Trip Report by Curtis Marantz

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1 May 2, :30 AM 7:22 AM Dana Point Harbor, Orange, CA, US Protocol: Traveling 2.0 kilometer(s) 23 species Comments: Jon Dunn, Brian Daniels, Tom Benson, Robert McNab, Thomas Ford-Hutchinson, and Curtis Marantz led the spring pelagic trip for the Sea and Sage Audubon Society aboard the Ocean Institute's R/V Sea Explorer with Peter Heistand as our captain. Most of us arrived at the dock around 6:30 am, after which we did a brief orientation before boarding the boat a little before 7:00 am, and then leaving at 7:02 am. We then spent some time cruising along the inside of the outer breakwater checking the gulls, pelicans, and cormorants before continuing offshore (see separate list). Upon our return, we cruised along essentially the same path but without stopping to check the breakwater, and with few people scanning the birds carefully (2:20-2:55 pm). Given that the birds seen represented mostly a subset of what we saw in the morning (with the only new species being a flock of four Great Egrets), the present list represents those birds encountered exclusively around the dock and during our morning departure. We encountered only a few land birds at the dock before we left port, and only a subset of these during the minutes that we spent around the parking lot on our return. Also on the boat were Steve Morris, Irene Horiuchi, Vic Leipzig, Bruce Aird, Jeff Bray, Jim Lomax, Brittany O'Connor, Monte Taylor, Steve Sosensky, David Evans, Amin Khalifa, Sherry Meddick, Pat Vranicar, Trish Gussler, Rick Shearer, Mike Huang, Don Hoechlin, Charles Baker, and many others who were familiar from previous trips. It was clear but a little hazy all day, calm or with a trace breeze from the east on our departure, but a moderate (10-15 knot) breeze from the west or southwest on our return. Temperatures at Dana Point increased from the mid-50s to the low 60s for our morning departure (56-60º F at the city hall, based on the NOAA website) but it was in the middle to upper 60s (65-67º F) on our afternoon return. 6:30-7:22 am. California Sea Lion - 15 (we saw only a few sea lions out near the end of the jetty, but with these including several rather small pups). The photo below was taken by Thomas Ford-Hutchinson Surf Scoter - 3 (a flock of three scoters was seen in the harbor in the morning, and on the return trip, an adult male was feeding along the breakwater) Brandt's Cormorant (CAM counted as carefully as possible the cormorants that were loafing near the tip of the breakwater) The photographs below by Curtis Marantz and Thomas Ford- Hutchinson show a bird in high, breeding colors \ Double-crested Cormorant - 3 (only a few Double-crested Cormorants were found on the breakwater today) Brown Pelican (CAM estimated at about 300 the number of pelicans on the breakwater as we left the harbor) Great Blue Heron - 1 (a Great Blue Heron was seen by some along the channel) Snowy Egret - 3 Black-crowned Night-Heron - 1 (an adult was seen by some on the trip) Osprey - 1 (seen by some as it flew over the channel) Black Oystercatcher - 4 (calling) 1

2 Three of these birds are shown in photos taken by Curtis Marantz and Jeff Bray Spotted Sandpiper - 2 (calling; at least one bird seen on the breakwater was in alternate plumage) Dunlin - 1 (a few saw a Dunlin fly over the breakwater as we exited the harbor) Heermann's Gull - 15 Western Gull (CAM counted as carefully as possible the gulls that were loafing on the breakwater and then dropping into our wake as we cruised down the channel) Caspian Tern - 1 (calling; we saw one or possibly two birds flying around the harbor) Royal Tern - 1 (a Royal Tern was seen by some as we cruised through the channel) Elegant Tern - 15 (calling; seen flying over the bay just beyond the jetty) Rock Pigeon (Feral Pigeon) - 6 Black Phoebe - 1 (calling; one seen around the dock was said to have been nesting here) Cassin's Kingbird - 1 (an unseen bird that was heard by others around the dock before we left port) American Crow - 4 (calling) Barn Swallow - 3 (several swallows were seen at the dock and along the channel) California Towhee - 1 (singing; an unseen bird heard from the parking lot) House Finch - 1 (singing; an unseen bird heard from the dock) May 2, :22 AM 2:22 PM Offshore waters between Dana Point and Lausen Sea Mount, Orange, CA, US Protocol: Traveling kilometer(s) 32 species (+2 other taxa) Comments: Jon Dunn, Brian Daniels, Tom Benson, Robert McNab, Thomas Ford-Hutchinson, and Curtis Marantz led the spring pelagic trip for the Sea and Sage Audubon Society aboard the Ocean Institute's R/V Sea Explorer with Peter Heistand as our captain. We headed southwest from port to the 150-fathom line, where we encountered a large flock of shearwaters, gulls, and terns, and subsequently laid out an oil slick to attract some storm-petrels. After checking these birds, we continued west to the Lausen Sea Mount, over which we spent some time with another large flock of foraging birds. We took a northwesterly course from the sea mount up the coast to the San Gabriel Marine Canyon, over which we checked the outer continental-shelf platform Eureka in search of the Brown Boobies that have been encountered here since January From the platform, we headed east toward the Newport Marine Canyon, from which we returned to Dana Point by cruising to the southeast along the coast of Corona del Mar and then Laguna Beach, generally remaining within five kilometers of shore. We found larger numbers of birds offshore than is typical for these waters, with numbers of Pink-footed Shearwaters, Black Storm-Petrels, and Sabine's Gulls being particularly noteworthy for a spring trip. Several Black Terns and the possibly now resident Brown Boobies were likely the most unexpected species, though even the latter species is likely to become an expected part of the local avifauna. Also on the boat were Steve Morris, Irene Horiuchi, Vic Leipzig, Bruce Aird, Jeff Bray, Jim Lomax, Brittany O'Connor, Monte Taylor, Steve Sosensky, David Evans, Amin Khalifa, Sherry Meddick, Pat Vranicar, Trish Gussler, Rick Shearer, Mike Huang, Don Hoechlin, Charles Baker, and many others who were familiar from previous trips. It was clear yet a little hazy overhead the entire day, but with an offshore fog bank that we never reached. Although essentially calm on our departure, a moderate (10-15 knot) breeze from the west or southwest came up over the course of the day. I suspect air temperatures were in the upper 50s to low 60s offshore. The dominant swell offshore seemed to be coming from the west at 3-4 feet, but the water was generally unsettled, and 2

3 with some wind chop after mid-day that made this one of the rougher trips that I have taken off Orange County. Conditions at the Dana Point waverider buoy, located 4.8 kilometers due west of Dana Point at 33 27' 31" N, ' 02" W, during the period that we were offshore represented a swell that dropped from 1.1 to 0.9 meters (= 3.6 ft and 3.0 ft, respectively), with a dominant period that ranged from the south to the west at seconds but an average period of seconds, and water temperatures that increased from 15.7º C to 16.9º C before dropping back to 16.4º C (= 60.3º F, 62.4º F, and 61.5º F, respectively; these values taken from the NOAA website). By contrast, conditions during this period at the San Pedro South buoy, located midchannel to the southwest of Huntington Beach at 33 34' 40" N, ' 04" W, were a wave height of meters [= feet], with a dominant period ranging from the south to the west (but at times from the north late in the day) at seconds, an average period of seconds, and water temperatures of º C [= º F]. 7:22 am - 2:22 pm (for the offshore waters beyond the breakwater). The track for this trip shown below was taken by Tom Benson. and the following by Curtis Marantz California Sea Lion - 25 (we saw a few sea lions offshore, but most were loafing on buoys); Common Dolphin (we saw many dolphins over the course of the day, yet none were in large groups). Surf Scoter - 2 (some aboard saw a distant a pair of scoters in flight) Pacific Loon - 50 (we encountered during our afternoon return along the coast off Laguna Beach a single flock of about 15 loons that were foraging on the water, but we saw singles and small flocks flying by at various times of the day; the vast majority of these birds were in alternate plumage) The photograph below was taken by Jeff Bray. Common Loon - 3 (I missed two adults in alternate plumage that others saw as they flew by, but I think we all saw a basic-plumaged individual on the water that was presumably a young bird) Eared Grebe - 1 (a single bird in alternate plumage was seen on the water off Laguna Beach) Pink-footed Shearwater (it was difficult to determine the total number of birds seen, yet CAM estimated 200 birds in one flock that we encountered just off Dana Point and we continued to see good numbers over the course of the trip; many of these birds were clearly in wing molt) The photos below were taken by various photographers. by Curtis Marantz by Curtis Marantz by Tom Ford-Hutchinson by Tom Ford-Hutchinson by Jeff Bray by Jeff Bray by Tom Ford- Hutchinson by Tom Ford- Hutchinson Sooty Shearwater (CAM estimated 1500 birds in the flock off Dana Point in the morning, but we encountered good numbers over the course of the trip) by Curtis Marantz by Curtis Marantz This photo of a leucistic individual was taken by Thomas Ford-Hutchinson Black-vented Shearwater - 20 (we saw in the large flock off Dana Point at least birds, yet we encountered only a few additional birds the rest of the day) 3

4 Black Storm-Petrel (we encountered today unusually large numbers of storm-petrels for a spring trip, including about 15 birds that visited a slick of oil that we put out in the shearwater flock just off Dana Point) The photos below were taken by Tom Benson and Jeff Bray. by Tom Benson by Tom Benson by Jeff Bray Brown Booby - 4 Upon reaching offshore oil platform OCS-P-030-Eureka, located about 14 kilometers southwest of Huntington Beach at N, W, we spotted one adult and three subadults perched on a structure on the north side of the platform. We then spent a short time studying and photographing these birds before continuing on our way shortly after one of the subadults made a brief, looping flight that ended with it returning to the same place where it began. These birds were comparable in size to the Western Gulls that were standing nearby, yet they were somewhat different in shape. All four birds had plump bodies with a full-chested appearance and a roughly diagonal posture when perched on the rail. I also thought these birds each had a moderately long tail and relatively long wings. The subadults each had a smoothly rounded head and a stout neck that was shorter than that of a cormorant, and on at least two of the young birds I noted the conical bill that tapered from a heavy base to a pointed tip along a relatively straight culmen. I never did see the head or really even the neck of the adult, which was sleeping. The bird that we saw in flight had long wings that were slim throughout and tapering to pointed tips. This bird s neck was longer than that of a gull, but both shorter and stouter than that of a cormorant, the head was large and more bulbous than that of a cormorant, and the large bill was again evident. Also visible on the flying bird was a relatively long, tapered tail. The three subadults appeared similar in their plumage patterns, with each having the head, neck, upperparts, and wings uniformly dark brown and seemingly a duller shade of brown than the adult. Each of these birds also had the belly and flanks a dingy, grayish-white color with speckling or mottling of dark brown to grayish throughout, yet the demarcation between the brown breast and the dingy belly was a sharp one that extended straight across the lower breast. I further noted on two birds what appeared to be a whitish stripe that extended from the shoulder back across the upper part of the closed wing. I am not sure if this represented paler feathers, or instead, a parting of the feathers revealing either bare skin or the bases of feathers that are normally hidden. I further noted that the adult was a more purely chocolate-brown color on the upperparts, wings, breast, and whatever I could see of the neck and tail, but even more conspicuous was that the belly and flanks of this bird were uniformly snow-white without any of the darker markings that were evident on the younger birds. Given that I never clearly saw this bird s head, I could not be sure about its sex, but others suggested that it was a female. I further noted on the subadults a medium-gray bill, and what appeared to be dark gray legs, but I had a hard time seeing the eyes or the facial skin. I was unable to see the bill, eyes, or facial skin on the adult, but I did think its legs were paler and more yellowish than those of the younger birds. The photo below was taken by Jeff Bray by Jeff Bray Brandt's Cormorant - 10 (we saw only a few cormorants offshore) Double-crested Cormorant - 1 (the only Double-crested Cormorant seen offshore was an adult in alternate plumage) Pelagic Cormorant - 1 (a single bird perched on outer continental-shelf platform Eureka) Brown Pelican - 35 (we saw many fewer pelicans offshore than we saw at the harbor, and most that we did see were quite close to shore) 4

5 Western Sandpiper - 2 (these sandpipers were seen by only a few) Red-necked Phalarope (the vast majority of phalaropes seen well enough to identify were Red-necked, but many of these birds were seen at distances too great to identify with confidence) The photographs below were taken by Thomas Ford-Hutchinson and Jeff Bray Red Phalarope - 50 (Red Phalaropes represented maybe 10% of the overall phalarope count, but these did include both birds in basic plumage and a few females in fine, alternate plumage) The photograph below was taken by Thomas Ford-Hutchinson Red-necked/Red Phalarope (I would have considered about 20% of the more distant phalaropes to have been best left unidentified, though the vast majority of these were presumably Red-necked) Pomarine Jaeger 10 (most of the jaegers were seen on our return trip in the afternoon, on which CAM noted five light-morph adults, one dark-morph adult, and a subadult bird, but we saw two or three others between the sea mount and the oil rigs). by Tom Benson Scripps's Murrelet - 8 (despite challenging sea conditions for detecting small alcids, three pairs of murrelets were located on the way out to the sea mount by TFH and an additional pair was spotted on the way to the oil rigs by TAB) Cassin's Auklet - 12 (we saw some of these birds on the water off Huntington Beach, but others only in flight; in general, the choppy seas made it difficult to spot small alcids on the water) The photos below were taken by Thomas Ford-Hutchinson and Jeff Bray Rhinoceros Auklet - 4 (one pair was seen and photographed on the way to the sea mount and another pair was flushed on the way to the oil rigs) by Tom Ford-Hutchinson Sabine's Gull - 50 (the 50 Sabine's Gulls encountered on this trip was quite a high count for inside the channel) The photos below taken by Thomas Ford-Hutchinson and Tom Benson include a bird that appears to represent a subadult by Tom Benson by Tom Ford-Hutchinson Bonaparte's Gull - 10 (two young birds were well seen on the water, but most of the others were distant) The photographs below by Curtis Marantz shows one of the young birds Heermann's Gull - 25 (we saw relatively few Heermann's Gulls offshore, but some of these were adults in fine, alternate plumage) 5

6 Western Gull (estimates by some were of 100 Western Gulls and 250 California Gulls, but numbers may have been even higher) California Gull (California Gulls represented the bulk of gulls that we saw offshore) Herring Gull - 1 (an adult that was spotted by Jon as we neared outer continental-shelf platform Eureka) Glaucous-winged Gull - 2 (both were first-spring birds) Least Tern - 3 (a few saw three, distant Least Terns among tern flocks over the sea mount) Black Tern - 12 Two birds were spotted by Brittany O Connor and seen by a few en route to the oil rigs, but two additional flocks of four and six birds, respectively, were noted by TFH and others off Newport Beach. I saw only these latter two flocks, and even these at moderate distance as they flew by to the north. I was able to see that these were small terns that flew with rapid wing-beats on tapered wings and short tails. They flew in direct lines to the north and well above the water, which easily distinguished them from the storm-petrels that we had been seeing. Even at a distance, I was able to see that these birds had generally dark bodies, medium to dark gray uppersides to the wings, and what appeared to be uniformly pale underwings, but given the distance at which I made my observations (and less than ideal light), I had a hard time seeing much more detail on the six or eight birds that I managed to see, though all appeared to be in alternate plumage. Common Tern - 12 (several birds, at least some of which were adults in alternate plumage, were seen over the sea mount) Forster's Tern - 15 (calling; I saw maybe half of the 15 Forster's Terns that we encountered) Elegant Tern (calling; we saw large numbers of Elegant Terns throughout the day, and if anything, this number may represent an underestimate) by Tom Benson warbler sp. - 5 (a single unidentified warbler crossed the bow on the way to the sea mount and a flock of four additional warblers was later seen by TFH flying back in the direction of the shore as we cruised out to the oil rigs) 6