Discussion in 'Saltwater' started by SilverFly, Nov 12, 2015.
Just need to connect the dots!
Watching the SST charts over the last several years it's interesting to see the same patterns develop. Especially the "tuna highway" or ridge of warm water that develops most years off the Oregon/Washington coast. I don't pretend to understand the dynamics of what's actually going on with ocean currents , up-welling, etc... It's just fascinating how the water 20-30 miles off our coast is comparable to nearshore southern California or northern Baja. OTOH, virtually the entire coast of California north of Santa Barbara is cold water up to a hundred or more miles out.
I'd also love to know why SoCal gets Bluefin tuna and we get albacore in nearly identical water conditions. Fish like this BFT caught 2 days ago. Estimated weight 200lbs.
I can't speak to your last question contrasting bluefin vs. albacore.
But your first question is linked to the intensity of upwelling off California vs. Washington (see https://www.nwfsc.noaa.gov/research/divisions/fe/estuarine/oeip/db-coastal-upwelling-index.cfm). Because of more consistent winds from the north (more hours/days and higher wind speeds), California tends to have a higher upwelling index (and input of cold, nutrient-rich water) over the year than does Washington. During periods of upwelling, warm, nutrient-depleted water from along the coast is pushed offshore by Eckman transport and is replaced with colder, nutrient-rich water from deeper depths. In winter and early spring, Washington often has winds from the south which leads to downwelling - pushing warm, nutrient-poor water from offshore onto the coast. The downwelling occurs when you have a negative "upwelling index".
You can get some feel for the regional variation in these values at this site: https://www.pfeg.noaa.gov/products/...25W+48N&prod=Upwelling+Index&Submit=Show+Plot.
For example, here are the upwelling index values for May and June 2017 for Washington (48oN). Values above zero would indicate upwelling and values below zero would indicate downwelling. There was a big upwelling spike on May 23rd and several downwelling periods in early June.
If you look at the index values for 36oN (Monterey, CA), you can see that this area experienced no downwelling periods, but primarily experienced strong upwelling in both May and June, more upwelling and stronger upwelling. And the upwelling appears to be intensified at the various rocky points along the California coast.
When I lived in Santa Barbara, I really do not remember hearing about folks fishing for tuna off the central and northern California coast, mostly just off San Diego. I would speculate that if you were out of Morro Bay or Monterey, your travel time would be prohibitively expensive of time and fuel to reach offshore waters that are warm enough for tuna. Because San Diego experiences far less upwelling, fishing for tuna would be a more reasonable proposition because of warmer water closer to the coast. Off our coast, our most intense upwelling occurs in the summer, especially July and August, but it is still far less intense than California (or even central Baja).
That offshore transition between green coastal water (high primary production, more zooplankton, more baitfish, cooler) and clear offshore waters (low primary production, less zooplankton, fewer baitfish, warmer) is the money area often for tuna fishing.
Ok guys I'm heading out for albacore next month out of OR. I went out 2 years ago but did not have the right line or flys. I ended up using a gear rod, but would love to put a check mark behind albacore. I have a Xi3 13wt, and a 500 grain Rio Leviathan 500 gr, which I can at least cast with the Xi3, which is more then I can say about my 12wt backup rod. So I'm hopeing I have my line problem solved but I'm still looking for some fly pattern ideas. Anyone willing to share a few known patterns? PM would be great.
Al, I'd suggest a variety of standard baitfish patterns from 2.5"- 5" or so. Some long skinny patterns to represent Saurie, think sand lance profile, and some brightly colored attractor style patterns.
Silverfly's anchovy pattern is easily the best looking anchovy fly I've seen and I would look to copy that. He has a SBS.
Most of all don't over think it. Nothing tops live anchovies when sitting on a good school, but next to that we catch more fish on these than anything else. Trolled at six knots just under the surface the fish go bonkers for them. The biggest key IMO is finding a school that wants to play.
I love this forum. Where else can you post a question based in ridiculously unrealistic fantasizing about big fish, and learn about something like "Ekman Transport"?
I ran across an interesting paper on drift net bycatch of ocean sunfish and bluefin tuna from 1990 through 2011.
Of particular interest to a PNW fly fisher obsessed with BFT are the catch distributions by month. No surprise that September and October would appear to be the most likely time to encounter BFT off our coast. Also some useful probability stats based on water temperature and cholorphyll concentration. Both being closely observed factors in albacore fishing. Even more tantalizing when considering that this study ended 3 years before the massive resurgence of bluefin tuna fishing in SoCal. Given the incredible numbers of fish down there, it may not be that unrealistic to expect increased incidents of spoolings and destroyed albacore gear later this summer.
This is getting me excited!
Whatever you do, don't start watching videos of SoCal tuna fishing! If you do, just keep in mind that talk of those fish showing up here in numbers is mostly wild speculation, with a bit of science to back it up.
I could happen though, and I want to be ready if it does. The PNW is very much part of their natural range. In fact, it's probably an accurate statement to say their relative absence here is very un-natural.
For me it's the possibility of what might be encountered in the open ocean thats exciting.
So I got sick of reading about the amazing BFT fishing in SoCal and asked on a board down there if anyone is fly fishing.
At least a couple guys are giving it a shot:
Came across this article on using sonar to find tuna: use the lower frequency because it has a much wider cone and will show more returns from fast moving, widely spaced fish that don't have swim bladders.
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We've been doing that for years. The NW has so many varied fisheries...that you really need to have a good handle on your electronics if you don't want to flail around blindly.
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I'd be interested to learn more about tuning sonar to detect changes in the water column that the fish might be orienting too. Things like "Mixed Layer" depth, thermoclines, and the Deep Scattering Layer. The latter could be important when fishing early, late or especially at night.
I knew the 50kHz was better at deeper waters because of less loss but thought the higher resolution 200kHz would always be better in less than 200ft. But that cone factor is more important than resolution of detail for fast movers. Glad to have a scientific reason to chose 50kHz rather than just it works.
Down scan on tarpon is amazing with that big, suspended target.
Not my pic but I have seen the same thing on my unit so I know it's not a photoshop.