American University professor David Culver spent a week in April hunting through damp spots in the forest floor in Montgomery County in hope of finding rare varieties of tiny, shrimp-like creatures called amphipods.

He didn’t find any. Not a one.

This might have been a major setback for the folks who hired the environmental scientist. They’re paying Culver thousands of dollars with the goal of blocking plans for the light-rail Purple Line in suburban Maryland on grounds that it threatens the critters with extinction.

But they can’t make their case if the miniature crustaceans aren’t there to protect.

So, did Culver’s failure stop opponents from suing to thwart the project under the Endangered Species Act?

No way! They went right ahead and filed a federal civil complaint on Tuesday.

It’s all just a legal gimmick, of course.

Having failed to kill or reroute the Purple Line despite years of agitation, a small but resolute band of critics is exploiting a pair of amphipod species in what could be the final, serious bid to disrupt the transit project.

It would be a shame if they succeed, and not only because the Purple Line would create a long-overdue transit rail link between Montgomery and Prince George’s counties.

The Purple Line also would be a significant plus for our region’s overall environment, which is why leading green organizations — including the Sierra Club, Chesapeake Bay Foundation and Natural Resources Defense Council — support it.

The Purple Line would help pack more people into the inner suburbs with access to transit. The “smart growth” goal is to encourage the region to grow denser in the middle rather than wider around the edges.

That reduces the need to build another ring of outer suburban sprawl, which would eat up green space and add to commuting times.

Must we pay a price? Absolutely.

As I’ve noted before, building the Purple Line will require bulldozing 17 acres of mature forest. It will spoil the bucolic atmosphere along the Georgetown Branch walking and biking trail, an extension of the better-known Capital Crescent Trail.

And yes, it would be a shame to threaten the survival of any of God’s creatures, even a mini-shrimp of no particular value apart from its singularity as a species.

“I do not think that, say, in Rock Creek they’re important in the ecosystem,” said Culver, a leading expert on amphipod habitat.

But wise stewardship of the environment requires making choices, and this one is easy.

“Any major project . . . is going to have some negatives,” David Sears, vice chairman of the Sierra Club in Montgomery County, said. “It’s our considered opinion that the net plus is considerable, and the Purple Line is the way we want to go.”

Sears called the amphipod lawsuit “a delaying tactic” and said its arguments were “really stretching things.”

The lawsuit’s fate will rest partly on whether Culver can find any amphipods when he looks again in the autumn. He said he didn’t look as thoroughly as he would have liked in April because he didn’t yet have a state permit to collect them.

The Hay’s Spring and Kenk’s amphipods might be at risk, he said, but added: “First, we have to show that they’re there.”

Of the three plaintiffs in the lawsuit, one has no business at all making such cynical use of the Endangered Species Act. The Friends of the Capital Crescent Trail wouldn’t care a whit about amphipods except for their legal utility.

The group also twists the facts when it claims that the Purple Line would “destroy” the biking and walking track.

The project would pave and widen the Georgetown Branch Trail and operate light-rail trains alongside it. But a path would continue to exist.

The other plaintiffs, John M. Fitzgerald and Christine Real de Azua, have a more legitimate claim. Both are longtime environmentalists who have worked professionally to protect biodiversity.

On the other hand, they also live a half-block from the Purple Line’s route, in the Town of Chevy Chase. Its residents have been mainly concerned with shifting the transit line into somebody else’s back yard.

In the 45-page court filing, Fitzgerald and Real de Azua said they felt a “special and unique bond” with the amphipods’ habitat.

That’s curious, because one of the species, the Hay’s variety, has never been sighted outside the District.

If their bond with a blind, pale, half-inch-long crustacean is really so meaningful, then I suggest they move across the Western Avenue border to be closer to it.

For previous columns, go to