost impossible, and spotting adults out of
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the nest isn’t much easier. The males and females share nesting and chick-rearing, and each dawn and dusk, one of them leaves to hunt at sea, while the other stays to incubate their single egg. To see the changing of the guard, you must rise before dawn and sit in the cold for hours, only to glimpse a blurry spot streak by at breakneck speed — murrelets often fly at 50 miles an hour and have been clocked at 103. Singer spends a lot of early mornings here as part of a research effort begun in 1998. In the late 90s, the Sempervirens Fund, a land trust focused on the Santa Cruz Moun-
Kris Vann
by kris vann
Glenn McCrea, dewdropworld.com
on the trail
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STORIES IN STONE by Doris Sloan
Waves crash on the rocky shore, salt spray flings high into the air; pelicans and cormorants skim the water in single file; in spring whales spout offshore and wildflowers blanket the marine terrace. The stunning beauty of Salt Point State Park, about 90 miles north of San Francisco, is reason enough for a trip up the coast. Add an underwater reserve, spectacular rock formations, and an unusual white sand beach for an exceptional coast experience. Salt Point State Park stretches for six miles along the rugged northern Sonoma coast, from Wildcat Creek to Horseshoe Cove, and its 6,000 acres cover diverse landscapes that range from the rocky intertidal at the shore to grasslands on 10
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the marine terrace to a pygmy forest of stunted cypress, Bishop pine, and redwoods on the ridge to the east. Though the park is best known for its underwater reserve and splendid tide pools, to a geologist the main attraction is the incredibly beautiful rock forms exposed along the shore. The landscape here is formed by two dominant geologic processes: plate tectonics and wave action. As such, it’s a showcase for two of the major forces shaping our region. The San Andreas Fault, which forms the boundary between two of the earth’s great tectonic plates, lies just east of the park near the crest of the ridge. Along the fault, the Pacific Plate is sliding
northwestward past the North American Plate. To the south the fault cuts across Bodega Head, then runs offshore and comes back on land near Fort Ross, 15 miles south of Salt Point. It goes out to sea again at Point Arena, about 50 miles to the north. Salt Point, then, lies west of the fault, on the Pacific Plate. This area, part of what’s called the Salinian Block, has been carried about 250 miles northward from its origin in Southern California. Fault movement has also tilted up and folded the rocks from their original near-horizontal position. The rocks are much older than the landscape, some as much as 60 million years old, and formed under geologic conditions vastly different from today’s. In looking at the geology of the park, as elsewhere, you need to think in terms of two different time scales: the age of the rocks and the processes that formed them, and the present landscape and the processes that shape it today. Here, those processes couldn’t be more different.
habitats of
the East Bay Regiona l Parks This story is part of a series exploring significant natural habitats and resources of the East Bay Regional Park District (EBRPD), many of which are encountered in other parts of the Bay Area as well. The series is sponsored by EBRPD, which manages 65 parks, reserves, and trails covering more than 100,000 acres in Alameda and Contra Costa counties (ebparks.org).
by Kathleen M. Wong
H
abitat and Managing
Rare Species
in the Metropolis To take in the view east from the top of Briones Peak, south of Martinez, is to drink in the iconic glory of California’s inner Coast Range: Velvet grasslands, colossal oaks, and shady ravines of bay laurel extend for hundreds of acres in every direction. It can seem as if little has changed since the Spaniards first arrived and claimed these hills for their ranchos.
(above) Arrowhead Marsh at Martin Luther King Jr. Regional Shoreline is important habitat for endangered California clapper rails, but it’s also wedged between the Port of Oakland and Alameda and has been invaded by aggressive hybrid cordgrass. (left) Endangered California least terns nest on an artificial island at Hayward Regional Shoreline. Tern monitors watch David Riensche, East Bay Regional Park District
the colony through birding scopes, using numbered markers to track nests. (far right) The endangered Presidio clarkia survives only at the Presidio in San Francisco and on grassland in the Oakland Hills.
Jerry Ting
But look more closely and you can’t help but notice the human hand in almost every part of this landscape. Roaming the fields are cattle that graze down European grasses and, it turns out, make room for native wildflowers. The ponds that dot the meadows were built for cattle but now are also maintained as habitat for rare tiger salamanders and red-legged frogs. In the Bay Area, wilderness is almost always surrounded by intense human activity. That’s especially true in the East Bay, home to 2.5 million people — a third of the Bay Area’s human population — and more than 100,000 acres of land managed by the East Bay Regional Park District. The district is the East Bay’s largest owner of protected lands, and its staff works to give imperiled species a helping hand. Sometimes that simply means monitoring rare habitats, but it can also mean felling trees for the benefit of a native wildflower or even creating an artificial island for breeding birds. “Doing nothing is not an option anymore in a lot of areas,” says biologist Stuart Weiss with the Creekside Center for Earth Observation, which has worked on key habitat projects for the
district. “The age of fencing areas off and letting them take care of themselves — those are long gone if they ever existed. So finding ways to have very careful stewardship and management is going to be absolutely essential over the long run if we’re going to preserve biodiversity.”
Lech Naumovich
Humanity
An Island for Terns The shoreline of San Francisco Bay has been among the habitats hardest hit by civilization. Over the past 150 years, more than 90 percent of the tidal marshes and beaches that once encircled the Bay have been lost to diking and development. That’s been bad news for the California least tern, whose backswept wings make it look like an avian version of the Concorde jet, topped by a black cap with a white forehead stripe. This federally endangered species nests on open beaches and sandy spits, but these habitats are now vanishingly rare both j u ly – s e p t e m b e r 2 0 1 0
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first came to understand the rock called Northbrae rhyolite on a sunny afternoon 17 years ago. I was a bored and dorky teenager looking for adventure, and I had taken up rock climbing at a small city park in the Berkeley Hills called Indian Rock. I was milling about with a few other climbers when a muscle-bound crowbar of a man with long black hair and dark features approached me and offered to show me a climbing route—he called it a “problem,” climbing jargon for short ascents done without ropes. He led me to the highest point on the rock where, though the climb was short, the fall to the ground was two and a half stories. As a gangly kid still waiting for my voice to change, I was awed as this chiseled daredevil traversed the rock face, casually defying gravity. So I followed him. Halfway through I realized I had bungled the sequence—put my right hand where my left should have been. I panicked, froze, and began to shake. Tenuously, with my feet hanging over a leg-breaking fall, I scrabbled my hands into different positions and somehow finished the problem, pale and trembling. “Cool, right? Kinda tricky in the middle there, huh?” was all he said. Damon Tighe inset: Courtesy Colby Memorial Library, Sierra Club I later learned my long-haired mentor was Dan Osman, a world-famous rope-free climber who If you have been to the Berkeley Hills, you have probably eventually died in a tragic (if predictable) accident. seen Northbrae rhyolite. It’s in the rock walls and the distinctive And though I never did that problem again, it turns pillars marking street corners. In some cases it appears as a dishout that I was not the only confused kid who found water blonde rock seeming to grow right out of the side of a house. The most distinctive example, though, is Indian Rock purpose and guidance on those rocks. In fact, two in the middle of North Berkeley. groups of Bay Area pioneers have visited these and Rhyolite forms from a viscous sort of lava belched from very other related rocks for over a century, squeezing from explosive eruptions. Berkeley rhyolite comes from two eruptions them lessons about discipline, strength, and how to that happened about 9 and 11 million years ago — one in the Berkeley Hills and the other probably somewhere near what is observe the natural world. 24
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GE OLOGY
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(left inset) Mountain climbing pioneer Dick Leonard leaps from Indian Rock in the 1930s. (above) Today the rocks remain popular with climbers, some just learning and others practicing for bigger ascents in the Sierra Nevada and beyond. (right) Kite aerial photo of Indian Rock, the largest of many rocks now incorporated into the residential fabric of North Berkeley.
now Fremont. Each eruption left thick layers of lava, which cooled and were covered by other layers of lava or sediment that were twisted by fault movements with the surrounding darker basalt, like the vanilla in a chocolate/vanilla swirl pudding. To learn more about these rocks, I joined UC Berkeley
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