SAN FRANCISCO — California anglers Monday hoped to see better catches coming in a day after the first full-fledged commercial salmon season in three years got off to a slow start.

Fishermen reported that salmon below the 27-inch minimum were plentiful on the season's opening day Sunday but mature fish difficult to find. Some blamed ocean conditions for the absence of the boatloads of fish still hoped for since state wildlife officials predicted a tripling in the coastal salmon population.

Projections of nearly 730,000 salmon in waters off the California coast in 2011 led federal fisheries regulators to approve the first full-length season since 2007. Cancelled seasons in 2008 and 2009 and a shortened season in 2010 left many fishermen struggling to make a living.

The commercial season this year is set to run as long as May through September off some areas of the Northern California coast.

The San Francisco Chronicle reports that high fuel prices have led some anglers to postpone their first trips to sea until reports come back of better salmon catches. Recreational anglers, who began fishing for salmon April 2, have not reported coming across many schools of the mature fish.

"I'm really happy to get back to work, but right now I think we have to take a wait-and-see attitude," Jason Salvato, a fourth-generation San Francisco salmon fisherman, told the newspaper. "Right now, I'm hearing the fish are small and scattered, so I'm going to wait."

The Pacific Coast Federation of Fishermen's Associations estimates that the plunging salmon population has resulted in at least $3 billion in losses and cost the industry 23,000 jobs.

The prediction for this year's ocean population is based mainly on the number of adult Chinook salmon in the Sacramento River fall run, which despite being smaller than expected saw a return to more normal levels after major drops in 2008 and 2009.

The California Department of Fish and Game calls the Sacramento River fall run the "main driver" of coastal commercial and sport salmon fishing.

Debate persists over the cause of the fish's sharp decline. Studies have suggested that cyclical ocean conditions led to the starvation of baby salmon.

Many fishermen blame the many pumps in the Sacramento-San Joaquin Delta that divert water for agriculture and city residents for hampering the ability of salmon to head upriver to spawn and back downriver to return to the sea. Farmers have long fought that claim.