Sea Lice in BC

Dale Dennis

Formally Double-D
This searun lice phenomenon has been eating at me for several years. As I see it brought up more and on this forum it eats at me more. I thought I would do some research and found this site regarding some pink salmon runs in BC that are in serious trouble because of infestations of lice on juvenile pinks.

Some are blaming the fish farming and I don't think it is what we are experiencing here but it does concern me.

I really think this parasite that is attacking our beloved searun needs some attention.
The lice they are experiencing in BC is of a different type but it is still a parasite that is in epidemic porportions as we are experiencing here in the sound.
Although I have witnessed lice on cutt juveniles at approximatly 8" (in the salt) I think the advantage that searuns may have over BC pink salmon juveniles is that they leave there natal streams at a much larger size.

I agree with Les, you didn't see this years ago, something has changed. I started seeing the lice approximately 10 years ago in the South Hood Canal and I have fished searuns in the Canal since the early 60's. Now it is prevalent in the North Sound (as far north as Skagit Bay) for at least the last 6 to 7 years that I can recall.

I appologize in advance if this link doesn't work.
Check with the DFO in British Columbia or WDFW. They usually answer questions like yours and have some scientific data available, although not a whole lot on coastal cutthroat. Perhaps Curt Kraemer can clarify your question if he sees the post.
Good Fishing,
Les Johnson

Bob Triggs

Stop Killing Wild Steelhead!
Another researcher from B.C., Dr Volpe, has presented papers and been published on sea lice up there. He was with Oceans Canada and B.C. Fisheries, now he is at Univ Alberta, I believe in Calgary. Appearantly they did not like Dr Volpe saying bad things about the B.C. Fish Farming industry and it's impacts upon the Archipellago waters and fish.


Active Member
Double-D -
First lets be clear the critter that we are seeing on the sea-run cutthroat is not same one as the one causing problems around the net pens. While there are several species of Caliges (sea-lice) none of them appear to be what we see on the cutts. I don't know what that critter is and while it is convenient to call them sea-lice they probably are not. If we knew more about what sort of critter they are we could learn/speculate about what appears to be causing higher abundances.

The first time I fished Hood Canal for cutthroat (1974) I caught one with those critters on it though not at any kinds of the numbers we now see on them. Why they are more abundant (if they are)? and what changes in the environment caused the increase are unknown. It could be a simple as having more cutthroat in the population allow for the development of higher parastie numbers to the very complex. I supect the answer is complex (changes in the invertebrate community, prey/predator relations and stream flows changes come to immediate mind).

Perhaps the more important question is whether these parasites are causing significant problems to the cutthroat populations. With the ability of the fish to shed these parasites by ducking into freshwater they be more of an inconvenience than life threating.

Has anyone seen any evidence of skinny or dying cutthroat with heavy infestations?

Tight lines

Dale Dennis

Formally Double-D
I totally agree Curt, it is not the same critter or scenario they are experiencing in BC. I just wanted to throuw out a similar situation with lice (or?) infestation. So far, there has been no recorded harm to searun that I know of. However, I do think that there are extreme changes taking place and should be watched closely.

I could have been a little clearer in my food throwing for thought. Not a red flag, just something we should definitely monitor.

I might add, don't anyone even try to remove these, they do fall of when they enter fresh water.


not bad for a yankee
I actually have had a chance to meet Dr. Volpe, he is now working at my university (University of Victoria on Vancouver island). Between he and Alexandra Morton there have compiled enough research to really provide solid evidence on how profoundly the burgeoning salmon aquaculture industry has become. Their area of study is specific to pink and chum salmon smolt, but it seems likely that their findings will be relevant to young steelhead, searun cuts, dollies, and other salmon. I've had friends that have worked at salmon farms and from what they've told me i will never eat farm raised salmon again.


not bad for a yankee
Also, as a BC resident, i can tell you that the DFO is a sham. For anyone that wants clear cut evidence, read Otto Langer's letter to the premier of BC, heads of the DFO, and Prime Minister. As a former DFO employee, Langer was told to keep silent on his scientific evidence that proved the dangers of various industry. Industry lobbyists pressured members of the DFO to encourage their scientists not to report their findings if they stood in the way of salmon farms, logging, mining, etc.
Smalma said:
Double-D -

Has anyone seen any evidence of skinny or dying cutthroat with heavy infestations?

Curt - I'm not sure if they died but over the last 2 - 3 seasons I've caught increasing numbers of searuns at Kayak Point that are just loaded with these parasites. In several cases (6 - 7 fish) they had that "snakey" (big head and thin body) look that fish get when they are undernourished or ill.

On a typical fish in the early '90s I would find an occasional copepod or two but recently this number has increased to a dozen or so and on occasion even more. Hope there is no significance to this but as I said, some of those fish looked pretty sick to me.


Active Member
Tom -
Thanks for the obserations - where those "skinny" fish spring fish (April/May) or summer fish (July/August)? Wondering whether they were kelts that haven't recovered.

It is pretty clear that the parasites are increasing. With the regulation changes on the Stillaguamish (all CnR with selective gear rules during the summer) I would have expected to see a larger portion of its sea-runs being older fish by now. My experience this past fall is that is not the case and I have to wonder what has prevent that from occurring - certainly these parasites may be a possible "smoking gun".

I wonder if folks are seeing this increase in other areas - so far Hood Canal and Port Susan. I haven't seen them in any numbers in Skagit Bay though I haven't sampled many fish there lately (sounds like a project for this summer - darn will have to go catch some). What has been others observations in north Sound, Straits, South Sound?

Maybe if we can define where the problem is the worst we can gain some insights to the underlying causes.

Tight lines


FFing and VWs...Bugs & Bugs
Over the past few years I've not noticed a marked increase in the amount/presence of sea lice on SRCs in the salt around Bremerton, but them I don't seem to hook that many. :)

Bob Triggs

Stop Killing Wild Steelhead!
Smalma, I have seen two fish- Sea Run Cutts- in the past five plus years, on Marrowstone Island, that were very heavily infested with Sea Lice, (of many developing sizes), and both fish looked very bad off. They were weak to hand and their slime layer seemed almost gone.

I do see some fish each year that are heavily infested, but otherwise are robust and dont appear to be wasting or fatigued.

Most of the Cutts we catch in this area seem healthy and robust, a broad range of sizes and color phases.

I have fished SRC in the South Sound for quite awhile and not noticed sea lice to be very prevalent on SRC at the locations that I fish. Ocassionally a SRC might have numerous sea lice but usually there are none or just a few of these criters on them. The SRC in the South Sound appear to be fat and happy in comparison to fish in the southern part of Hood Canal.

I keep a detailed fishing journal so I am going to start noting the absence or abundence of sea lice on SRC to see if there are any trends or need for concern.


Dale Dennis

Formally Double-D
I will also be keeping a detailed journal on the cutts and the parasites I find. It will include where, date, number searuns with and without lice, and approximate size (no physical measuring) and # of lice. This needs to be accomplished with the least amount of handling.
I will typically start fishing searuns in the north sound around the 4th of July.


Active Member
It is starting to sound like the worst of the "lice" problems here in Puget Sound is in Hood Canal and Port Susan. Both areas have poor water qualtiy and seem to have gotten worst in recent years. If we keep our collective eyes open we may be able to narrowly define the extend of the problem or at least where it is the most serious.

Double D's idea of keeping notes sounds good - in addtion to the information he suggested

For size just group the fish
Smolt - less than 9"
Subadult - 9 to 12"
adult - over 12"
Old timer - over 16"

Condition of the fish -
Robust -

Other ideas?
Tight lines

Did I read you correctly that the organism we're talking about is some kind of unknown critter?(!) Or do you just mean it is not the same type of Copepod as the animals we commonly call sea lice, and we on the board don't know what they are? And just to make sure I'm on the right page, we are talking about the largish (dime to nickel sized) disk-ish shaped parasites (the ones I've seen were a darkish smoky color) that can be thick enough on cutthroat backs as to make them appear lumpy; right?

If they are unknown, that seems pretty remarkable, and figuring out what they are would appear to be a good place to start any serious monitoring effort. And if it is just us, it would be nice to find out (I've always just assumed they were some species of big "sea lice"). One question that occurs to me is whether these organisms occur with any other species other than coastal cutthroat. I've never seen one on any other fish, has anyone else?

It seems to me there are a couple good reasons for at least the beginning of concern. First the phenomenon appears to be increasing in frequency and intensity, at least in some fairly broad locations. Actually first might be (if it's the case), "we don't even know what the damned things are!" I mean my God, I saw "War of the Worlds"; what if it's the stealth vanguard of an alien invasion?!

Where was I? Oh yeah; second, doesn’t WDFW acknowledge that the status of most PS cutthroat populations is unknown? From an angler’s perspective, the fishing seems reasonably good so we figure things are OK, but apparently we really don’t know much about long term (or even short term) trends in population abundance, diversity, or distribution. That situation should always encourage caution and concern, particularly in regard to any perceived threat, like a potential parasite infestation.

Your concern about not seeing more and/or bigger fish in the Stilly is interesting. Some studies have suggested that adfluvial cutthroat in Lake Washington (which might be expected to demonstrate similar life-strategies and ecologies as sea-run cutthroat in sheltered Puget Sound waters) have increased in abundance and distribution as they have exploited niches abandoned by declining populations of coho and Kokanee. It is my understanding (admittedly limited) that sea run cutts show relatively low fidelity to any particular natal stream. That would indicate an evolutionary tendency toward probing and exploiting new habitat opportunities, wouldn’t it? Many species sympatric with coastal cutthroat in tributaries to Puget Sound have experienced declines similar in scale to the declines of coho and kokanee in Lake Washington. Why are we seeing significant expansion of cutthroat populations in Lake Washington but not Puget Sound?

Of course the rub there is that we probably don’t know whether or not it is happening in Puget Sound; my impression is that serious research on PS cutthroat populations has been lacking, though that is apparently changing somewhat.

But let’s pretend for a minute that it’s not happening. Available habitat niches have expanded; fishing regulations have gotten more conservative, particularly in most of the smaller tributaries; habitat management, while far from perfect, has certainly gotten better over the last say 25 years. Yet something seems to be not quite right with PS cutthroat. Maybe it is the parasites, whatever they are. Or maybe they are just a symptom of some other underlying problem. Maybe the parasite population hasn’t really “expanded” but the cutthroat population is experiencing some type of stress or combination of stresses that make it more vulnerable to infestation. For instance, while angling regulations have gotten more conservative, angling pressure in the salt has risen, especially in the last few years; maybe angling related mortalities have stayed the same or even increased.

The more you think about it the more complicated it becomes, and you are right when you say it’s too early to say what the problem is or even if there is a problem. But it certainly seems like something is going on. Increases in parasite infestations almost always indicate something out of whack. Parasites have no “interest” in wiping out host populations; that is clearly an evolutionary dead end.

But I do want to know if these horrible little things really are unknown. If they are, I’m going to start lining my fishing hat with tin foil.