A variety of rare and threatened species have been denied protection under the Endangered Species Act (ESA) in recent weeks, including North America's smallest rabbit and a plant that may already be extinct in the wild.

The U.S. Fish and Wildlife Service (FWS), which makes the final determination on which species get protected status, ruled that some of these species deserve protection, although not as much as other, higher priority species. FWS also said it lacks the funding to add some of these species to the endangered species list at this time.

The most recently denied species is the Sacramento splittail (Pogonichthys macrolepidotus), a minnow that was listed as threatened under the ESA from 1999 to 2003 then removed after a lawsuit from the San Luis and Delta–Mendota Water Authority in California. After seven years of additional review spurred by another lawsuit from the Center for Biological Diversity (CBD), FWS ruled on Tuesday that the splittail does not warrant ESA protection, saying "while habitat loss has occurred over the years, the existing data fail to show a significant long-term decline of the splittail." The splittail can be one of the region's most abundant fish, but only during flood years, which California has not experienced lately. The CBD says it will challenge this most recent decision.

Another tiny species, the pygmy rabbit (Brachylagus idahoensis), was denied ESA protection on September 29. The decision affects the rabbit's dwindling populations in California, Nevada, Oregon, Idaho, Utah, Wyoming and Montana; a population in Washington State was protected under the ESA in 2003. North America's smallest rabbit, the species weighs less than a pound in adulthood. A shrinking gene pool has left the animals prone to infection.

A few days earlier FWS acknowledged that the Gunnison sage grouse (Centrocercus minimus) deserves protection, but the service lacks the funds to do so. The sage-grouse has lost 90 percent of its natural habitat (possibly due to oil and natural gas development projects), and can now only be found in Colorado and Utah. Al Pfister, an FWS field supervisor, told Colorado's The Watch newspaper that further steps to propose critical habitat for the sage grouse could come in fiscal year 2011 or 2012. The U.S. Agriculture and Interior departments announced a plan to protect the habitat of a related species, the greater sage grouse (C. urophasianus), in 11 western states in April.

Elsewhere, a rare plant known only by its scientific name, Agave eggersiana, which may actually be extinct in the wild, was denied protected status until funding to protect it becomes available. The plant is found only on Saint Croix in the U.S. Virgin Islands, where most of its suitable habitat is scheduled for residential development.

In related news the FWS has won a court case which will allow it to remove bald eagles (Haliaeetus leucocephalus) in Arizona from the endangered species list. Bald eagles in the rest of the country were taken off the list in June 2007, although they are still protected under other federal and state laws.

Photo: Pygmy rabbit by H. Ulmschneider (U.S. Bureau of Land Management) and R. Dixon (Idaho Fish and Game). Courtesy of U.S. Fish and Wildlife Service