LONG BEACH, Calif.-- When it comes to getting some much-needed rain in California, El Niño has been a letdown -- at least so far.

But as CBS Los Angeles reports, the weather phenomenon may be responsible for pushing rare sea creatures into California waters.

Diver Roger Hanson told CBS LA he couldn't believe what he found twice Sunday just off the Long Beach coast: a rare Pacific seahorse calmly gliding above the ocean floor in just a few feet of water.

Diver Roger Hanson. CBS Los Angeles

"I was shocked," said Hanson.

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Hanson had last spotted the spiny curvaceous creature last month, but his determination to capture this seahorse on camera in the chilly water came with a price.

"Once I saw the seahorse, I stayed out a little bit too long and got out of the hospital this morning at seven (a.m.)," he said.

Marine experts said warmer waters possibly from El Niño might be attracting this vulnerable species into the waters of Alamitos Bay. Usually they're found among the coral reefs as far south as Peru and hardly ever found north of San Diego.

And experts said there are more creatures surprising us this winter: in San Diego, there are jellyfish blooms and even sightings of venomous yellow-belied sea snakes.

In more than 5,000 dives, Hanson said he has come across some dangerous creatures, including a Great White shark.

"Cousteau said you never know what you're going to see on your next dive," according to Hanson.

Hanson -- who usually monitors an octopus den in the bay -- is set to receive another prestigious diving award in the fall.

But first, he said he's eager to get back out in the water in search of more seahorses.

"There's got to be more than one," he said. "That's my next mission."