New Home For Iceworms, Y'all
From Robert Service's poetic reports about the Klondike in 1898 to the likely media coverage in 1998 of Cordova's annual celebration in its name, the iceworm is a creature claimed by the north. True, the world first knew the creature as fiction: Service's drink-garnishing iceworm was merely an artfully decorated bit of pasta. Cordova's iceworm festival acknowledges art as well, since there the official parade-participating iceworm, with its many booted feet, is no more real than the dancing dragon in a Chinese new year celebration.
Even so, northerners know that real iceworms live in our territory. Specifically, they live within our glaciers, where they browse on hardy algae, pollen grains, and spores carried in by the wind. The threadlike iceworms and their algal pastures actually are found in water on and in the glaciers, not within the crystalline ice itself. The inch-long worms need that water, but even in winter, glaciers as far north as the Alaska Range offer enough unfrozen water to provide safe haven for iceworms.
When someone told me that iceworms aren't really worms at all, that watery way of life was part of the proof. If they're really larval midges, the juvenile life stage of a small flying insect, as my would-be instructor claimed, then they'd behave exactly as iceworms do. The usual home for midge larvae is the bottom of lakes or ponds, but mostly they do look rather wormy and they do eat algae and other plant material.
I liked the idea of iceworms being infant midges, heretical though it seemed. It meant that when iceworms leave home, they don't crawl away. Instead, they shed their wormy skins, sprout wings, and fly off, kind of like Prudhoe Bay workers doffing their parkas and leaving on jet planes.
But while I was trying to verify this version of iceworm reality, I came across a research report that seems even harder to believe. At an oilfield far south of Prudhoe, a whole new family of iceworms has been found. There's no question that these creatures are true worms; they're bristleworms, or polychaetes (pronounced, approximately, polly-keets). Polychaetes are among the common types of sea-dwelling worms, which is appropriate, since these iceworms live deep down in the Gulf of Mexico--in methane ice.
Geophysical Institute Science Writer Ned Rozell described methane ice, which is one kind of gas hydrate, in this column back in January . It's odd stuff, forming only where the right combination of high pressures and low temperatures permit, in which ice molecules form a rigid cage enclosing natural gas and other hydrocarbons. There's a lot of it at Prudhoe Bay and elsewhere in Alaska, which may be good news for the state budget since it's a promising energy source.
Evidently these polychaetes also think methane ice is a fine energy source. When scientists aboard a research submersible checked out a newly exposed bulge of methane ice on the sea floor, they found its surface pocked with a myriad of tiny dimples. In each dimple wriggled a pale pink worm, its body fringed with a row of white bristles on each side. During later dives, the scientists were able to carve off a chunk of the wormy hydrate and bring it safely to the surface in a pressure chamber. They found the whole thing was riddled with worm burrows.
Since the first worms observed were well ensconced in methane ice that had just erupted through the thick sediment underlying the Gulf of Mexico, the scientists suspect these new iceworms may have been living in the hydrate while it was buried farther down. Though the biologists associated with the project are fascinated by this new species with the odd diet, the petroleum prospectors are a bit worried. How much valuable hydrate are these iceworms mining away? Maybe we should be glad that our glacier-dwelling iceworms like algae, and maybe we should hope the drills at Prudhoe don't encounter any methane-loving iceworms.
