Change is on the land, as well as in the water, for the bay area.  Vehicles crossing the Golden Gate Bridge are no longer required to stop for tolls.  And now, as of June 1^st, 2013, commercial  shipping vessels leaving and entering San Francisco Bay are required to stay in the shipping lanes for an extended distance of approximately 6 miles.  But why?

We have abundant marine life along our coastline, including many species of large whales – humpback, gray, fin, sperm, and blue.  The whales, and others, are here for the food.  Upwelling brings nutrients to the surface, small fish, and even large whales, feed on these nutrients (seaweed and plankton), bigger animals feed on them, and so on up the food web.  Because ships and whales co-occur in the same place, there have been incidences of ship strikes.  The California Academy of Sciences is part of the Marine Mammal Stranding Network and responds to these incidents.

However, we want to reduce the issue in the first place!  With that as the mission, selected organizations and persons, led by the Gulf of the Farallones and Cordell Bank National Marine Sanctuaries vessel strike working group, made several recommendations to reduce the issue of vessel strikes, with whales.  The first being extending the shipping lanes.   There are three shipping lanes – Northern, Western, and Southern.  Observational data shows that whales are feeding in these areas.  Thus, extending the lanes past some of the preferred feeding areas in our waters lessens encounters with whales and ships entering and leaving, the sometimes foggy, San Francisco Bay. Next, the team wants to collect real-time data of whale observations to enable the National Oceanic and Atmospheric Administration (NOAA) to make informed management decisions.  Along with aerial observations by the United States Coast Guard, citizen scientists, naturalists, observers, and more can collect and share real-time sightings data.  This data can then be utilized to promote dynamic management areas.  As an example, if there are a significant number of whales in the northern shipping route, traffic can be diverted to another route.

We appreciate this win for the whales.  Stay tuned as data is collected and the dynamic management area is tested for robustness and scalability.

A special thank you to the Cordell Bank National Marine Sanctuary and Gulf of the Farallones National Marine Sanctuary vessel strike and acoustic impacts working group.

Oysters, like many bivalves, are important for marine ecosystems. The organisms filter water through their feathered gills, removing impurities as they inhale and exhale. In fact, native and invasive bivalves might filter the entire volume of the San Francisco Bay every 3-4 days!

However, oysters around the world are threatened by ocean acidification. The acidity breaks down the calcium carbonate shells of the oysters, as we reported in a video several months ago.

Recently, researchers discovered other effects of acidification on oysters and what the breakdown of the oysters’ calcium carbonate shells could mean for the acidic balance. Science Today sat down with the Academy’s own oyster expert, Dr. Peter Roopnarine, curator and chair of Invertebrate Zoology and Geology, to get some perspective on these recent studies.

In the first study, published earlier this month, scientists reported that acidification has negative effects for oysters in the larval stage. The acidity in the water makes the larvae expend much more energy than in neutral waters to make their shells.

“As the oyster larvae struggle early on and expend that embryonic energy,” Roopnarine says, “they have difficulty cranking up their own feeding.”

According to the paper’s lead author, George Waldbusser, “It becomes a death race of sorts. Can the oyster build its shell quickly enough to allow its feeding mechanisms to develop before it runs out of energy from the egg? They must build their first shell quickly on a limited amount of energy—and along with the shell comes the organ to capture external food more effectively.”

Last month, headlines reported that “Oyster Shells are an Antacid to the Oceans,” based on a study of oyster reefs in Chesapeake Bay. Roopnarine explains how oyster reefs are built over time, “Oysters do best on hard ground. The first oysters in a soft bottom environment eventually become the hard substrate that future oysters build upon. As the reef grows, the presence of the shells promotes a healthy, low acidic environment.” Or as the study’s introduction states, “Active and dense populations of filter-feeding bivalves couple production of organic-rich waste with precipitation of calcium carbonate minerals, creating conditions favorable for alkalinity regeneration.”

On a micro-scale, like the Chesapeake Bay, Roopnarine agrees that this could work. Restoration of oyster reefs could contribute to the reduction of ocean acidification problems. On a macro-scale, over geological time and large ocean mass, however, it seems that these oyster reefs could do little to undo the large amounts of CO₂ humans have been pumping into air (that’s absorbed by the oceans) for over a hundred years.

I asked Roopnarine about the San Francisco Bay’s oyster population. We had native oysters before overharvesting, pollution and sedimentation from gold mining in the Sierras buried the oyster reefs, Roopnarine says. A few are still found around the bay, but their numbers are small.

The oysters farmed locally are Japanese oysters, which, until a few years ago, were only found in hatcheries. Wild populations are now establishing themselves in the bay, Roopnarine says, which could be due to warmer temperatures. He and colleagues wrote a study a few years ago that looks at the Japanese oyster population locally.

With the important work these marine organisms do, it’s important we learn more about them to restore oyster reefs.

A former Academy staff-member, Jill Bible, is doing just this near Bodega Bay. To learn more watch this great video by the UC Communications team.

Image: Oysters showing the effects of ocean acidification, OSU

“It looked too perfect to be a rock,” he told the Associated Press.

This is a great example of citizen science, says the Academy’s Peter Roopnarine, curator of Invertebrate Zoology and Geology.

Initial dating by the Transbay’s paleontology consultant put the fossil’s age at around 11,000 years old. The huge tooth—“about a foot in length and 8 inches tall,” according to The Bay Citizen—will be donated to the Academy.

The Academy has other mammoth teeth in its collection, including three specimens found in San Francisco. Other collections from that time period in California include a saber-tooth cat skeleton, bison and dire wolves.

Peter says if we’re able to put the recent find on display, it will be a great opportunity to tell the story of the recent fossil history of San Francisco.

The late Ice Age in California had a rich diversity of mammals—large saber-tooth cats, horses, wolves, bison and of course, mastadons and mammoths. Peter explains that the area was a series of lush valleys with open plains. The nearby ocean provided a very moderate climate—making this region a cooler version of today’s African savannah.

Peter says that it’s always difficult to reconstruct the past in modern, metropolitan areas, where fossils are moved or buried without a second thought. That’s what makes Brandon Valasik’s discovery such a treasure. And the fact that Valasik himself recognized it.

We’re not sure when we will receive the tooth here, but when it does arrive, our scientists will examine the specimen for more clues to the species and age. Stay tuned!

Until last week, I had no idea what a murmuration was. Did you? Then this amazing video went viral. The science behind starlings flying in unison is stunning and more about physics than biology, says Wired.

Each starling in a flock is connected to every other. When a flock turns in unison, it’s a phase transition.

How does a hummingbird stay dry in the rain? Ask your dog. UC Berkeley researchers, using high-speed video, found that hummingbirds shake off water like dogs do, only in mid-flight, “reaching a G-Force of 34,” according to NPR. Dang!

How can two birds sing a duet so synchronous that it sounds like only one bird singing? Researchers studied Andean wrens’ neurons to understand this phenomenon. They discovered that a pair of male and female wrens memorizes the entire song, coming in when only needed. The female appears to take the lead, so perhaps “the duets are a way for a female to challenge and test a male,” ponders ScienceNOW. You can take a listen here.

Recent studies have shown that many animals are getting smaller as the climate warms. But research conducted by our friends at SF State and PRBO finds the opposite is true with Californian birds. Analyzing data from thousands of local birds caught and released each year over the past 40 years, the scientists discovered that the birds’ wings have grown longer and the birds are increasing in mass.

Extinct birds were the subjects of two separate multimedia articles last week. Cornell University, via the New York Times, has video (the only known video or image) of the imperial woodpecker, extinct since the mid-20^th century. These were beautiful birds, done in by logging in Mexico’s Sierra Madre. Listen to the audio, too. New Scientist has a gallery of “bird ghosts,” that includes drawings by Ralph Steadman and haunting music, too.

Want more? How about rewarding designers and builders for creating bird-friendly buildings? Or robins pleading guilty in spreading the West Nile virus?

Finally, have you read the ongoing “Scientist at Work” blog by the Academy’s own Jack Dumbacher in the New York Times over the past two months? Jack is researching birds in the islands of Papua New Guinea. We’ll feature a video of his work next month, so stay tuned!

Image: User:Mdf/Wikipedia