|The oceanographic picture this season is the strangest I’ve ever seen or heard of. Northern Bight Sea Surface Temperatures (SST) and dynamics are pretty normal for this time of year, cold with colder upwelling regularly during frequent westerly windy weather, a classic spring, like we haven’t seen in several seasons. But south of the Channel Islands, it’s totally El Niño. No matter how hard the wind blows in the Channel Islands, only a modest fraction makes it into the San Clemente Basin — that broad body of water between San Clemente Island and the beach, extending south into Mexico. When it does, places like the Coronado Islands are bulletproof — SSTs hold solid at 62 degrees, creating a spread of more than 10 degrees between the northern sector and southern Bight.
ALBACORE TEND TO follow the 61-degree contour across the Pacific in clean oceanic waters, to just offshore of where it intersects the cool coastal band of green water mid-June and follow northward there as the season progresses and waters warm. On April 12, 2017, 61 degrees is in the green.
“Normally” this spread is 4 degrees and less, with the north seeing consistent 56-degree late April-early May SSTs with an occasional dip to 53 or so, and the Coronados hovering near 59 with an occasional dip to 56 or so, in sync with windy weather and the northern sector. Friday the Gaviota Coast showed a chilly 52 degrees, as the west winds have howled all night. Off La Jolla, SSTs showed 62-plus, also having been exposed to the post-front passage windy weather. A few days prior saw temps near 65 in some southern places. Back in the day, out on the San Diego albacore grounds, 65 was considered pretty hot water, even in late August.
By way of getting on the same page, the way I understand the dynamics, is spring northwesterly winds drive coastal surface waters and waters along the edge of the wind-line, offshore, through a complex process of wind stress and coriolis effect. Cold underlying coastal waters are pulled toward the surface.
Normally there is an abrupt thermocline not too far down, between 30 and 70 feet or so, one which most seasons sits around 40 or 50 in our coastal waters. Cooler waters below tend to have more phyotoplankton producing nutrients.
When the wind blows, these cold waters are drawn up and mix into the surface water, temps plummet, a few days later the water turns green — even brown with phytoplankton as the nutrient-laden waters are exposed to the full phyte-growing force of the sun. Later in the spring season, gobs of phyte-eating zooplankton fill the upper waters, a myriad of little wiggly things and such. Anchovies and sardines, squid and now red crabs grow fat on that.
CHLOROPHYLL A IMAGES show where green water was last Saturday, red being the greenest of all. New cold upwelling comes up gin clear at first but nutrient laden. Notice there is no green to the new cold water, but previously upwelled water recently pushed aside is loaded, showing red. Offshore, well beyond the coastal green plume it’s warm and blue.
Come summer, the coastal water clears and baitfish find themselves foraging out into clean water — being chased down by game fish which come swarming in, sometimes from clear across the Pacific. They come to take advantage of the baitfish-squid-red crab bonanza. That’s the classic dynamic as I understand it.
The first indication we got something really weird was up winter before last, was when spring winds came and waters all along the coast only cooled for a day or so, if at all. And the windy season faded early. Throughout the summer, the Central Coast landings lost hardly a day due to windy weather, virtually unheard of in those parts.
Then it was “The Blob” and then finally an admitted full-on El Niño. Then, La Niña was forecast last fall. Heavy rain which hadn’t come with El Niño as was predicted, did come with La Niña — rather unexpectedly. And now El Niño again seems to be knocking on our doorstep and climate forecasters are looking rather like wand-less wizards scratching their heads. Meanwhile, computer weather models seem to be rocking it regards to the weekly forecasts, nonetheless.
Now, as I look at the SST plots locally and pan Pacific, I see the strangest set-up ever. Drawing an east-west line along the Channel Islands, it looks like a “normal” season north — colder waters than we’ve seen in a long while, with northern mid-Pacific waters cooler than they have been in several years.
In more recent seasons, that band of albacore carrying waters between 59 and 63 degrees pointed straight at southern Washington state, and although there were cool waters running southward from there along the coast, the straight shot delivered the fish right to where they have been every season in the past two decades. The heart of that fishery has been between northern California and Washington. But today it points — right at the SoCal Bight.
SEA SURFACE TEMPERATURES last Saturday along the upper Baja Coast show the effects of upwelling cold waters replacing surface waters as they were “advected offshore” by Friday’s down-coast winds.
Yet, just a hundred miles south of the Channel Islands it looks solidly like El Niño is returning — deep thermoclines windy weather can’t seem to dredge cold waters up from. There’s an inexplicable attenuation of the 30- and 40-knot-plus spring gales of the western Santa Barbara Channel and outer waters. The heavy winds drop to mid- and low-20s as they pass anywhere south of San Clemente Island. SSTs there are solidly 4 or more degrees warmer than they should be, and seemingly unfazed by windy weather when it does come.
What does it all mean for the coming fishing season? Well, we seem not to be missing out on Channel Islands squid-related opportunities. Yet Catalina Island yellowtail counts have already surpassed 200 fish some trips. Offshore, the big bluefin tuna are already back. The San Diego fleet is already in offshore fishing mode and the offshore bite has already drifted within 3/4-day zone. Having 3/4-day offshore pelagics is something that rarely happened at all in “normal” seasons, and certainly not in early April.
We’ll have to see, but I’m getting ready for anything — dropper looping live squid for seabass to winging poppers at foaming 100-plus tuna with the biggest gear I can still make a decent toss with. Plus, I’ll be making sure I bring an 8-ounce torpedo and a couple of 4/0 squid-strip hooks on every trip, just in case that’s what it turns to be all about.
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Merit McCrea is saltwater editor for Western Outdoor News. A veteran Southern California party boat captain, he also works as a marine research scientist with the Love Lab at the University of California at Santa Barbara’s Marine Science Institute. He can be reached at: firstname.lastname@example.org.