Does late summer water temperatures affect sea-run cutthroat fishing?

I fish for sea-run cutthroat mainly in Marine Area 13 which contains numerous shallow inlets particularly in the southern part. These shallow inlets in combination with extreme mid-day low tides and hot air temperatures in July through mid Sept. make the southern part of Marine Area 13 prone to increased water temperatures. Over many years I have noticed that sea-run cutthroat fishing normally slows down mid July through mid Sept. almost every year. I have always wondered if the sea-run cutthroat were just too scattered.

I have a GPS/fish finder on my boat. The instrument gives water temperature reading on the screen. I never have paid attention to the water temperature readings. However, this past Aug./mid Sept. I happened to notice water temperature reading were consistently 62.9 degrees F. or slightly higher. The GPS/fish finder water temperature readings were within 0.1 degrees F. of an accurate digital water temperature instrument. It is my understanding that cutthroat in freshwater prefer water temperatures of less than 65 degrees F. due to stress/health issues. IMHO when Puget Sound water temperatures approach 65 degrees F. sea-run cutthroat would probably seek cooler water which can be found in deeper water away from near shore areas. I normally fish water which is 6 to 8 ft. or less deep. In late Aug./early Sept. when I started fishing deeper water(12 to 15 ft.), more sea-run cutthroat were hooked vs. near shore areas()6 to 8 ft. or less).

If Puget Sound water temperatures approach 65 degrees F. and would cause stress/health issues, it may be advisable to give the sea-run cutthroat a "break" during that period. An option is to fish for warm water species in fresh water which can be outstanding during that period.

Maybe Kurt Kramer or other fish biologists could express their opinions on the affects of higher water temperatures in late Summer on sea-run cutthroat particularly in the southern part of Marine Area 13.



Active Member
Roger -
As always a great question and insights into the world of cutthroat fishing.

First I know very little about the conditions in South Sound or its cutthroat but will offer some general thoughts. The warming of the sound's surface water taht you area seeing is likely the result of two different processes. The first is that with the longer days and stable weather patterns it is come to see solar warming of the surface waters of large bodies of water. In the case of Puget Sound while the surface water warms there remains vast amounts of cooler water in depths that is constantly being mixed with that surface water via the mixing from wind and current actions. The result is that warm layer is relatively shallow/thin. That mixing is also why for most of the sound those temperatures are in the 60s instread of the 70s or 80s seen in inland lakes.

The second process is much different and of more concern. In shallow bays following low tides that expose vast areas of sand/mud and on the flood of the tide the solar heating of that substrate is transfer to the shallow water as it flows into the bay. In this case temperatures can get suprising high (this happens every year on Port Susan near the mouth of the Stillaguamish where surface temperatures often reach well into the 70s).

However the real question(s) is what does that mean for the cutthroat and the fishing for them. First temperatures in the low 60s are not a big issue for the cutthroat and they will easily hold is slightly cooler waters darting into the warmer water to grab a snack. However in the situation where bays (large or small) have high temperatures the warm water will influence the cutthroat. This would especially be true on an ebbying tide. As the bay drains there will be a large plume of warm water leaving bay that would naturally push the cutthroat down bay to cooler water (as a result spots that normally fish well on the ebb would be essentially devoid of cutts).

I thnk of more interest is the bait fish behavior at that time of year and how the cutthroat respond to those potential changes. First as the bait fish grow it is normal for them to move into deeper water and off shore. Secondily as with the shallow bays the shoreline margins will heat up some on the flooding tide which would also tend to push the forage fish deeper. That time of year areas where strong currents push bait into the shallows may be more productive than areas where eddying water formly collected the small baitfish.

Finally August and September often has some pretty stable weather producing some wonderful conditions for fishing. However in the glass-like water conditions that we often find that time of year the cutthroat can become pretty skittish in shallow water spots.

Don't know if any of the above makes sense or applies to your fishing but I throw it out or consideration. If I had "pet" shallow spots that time of year I would focus my efforts to flood tides and during periods with cloud cover/fog or good chop.



"Chasing Riseforms"
Some time ago I decided not to fish much for sea run cutthroat in the hot summertime. Generally, where I fish is not far from estuaries, but not always. When the tide goes out on the mud flat areas and the sun has a chance to "bake" those, then the water is quite warm when the tide rolls back in. The nearby beaches warm too with the tide movement. I don't think any trout in his right mind is going to hang in those shallow areas of warm water and would seek cooler deeper water. For a beach fisherman like me, the fishing does slow down unless you can get your fly in that deeper water, and, move away from those shallow estuary areas. So, I found myself doing a little lake or stream fishing that time of year. For those with a boat like you Roger, you can get to those deeper waters easier.

Dale Dennis

Formally Double-D
Hi guys, it’s good to be able to get back on the forum, always enjoy your insights on salty cutts.
I will have to admit I have not paid too much attention to water temps here in the North Sound as compared to the South I don’t think the water temps change all that much here. It has always been my contention that the forage will dictate where and when they will be concentrated.
When I could get out the summer and fall turned out to be a banner year for quantity and quality.
According to my salt journal one of my better days was 8th of October fishing an incoming noon high. The morning started out slow with very few showing but within two hours of the high I began noticing searuns working a section much closer to the beach than usual (with in 6 to 20ft of dry land) 2 to 5ft of water. As I moved in it was apparent why they were there I had large schools of bait which looked to be smelt under my boat I could actually see cutts slashing through the bait below me.
I moved out far enough to get a 40 to 50ft casts in this area. My first cast produced a healthy 16” and for more than two hours it was the same with the largest approaching 17”.
The top water action has been superb especially during the lower end of the tide along eel grass beds.

Your posts and replies are always knowledgeable/informative! Your reply has given me some "food" for thought. Wow that is surprising that water temperatures in Port Susan area often are above 70 degrees F.


Today Doug Rose send me his thoughts about summer water temperatures in the northern part of Hood Canal. It is very informative and should be of interest to you since it is your saltwater "home water". I'll post a his thoughts in a new reply.


Good to hear that you have had a superb summer fishing for sea-run cutthroat up your way. Down my way it was an average summer fishing for sea-run cutthroat with nothing to get excited about after mid June. Before that it was pretty good.

How is your new job going in the fly fishing department of the new Cabela's up your way?

Here a message that Doug Rose sent me today concerning summer water temperature around Port Townsend and northern part of Hood Canal.


"Hi Roger. A friend of mine told me about your question on WFF about water temperatures and cutthroat. It has been my experience wade fishing in Hood Canal that the water temperature often gets too warm, at least within casting range of the beach, in late summer and early fall. Just this summer, I was doing a photo shoot with the Northwest Fly Fishing guys on Dabab Bay for an article I wrote. We were supposed to get out in spring but we never actually made it until late Aug. I told them that the water was probably too warm -- it had been 65 the week before--but we went out anyway. There was no sign of bait or cutts and I said, "let's go up to Indian Island," because the water is always significantly cooler there as a result of mixing from the Strait. We got a number of nice fish. Also, a few years ago, Joe Uhlman spent about a week fishing the northern canal, including a day with me, and we did very poorly. Later, we found out from an oysterman friend of ours that the water was nearly 70 degrees 10 feet down. I definitely think the cutthroat in the canal head to deeper water when the nearshore is warm. By the way, we changed the focus of that article from "Northern Hood Canal" to "Rain shadow Cutthroat" to include the area to the north. --ps--I meant to add that there are submarine sills at the mouth of the canal which inhibit mixing and that may also help to boost late summer water temperatures. Doug"

Rich Schager

You should have been here yesterday...
"Over many years I have noticed that sea-run cutthroat fishing normally slows down mid July through mid Sept. almost every year. I have always wondered if the sea-run cutthroat were just too scattered."


I'm also located in the South Sound. Where I fish, it is just the opposite. "Good" cutthroat fishing is only from mid-July through mid-September (ends when the salmon beach seining starts). And contrary to the SRC standard 6-8 feet or less of water, almost all fish are caught in 8-15 feet of water. Out of the 10 or so fish in the 16"-20" range caught this summer, every one was caught in deeper 8-12 ft water. Don't know where these fish come from. There are no spawning creeks nearby, and the fish just seem to wander across open water to get here for a couple months and then probably head towards where-ever home is again...

Rich Schager.

Dale Dennis

Formally Double-D
Its going well Roger but it does keep me occupied to the point of not getting out as much as I would like, including tying. If you get up this way stop in and say hi and that goes for all.

I used to fish the South end of the Canal exclusively for many years but when the issue of oxygen levels and warming waters became severe I decided to let up and concentrate more of my fishing to the north.
It was so bad my in-laws that have lived on the Canal sense the 50s said it was the worst they had ever experienced and almost completely lost a crab fishery that is now returning.