Category: Science

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Road Blog: Mendocino Vineyard

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Back home in Berkeley tonight. But at noontime today, we stopped on our way south at Toulouse, a vineyard and winery along Highway 128 in Mendocino County. We went into the tasting room and bought some wine, then walked up through the vineyards briefly. One bird note: We see robins down here, of course. They’re everywhere, right? But up at Toulouse today, their presence was a little more than we see around the city. hundreds if not thousands of robins filled trees around the harvested vineyards. Checking one Mendocino birding site, the county seems to be a major wintering locale for American robins (Turdus migratorius; yes, “Turdus”; it’s Latin for “thrush”; you know there’s a whole story about why it’s called “robin,” but some of us can’t stay up all night to tell it).

A general explanation for the robin swarm around the vineyards comes from Cornell’s Birds of North America: “The diet of the robin is … highly variable, changing from primarily soft invertebrates, especially earthworms, in spring and summer, to primarily fruit in autumn and winter. During the nonbreeding season, large flocks of hundreds or thousands of immature and adult birds migrate to lower elevations and latitudes, where they form roosting aggregations from which they track sources of berries.” Cornell also notes that the robin is a relatively recent arrival in much of California west of the Sierra foothills, not pushing into other parts of the state until irrigation and well-watered lawns (and thus a richer supply of earthworms near the surface) made it possible for the bird to extend its range. And one more note from that Mendocino County site: robins (and some other abundant songbirds) are favored prey of some raptors (peregrine falcons and sharp-shinned hawks, among others).

The sound of the birds near the vineyard was remarkable enough I recorded some audio and will try to post that later.

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It’s December. Do You Know Where Your Rain Is?

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It’s December now in the Bay Area, and if you’re fastidious about your weather expectations, you look out the window and want to see rain. Or at least a little gray. But in the wake of the little wind event of the past couple of days, what I see out there is a sparkling azure sky without a hint of a cloud.

Our climate is mostly dry from sometime in April to sometime in October, mostly wet from October to April, except when it’s not. And when it’s not, we’ve got trouble. Yes, things in the cities are beautiful, and when you turn on the spigot, water from somewhere magically appears. But you know that somewhere–up in the Sierra, out in the Valley–things aren’t so good. There won’t be enough mountain snow to help replenish the reservoirs in the spring. The farmers will want water they cannot get. The fish and wildlife that depend on an abundant flow of water through the Delta, species threatened because for decades they were last in line when people thought about how to spend the water we bank, will suffer. The edge to the anxiety comes from the knowledge that drought happens here, and drought can become a social and political as well as a natural and environmental mess.

Feeling nervous yet? I am. I follow Jan Null, a Bay Area meteorologist. Here’s his climate summary for last month:

November 2011 was a cool and mostly dry month across California. Monthly average maxima anomalies were -1.0 (San Jose) to -3.6 degrees (Los Angeles), while monthly mean anomalies were -0.8 to -2.3 degrees. North of the Tehachapis rainfall was well below normal ranging from 28% of normal (Sacramento) to 69% (Eureka) while Southern California was quite wet with Los Angeles and San Diego at 152% and 309% of normal respectively.

Sometimes, to reassure myself that all will soon be well, I might take a spin through weather and climate sites to see what the professionals are saying about the forecast. That image to the right is a graphic of the Quantitative Precipitation Forecast from the California Nevada River Forecast Center. During a wet period, the map will be a glorious swirl of color–blue and green and yellow, depicting progressively heavier precipitation, and sometimes orange and splashes of red and magenta when it’s really wet (there’s a scale at the top of the map; click on the image for a full-size version). Gray, on the other hand, means dry. No rain in the lowlands. No snow in the uplands. No reassurance.

Next, here’s how one of the meteorologists down in the Bay Area National Weather Service office in Monterey sums up the coming week in the Area Forecast Discussion (using familiar all-caps weather advisory style):

DRY WEATHER LOOKS TO BE IN STORE FOR THE DISTRICT SUNDAY THOUGH NEXT WEEK. HOWEVER…THE MODELS ARE STARTING TO SHOW SOME DIFFERENCES. THE ECMWF KEEPS A STRONG RIDGE ALONG 135W STRETCHING INTO THE GULF OF ALASKA WITH A STRONG SHORTWAVE DIVING DOWN THROUGH THE GREAT BASIN LATE THURSDAY INTO FRIDAY. THIS SCENARIO WOULD BRING ANOTHER BOUT OF GUSTY OFFSHORE WINDS. THE GFS WEAKENS AND FLATTENS THE RIDGE BY THE END OF NEXT WEEK…WITH A SHORTWAVE MOVING INTO THE NORTHERN PLAINS NOT DIVING SHARPLY SOUTHEAST. THIS WOULD NOT BE A WINDY SCENARIO FOR THE DISTRICT. REGARDLESS OF THE MODEL…DRY WEATHER IS IN STORE THROUGH THE END OF THE NEXT WORKWEEK.

Got that? The major question the weather persons are dealing with is whether or not the forecast models indicate another windstorm for the coming week. Chances of rain–none apparent.

The pluviophile now turns eyes to the coming month, even though we’re exiting the realm of forecasting and prediction and entering into one of probabilities and outlooks. But here goes: The National Weather Service Climate Prediction Center says the Bay Area should have “near median” precipitation in the period from eight to 14 days from now (median in this case meaning rainfall along the lines of the “middle 10 years” of the past three decades in terms of rainfall); the northern quarter of California is looking at below-median rainfall during that period. The center’s one-month outlook shows equal chances of above, below, or near median precipitation. That’s because “there were no strong and consistent climate signals” among the forecast models.

And one last stop: Both the most recent U.S. Drought Monitor report and the seasonal outlook, through the end of February, show California drought-free (things look scary in Texas, though).

So where’s the rain? Like that TV show used to say: Out there. Somewhere.

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Back-Porch Visitor: The Meal

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As reported earlier, recent human activity at our address discommoded a spider that has taken up temporary quarters on our back porch. Its web was trashed.

Less than 24 hours later, the spider had spun a new web and was ready for business. In fact, just a few hours after we spotted the new web, our outdoor housemate had secured its first meal–apparently a honey bee. Kate mentioned this morning that these (and other) spiders weave patterns into their webs with silk that are highly reflective of ultraviolet light; the patterns mimic ultraviolet reflections from flowers. The theory, reported in 1990, is that the patterns trick prey, which expect a nice cool sip of nectar, into entering the web, whose proprietor has a different notion of refreshment.

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A Falcon’s Journey

islandgirl.jpg Thanks to Marie, who posted the link:

The online diversion of the day is the Falcon Research Group, an independent raptor study center in Washington state. The group has satellite-tagged and tracked peregrine falcons that migrate over very long distances. Right now, they’re watching a falcon they’ve named Island Girl, who is in the midst of a journey from Baffin Island, northeast of Hudson Bay, to southern Chile (here’s the map of the migration so far). She left Baffin Island on September 20 and last night apparently crossed Louisiana’s Gulf Coast. If she was a straight-line flyer, and she’s not, she would have covered 2,600 miles in 11 days. One of her stops this past week was apparently atop the Illinois State Capitol in Springfield.

The research group blogs the migration here: Southern Cross Peregine Project. The account of the bird’s journey, informed by both experience with her life history, peregrine biology, and GPS data from a mini-backpack the bird is carrying, is both fascinating and sort of gripping. For instance: This is the third season the project has tracked the bird south. One post notes she has begun the migration inside a 24-hour window on September 20-21 each time (her northward migrations are similarly precise, occurring around April 12). Of the challenges peregrines face as they cover a vast swath of territory, the blog says:

Peregrines (and other long distance migrant hawks) can make a living catching their prey over a wide range of habitats. They must be able to do so if they are migrationg across such varied territory as the Arctic tundra, the Canadian boreal forest, the farmlands of the Mid-West, cities large and small, the sub-tropical regions of Mexico, the tropics of Central and South America, the intense Atacama Desert and the pine forests of southern Chile.

They must be adaptable enough to survive in each of these situations. They must have a flexible approach to hunting in different situations. They must be able to recognize, hunt and catch new prey species (do peregrines eat toucans?) and avoid all of the ever-present mortality sources.

Are these “slow migrant” peregrines that we have discovered during this study taking their time so that they can become familiar with these habitats and how to hunt them? Are they “familiarizing” themselves with their migratory route and what they can find there? Is this advantageous to them?

The complexity of peregrine migratory behavior is both deeply impressive and humbling. What a remarkable organism to fit into all of this and flourish.

Where’s Island Girl now? When last heard from, she was headed out over the Gulf of Mexico southwest of New Orleans. As the blog notes, the falcon may “attempt to fly across the entire Gulf of Mexico. It has been done by other satellite tagged peregrines in the past. However, taking this route means committing to the very exposed crossing of 500 miles across open water to Yucatan. Some tagged raptors have disappeared on this crossing. … If Island Girl does go and if she has a good tail wind, she is capable of making it. Keep in mind that there are also a lot of oil platforms out there to rest on and we know that peregrines show up on them during the fall migration fairly frequently. There are also lots of ships in the Gulf so she may have assistance there if she gets into trouble with a headwind.”

Six thousand miles to home. Go, bird, go.

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Boreal Chauvinist Welcomes Fall

The autumnal equinox–I’m letting my boreal chauvinism show–is just an hour or so away (2:05 a.m. PDT, 0905 Coordinated Universal Time. Special treat if you’re up in these wee hours: a crescent moon rising (nearly) alongside Mars).

In other equinox news, an explanation of the equinox by way of a 2007 NASA Astronomy Picture of the Day.

And not strictly equinox-related, but too beautiful to pass by: NASA’s Astronomy Picture of the Day for today, which features the aurora borealis as viewed in northwestern Canada. If you like that image, there a lot more here.

Update: Well, the sun is up and it’s sure enough fall. I was looking for an apt seasonal quote, and this morning Kate pointed one out; something from John Muir, cited as an introductory quote in a book of Diane Ackerman essays, “Dawn Light”:

“This grand show is eternal. It is always sunrise somewhere; the dew is never all dried at once; a shower is forever falling; vapor is ever rising. Eternal sunrise, eternal sunset, eternal dawn and gloaming, on sea and continents and islands, each in its turn, as the round earth rolls.”

(The quote apparently comes from Muir’s journals, published as “John of the Mountains” in 1938.)

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Vanishing Moon

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It’s been cloudy most of the day here, creating some minor suspense about whether tonight’s eclipse will be visible.

Well, at least the start of it is–despite appearances, the shot above is through some high clouds. No telling when the thicker cloud cover will return. The shot immediately below: a few minutes later, as the clouds got a little thicker. And the last, about an hour after the first, and just a few minutes before the eclipse was supposed to enter it’s “total” stage. Thing is–down here in the Berkeley flatlands, anyway, that’s when the clouds really moved in. I have to be up early, so no late-night moongazing to see if it re-emerges.

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Salmon Walk: Devil’s Gulch Creek

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Word was out toward the end of last week that coho salmon had appeared in Lagunitas Creek and tributaries in western Marin County, to the north and west of us here in Berkeley. Coho are endangered on our part of the coast, so their annual appearance is an occasion; and also a rarity, because Lagunitas Creek has one of the few viable wild population on the north-central California coast. I had heard that the fish–were talking about five dozen fish so far–were spawning both in the main creek and in a couple of tributaries: San Geronimo Creek and Devil’s Gulch Creek. San Geronimo flows into Lagunitas Creek after skirting several small West Marin townlets and passing a golf course; to get into San Geronimo Creek, the salmon (and the steelhead trout who migrate later in the season) have to make their way up a series of low falls and rapids called the Ink Wells. With few salmon returning the last couple of years, very few have made it up there, but this year maybe 30 fish have gotten past the barrier and started to spawn.

Devil’s Gulch Creek was an unknown to me and appeared on maps to be a tiny little thing. Frankly, it’s hard to imagine big fish going some of the places these big fish want to go. I was told a few days ago by a watershed biologist that salmon were spawning in Devil’s Gulch, though, so I went this afternoon to check it out (yes–the sad truth is that for all my interest in California salmon, I’ve never seen truly wild fish spawning).

I didn’t see any today, either. But I can confirm the creek is small, rocky, and full of the things that biologists say the coho need: gravel beds (for spawning) large woody debris (to provide refuge for growing salmon in the year-plus they’ll spend in the stream before migrating to the ocean), and lots of shade (to keep the water cool–salmon don’t tolerate warm water). Next time I’ll try to give myself more than the tail end of daylight to conduct my explorations (it was pretty much dark when I got back to the car).

(Picture above: Devil’s Gulch creek, just upstream from the Sir Francis Drake Boulevard bridge–you can see the road in the background. Here’s a Flickr Devil’s Gulch slideshow.).

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Filling in the Map

Sunday was spent noodling with HTML in the morning, then in the afternoon getting in the Tiny Car (the Chicago-bred Toyota Echo) and driving from Berkeley out to Antioch, up the Sacramento River to the Delta Cross Channel, then east to where our local utility district stores our water as it flows out of the Sierra Nevada. The destination was chosen because the East Bay Municipal Utility District runs a fish hatchery on the Mokelumne River, and I wanted to see that. The route was dictated because the Delta Cross Channel is the route by which much of the water exported from Northern California down to the San Joaquin Valley and Southern California is diverted from the Sacramento. I’ve driven past and ridden my bike by the Cross Channel gates dozens of times, but, not knowing what the heck they were, I never took note of them. Anyway, the drive was part of a long-term project I think of as filling in my map–touring what is largely terra incognita and figuring out how the pieces relate to each other.

It was a beautiful day, anyway, even with no end in mind. I saw water. I saw levees. I met a lonely bridgetender and photographed him and his antique bridge. I encountered a dead skunk and a curious ostrich. And then when I got out to the hatchery, I was hours too late — it had closed at 3 p.m.

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Today’s Top Exotic, Invasive Aquatic Menace

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In case you need a break from worrying abut what Al Qaida is going to do you or the horrors you’ll suffer at the hands of Obama-care,or the devastation in store if the Tea Party takes over, here’s another terror to contemplate: the New Zealand mudsnail. Somehow, this critter has not been on my radar. But my ignorance was altered yesterday during a visit to a fish hatchery on the Mokelumne River (that’s pronounced mo-KULL-uh-me, if you’re wondering). It was a short visit as I arrived a good two and a half hours after the place was closed for the day. But this sign was on one of the gates.

The numbers are eye-catching: the snail could occur in densities of 1 million per square yard (that’s 110,000 per square foot), and the snail propagates so rapidly that a single snail could give rise to 40 million within a year. The damage it does: It can outcompete native species and rip apart the food web that even large fish species depend on. In fact, the Mokelumne below this point is a place that has been invaded and studied as part of conferences on the mudsnail. And in recent mudsnail news, the city of Boulder, Colorado, recently closed a park because of the discovery of New Zealand mudsnails in a local creek. A short history from the state of Colorado says that the snail first invaded streams in the northern Rockies and that Yellowstone was one of the first places infested. And here’s everything else you need to know about the critter, thanks to the U.S. Department of Agriculture: New Zealand mud snail (Potamopyrgus antipodarum).
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California Salmon: Oroville Hatchery

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I read a press release from the state Department of Fish and Game last week that the hatchery up in Oroville, on the Feather River just below the big State Water Project dam, was about to open its gates to fall run chinook salmon and steelhead. Saturday we drove up there, 142 miles from Berkeley, to see what the show looked like. After several years of disappearing fall salmon runs, it was a thrill to see the fish coming up the ladder toward the hatchery. In the river at the bottom of the fishway–a low dam blocks the fish from going any further upstream–it seemed there were hundreds of salmon, maybe more, churning the water and leaping into the air. The ladder includes a below-grade viewing area so you can see the fish on their way up. We were there for two or three hours, and we saw a steady stream of people, including lots of families with kids, coming to check on the run. Very cool.

Still reporting the story, but watching the fish, one is seized with the feeling where there’s life, there’s hope for the salmon. (And yes, that feeling persists even knowing to what a huge degree humans are intervening in the process we’re watching. A hatchery is really a kind of fish factory after all, though that’s not entirely visible when you’re watching the salmon progressing up the ladder. I’ve had a couple people ask me, “After they come up to the hatchery, what happens?” Well, technicians step in and harvest the roe and sperm from the fish and kill them in the process. For salmon, that’s the same end result as the wild run–though vastly different in the details and perhaps the quality of fish that result. For now, in this place, the hatchery is all we have left to keep the run going. So a celebration is in order despite our heavy-handed intervention.)