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A tale of two species, and a lagoon

It’s unlikely that the Sharp Park Golf Course will revert to natural parkland any time soon now that San Francisco’s mayor vetoed a proposal to turn it over to the National Park Service.

But the final chapter in the story that’s pitted environmentalists against golf enthusiasts has yet to be written. Two species living on the golf course – the endangered San Francisco garter snake and the threatened California red-legged frog – are the subject of a federal lawsuit scheduled for trial in July.

That suit, brought by the Sierra Club, the Center for Biological Diversity, and four other groups, seeks to shut down golfing operations on until the city obtains federal permits to allow the killing of a certain number of protected species. San Francisco is now seeking to obtain those permits, which involves making changes to the 18-hole golf course designed to improve snake and frog habitat.

In the meantime, the future of Sharp Park remains in limbo. San Mateo County has offered to take it over, since the 417-acre property, though owned by San Francisco since 1917, is located in Pacifica. What makes the property so contentious are its ecological characteristics.

The low-lying park is at the terminus of the Sanchez Creek watershed, which makes it a natural wetland and ensures a constant influx of freshwater. That’s great for the San Francisco garter snake and California red-legged frog, which make their home in a non-tidal lagoon called Laguna Salada. The frogs lay their eggs in the lagoon, while the snakes use the freshwater habitat within the park to hunt Pacific tree frogs, and later in the season, the red-legged frogs.

But the set-up is bad, in a sense, for golfing. The golf course, including the lagoon, must be pumped in order to keep several fairways from flooding during the rainy season. The question is: can golfing and the two species coexist?

“I can’t say golf is perfect for the species, but it’s not what it’s being made out to be,” said biologist Karen Swaim. “The data shows that snakes, frogs, and golf can happily co-exist.”

Swaim, who has studied the snakes and frogs for the San Francisco Recreation and Parks Department, said most of all, the two species need a freshwater ecosystem. Pumping the lagoon and maintaining a seawall to the ocean emphasizes the park’s freshwater character, she said.

snake

Photo by Gary Nafis

Swaim counters that there are better places to focus on restoration of the two species, such as an area with freshwater ponds and water holes in the Calera Creek watershed, south of Sharp Park.

But coastal ecologist Peter Baye said the lagoon is the key ecological characteristic of that site. If the pumping were stopped, water levels in the lagoon would rise 4 to 5 feet and the lagoon would creep outward.

A bigger lagoon would help the species survive a big wave that comes in from a large storm, which can surmount the seawall to flood the lagoon. Thirty years later, he said, snake populations are just recovering from a 1982 event, but a crash is bound to happen again.

“The snakes will live until the next big storm,” said Baye, one of the lead authors of a study sponsored by environmental groups published earlier this year. “The lagoon now is the bottom of a basin, a vessel ready to be filled.”

He said a full lagoon (one that hasn’t been pumped) would allow less saltwater into the park during a major overwash event, ensuring a less shocking uptick in salinity, which can be deadly for the frogs and snakes.

“We need to plan in or around those long-term dominant hydrological events that define the lagoon’s ecosystem,” said Baye.

In the end, the future of Sharp Park may be determined by forces outside politics and the courts. Arthur Feinstein, chairman of the San Francisco Bay chapter of the Sierra Club, said Sharp Park is in the path of sea-level rise. Forget the freshwater lagoon, Sharp Park could become marine habitat.

“Even without litigation, the golf course is in a tough place,” said Feinstein.

Supes to decide on Sharp Park today; then to Mayor’s office

The federally-endangered San Francisco garter snake (SFGS) and its food of choice, the federally-threatened California red-legged frog (CRLF), may get new landlords at their beachside wetland home, the 417-acre San Francisco-owned and -managed Sharp Park in Pacifica, if the San Francisco board of supervisors passes legislation today that would clear the way for a transfer of its management to the National Park Service.

The ordinance, introduced by San Francisco Supervisor John Avalos this September, would compel the city to offer management of Sharp Park to the National Park Service’s Golden Gate National Recreation Area, which manages nearby Mori Point and Sweeney Ridge.

“This ordinance,” said supervisor Avalos as he opened a preliminary subcommittee meeting on Monday that passed the ordinance to the full board to discuss today, “is a way to move forward with possible changes in how we manage the park,” to thunderous applause from at least half of the 200 or so people packed in the chambers at San Francisco City Hall.

The meeting was the last chance for public comment on the contentious legislation before it enters the city’s hands. Dozens and dozens and dozens spoke for and against, in about equal measure, the legislation.

If passed, the ordinance would compel the city to offer the park’s management to the Golden Gate National Recreation Area, curtailing other plans for the park like the San Francisco Recreation and Park Department’s current plan [see attached 18-hole option of the 2009 tetratech report], adopted by the city in 2010, to keep the 18-hole golf course with some measures to enhance SFGS and CRLF habitat.

The critters currently share the park, and the marshland of Horse Stable pond and the Laguna Salada, the animals’ most critical habitat at the site, with an 18-hole golf course built in 1932 and designed by Alistair MacKenzie, who also designed Augusta National.

The nearby restored SFGS and CRLF habitat at Mori Point leads to unavoidable conflict, said Peter Baye, lead author of a 211-page report, commissioned earlier this year by the Wild Equity Institute and the Center for Biological Diversity. “The species are not going away. So, be aware of that,” he told the subcommittee supervisors, “Mori Point has embedded suitable habitat next to problematic habitat.”

That problematic nature of the habitat has to deal with a pumping system that maintains an artificially low lagoon level to keep some fairways, which regularly flood, dry; golf maintenance, which includes mowing into marshland habitat, as the report explains, that cuts into natural marshland indicated by species like brass-buttons, bulrush, silverweed and creeping bentgrass; and the “coastal squeeze” by the course of the Laguna Salada toward the beach seawall that makes SFGS and CRLF habitat precariously in line of salt-water overwash.

The pumped, low-water lagoon also encourages tule-cattail stands that shade out swaths of marshland that the SFGS uses to forage for CRLF tadpoles, one of the species’ major food sources. The SFGS also needs upland, dry habitat to breed, which some bordering golf holes take the place of. Some of these concerns have been addressed by the current SFRP plan, which would keep the 18-hole golf course and leave the seawall to nature.

Today, the legislation faces the full 11 commissioners at the supervisors’ weekly full board meeting. The ordinance passes with six or more votes. If it does, there would be a pro forma reading of the ordinance at the next supervisors’ full board meeting on Tuesday, December 13. Then it would head to Mayor Lee, who can sign it into law or veto it.

Humpbacks Make Rare Near-Shore Visit in Santa Cruz

A pod of humpback whales, about two or three families, adults with a few calves, have been dazzling whale-watchers since about October 18, as they feed in Monterey Bay about a quarter of a mile from Santa Cruz Harbor. Calm waters, warm weather, and an abundance of sardines, anchovies, and other baitfish have produced the ideal whale visit.

“It’s an exceptional occurrence,” says Alan Baldridge, a retired American Cetacean Society officer who lives on the bay south of Santa Cruz. Whales are common in Monterey Bay, but it is extremely rare for humpbacks, probably the most spectacular whale species to view, to be this close to land for an extended feeding session.

Cold-water upwelling (from Point Ano Neuvo to the north and the just-offshore 6,000-foot-deep Monterey Submarine Canyon) has pushed an influx of nutrients like nitrogen and phosphate compounds that feed phytoplankton, which form the base of the localized abundant food web, just offshore of the harbor.

“It’s the perfect storm,” says Dan Haifley, executive director of O’neill Sea Odyssey, a Santa Cruz-based ocean education organization.

Dolphins, sea lions, pelicans, and sea gulls are part of the feeding frenzy, too. Boatloads of whale-watchers, along with kayakers and some paddle-boarders, have been experiencing the humpbacks’ characteristic vertical lunge feeding, bubble-net feeding, and breaching.

The whales, which can weigh 45 tons and span 50 feet, are feeding aggressively and filling up before heading south to tropical and subtropical waters for the winter, where they will mate and calve, before heading north again in the spring to colder higher-latitude waters. Haifley guesses that they will remain in the Santa Cruz area for another week or so.

Concerns over the proximity of kayakers and others to the whales, which are federally protected, may lead to restrictions for the rest of the event. If you plant to visit the humpbacks, keep in mind the federal Marine Mammal Protection Act and the Endangered Species Act, which require a 100 yard distance from the animals and an effort to stay out of their path.

Learn more about whale watching off Santa Cruz.

Got Quakes on the Mind?

You probably felt only three or four of them, but there have actually been 16 brief rumbles along the Hayward Fault in the last week in Berkeley. As little quakes tend to do in Earthquake Country, these have shaken the idea of the Big One loose from its usual obscurity and brought it to the front of everyone’s minds.

And for good reason. The US Geological Survey estimates that of the seven faults most likely to generate a magnitude 6.7 or larger earthquake in the Bay Area, there’s a 63 percent chance that at least one of them will break in the next 26 years. There’s a 31 percent chance that it will happen along the Hayward Fault, the greatest chance of the seven. The fault runs for 74 miles along the western base of the East Bay Hills from San Jose to San Pablo Bay.

Even though these minor quakes get everyone talking about “The Big One,” seismologist Peggy Hellweg, at the Berkeley Seismology Lab, says they’re nothing abnormal and don’t significantly lessen the strain on the Hayward Fault. In fact, so little is known about earthquake dynamics, seismologists can’t say whether little quakes like these increase or decrease the probability of an imminent big one.

So little is known about earthquake dynamics, seismologists can’t say whether little quakes like these increase or decrease the probability of an imminent big one.

Since the initial magnitude 4 quake on October 20 at 2:41 p.m., 15 smaller aftershocks rocked from epicenters within a half mile radius in Berkeley, all occurring about five miles below the surface. Four of the larger shakes, including the initial bigger one, span a line along the fault at almost equidistant points as the crow flies between People’s Park and the intersection of Claremont  and College avenues.

These clustered quakes are not uncommon in the Berkeley area, says Hellweg. Certain areas along the fault are more prone to clustered mini-quakes, possibly due to a heightened tension from slight bends in the fault.

These quakes, and the coming large one, will be the result of the tension borne from the continued northwestward movement of the Pacific tectonic plate against the North American plate. In the Bay Area, their border roughly follows the California shoreline, with the Pacific plate moving northwest at about a rate of 40 millimeters a year. The Pacific side of the Hayward Fault creeps at about 4 millimeters a year (about little more than a quarter inch), but would need to slip at least 10 millimeters a year to prevent the tensional buildup that will result in the magnitude 6.7+ monster quake. When it finally does break, land on either side of the fault is expected to displace about six feet!

The last big quake on the Hayward Fault occurred on October 21, 1868, 143 years ago (check out Bay Nature’s 2008 feature on that). The prediction for the fault’s next big quake emerges, in large part, from the fact that the last five big Hayward Fault earthquakes broke on average once every 140 years. So, it’s time to get going on your earthquake emergency plan! Get the skinny at shakeout.org. And find a good list of resources here.

If all this geology talk has you thirsting for more, be sure to read our 2006 section all about the San Andreas Fault and plate tectonics. And check out our January 2013 story on the geology of the East Bay hills!