Climate what? Of gulf streams and the apocalypse caterpillar

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I sat on my front stoop on one of the first legitimately brisk mornings this winter admiring a caterpillar that had coiled itself into the cinnamon roll configuration a caterpillar assumes when a giant hand suddenly descends to pluck it from a leaf pile. This species — I grew up on the name “woolly bear” — has black segments at the head and tail, and a rich brown section in between.

Some believe the continued decline of striper landings is a response to mounting strains, including cli-mate change and its effect on the environment.

An old wives’ tale maintains that the proportional relationship between black and brown foretells the duration and severity of the winter season. Of course, as I stood stiff and motionless as a two-by-four in the dawn air, I’ll be damned if I could remember which color represented a mild or severe winter.

It seemed significant only because this poor bugger’s black “head” band ended just behind its eyes. The brown segment stretched all the way to the tail. I had never, through a lifetime of eerily mild and interminable frozen-tundra winters, seen a woolly bear with such coloration. In my precaffeinated stupor, a state that often leaves me prone to moments of breathtaking stupidity, it struck me that this furry critter was an omen of some sort.

I should point out that during the week that preceded the arrival of the apocalypse caterpillar, I had gone on a wild climate-change reading bender during which I mowed through several hundred pages of backlogged articles and essays, some grounded in science, some in policy, some in pure rhetoric. My head was packed to capacity with terrifying anecdotes about frighteningly abrupt shifts in weather and oceanographic patterns — huge changes in salinity, plankton growth and distribution, and corresponding trends in the distribution of the Gulf of Maine’s besieged codfish, flounder, mackerel, lobster and crab stocks, for example.

There’s been a load of work published on the implications of accelerating polar-ice melt and unprecedented changes in such ocean currents as the Labrador Current and the Gulf Stream. Ever since NOAA Fisheries declared disaster within the Gulf of Maine and Georges Bank groundfisheries, scientists have been working overtime to fast-track what had been a softer priority of incorporating climate-change data into fisheries stock-assessment processes. Given that regulators have had such difficulty incorporating “ecosystem” data — i.e., the interspecies relationships that decision makers have long needed to get a more holistic view of fish abundance within a specific area — it’s not a shocker that we’re still quite a ways from beginning to quantify the complex effects that changing oceanography is having on managed fish stocks.

In the much more contained ecosystem of the just-over-half-acre that is my yard, climate change has moved from a vague abstraction to a tangible, observable reality, though in fairness I’d be reluctant to explain how, specifically, I know that is the case. Before the endless-summer/endless-winter caterpillar made its appearance, 2015 had rolled out all kinds of ecological and weather oddities, including a fall that sprawled right through December into early January.

After a near-pestilence of invasive winter-moth caterpillars devoured much of the greenery on maples and other deciduous trees in my area last spring and early summer, my family and I observed a proliferation of woodpeckers and other small birds. And as summer yielded to the slightly cooler weather of October, rainfall never materialized. The water table bottomed out, with local streams and ponds lower than I’ve ever seen them during hurricane season.

Yet somehow, despite the exceptionally dry year, friends and I noticed a dizzying abundance of mushrooms and other fungal growth. Apple and peach trees dumped extraordinary payloads of fruit. The tomato yield in the average vegetable garden in town skyrocketed. Perhaps, as one of my more flora-attuned friends suggests, this reflects the known commodity that plants under stress of drought or other climatic variables tend to push out greater numbers of seed-bearing fruit as an insurance plan for survival.

Biologists point to similar patterns among fish (striped bass, notably) spawning during periods when the stock is subjected to environmental or biological stressors. Some researchers have suggested, for example, that the record-breaking 2012 year-class of Chesapeake Bay stripers reflects not a greatly underestimated spawning stock but rather a natural, hard-wired response to a host of mounting strains. I’m straying from the point here.

Through a year of winter moths, woodpeckers, fungi, drought and fruit production, fellow anglers and I observed a mass influx of full-grown menhaden from June through December. Striper landings followed their generalized downward trajectory on a whole-fleet, all-season basis, even as surfmen in my area declared 2015’s fall-run casting the best in a decade. Bluefish were scarce. Fluke fishing was discouraging until midsummer, when a huge shot of large fish moved in at Block Island. Sea bass were thick on nearly every piece of hard bottom in Rhode Island state waters — and everywhere else from Cape Cod to Virginia.

The state overshot its landings targets for fluke, sea bass and scup by wide margins, if one believes the recreational survey data that say so. Recreational fishermen, who live and die by the system’s numeric output, tend not to. But really, that’s not the point, either.

I’m having real trouble imagining a valid way to splice anything as dynamic as climate change into the current wood-fired, one-horse, one-stock equations of fish abundance. It’s nothing against science. I believe in the power of random sampling and carefully rendered statistics, so long as the numbers are used as advertised and with a clear sense of their limitations.

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Legislative rhetoric be damned, until we embrace the interconnectedness of various species with overlapping terrain (via predator-prey or same-tier-predator relationships) in the present tense of stock assessment, the idea that we can successfully account for the impact of shifting climate on the distribution of a given fish is a pipe dream.

For the moment, I’m working on climate change where I see it in my yard or in the waters I fish often enough to absorb fine detail. I’m working to strip the term of all the boogeyman-style menace rhetoricians have hard-wired into the words — to see the phenomenon for what it is: an expansive, multilayered network of small, often subtle shifts buried in the minute detail and the long-term averages of an ecosystem in action.

Climate change isn’t the 60-degree day in early January; it’s the 30-degree spike in air temperature over eight hours, and the 23-degree nosedive 20 hours later. It’s the number of violent fluctuations to and fro across the seasonal averages in both directions over a set period. It’s the spring-like false starts — new growth popping in a flower bed in January — that are wiped out by a 6-degree Arctic freeze two days later.

A more useful worry than the next supermegatornadocane is how we might come up with a standardized unit of measurement to help us add, subtract or multiply caterpillars by droughts, or record-high summer days by woodpeckers, less average total peaches per orchard times striperless bunker schools per square nautical mile of water.

Now that I think of it, the brown section in the middle is winter — the wider the brown section, the milder the … Aunt Sue knows. Or was it Uncle Bob? Either way, the sun’s up, and I’ve got a caterpillar to find.

This article originally appeared in the March 2016 issue.