Fragile Fish: NRDC Fights for California's Endangered Tidewater Goby
LOS ANGELES (April 15, 2009) – In an attempt to save a unique and endangered fish found only in the most fragile of California coastal habitats, the Natural Resources Defense Council (NRDC) will file a suit today against the U.S. Fish & Wildlife Service after habitat protections were needlessly limited. NRDC fought to keep the fish on the Endangered Species List in 2000, and now a removal of habitat that the Service had previously labeled as essential to the species’ survival have forced a return to the courts.
“Tidewater gobies are uniquely Californian,” said NRDC attorney Rebecca Riley. “They live in pockets of brackish habitat along the coastline that have become increasingly fragmented over the years. The Fish and Wildlife Service needs to protect more of these fragile marshes, estuaries, and lagoons to ensure the recovery of this exceptional species.”
Tidewater gobies are only found in small pockets along the California coastline; from Del Norte County in the north, to San Diego County in the south. The small fish is uniquely adapted to living in the brackish waters that characterize one of the Golden State’s most imperiled ecosystems -- its coastal salt water marshes and lagoons. The fish’s reliance on these disappearing spaces is central to the Service’s “critical habitat designation” (the areas that receive special protections under the Endangered Species Act). In 2008, the Service revised this designation and excluded all brackish habitat that was currently unoccupied by the fish. This change was contrary to clear language discussing the need to protect unoccupied habitat in both the original habitat designation and the Service’s 2005 recovery plan for the goby. No explanation for the change was made.
Though sizable populations of the fish can still be found in spots along California’s coast, most of the salt water marshes, lagoons, and estuaries that the gobies call home have long disappeared. Approximately 90% of the state’s wetlands have been destroyed since the days of the gold rush. In the past, when drought or changing conditions killed off the goby populations in one area, tidewater gobies from a neighboring brackish area would re-colonize. This shifting of populations rarely occurs today due to the disconnected, patchy nature of their habitat. Scientists are concerned that the mercurial changes to water level and quality that are typical of brackish ecosystems makes the goby’s population fluxes vulnerable to collapse without the added habitat connectivity afforded by some of the currently unpopulated areas.
Tidewater Goby Tidbits:
While these fish are somewhat drab in appearance, their unusual behavior is quite striking:
- The 2-3 inch gobies live for about a year and are not closely related to other fish (they are the only species of their genus).
- They live their whole lives in shallow, brackish water (where salt and fresh water mix) of marshes, estuaries, and lagoons on California’s coast. These are extremely fragile places and some of the state’s most endangered ecosystems due to agricultural and sewage effluents, changes in water flow, and unnatural breaching of the sand dunes that create lagoons.
- The fish cannot live long if flushed out to sea by the tides. Perhaps because of this, they have fused front fins that seem to act like a suction cup to help them stay on the seafloor.
- Tidewater gobies have uniquely reversed sex roles unlike most any other fish species; females are more colorful and aggressively battle for the right to mate.
- In April or May, males dig out breeding chambers with their fins and mouths -- excreting mucous to strengthen the tunnels.
- Females enter the chambers, breed and depart after dumping their eggs, which the males nurture and guard until the young emerge 9-10 days later.
- The Fish & Wildlife Service maintains a gallery of Tidewater goby images at http://www.fws.gov/arcata/es/fish/Goby/gallery/goby_gallery.html
- The University of California also maintains a gallery of Tidewater goby images
- More info on the Switchboard blog at http://switchboard.nrdc.org/