With 170 inches of rain a year — compared with 37 in Seattle — Palmyra also has a dense rain forest where 11 species of seabirds nest. Discoveries made there include a surprising link between fish and seabirds: a study found that nesting birds’ droppings carried onto the reef by the rain stimulated plankton growth that attracted manta rays and other plankton feeders.
Other research has shown that the classic picture of a coral reef, with lots of pretty little fish and a few big ones, is entirely artificial. Palmyra’s reefs, like those in the other monuments, are dominated by sharks, snappers, jacks and other top predators, while smaller prey cower in fear in holes in the coral, a study found.
So interconnected are the elements of intact reef communities that allowing fishing just beyond 12 miles would disrupt the ecosystem, said Alan Friedlander, a marine ecologist at the University of Hawaii and chief scientist of the National Geographic Society’s Pristine Seas project.
“You need to keep the fishing as far away as possible, ideally at 200 miles,” said Dr. Friedlander.
Moreover, the remote locations are difficult to police. Many of the denizens of intact tropical reefs, like humphead parrotfish and wrasses, are worth thousands of dollars in Asia, said Dr. Richmond.
“Fishing them sustainably, as Wespac proposes, would mean traveling very long distances from Hawaii and taking very few fish,” he said. “It wouldn’t be economical.” Dr. Richmond predicted that fishing vessels “would poach the heck out of those islands.”
Daniel Pauly, a prominent fisheries scientist at the University of British Columbia, says that given a chance, the value of the bigger reserves like those around Wake and Johnston atolls and Jarvis Island, which extend to 200 miles offshore, will increase over time.
Research by Jonathan A. Mee, a fish geneticist at Mount Royal University in Calgary, Alberta, suggests that in any large marine reserve, some “lazy” fish will spend their whole lives inside the boundaries and therefore will not be caught — and the bigger the reserve, the more fish inside it will live longer.
This will raise the number of what scientists call B.O.F.F.s (Big Old Fecund Females), which produce more eggs and eggs of better quality, further increasing the density of fish inside the reserve. Dr. Mee believes that evolutionary selection of a putative “lazy” gene would accelerate the population growth inside a reserve.
“The bigger the mortality outside the reserve, the faster the population inside will grow,” Dr. Mee said in an interview.
This would be particularly helpful for bigeye tuna, which is the mainstay of the sushi market and the principal target of the Hawaii long-line fleet. The population of bigeye in the central and western Pacific is now estimated to be 16 percent of its original size.
“Technology and subsidies have allowed industrial fleets to go farther and farther, and deeper and deeper, and to deplete stock after stock,” said Dr. Pauly, who has shown that the global catch is steadily falling.
“The only thing standing between these fleets and global depletion are these big no-take reserves, so this is the time to create more, not to open up the existing ones to fishing.”
Alex David Rogers, a conservation biologist and seamount expert at Oxford University, estimated that worldwide there were about 16,000 seamounts with summits above 5,000 feet, shallow enough to harbor a rich diversity of fish and corals. Unfortunately, he said, most have already been fished.
Still, those seamounts in the Papahānaumokuākea and Pacific Remote Islands marine monuments remain mostly pristine, said Chris Yesson, an expert on ocean floors at the Zoological Society of London.
“Saving the ones in the American marine monuments is extremely important, because the NW Pacific is particularly rich in endemic corals and other marine life,” Dr. Rogers wrote in an email.
Paul Achitoff, managing attorney for Earthjustice’s mid-Pacific office in Honolulu, said many legal scholars had concluded that the Antiquities Act, which allows presidents to designate and protect monuments without congressional approval, is a one-way street.
“It does not allow presidents to remove restrictions or protections from a previously designated monument,” he said in an interview. “Only Congress can do that.”
He acknowledged that several presidents had changed monument boundaries and tweaked restrictions without court challenges.
That may change soon. “If any of the protections to the Pacific marine monuments are lifted, we will be filing lawsuits, and we expect to win,” Mr. Achitoff said.