11 October 2015

11 October 2015

Hello Seabirders,

This is the Buena Vista Audubon and Grande pelagic trip report for Sunday October 11, 2015. We greeted daylight with clear skies and an absolutely crazy mass of fisherman coming and going at Point Loma Sportfishing Landing on San Diego Bay. We felt a little lost in the crowds, but as boats departed and fisherman and fisherwomen cleared out, we gathered, got a little orientation, and 48 passengers and seven leaders boarded our old standby and friend Grande. Grande had just come in from a day and a half fishing trip, unloaded fish and fisherman, got a quick scrub down, and we were ready to cut loose and head to sea. This is a fast turnaround in what has to be one of the most epic fishing seasons in many years – perhaps a lifetime. That was the reason for the craziness around the landing this morning.

Leaders for this trip were Mark Billings, Greg Gillson, Peter Ginsburg, Paul Lehman, Guy McCaskie, Bruce Rideout and myself. We also had a group of a half dozen San Diego regulars who always provide extra eyes and assistance, and deserve our thanks. They certainly make these trips a little easier. We pushed out of the commercial basin into the main shipping channel and south to the tip of Point Loma. Escorted the whole way by large numbers of HEERMANN’S GULLS, with the occasional flyby ELEGANT TERNS, or ROYAL TERNS. The former nearing their departure date, the latter increasing in numbers slightly as they are a fairly common wintering bird here.

The channel buoys just south of Ballast Point and all the way down to the SD (Whistle) Buoy three miles out had much of the expected sea lions, cormorants, and gulls. Today many of the buoys were decorated with BROWN BOOBIES. I saw two buoys with six, another with four, one with two, and so on. Throw in several more boobies flying around the immediate area. I think I counted nine inside Point Loma and another dozen or more just off the Point. We once considered BROWN BOOBY rare here, not so now. Thirty-two for the day is not any big deal. Certainly one of the more amazing changes in avian distribution!
Leaving Point Loma behind we headed southwest toward the inner edge of the Nine Mile Bank, and the Mexican Border. This track took us through much of the expected inshore species. San Diego’s signature inshore seabird is BLACK-VENTED SHEARWATER. We got nice looks at these guys at all distances as a few came in to the chummed gull flock in the stern. Paul on the P.A. pointed out their characteristics compared to other expected shearwaters.

I find it interesting that normally we would be expecting the return of BLACK-VENTED SHEARWATER in the late summer and early fall, with number steadily increasing into winter. This year they arrived back here in numbers in June and July, when normally nearly absent. Their numbers have actually been in sharp decline locally this fall. Reports of BLACK-VENTED SHEARWATER from as far away as coastal N. California, Oregon, and Washington may explain where they have gone – more evidence of displacement cause by historically high sea surface temperatures in the northeastern Pacific. Not so glamorously called “The BLOB”.

This inshore area also turned up good numbers of phalaropes. The overwhelming majority were RED-NECKED PHALAROPES, with a few larger, whiter, RED PHALAROPES scattered about. Both species of phalaropes gather around the slick-lines from tidal outflow from San Diego Bay. This is an area of water mixing and churning that often has the coolest water and most nutrients from down in the water column. Today the sea surface temperature (SST) here was 72 degrees F. I’ll talk more about SST’s later in this report. This area had a few CASSIN”S AUKLETS, with more further offshore. This species is an enigma to me. We once thought, with reason, that low CASSIN”S AUKLET’S numbers were an indicator of lower ocean productivity. The productivity being lower due to increased sea surface temperatures. Yet CASSIN’S AUKLET’S numbers remain strong this summer, and CASSIN’S AUKLETS were among the more abundant species seen today, with 150. Though most of this boat-shy species were seen at a distance.

This inshore area had a few species that were a bit out of place: a COMMON LOON, two WESTERN GREBES, a flyby group of eight WESTERN SANDPIPERS, a POMARINE JAEGER, a SABINE’S GULL, and a couple of “not so common” COMMON TERNS. The last three species were seen in greater numbers further offshore. We also had a small passerine do a quick pass of the boat, one of three for the day, and none I.D.’d beyond guesses as to warbler type or sparrow type.

Up on the Nine Mile Bank, we found an EARED GREBE – an odd but somewhat regular “seabird”. BLACK STORM-PETRELS were in small numbers, most at a distance, and not well seen until later in the day. We also ran up on two HUMPBACK WHALES here. Those on the bow got a good close look.
As we passed over the drop-off on the western edge of the Nine Mile Bank we picked up a second PINK-FOOTED SHEARWATER in the wake, and several folks rushed to get a gentleman off the bow and back to the stern, as he needed that species for number 600. Hats off to him for a well-earned milestone.

We also spooked-out many CALIFORNIA FLYINGFISH in this stretch. I saw a lot of photographers trying to get these crazy things in focus, and some succeeded. They certainly had plenty of targets, as twos, threes, fours, and fives popped out at a time – some traveling a hundred yards or more. This turned out to be a good diversion as the San Diego Trough, notoriously for being quiet, was living up to its reputation today. One eBird survey hour had 42 birds: 2 CALIFORNIA GULLS, 20 WESTERN GULLS (all chummed in ), 2 BLACK STORM-PETRELS, 18 CASSIN’S AUKLETS. Yep that’s all for One Hour! The midday heat was just enough to create a nice naptime for some, without a much being missed.

The Thirty Mile Bank had a little more life, but scary little. We did pick up another NORTHERN FULMAR or two, a single PINK-FOOTED SHEARWATER, a rather nice looking SOOTY SHEARWATER, a scant few more BLACK STORM-PETRELS, a couple of POMARINE JAEGERS, a distant look at a LONG-TAILED JAEGER, more CASSIN’S AUKLETS, and two more SABINE’S GULLS. We were in need of a big hit out here, and it wasn’t happening. We kept working north until we started to get just a little more storm-petrel action; at first just two or three, then a half dozen, then another scattered half dozen. Then eagle-eyed Paul had them. The RAFT!! Fully a mile off and outside our normal search area, this was in Los Angeles County waters, as we were closer to San Clemente Is. than to mainland San Diego (La Jolla).

We seemed to take “forever” to get up to the raft (actually two rafts, a larger and a smaller one), but instantly we knew we’d hit the LEAST STORM-PETREL mother-lode. Photos may give us a little better ratio, but LEAST STORM-PETRELS clearly outnumbered BLACK STORM-PETRELS by a wide margin. Too bad that many LEAST STORM-PETRELS kept their distance, while the BLACK STORM-PETRELS came in somewhat closer to the boat. I think all still got satisfying looks, and I heard camera shutters clattering away. We estimated 3500 stormies total here, broken down to 2800 LEAST STORM-PETRELS, 700 BLACK STORM-PETRELS, and one ASHY STORM-PETREL. Nothing seen with any white on the rump anywhere.

Whew, relief! These rafts of stormies can be difficult to track down even when we know the general area to look. I’m not even sure these rafts form every day. Last trip we had several LEAST STORM-PETRELS scattered around the Nine Mile Bank and elsewhere. Today we saw NONE until we got to the raft. I’ve often been asked why storm-petrels form rafts. My thought is that it gives the protection of numbers, perhaps while conserving energy for the individual. That likely is an overly simplified answer. Why do they tend to form rafts in the same areas? Well they don’t always. Some years we’ve seen rafts on the Nine Mile Bank or San Diego Trough, or off La Jolla. This Thirty Mile Bank area is certainly popular, perhaps due to it’s being the most central area between the offshore islands and the mainland. Maybe it’s just close to a food source, away from possible predators, protected from weather or…who knows? Some up-and-coming young biologist might find a master’s or doctoral thesis in answering these questions, and others .

Needless to say these rafts, when found, are cause for amazement. I never tire of seeing them. I’ve described them as being “amoeba like”. Much like a single organism, the birds get up en masse and fly low over the water, change direction, break into multiple groups, and rejoin – all this as if a by a single mind. Great stuff. We departed the storm-petrel raft and retraced our track back to the southeast, then east back to San Diego. The trip back had more of a number of species already seen, with the addition of a close-in young PARASITIC JAEGER and a flight of shorebirds that included BLACK-BELLIED PLOVERS, a GEATER YELLOWLEGS, and some dowitchers. We also had another flyby passerine, perhaps a sparrow sp.

We were treated to a beautiful sunset as we approached San Diego’s harbor.
A very nice trip; calm seas, beautiful visibility, but maybe a little warmer than most of us wimpy Southern Californians would like. Certainly the highlight was the storm-petrel raft. Overall our species list was low, as were the total numbers of birds (except LEAST STORM-PETRELS). October pelagic trips usually produce much better numbers. Along with the hot air temperatures and calm conditions, the Sea Surface Temperatures (SSTs) were higher than we normally see. “Normal” for this time of year might be 67-71. Last year (considered a warm water year) we saw SSTs in late Sep. and early Oct. at 72-73. Today we recorded SSTs up to 77 F. These Sportfishing boats don’t carry scientific thermometers, but as small changes in water temps are important to finding fish, they are pretty accurate. I’ve also recorded 77 F on my last trip offshore in late September. That temperature is as high as any I’ve seen locally, and the water seems to me to be uniformly warm (hot) over a wide area. Scuba divers say that the warm water also extends down in the water column. These SSTs are clearly affecting bird distribution, e.g., BLACK-VENTED SHEARWATERS off Oregon, BROWN BOOBIES at the Farallons, a NAZCA BOOBY off Oregon, and on and on. What all of this means is, uncharted territory. Now “The Blob” is being doubled-downed on by a predicted mega “EL Nino” this winter. This could make a very interesting winter season, or a major disaster, or…? Time will tell.

Dave Povey
www.sandiegopelagics.com

Comments are closed.

Post navigation

  Next Post :
Previous Post :