In sports, knowing the opponent is half the battle. Experienced anglers know that picking the right spot is the best guaranteed way to result in a catch. To do so, fishers must understand the ecosystems which a species prefers and the water’s climate.

“The big trick is just finding where they are in the water column,” said Roger Urbaniak, a member of Puget Sound Anglers of Lake Washington (PSA of Lake Washington). Urbaniak teaches classes, both on the Island and in Bellevue, about fishing in Lake Washington. Through the Bellevue Parks and Recreation Department, Urbaniak shows off the tricks of the trade and helps youth on the Island learn about dock fishing at Luther Burbank Park.

Another biggie for the success of an outing is knowing where in the water a specific type of fish may be. The time of year dictates where the fish are likely swimming, Urbaniak said. Cold-water fish, such as trout or salmon, which frequent Lake Washington, prefer water temperatures of 59 degrees or colder, while warm-water fish, such as bass and perch, like waters above 59 degrees. What makes this time of year interesting, Urbaniak said, is a phenomenon called thermocline. Twice a year, the water temperatures in the lake effectively switch positions. Usually, around May 1, the warmer water rises due to increased sun exposure, coming to rest near the top of the lake while the cold water sinks, taking cold-water fish along with it.

Right now, Urbaniak said, anyone interested in fishing for warm-water fish should try in shallower water where the temperatures are warmer. For those cold-water species, plan to fish in deeper waters, around 30 feet or more, Urbaniak suggested.

Sean Considine, a resident of Federal Way, took advantage of the change while fishing for bass last week at Luther Burbank Park. He said he has been coming to the park for the past five to six years to take in the peace and quiet, and to see what’s biting.

“I enjoy the park and like freshwater fishing,” he said. “I’m hopeful for the season.”

An experienced angler knows that the next trick is finding the fish. Every fisherman has personal preferences honed over past experience and based on common knowledge, but historically, a great place for trout is along the I-90 bridge, Urbaniak said. This is because wind concentrates plankton along the bridge. Plankton draws in minnows, the small fish that trout love to eat, thus creating a cluster of trout.

Urbaniak said that in reality this rule applies everywhere — fish are drawn to what he called “structures,” a type of mass within the water. A structure could be a dock, a bridge or even a group of weeds. It gives the fish someplace to hide and provides the ecosystem necessary to survive.

“Locating a structure is kind of the key to locating fish,” he said. “Open flat areas of water just don’t support the needs.”

Steve Marsh, another angler with the PSA of Lake Washington, said that some of his favorite spots around the Island are Luther Burbank, Clark Beach and Groveland Park for bank fishing. Off Island, he recommends Seward Park and Gene Coulon Park.

A fishing license is required for anyone 15 years old and over, and can be purchased at the Washington Department of Fish and Wildlife’s Web site: wdfw.wa.gov/licensing.

Currently, there is a fishing advisory from the Washington Department of Health (DOH) for certain types of fish within Lake Washington. Anglers and people who eat fish from the lake are being told not to eat Northern Pikeminnow, also known as squawfish, and to limit consumption of yellow perch and cutthroat trout due to increased levels of polychlorinated biphenyls (PCBs) which could cause human health problems. For more information on fish advisories, visit www.doh.wa.gov/ehp/oehas/fish/fishadvisories.htm.

Also be sure to check www.boat.wa.gov, the state’s new boating Web site, for advisories, licenses and other important information to know before hitting the water.

For more information on Roger Urbaniak’s fishing classes, contact the Mercer Island Parks and Recreation Department at (206) 275-7609.