Natural Perspectives:

Last week the Amigos de Bolsa Chica hosted the second annual Bolsa Chica Science Symposium. The event was at the Huntington Beach Central Library and featured researchers who have monitored the Bolsa Chica since the opening of the new tidal inlet three years ago.

David Carlberg, Amigos president and a retired microbiology professor, gave the audience a warm welcome. Vic was the moderator.

The first speaker was Bob Hoffman, a biologist with the National Marine Fisheries Service. He began with a summary of the restoration process. Hoffman may be more familiar with Bolsa Chica than anyone now involved. He has been working on Bolsa Chica issues since 1976. He got a big laugh with a photo of himself from that year, looking like he had just come back from Woodstock.

Hoffman focused on the very high cost of sand dredging projects, like those recently at Bolsa Chica and still ongoing at Upper Newport Bay. These are expensive projects. To make them more affordable, he is encouraging development of a master dredging program that would encompass all the coastal wetlands of Southern California. The only sacrifice would be in the management independence of each of these wetland sites.

At Bolsa Chica, the $147-million restoration project created the magnificent new full tidal basin, and left an endowment for ongoing maintenance and monitoring. Unfortunately, the cost of dredging has increased while the interest earned on the endowment has collapsed.

Because sand naturally moves south along the beach, lagoons and embayments gradually fill with sand. One with a stream flowing into it will naturally cleanse during storm flood events. However, to maintain a higher water quality, no storm drains or flood control channels empty into the full tidal basin at Bolsa Chica. This means that it will naturally fill with sand over time, and will need to be dredged periodically to maintain the deep water habitat.

The first dredging, which was an expected expense, cost $3 million, which was more than anticipated. And worse, shoaling rates — the extent of sand accumulation over time — are higher than expected, which means that dredging will need to be done more frequently than was originally anticipated. Because of the low interest being earned on the endowment, capital had to be used to pay for the dredging.

Only $12 million is left in the endowment fund, which has to pay for staffing, monitoring and maintenance of the Bolsa Chica full tidal basin. Regrettably, there are no big grants available for maintenance of wetlands, only restoration. Hoffman concluded that changes must be made in how coastal systems are managed and in how coastal wetland maintenance is funded.

Rachel Woodfield of Merkel and Associates presented updates on the biological monitoring. She summarized an enormous amount of data that Merkel employees (under contract to California) have accumulated on the various bird and fish species at Bolsa.

A bird species almost never seen before at Bolsa Chica was present this past summer, but it was not a cause of celebration. The gull-billed tern is a predator that will eat the chicks of other birds. Unfortunately, the gull-billed terns that showed up at Bolsa developed a taste for chicks of western snowy plover, a threatened species. But management came up with a clever response — putting metal cages over the nests. The chicks could wander freely in and out of the open wire mesh, but the predators couldn’t get to them. This should improve nesting success next season.

In our opinion, Woodfield’s most important news was that the population of Savannah sparrows is doing well. Habitat for this endangered species was actually reduced, temporarily, by the construction activity of the restoration project. Many people have had their fingers tightly crossed for the past few years, waiting to see if the sparrows would thrive under the new restoration project.

Fortunately, the restoration plan has proven successful. Before restoration, the average population at Bolsa Chica from 1986 to 1994 was 143 pairs. After restoration, Savannah sparrow numbers were 361 pairs in 2007, 193 pairs in 2008, and 269 pairs this past summer. The sparrow’s pickleweed habitat is recovering and so is the sparrow. That’s a great relief.

Fish also are thriving in the full tidal basin. Monitoring with beach seines and otter trawls turned up 46 species of fish that are using the new bay. Topsmelt and grunion are the most abundant, with many California killifish, anchovies and gobies as well. Juveniles of all species were found, indicating that the bay is serving its important function as a fish nursery.

Monitoring of the bay bottom turned up the usual suspects — crabs, shrimp, octopus, worms, nudibranchs, clams and other mollusks. These bottom dwellers are important components of the food chain.

The eelgrass transplant project in 2007 was a great success. Volunteers from the Amigos de Bolsa Chica, Bolsa Chica Conservancy and Orange County Conservation Corps helped harvest, sort and plant this marine plant, installing about .9 acres of eelgrass in clumps. Those initial patches have filled in to cover a whopping 32 acres in just two years.

Cordgrass was also transplanted in 2007. It grows more slowly, and still only covers a couple of acres, which is just under double the initial acreage. Studies from other projects showed that growth of transplanted cordgrass really takes off at five years, so we can expect better abundance in 2011. Adequate stands of cordgrass are necessary for light-footed clapper rails, which do not currently breed at Bolsa Chica.

Other exciting findings came out of this conference, including a new world record that may be set soon at Bolsa Chica, but we’re out of space. You’ll have to wait until next week to hear about those results.

VIC LEIPZIG and LOU MURRAY are Huntington Beach residents and environmentalists. They can be reached at vicleipzig@aol.com .