Tarantulas on Mt. Diablo

TARANTULAS (September 95)

by Michael Ellis

I witnessed a most remarkable sight last Sunday on the slopes of Mt. Diablo — the mass movement of tarantulas. I must have seen 25 of these giant arachnids walking around and I escorted a number of them safely across the road. Every fall the males leave the protection of their burrows and search for females. I had always heard of this phenomenon occurring in the inner coast ranges, in Southern California and in desert regions but I had never actually seen it. In fact until last weekend I had only seen tarantulas in South America. These spiders are big; I was impressed.

Technically the California spiders are not true tarantulas. The original Lycosa tarantula is found only in Europe and is a member of the wolf spider group. Tarantulas take their name from the small Italian town of Taranto, where they were once numerous. Here the people believed that the bite of the tarantula was fatal. Just preceding death the victim entered a state of melancholy called tarantism. In order to survive death you had to listen to music during this tarantism. Not just any music, but the right music, which varied according to the particular whims of the victim.

The doctor would lead the patient, who was dressed in flowing robes, into a room where an orchestra was assembled. The doctor would then take the musicians through a few numbers. The patient would be unmoved until the right tune was struck. With a wild look in the eye, he’d get up and begin an uncontrolled frenzy, leaping about, flailing his arms and shrieking (I have seen similar behavior at a Grateful Dead concert). Finally dripping with sweat he’d drop, totally exhausted, but completely cured. I can just imagine the scene at the emergency room at Kaiser….” I just got bit by a spider. Is the orchestra in and do they know anything by The Moody Blues?”

The patient would have recovered anyway. Tarantula bites are not fatal; in fact it’s pretty hard to get one to bite you. But it was probably a good opportunity to act out some fantasies.

There are 15 or so species of “tarantulas” in California, which belong to a family called the Mygalomorphs. These are considered relatively primitive spiders because they do not spin webs, their mouthparts operate in a vertical fashion and they have four lungs. More advanced spider groups spin webs, have mouthparts that pinch and have two lungs.

All the tarantulas I saw were males. They are easily identified by the presence of giant pedipalps. These are large leg-like appendages near the mouth. In the fall a male constructs a sperm web where he deposits some seminal fluid. He then takes up a little of that sperm into special reservoirs on the tips of his pedipalps. Now he is ready to roll. Normally these spiders are nocturnal but during the breeding season the males are out night and day cruising for females.

When he finds a female burrow he taps the entrance with his legs and entices her to emerge. This is a dangerous operation. Tarantulas have been known to kill and eat animals much larger than themselves including small rodents, lizards, a small rattlesnake and even other tarantulas. The female may charge him with her fangs exposed. He grabs her fangs with special spurs on the inside of his front legs. He then flips her on her back and rhythmically uses his pedipalps to brush past her sternum. (Are you beginning to breathe hard here?). He places his packet of sperm in her genital pore and makes a hasty retreat; he doesn’t want to get eaten. In humans mating occasionally follows dinner, in spiders dinner occasionally follows mating.

The male tarantula will soon die; his job is done. Females on the other hand have been known to live over 20 years! Soon she will plug her burrow and spend the winter safe and secure far underground. Deep in her lair the following spring she will spin a thick egg sac and deposit 500 to 1000 eggs in it. The spiderlings hatch in about a month; the mother tears a small hole in the sac for her babies to emerge. They hang out with her for awhile before leaving the burrow. And the cycle for another amazing animal begins anew.

The History of the Farallon Islands

Farallons

The native Americans called them the Islands of the Dead and never set foot on them, at least not earthly feet. The first European to see them was the Portuguese explorer, Cabrillo, employed by Spain sailing off the coast in 1542. But the first human to actually walk on the island was Francis Drake. After spending five weeks on the Point Reyes peninsula during the summer of 1579 repairing his damaged ship, Drake sailed west. He stopped at the largest island to gather seabird eggs and to salt sea lion meat for the voyage into the unknown. Drake named the tiny archipelago, the Islands of St. James. The name didn’t stick. It is difficult to imagine the local fishermen catching rockfish off the “Islands of St. James.” That name seems too refined for the stark and windswept isles.

In 1769 the explorer Juan Francisco de Bodega named the islands Los Farallones de los Friales, the rocky islets of the Brothers. That moniker stuck. “Friales” honors the Fransican monks who were busy subduing and baptizing the native “heathens” of California.

There are actually three islands or -more properly – three groups of mountain peaks jutting above the surface of the sea. The South Farallon group is the largest and best known. Located 26 miles southwest of the Golden Gate Bridge, it consists of about 120 acres and is the only island capable of marginally supporting humans. The Middle Farallon, 3 miles northwest, is nothing more than a large rock. It is colloquially known as the Pimple, a disgusting but appropriate term for a guano-covered rock. Four miles northwest from the Pimple is the North Farallon group. It is an inaccessible assemblage of seven steep and rugged peaks.

The wildlife on the islands suffered only minor depredations from passing seafarers until the arrival of the O’Kain. This New England vessel and four other sealing boats landed at the Farallons on August 1810 and for the next 22 months the crew slaughtered northern fur seals. It is estimated that 150,000 seal pelts from the Farallons were sold in China for $2.50 a piece. Most of the animals that were disturbed and exploited have returned to repopulate the Farallons but the northern fur seals never recovered from this intense carnage and are still absent from the area. Isn’t capitalism great?

Soon after the O’Kain left the Russians arrived. They had been hunting the northern fur seal and sea otter on the breeding grounds in Alaska and followed the animals south into California. Winters in Russia can be very cold and there was a large market for the warm pelts of these marine mammals. Ft. Ross was the center of Russian occupation but there were outposts in Bodega Bay and on Angel Island. Aleut and Pomo Indian slaves did much of the work for the Russians. They regularly kayaked out to the Farallon Islands to seasonal camps to gather bird down, eggs, sea lions, and fur seals. The Russians sold out in 1841 and went home. Big mistake for them.

The Farallons were given a slight reprieve, very slight, until the discovery of gold precipitated an invasion of California. Soon there were many people in San Francisco with a burning desire for eggs at breakfast. Petaluma was yet to become the chicken capital of the West. And when there’s a need, there’s an entrepreneur.

Doc Robinson came west to start a theatre company but soon discovered more money was to be made by stealing. He plundered eggs from the common murres nesting at the Farallons and sold them for $1.75 a dozen. The Farallon Egg Company was soon formed and every May through July ten to fifteen men gathered, packaged, shipped and sold the eggs. During the early days 600,000 eggs were taken per year; an estimated 14 million eggs were removed in a 40-year period. The original murre population of a half million was reduced to several thousand by the turn of the century.

The infamous Farallon Egg war (surely every California child knows this story) was fought on June 6, 1863. Bat Shelter and his gang of 25 armed men attempted to invade the Southeast Island and depose the Farallon Egg Company. After a 20 minute gun battle five men lay wounded and one dead. Bat was driven off. Shoot-out at the OK Egg Ranch? It almost has that Louis L’Amour flavor.

As the port of San Francisco became busier, ships off the fog- shrouded coast kept running into the Farallons. So construction began on a lighthouse at the top of the 317-foot island in 1852. The light was lit on January 1, 1856, the third lighthouse along the Pacific coast.

With the arrival of the four keepers came the necessary human accouterments: wives, children, rabbits, mules, cats, turkeys, goats, chickens, and house mice. Rabbits nested in auklet burrows, cats ate baby birds, children drove the seals and sea lions off the breeding rocks, and wives hung laundry in gull colonies. An island occupied solely by seabirds and marine mammals for 10,000 years was severely disrupted in a decade.

In 1880 when a fog signal was being installed on the island, a fistfight broke out between the keepers and the eggers. The eggers feared the seabirds would stop laying due to the noise. The birds kept laying, but this was the last straw for the Lighthouse Service. The U.S. army arrived and permanently evicted the Egg Company. The keepers then took over the profitable business and golden egging continued until 1905.

One of the birds that the eggers avoided was the tufted puffin; it could bite a finger to the bone. However beginning in the twentieth century a more pervasive evil – the internal combustion engine – threatened. Ships routinely pumped their bilges out by the Farallons before entering San Francisco Bay. Tufted puffins and other birds that had survived egging began washing up on the Farallons –oiled and dead.

There was some awareness of the biological importance of the Islands. John Kinder, lighthouse keeper from 1917-1927, was a charter member of the Golden Gate Audubon Society. Teddy Roosevelt declared the North and Middle Farallon a wildlife refuge in 1906. But it wasn’t until 1969 when the South Farallon was declared a National Wildlife Refuge that the prospects brightened for the animals.

Another crucial event was automation of the lighthouse in 1972. This ended 117 years of continuous occupation by the community of lighthouse keepers. Currently the Coast Guard only visits periodically to conduct routine maintenance on the light.

Since 1970 the Point Reyes Bird Observatory (www.prbo.org) has acted as caretaker of the Farallon Islands. The PRBO not only protects the islands from unauthorized visitors, but directs important biological research as well.

Many of the seabirds and marine mammals have either returned to the Farallons or greatly increased their population in recent years. Elephant seals, absent for over 100 years, have begun breeding again, over 400 were born last year. The twelve species of seabirds that nest on the island contain over 250,000 members. This is the largest seabird rookery in the U.S. outside of Alaska.

The Farallons are within the boundary of the Gulf of the Farallones National Marine Sanctuary. This act signed into law in 1981 affords additional protection. But 50,000 barrels of low-level radioactive wastes dumped near the Farallons for twenty years by the US government are leaking. As ship traffic increases into the SF Bay it also increases the chances for a catastrophic oil spill. We are watching.

My dear friend Peter White has written the definitive book – The Farallon Islands, Sentinels of the Golden Gate. Scottwall Associates, San Francisco. 1995.

Sex? Why?

Ah spring! The season when a young man’s (and woman’s) fancy turns to love. What a noble sentiment. However in reality this is a season of intense competition and reproduction fervor. Wilson warblers sing from every willow thicket, red-winged blackbirds dive-bomb ravens, male mule deer are becoming horny (antlery?), newborn fawns frolic in the mustard, teenagers skip school and go skinny dipping, purple-spotted shore crabs burst with eggs, and wildflower pollen drifts in the wind. The entire world seems involved in duplicating itself.

An organism can accomplish this duplication by either reproducing asexually or sexually. Asexual reproduction is easy; it does not require a partner. An amoeba for example simply divides into two parts. Strawberries leapfrog into new territory with baby plants called runners. A female aphid eating a rose bush doesn’t need a male; she lays unfertilized eggs that hatch into other females. The resulting offspring of all these organisms are genetically identical to the parent and are called clones.

Aren’t you glad your kids can’t clone? Imagine if they went into their room and then split in two. “Dad! Set another plate for dinner.” But humans only propagate sexually.

The sexual method of reproduction isn’t new or confined to the “higher” forms of life. About 570 million years ago, primitive multicellular organisms evolved some specialized cells that rearranged the genetic material (chromosomes) of the organism. If these precursor cells were male, they then split into sperm; if female, then into eggs. The sperm and the eggs contain only one half of the original genetic material of the parent. When they come together during fertilization, the result is a full complement of chromosomes and a genetically unique new individual. Not a clone.

Therein lies the paradox of sex. If the biological bottom line is to pass on to the next generation as many genes as possible, then why does a strategy persist, that requires the loss of one half of the parent’s genetic material? Asexual reproduction is more efficient, less risky and quicker. It results in offspring 100 percent like the parent. Yet sexual reproduction is widespread and common; there must be some powerful advantage to it.

There are several theories to explain this dilemma. One is called the “best man” and was developed by George William in the early 1970s. For an organism that is thriving and well suited to its environment, asexual reproduction is the best choice. For example an aggregating anemone living on an intertidal rock just splits in two and forms large clonal groups. Why should it sexually reproduce and give up half of what makes it successful?

But what if the environment changes? Let’s assume the sea temperature increases. The clonal anemone group is doomed; there is no flexibility, no genetic diversity to cope with a changing world. However this particular species of anemone also reproduces sexually. By reshuffling its chromosome deck and spilling sperm and eggs into the ocean, the anemone produces offspring that are genetically variable. A few of these anemones, the “best men,” may have what it takes to survive in the higher sea temperatures. Sexual reproduction may enable this organism to flourish in a dynamic and changing environment.

Another theory proposes that disease pathogens are the motivating force behind the evolution of sex. In the primordial ooze some microorganisms became parasites of other microorganisms. The victims constantly check the “passports” of all cells and if they are invaders, destroy them. Occasionally a pathogen mimics the passport and succeeds in parasitizing the host. By sexual reproduction, the host can reshuffle the genetic deck and change the “passport.” The next generation of potential hosts is now protected from the pathogen. Sexual reproduction has again saved the day.

Confusing? You bet. We still don’t really understand why sex evolved or why it persists. But it’s definitely here to stay. Might as well enjoy the paradox..

Words for Birds

Oh ye faithful followers of Footloose Forays know that I have a strong interest in words and their derivations. No, it’s an overwhelming pre-occupation. Well, perhaps it’s more like an irrepressible passion. OK, OK I admit it; it’s an overwhelming OBSESSION. Ob (on) sedere (sit)…to sit on relentlessly. But I find that by learning the name of something it becomes less mysterious and more familiar. And by knowing how that name came to be, I not only get the history behind the word but I can remember it better.

Herein are some of my favorite bird names and their origin. For reference I use The Encyclopedia of North American Birds by John Terres and The Dictionary of American Bird Names by Ernest Choate.

But first, some background. There are numerous common names for birds; these names vary not only from country to country but even from state to state. For example there are two birds commonly called a robin. The one in England is quite different than the one in Virginia. Scientists however have created a universal system that allows only one scientific name for each organism on our planet. These names consist of two words, a Genus and a species, that are usually derived from Latin or Greek. The European Robin is Erithacus rubecula and the American Robin is Turdus migratorius (kids love that one… the migrating turd).

The American Ornithologists Union has also agreed that there is only one acceptable common name for each bird. This is possible because there are so few species of birds in the United States (only 800 or so). This would be nearly impossible with plants because there are so many (in California alone there are over 5,000 species of higher plants!) There are, of course, still colloquial names in use. Some people refer to American Goldfinches as wild canaries and House Finches as linnets. I know what they are talking about and don’t bother to correct them.

Many people get upset when they discover that a bird they know very well has been renamed. Suddenly a Marsh Hawk becomes a Northern Harrier, a Gallinule becomes a Common Moorhen, an Audubon’s Warbler becomes a Yellow-rumped Warbler. The birds, of course, could care less what humans deem to call them; they are what they are.

I have seen very polite and calm people turn into raging fiends as they rail against those awful scientists, those elitists who change names in order to confuse and perplex innocent birdwatchers. These name changes however aren’t arbitrary. The rules (we must have rules) are that the first common name used for a particular bird is the correct one. When the Europeans invaded the New World they usually assumed that they were seeing all new bird species and so of course they gave them new names. (This wasn’t the case with the Robin, however.) Many years later ornithologists determined that a Marsh Hawk in Montana and a Harrier in England are exactly the same species. And the oldest name has preference. The same thing happened for the Gallinule and the Moorhen. So don’t take it so personally.

In other birds, what were originally thought to be two separate species are, in fact, two races of one species. Even though they differ in appearance the Myrtle Warbler of the eastern United States and the Audubon Warbler of the western region were found by researchers to be exactly the same species, that is they are capable of mating with one another and producing viable offspring. Therefore it was necessary to lump the two species into one and to come up with a new name for both — the Yellow-rumped Warbler with a race of “Myrtle” and a race of “Audubon.”

The opposite also occasionally happens when two races of a single species are found to be actually two different species. In this case the species must be split into two. The light race of the Western Grebe is now known as Clark’s Grebe. The red phase of the Yellow-breasted Sapsucker is now the Red-breasted Sapsucker.

Many bird names are echoic or onomatopoeic, that is the names reflect the call or song of the particular bird. Some examples are Killdeer, Phoebe, Murre, Willet, Bobolink, Poorwill, Dickcissel, and Cuckoo. Unfortunately for us some of these birds are named for one of their close relatives (often found in Europe or the eastern United States) that makes the sound for which the whole group is named. The Black Phoebe does not fee-bee it pee-wees. Our Yellow-billed Cuckoo doesn’t cuckoo it kuk-kuk-kuks. Oh well.

Other common names describe the action of the bird — Turnstone, Oystercatcher, Woodpecker, Dipper, Flycatcher, Skimmer, Wagtail, Hummingbird, Creeper, and Swallow. While some other names are purely descriptive such as Yellowlegs, Bluebird, Longspur, Waxwing, and Redshank.

Ospreys are frequently seen in waterways throughout the Bay area. Back from the DDT-induced brink of extinction, this cosmopolitan bird is home on every continent but Antarctica. These magnificent eagles would strike terror in the minds of their prey, if only the prey was a bit more aware. Plato, whose opinion about fish closely mirrors my own, said that “fishes are senseless beings, which have received the most remote habitations as a punishment for their extreme ignorance.”

I guess another punishment is the presence of ospreys. Os is Latin for bone and fraga is from frangere, to break. Osprey literally means the bone breaker. This name originally applied to the European vulture (the Lammergeier), for its habit of dropping bones from the air to break them into pieces. Somehow
this word was incorporated into English and now applies to our fishing eagle.

The Dark-eyed Junco is a common sparrow that frequents bird feeders in the winter as well as many other habitats. However it’s common name comes from the Latin for a rush, Juncus, which this small bird was thought to prefer. It doesn’t.

Most people think that the word loon is from lunatic, as in “crazy as a loon.” These birds do in fact have a loud, eerie cry on the breeding grounds. But Loon is actually from an Old Norse word, lomr, which means clumsy oaf. Loons have legs that are located far back on their bodies, perfect for propelling themselves in water where they spend most of their time. But on land they must plop along on their bellies to move, they cannot even stand up on their legs, hence their awkward movement.

Storm petrels are oceanic birds seldom seen from land. Because they often patter across the sea, they were named for St. Peter, the famous Biblical water-walker. Often birds become more agitated and flighty when the barometric pressure drops. Mariners noted this with petrels and thought the birds could predict a coming storm. Legends about petrels abound. When mean sea captains died their souls were thought to be condemned into these birds. As punishment for their cruelty the captains were damned to forever fly at sea and never come back to land.

In the South (where I hail from) the Green-backed Heron is sometimes called a shitepoke and the Great Blue Heron, the shite-up-the-creek. According to The Dictionary of American Bird Names this is “an attempt to render more delicate by a change in spelling, a name for the bird derived from its habit of ejecting effluent when making a startled departure.”

Oh shite, I gotta go.

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