TOAD SHOWDOWN; EDUCATOR SAYS DAMS HURT HABITAT.

Byline: Charles F. Bostwick Daily News Staff Writer

Off-road enthusiasts, campers and anglers didn't make the arroyo southwestern toad an endangered species.

No, the gravel-colored amphibian is in danger of extinction because Southern Californians for over a century have dammed, paved and otherwise used every river or stream for all it was worth, a prominent expert says.

``Arroyo toads are seriously in trouble as a species,'' University of California, Santa Barbara, professor Samuel Sweet said in an interview last week. ``It's not due to any one particular thing, other than the fact they need to live in a stream bed. If Southern Californians have done one thing, they've messed up stream beds.''

On Jan. 25, U.S. Forest Service officials closed off nearly five square miles of Angeles National Forest - including a campground and about 17 miles of off-road vehicle trails - upstream from Littlerock Reservoir to help ensure the survival of the arroyo toad, Bufo microscaphus californicus.

The 3,000 acres will remain closed until 2003 while biologists examine the area for the precise locations of toad populations and other endangered or threatened species.

The closure effectively shuts down the Littlerock off-road vehicle area - one of three in Angeles National Forest - except when Littlerock Reservoir's water level drops enough to let vehicles on what is normally lake bed.

It also shuts down the Basin campground, bars anglers from Little Rock Creek upstream from the reservoir, and closes a popular off-road vehicle route up Santiago Canyon.

Angeles National Forest Supervisor Michael J. Rogers, in a letter to U.S. Rep. Howard P. ``Buck'' McKeon, R-Santa Clarita, off-road groups and other individuals and organizations, said forest officials could be held personally responsible for the killing of even a single toad, declared endangered in 1994.

Temporary closures of a smaller area along the creek each spring and summer - the toad's breeding season - for three years hadn't worked, Rogers said, because too many people ignored the signs and a fence.

The closure led leaders of one group, Public Lands for the People, to say they intend to appeal the decision to Rogers' Forest Service superiors. McKeon aides said they are looking into the situation. Off-roaders talked about circulating petitions and said the closure would just push people into more fragile areas where more damage would be done.

Sweet, one of two amphibian experts who petitioned the federal government in 1992 to declare the arroyo toad an endangered species, said the Endangered Species Act forces the Forest Service's actions.

The law does not allow wildlife officials to decide a certain population of a species is too far gone to save, or that banning one type of human behavior will have little effect, or to concentrate efforts where it would do the most good, Sweet said.

The law gives the same protection to every individual of an endangered species, whether it's a single pinhead-sized toad egg or an adult California condor, which Sweet says makes no sense biologically.

``The law says `Ye shall not,' '' Sweet said. ``The law doesn't give you any wiggle.''

The arroyo toad's problem is not really the use of motorcycles in Littlerock Creek, Sweet said, although off-road vehicles or even crowds of people in a campground can smash large numbers of toads, especially when the toads are most vulnerable in streambeds during the summer.

``The problem is, people need water and there's a lot of people in Southern California,'' Sweet said.

Virtually everywhere the arroyo toad once lived, from Monterey County to Baja California, dams have been built, Sweet said. Dams inundate the sandy terraces, gravel bars and shallow pools where the toads breed and live, and strip the downstream channel of silt, leaving rocks and boulders.

While the toads survive Southern California streams' periodic floods because they crawl to higher ground in winter, releasing a wall of water from a dam in late spring or summer can wash away thousands, he said.

The result of dams and other changes, like turning most Southland rivers into concrete channels, is to isolate toads into small populations at the far upstream ends of the smallest streams, Sweet said.

If a population in one stream is killed off, by road building or off-road vehicles or even campers catching toads, the other populations are too far away to re-populate it.

But Sweet believes the arroyo toad can be saved.

U.S. Fish and Wildlife Service officials are making the second revision to a recovery plan that will lay out steps for boosting toad populations to the point it can be removed from the endangered species list.

One major step is to manage dams so that releases of water as much as possible mimic natural flows, he said, instead of alternately drying up a creek or turning it into whitewater.

Even before the toad was declared endangered, that was done for Pyramid Dam on Piru Creek, a major arroyo toad habitat in Ventura County.