Lobsters and parrots show that figuring out invasive species is harder than it seems

Although the connection may not be immediately obvious, lobsters in Sweden are a lot like parrots in New Hampshire: Popular to some, worrisome to others, and reflective of how hard it is to preserve nature in an interconnected world.

“I’m always afraid of the things we don’t know about,”said Jason Smith, chief of the inland fisheries division of New Hampshire Fish and Game, one of several state agencies that decides which plants and animals are safe to let loose here.

The lobster saga arose last year with the discovery of three dozen American lobsters living in Sweden’s waters. Biologists fear they will get established and become a threat to the European crustaceans, so Sweden is pushing to have the American lobster declared an invasive species throughout the 28 nations of the European Union.

If that designation makes it through the complex EU regulatory system, it would block all import of lobsters from the U.S. and Canada to EU countries, a $200 million annual business. The North American lobster industry is, not surprisingly, up in arms: In Maine, an initial ruling against our crustaceans by the European Scientific Forum on Invasive Alien Species in Brussels was front-page news.

But what does this have to do with Granite State parrots?

Think back to 2011. That year, New Hampshire Fish and Game officers told a Nashua woman to get rid of a dozen Quaker parrots she owned because that species had been banned from New Hampshire for 23 years, out of fear they would become established here.

The birds, also known as monk parakeets, are an agricultural pest in South America and a nuisance in U.S. states as far north as Connecticut because they build huge communal nests that can break trees and damage transformers on utility poles.

But New Hampshire fans of Quaker parrots, including pet stores that at the time had sold perhaps 1,000 of the birds throughout the state despite the ban, responded quickly. They argued that our winters would kill off any birds that escape, which means they aren’t a long-term threat. (The lobster industry is making a similar argument against the proposed European ban.)

The argument held, and the state Senate removed Quaker parrots from a list of prohibited species. You can still buy them in local pet stores and so far, they haven’t become established in the wild.

Since then, New Hampshire has changed the way it handles invasive species. Lawmakers ditched the list of prohibited species, where the Quaker parrot once sat alongside snakehead fish and zebra mussels, and as of this year instead adopted a list of acceptable species. There the now-legal Quaker parrot sits alongside some 200 species of reptiles, amphibians, birds, fish and mammals that are native or already established, or are considered to be of no threat, ranging from brook trout to giraffes (although you need an exhibitor’s license for the latter).

This change in process helps officials deal with an increasing diversity of possible imports, said Smith.

“We oversee aquaculture. One of the things I get all the time is requests (to allow) a species I haven’t heard of,” he said. Previously, species that weren’t on the prohibited list would be allowed into the state. Now if a species isn’t on the accepted list, it’s up to the would-be importer to prove that it won’t cause a problem if it gets loose.

“Say an exhibitor wants to bring in something not on the list. They have to send it to the Fish and Game Department. It goes to a committee, takes a look at it, looks at where it’s coming from, make sure it’s not endangered . . . and determines whether it’s safe,” said Lt. Heidi Murphy, administrative lieutenant for the law enforcement division of Fish and Game.

Among the issues that the state can consider, as listed under rules known as Fis 800, are “history of diseases, pathogens and parasites in that or related species,” “interaction with indigenous species for food/habitat” and “ability of the species to survive in New Hampshire’s environment.”

These are the sort of qualities that turn a newcomer into an invasive species: Once transplanted, they thrive and out-compete or otherwise damage local species - usually because no natural predators exist here – and change the environment.

It’s complicated because not all exotic imports become invasive. Consider the pacu, a piranha-like fish that people buy for aquariums and then dump into the river for whatever reason. (In general, aquariums are considered to be a closed environment and not covered by exotic-species import laws.)

The pacu is certainly an exotic species that we don’t want here, but it’s not an invasive because it doesn’t thrive.

“They’ve been in Moore Reservoir in Lebanon. I’ve seen them come out of Merrimack (River) in Hooksett. But they typically don’t make it through the winter,” said Smith. “People catch it on a worm and a bobber, and bring it in saying, can you identify this? I say, unfortunately, yes I can.”

Controlling invasives isn’t state-specific. New Hampshire, for example, belongs to the Northeast Aquatic Nuisance Species Panel, an advisory body with representatives from New England, New York, and Canada’s Maritime provinces who swap information about freshwater and ocean exotics and help each other control them.

Preventing deliberate imports isn’t the only answer to preserving us from invasives. Plenty of new species come here on their own, especially with the climate changing.

“On the Seacoast, we’re seeing black sea bass show up. They’ve just moving up, due to a shift in the Gulf Stream,” said Doug Grout, chief of marine fisheries for Fish and Game.

Grout is also familiar with the green crab, an invader that is thriving in warmer waters and becoming a big problem for the shellfish industry.

“That’s been around for many, many decades,” he said. “The theory is that it came in the bilge of a tanker, or a boat. … It is almost completely established here.”

The state’s rules on imported species has a section that basically lets wildlife officials throw up their hands in despair and declare an invader to be “naturalized,” meaning “an exotic or an introduced species of wildlife that has become established in New Hampshire.”

Rainbow trout, for example, is a naturalized species. It was deliberately imported from the West to improve sport fishing and often out-competes native brook trout, but it is now so widespread and established that it is treated as if it was also a native.

“There can be a difference of opinion,” said Smith. “Certain species like largemouth bass, they’re great in certain areas, but there’s some line of thinking that they’re not good everywhere.”

And if you really want to get complicated, consider feral pigs. These are a very big problem in many southern states, where they destroy crops and dig up fields. For historical reasons – many related to the huge but secretive Corbin Park Hunting Preserve located around Croydon in western New Hampshire, which decades ago brought in wild boars for its members to hunt – they aren’t treated like any other potential invasive under state laws and regulations. You aren’t supposed to shoot one even if you see it on your own property, but instead notify its owner.

Wild boars have been reported occasionally in New Hampshire but they don’t seem to have established themselves outside of Corbin Park Preserve. Not yet, anyway.

All these efforts don’t even deal with invasive insects threatening our forests, such as hemlock wooly adelgid and emerald ash borer, or invasive plants like purple loosestrife in waterways, Eurasian milfoil in lakes and bittersweet strangling trees, or species you’ve never consider invasive like certain dandelions and even earthworms. But it’s still worth the effort, say officials.

“We want to make sure the ecosystem of New Hampshire remains a natural ecosystem,” said Lt. Murphy. “It’s something we don’t take lightly.”

And for good reason, she added: “Law enforcement officers have dealt with alligators that have been let go in the wild.”

(David Brooks can be reached at 369-3313 or dbrooks@cmonitor.com or on Twitter @GraniteGeek.)