People often ask if Maine’s island communities can really be expected to survive in the long run. Especially now — with food, fuel, ferries and energy prices soaring and the harvest of lobsters declining for the first time in over 15 years — the question has additional urgency. Matt Simmons, a prominent oil industry analyst and founder of the Rockland-based Ocean Energy Institute, believes that within the next dozen years the cost of diesel and heating fuels will rise to $10 a gallon. Without new sources of alternative energy from wind turbines and other sources, he says, Mainers will be spending half of their income, on average, on energy.

Island life is economically stressed. Not only do almost all the basics cost more on islands, but the means of earning a living are starkly limited. And yet, according statistics we gathered for Island Indicators (available online at www.islandinstitute.org), most island populations have either been stable or have slowly increased over the past decade. Since people haven’t stopped dying, it appears that a higher number of young islanders are choosing to stay on-island after they finish their schooling and/or other people are moving to island communities to embrace economic hardship. How can that be?

The answers lie in the essential qualities of island life. Islands select for individuals and families that are highly adaptive to changing conditions. In the most stable of times, island environments are more tempestuous than even nearby mainland environments. Unpredictable weather events are an inescapable fact of island life. Ferries and mail boats, not to mention your own boat or vehicle, break down at inopportune moments. In Mother Nature’s outback, you learn to develop back-up plans. And when your primary plan and your back-up plan fail, you rely on your extended family or neighbors. You get by; you adapt.

On the mainland, we live within the midst of — and at the mercy of — a vast service economy. But where and how do any of us fit in that vast network of available services? When something breaks down, we recognize that our families are far flung; we must wait our turn at any number of service providers — hopefully closer than Bangalore, India — but probably not much.

Last weekend our island tractor broke down for the second consecutive weekend, leaving several acres of wildly flourishing red top, Kentucky bluestem and timothy grass threatening to choke my father-in-law’s passion for an ordered pastoral scene. The mice had chewed the tractor’s gas line in several places over the winter and it was leaking gas at an alarming rate from its five-gallon tank, uncomfortably close to the island well. (A sole source aquifer has a deep meaning on islands). Aluminum pie plates from the island kitchen collected the immediate threat, but not for a five full gallons in the tank. An old island hose and a mouth-to-mouth siphon addressed this next problem, but left another: how do you rinse the taste of gas from your burning mouth lining? Hint: from filling gas tanks on the boat, my wife remembered that a bottle of Dawn liquid detergent disperses gas slicks, so I imbibed. However, I felt like I was blowing bubbles every time I exhaled for the next several hours.

Island communities are about shared experiences — from the most mundane to the most exalted. A few Saturdays ago, while driving off the ferry, we were surprised to see an enormous greeting committee at the end of the island ramp, with fire trucks and a large crowd — all celebrating the return of a young man from a series of cancer treatments. It’s hard to imagine a similar ceremony even in the most tight-knit mainland community. The meaning of community on the mainland is about where you work or send your children to school or, increasingly in Maine, where you retire.

Similarly, adaptation in island fisheries has been a way of life for 300 years. The first lobster trap hauler was probably invented by a fisherman, Clarence Howard from Eagle Island, who rigged a differential from an old Ford pickup truck on his lobster boat. Early on, islanders embraced purse seines to encircle schools of herring that evolved from stop seines, nets that closed off entire coves to catch herring schooling at night to feed.

Now island lobstermen must again adapt to new realities of lobster harvests that are still enormous by historical standards, but reduced from the stunning abundance of the last six-eight years. The existing business model for catching lobsters — bigger boats burning more diesel, setting as many traps as possible to carpet bomb your territory, and huge bait bags stuffed with expensive herring — will need to change. Island lobstermen are the closest to the edge of these new realities, and I think that these fishermen, from communities notorious for resisting change, will be the first to adapt. Because, in the end, change and adaptation are more constant on islands than anywhere else.

That’s why island communities will survive.