Each week one of the Salmon University experts answers reader questions in our “Ask a Pro” feature. This week’s questions are answered by Tom Nelson. Submit your own question here.

Q: I have a Lowrance LCX-104C and fish off the Straits of Juan de Fuca. While out trolling for salmon, we have never marked any fish on the screen, but we are catching fish. Is this normal not to mark salmon or is there a specific setting on the fish finder? – Lualhati

A: Without a hands-on examination of your Lowrance, I would say that – perhaps – you have your sensitivity setting too low, or, your transducer not mounted correctly. You do have to remember, the signal sent down by the transducer is essentially cone-shaped. So, if the fish is outside the cone, you may still catch it but not see it on your screen. However, if you’re seeing no fish at all, you have a different problem.

Q: Thank you for this opportunity to ask a question as I have exhaustively perused the web for an answer but come up empty. My wife and I were salmon fishing in the central channel abeam the “shipwreck” on October 25 when my wife caught a very large salmon – at least 14 pounds! This salmon was different. It seemed well into its spawning phase with distinct coloration (dark body, olive green head and tail, red mottling on the sides) and had large canines. After researching the descriptions provided by WDFW, indications are that this was a large spawning Coho. However, I have always understood that these physical changes occur only after entering brackish and fresh water. Do salmon exhibit these characteristics while still clearly in the saltwater of Puget Sound? We returned the fish back to the water not knowing if it was a viable and legal “keeper.” Thank you – Gary

A: The physical changes you describe can take place in both salt and freshwater. It depends on how far the salmon is going up-stream to spawn. For example, salmon in Elliot Bay often take on dark, protective coloring before entering the Duwamish River. Salmon entering the Columbia River, and traveling hundreds of miles up-stream, stay bright until close to their spawning destination. The salmon you caught may have been a lower river spawner.

Q: Will kings “not” come up the rivers to spawn if the water temps are in the 65-70deg range,or will nature eventually force them upstream? – Bob

A: Yes, that does delay the spawning trip for Chinook. But, eventually, they will come in to spawn.

Q: When is a good time of year for Sockeye in Lake Washington? – Mike

A: July and August are the best months for sockeye in Lake Washington. However, it hasn’t been open for a season for many years now. As long as gillnets and purse seiners catcher Cedar River sockeye in the San Juans, in and below the locks, in the fish ladder at the locks, and in Lake Union, I doubt you will see a sockeye season for sportsmen. Too bad. That fishery sold more fishing licenses and tackle than the rest of our fisheries in Washington put together.

Tom Nelson

Tom Nelson is the publisher of salmonuniversity.com. Known throughout the Pacific Northwest as the “Dean of Saltwater Fishing,” he has helped develop and test tackle and gear for Scotty, Pro-Troll and Silver Horde, is a regular speaker at area sports shows, has taught more than 5,000 students how to fish during his classes at western Washington community colleges, and is the co-founder of the Puget Sound Anglers.