“It’s just an historic imbalance that needs to be righted,” said Bethany Cotton, wildlife program director for the organization, which is based in Santa Fe, N.M. With most efforts to protect species started by groups and individuals, the overwhelming majority of species listed have been the ones people can see — land- and river-based wildlife, predominantly in the West, she said.
The marine exceptions to that have been “really charismatic mega-fauna,” such as whales and dolphins, Cotton said, as well as some turtles, seals and salmon.
Experts not associated with the organization offered other explanations. “There are two factors that explain why there is such an imbalance,” said Ellen K. Pikitch, executive director of the Institute for Ocean Conservation Science at Stony Brook University.
“People have had this idea for way too long that the seas are so vast and limitless that nothing we could ever do could hurt them,” she said. “It’s hard to shake that.”
In addition, Pikitch said, while humans have been fishing for sturgeon since 3000 B.C., the heaviest exploitation of marine resources has come in the decades since World War II, with the use of huge, powerful fishing craft that can go far out into the ocean and the development of the capability to process and freeze fish at sea.
“We’ve only recently just arrived at this point,” she said. “That does explain why we don’t see more species that were on the list in the beginning.”
Boris Worm, a professor of marine biology at Dalhousie University in Halifax, Nova Scotia, noted that global extinction of marine species has been historically rare and that no fish species has been completely eliminated from the waters that cover 71 percent of the globe. (A number of species, including some sturgeon, bluefin tuna and white marlin, have become extinct in certain regions, which often signals the onset of a more widespread problem, he said.)
Even though 9 percent of fish species qualify as threatened, the data make people less likely to believe they will be killed off entirely, Worm said. “Marine species are probably somewhat less likely to go extinct, probably, to a certain extent, because we have more difficulty tracking them down,” he said. In contrast, humans have succeeded in wiping out hundreds of land-based species, he said.
And Miyoko Sakashita, oceans director for the Center for Biological Diversity, an advocacy group, said scientific knowledge of the oceans has lagged behind assessments of land.
“I would say our ocean ecosystems are very much at risk, just like our terrestrial ecosystems, especially with ocean acidification and warming waters,” Sakashita said. But “there hasn’t been as much funding and focus on understanding” marine habitats, she said.
In asking the National Marine Fisheries Service to nearly double the number of protected species, WildEarth Guardians cited the basking shark, the blackchin guitarfish and tiny corals among the 75 populations and six subpopulations it says are most imperiled.
“Our oceans and the species that call them home are facing unprecedented threats from fishing, ocean acidification, pollution from toxic runoff and dumping of waste at sea,” Cotton said. “Our petition seeks legal protections for 81 of the most imperiled marine species.”
In an e-mail, Connie Barclay, a spokeswoman for the National Oceanic and Atmospheric Administration’s Fisheries Service, said the agency’s endangered-species team had not seen the petition from WildEarth Guardians and could not comment.
Sakashita said studies by her organization show that protection under the Endangered Species Act is an effective way to restore a species to health. One such review issued in 2012 asserted that “90 percent of species are recovering at the rate specified by their federal recovery plan.” Another suggested that the longer an animal was listed as threatened or endangered, the more likely it was to have an improving population trend.