Where history comes to the surface
They range from simple ancient shells embedded in sandstone to rare bones of extinct whales. Many tales of finds are coming in after last week’s story on how December’s pounding winds and rains had unearthed fossils in the region.
Many have also asked where they might see examples of embedded fossils in regional parks in the Bay Area. There are many sites.
The most provocative find, an impossibly rare fossilized inner ear bone of an extinct whale, was certified by the California Academy of Sciences. It was found in the East Bay hills on watershed land managed by the East Bay Municipal Utility District, roughly near where Pinehurst Road feeds into Canyon Road near Moraga, reported a longtime Chronicle field scout who goes by Gambolin’ Man, a.k.a. Tomario, and runs an excellent adventure website at http://gambolinman.blogspot.com.
At first look, the object appears like a cue ball — smooth, white and round. It was turned over to the Academy of Sciences and found its way to anthropologist Russell
Hartman for identification. “I showed your found items to several people from other departments, and the consensus is that the spherical piece is the ear bone from a whale, although it would be difficult if not impossible to say which whale,” Hartman wrote.
Many regions of the Bay Area were once the sea floor, sprinkled with shells, and the bones and teeth of ancient and extinct marine mammals and sharks. Uplifting, subduction, other geologic factors and sea-level changes mean you might be living on what was once the bottom of the ocean.
On the Peninsula, for instance, gardeners often find small shells, often resembling those of conical sea snails, when tilling soil. Tropicaltype fossils discovered in sandstone formations in the San Francisco and Marin headlands have provided evidence of very warm seawater during an ancient period, according to the Golden Gate National Recreation Area.
In the East Bay hills, you can often find fossilized shells in sandstone outcrops. The three best places are:
Summit Visitor Center, Mount Diablo State Park: The building is made, in part, from sandstone blocks excavated from the area; look for the ocean fossils, some 15 million years old, in the exterior walls. (925) 837-2525, www.parks.ca.gov.
Shell Ridge Open Space, Walnut Creek: If you explore the ridge and look for the rock outcrops, you can find marine fossils embedded in the sandstone, from when this area was the bottom of the ocean. (925) 943-5800; www.walnut-creek.org.
Flag Hill, Sunol Regional Wilderness: An 800-foot climb on Hayfield Road leads to Flag Hill, a rock outcrop that towers over the Sunol Valley. At the summit, scan the rocks closely for all manner of small ancient sea fossils. (888) 327-2757, option 3, Ext. 4559, www.ebparks.org.
Another good site is along the Las Trampas and Bollinger faults near San Ramon, where uplifting has brought ancient beach remnants to the surface of the foothills.
Near Dublin, we also found fossils in the rock outcrops along Calaveras Ridge. www.ebparks.org.
Record trout
David Bixler of San Jose caught a lake-record, 13.72pound rainbow trout in Los Vaqueros Reservoir last weekend while fishing with a Kastmaster from the South Cove shoreline. The giant trout measured 30 inches long.
“I knew I had something big on the line,” Bixler said. “I shouted to my friend to grab the net.”
Los Vaqueros has become the Bay Area’s No. 1 fishing lake as it continues to mature with a rich aquatic food chain and high fish populations. With its new, raised dam, the lake is 71 percent full with good clarity and a 61-degree water temperature.
Info: (925) 371-2628, www.ccwater.com/losvaqueros
Birds never lie
I’ve long held that you can predict massive weather phenomena by watching birds, and ecologist Henry Streby at UC Berkeley found that birds will flee — even leaving their nests — one to two days ahead of the arrival of a large storm.
In the Bay Area, when gulls leave the coast and take up residence at Crystal Springs Reservoir (and other inland lakes), it means a big storm with horrific winds is imminent. But in the spring, when snow geese leave en masse from the Sacramento National Wildlife Refuge near Maxwell and the sandhill cranes depart from Woodbridge Ecological Preserve near Lodi, it means the change of seasons is at hand and expect no more big rains.
Q&A
Q: “You stated that Shasta Lake gets most of its water from rainfall. Several of us thought it was snowmelt from the mountain and foothills that went into the lake. Could you please clarify this for us?” — Gayl, Natural Science Gallery Oakland Museum
A: Depending on the year, California’s largest reservoir is filled by 70 to 90 percent rain and 10 to 30 percent snow, just the opposite of High Sierra lakes. In the past 30 days, the lake level has risen 53 feet.
Notes
From the duck blind: Robert Larkins was in his duck blind with his dog, Katie, a Labrador, when 28 tule elk “came right through our pond, 25 yards from the our blind.” As Bob tells it, he looked at Katie, and Katie looked back, as if asking, “What kind of ducks are those?”
Murrieta flows again: It can be the Bay Area’s most frustrating waterfall — a challenging 12.25-mile round trip hike in the Ohlone Wilderness to a site that is often dry or only a trickle. It has been recharged by December rains, reports trail runner Tom Riley, who ran a 16-mile loop with a 5,000-foot cumulative elevation gain to see it.
Mushroom alert: The number of mushrooms popping up across much of California is amazing. Sandra Turnbull writes that she has seen visitors picking them at parks, an act subject to a ticket.
Free of charge: Get set to check out the National Wildlife Refuges. Admission will be free on Jan. 19 (Martin Luther King, Jr. Day) and Feb. 14-16 (Presidents’ Day Weekend). Do they know any better: “You wrote an article about the Golden Gate Bridge in which you stated that pedestrians were on the east side of the bridge, and bikes on the west. This year, I have had an occasion to take several friends to walk the bridge, and it has been an absolute nightmare with many, many recreational bikers on the east side mixing with the pedestrians. What an absolute mess, and an accident waiting to happen.” — Dee Cunningham