July 7, 2007

Just a few miles away, the high-rising shoulders of Catalina lost themselves in low-hanging overcast.  The dawn sea looked pewter—moody and lovely.

Fishing was excellent but catching was slow, to paraphrase an old joke.  Our morning haul-back brought just two small Blue Sharks.  We did see an Ocean Sunfish (Mola mola) and glimpsed the swift fin of a Minke Whale (rhymes with kinky) and a big Risso’s Dolphin, and later a pod of Common Dolphins came streaking through the waves, shadowed by a retinue of Elegant Terns.  In other words, non-stop grace and wonderment, as usual.

On the afternoon haul, something simultaneously auspicious and ominous:  one of the braided cable leaders came up chewed through.  I would not have thought that possible.  It’s hard to imagine something capable of doing that and still being interested in sucking in one of our 10-inch mackerel, rather than, say, eating a sea lion, but odd stuff happens at sea.  The set brought two Mako pups.  Suzie invited me to do the tagging, which I duly did for the pups.

Then on one of the last hooks hung a larger Mako, about six feet long and about 170 pounds.  The larger animal would get the two kinds of electronic tags, and because applying these takes some practice, Suzie took over again.  She led the animal toward us with the leader, and as the cradle dipped into the sea she pulled it over the perforated metal and yelled, “Up!”  The water drained away and the Mako began thrashing, but we pounced on it as Erick Onate-Gonzalez put the thick blanket over its big black eyes, pulled up its pointy nose, and into the jaws of death inserted the ventilator hose.  Quite a job description.

One of the electronic tags bolts to the dorsal fin and transmits its presence to satellites when the shark is traveling at the sea surface, thus tracking its cross-ocean travels. 

 

The other tag looks a little like a cigar on a stalk that is anchored into the  muscle; it records temperature and depth, then releases itself at a pre-programmed time (about eight months from now), floats to the surface and tells satellites the story of the shark’s vertical travels between the surface and the cold, dark depths.  It’s incredible technology, revolutionizing our understanding of how animals use the ocean.  Turns out that though Makos frequent the surface, they often dive to a thousand feet, rarely twice that. 

While Suzie applied the tags, Erick held the head, kept its eyes covered and kept the ventilator in place.  That job takes nerve and concentration; you can’t get distracted or be caught by surprise if a shark this size suddenly thrashes.  I help “control” the tail, but in fact the shark stayed passive most of the time.  I had the distinct sensual pleasure of having my hands on that beautiful sleek, cobalt skin, with its fine-sandy teture, and the strong, thick keel at the tailstock’s base.  An exquisite, living sculpture; evolutionary art.

At one point as we rolled the shark slightly to check sex (male, indicated by its two penis-like misnamed “claspers”) the Mako started squirming and was working itself up to some violent thrashing.  Anyone who has caught them on rod and reel knows Makos are capable of literally spinning out of control.  I noticed that the blanked had slipped off its left eye, and when Eric quickly flapped it back on, the shark’s whole body instantly relaxed, its muscular tension utterly dissipating.

When Suzie yelled “Down!” and the cradle entered the water and we shoved that Mako forward, it took off like a shot.

And where do the sharks we’re catching in these relatively protected waters go?  The tracking affirms that these sharks range widely up and down the California Current, west to waters north of Hawaii, down off Mexico, and generally becoming vulnerable to fishing boats from other countries in the open ocean.  No sea is an island.

In the early 1990s there had been a small commercial fishery for sharks here.  It had a temporary permit, and the permit was not renewed because the area proved to be a shark nursery.  Thus this survey was born.  Would that such wisdom prevailed world-wide.

In the last two decades the number of sharks killed has skyrocketed, draining the sea of many of its most compelling predators.  I’ve seen the difference; the number of sharks we used to see in the 1980s was much greater than now.  Everyone I know who has a history at sea says the same, as do a series of recent scientific studies.

Tens of millions of sharks have been killed annually, mainly for fins used as a thickener in soup, mainly since the 1980s.  The number killed is almost certain to decline, not because international fisheries management—still dysfunctional over vast swaths of this planet—is likely to get its ass in gear anytime for the benefit of sharks, but because the sharks will grow progressively scarcer.

In the present survey, there’s some evidence of decline in this population but the trend is unclear.  Year-to-year variability, based in part on weather and water quality (for instance, blooms of toxic red tides) affects number of sharks caught.  So uncertainty remains about this shark community’s trajectory.  More time is likely to clear the picture.  But slow declines can be hard to detect for years, until real problems accumulate.  That’s a problem in itself, because it delays action.

For example, many populations of albatrosses have been declining at rates of around just 1% per year (coincidentally, mainly  because of incidental drowning in poorly regulated long-line fisheries.)  It took too long for scientists to determine the declines were real, sustained, and significant.  But over the course of just one working career for the scientists who were monitoring albatrosses, declines of 1% annually became population emergencies threatening some albatrosses with extinction.  And yet in the last decade some real progress has been made in reducing albatross deaths.  Bright spots include Alaska, Hawaii, New Zealand, the Falklands, South Georgia Island, and the Southern Ocean.  That progress matters; it may yet save threatened albatrosses.

It also suggest that despite the history of most fisheries management worldwide, there remains hope for sharks.  Certainly, these sharks we’re catching, many of them quite young, constitute hope with a mischievous grin.

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