WESTERN BIRDS

Volume 7, Number 4, 1976

PELAGIC BIRDS OF MONTEREY BAY, CALIFORNIA

RICHARD W. STALLCUP, 4409 44th Avenue, Sacramento, California 95824

Monterey Bay is one of the best and most accessiblelocalities in the world to observea large variety of seabirds.At any time of year many speciesof pelagicbirds and mammalsmay be seen. The annualpassing of migrants,the inclusiveperiods of residencyof winteringanimals and their favored haunts on the bay have now been studied adequately enoughthat we may generalizethem in print. In caseswhere descriptionsin popular field guidesare incomplete or inaccurate,a pieceon identificationat seais includedin the follow- ing annotatedlist of selectedbird species.

THE BAY Monterey Bay is ideal for pelagicbird trips for severaloutstanding reasons: 1) The edge of the continentalshelf is very closeto shoreat this point, bringingdeep-water species in and cuttingdown boat com- muting time to truly oceanicwaters. 2) The Monterey SubmarineCanyon, the main underwatergeograph- ical feature, is very deep and upwellingscaused by strongnorth- west winds at both rims are attractive to seabirds,particularly storm-petrels. , 3) The bay itself is half-moonshaped and relativelysheltered. 4) The bay is situated far enoughsouth to appeal to warm water speciesand far enoughnorth to appealto cold water species. 5) The weather is stable enoughto allow year-roundtrips. Though the water may be quite rough at times, we have never witnessed a trip on a largerboat canceledfor that reason. ACCESS There are many boatsfor charterfrom Fisherman'sWharf in Monter- ey and a few at Santa Cruz and Moss Landing. All are relativelysmall (fewer than 50 passengers)and none have galleys. WesternField Orni- thologists,many local Audubon chapters and other nature oriented WesternBirds 7:113-136, 1976 113 MONTEREY PELAGICS groupsschedule regular trips which are advertisedin their newsletters and journals. The averagecost is between 12 and 15 dollarsand, at that, still a bargain. Becausethe trips are very popularthey are filled on a first come,first servedbasis and mostalso have waiting lists. Often duringthe tourist seasonand on weekendsshort, inexpensive ($3-5) sight-seeingor whale-watchingtours are run from Fisherman's Wharf, Monterey. Checkthe charteroffices near the end of the pier for schedules. No reservationsare necessary. These trips can be very productivefor birders. Bring food, drinks and warm and waterproof clothes. Afternoons may be warm, so be adaptable.

SEASONS Autumn (early Augustto mid-November)is by far the best for num- bers and variety of seabirds. During this time, at least in the last five years, there have been five or more birdingboat trips per year, vastly more than at any other season.Consequently most of our information refers to fall. Winter is very good for seeinglarge numbersof alcids, Black-legged Kittiwakes and Northern Fulmars and is perhapsthe best seasonfor Fork-tailed Storm-Petrel and Short-tailed Shearwater. Springis good for variety (though alwaysless than fall) and for see- ing the birdsin high plumage. Summer is poorly known but is the best seasonto seelarge numbers of Black-footed Albatrosses.

AUTUMN TRIPS

The best way to proceed (and we have tried many) is to leaveMon- terey harbor as early as the boat operatorswill go (0800 or 0900) and parallelthe PacificGrove shore (checking for Thick-billedMurres among the Commonsand looking at terns, grebes,scoters, Sea Otters and sea lions) until reachingPoint Pinos. Often by this time the skipper will have heard from fishing boats that "the birds" are slightly south and you may wishto detourbriefly toward Carmel Bay. If not, go straight out 5-15 km or more, then cut north toward Santa Cruz to the Monter- ey SubmarineCanyon. Turn east (toward the large concrete smoke stacksat Moss Landing) alongthe canyon'ssouth or north rim, looking for raftingstorm-petrels. Then, as time permits,meander back south in the bay to the harbor. By goingthis way the boat will neverbe heading directlyinto the suln,you are in the heaviestbird concentrationsearly and later the storm-petrelstend to raft in largernumbers. Always devi- ate from courseto head for feedingflocks and do not be too anxious to get far offshoreas birding is often very bleak there. When approach- ing birds on the water, get the skipperto maneuverthe boat so that it 114 MONTEREY PELAGICS is between the sun and the bird for good lightingand so that the boat is broadsideto the bird to allow everyonea goodview. The tendencyis to headstraight for the animaland then only those on the bowcan see it.

SPECIES ACCOUNTS

PROCE LLA RI FORMES

LAYSAN ALBATROSS, Diomedea immutabilis. There are at least five records for the Monterey Bay area, all between 29 November and 27 May. All are recent. Field identification: The bird is mostly white below, has entirely dark gray- brown upper surface of wings and back and has a yellowish-pink bill and pink legs and feet. The white rump is set off by dark rectrices. Laysan is the same bulk as Black-footed Albatross and averagesslightly larger in wingspread. BLACK-FOOTED ALBATROSS, D. nigripes. Numbers vary year to year de- pending upon water temperature and thus, food availability. Chances of seeing one or more near the continental shelf or above the Monterey SubmarineCanyon are very good from May to mid-September and marginal at other times. Large numbershave been found consistentlyin June and July and over 100 individuals have been found together on more than one occasion, usually at active fishing trawlers. Field identification: Mostly uniform dark brown with some white in primary shafts, on the feathers at the base of the bill, and on under and sometimesupper tail coverts. Very old birds may become extremely pale on the belly and under- wings. Bill, legs and feet are always black. Immature Short-tailed Albatrosshas a pale bill, legsand feet and is more uniform brown.

Black-footedAlbatross (Diomedea nigripes). Off Eureka, California, 6 May 1973. Photo by John Luther. 115 MONTEREY PELAGICS

SHORT-TAILED ALBATROSS, D. albatrus. Formerly very common near shore in central California. Now nearly extinct due to destruction of breeding coloniesin the Bonin Islands,600 km southof Japan. It waslast seenin California waters in February 1946. Becausethe speciesis now a Japanesenational monu- ment, is rigidly protected and slowly increasingand becauseMonterey Bay is well within the species'traditional range, it seemslikely that somedayit will be seen here again. Field identification: Adults are similar to the LaysanAlbatross but have white backs and may be washedwith buff. Immaturesare all uniform dark chocolate brown, but have pink bills, legsand feet. Short-tailedsare distinctly larger than our other two albatrossspecies.

KEY TO THE REGULAR SHEARWATERS I. If belly white seeA II. If belly dark see B A. 1. Large, slow wing beat, uniform gray-brownabove, light pink basebill and pink feet, mottled gray-whiteunderwings...... Pink-looted Shearwater 2. Medium size, black cap, gray back, sharplycontrasting black and gray wings,underwings bright white narrowlybordered with black, bill dark...... Buller's Shearwater 3. Small, uniform dark aboveand light below (exceptbroad trailingedge of underwingsand vent dark), fast wingbeats,bill dark...... Manx Shearwater B. 1. Large size, slow wingbeats,all dark aboveand below except light based bill and pink feet...... Flesh-looted Shearwater 2. Medium size,all dark blackish-brownabove and belowincluding bill and feet exceptingsilvery white lining on the dark underwing,usually ig- nores boats...... Sooty Shearwater 3. Medium size, generallyshort bill, uniform dark sooty-graybrown all over except for evenly smoke coloredor brownishunderwings, usually attracted by boats...... Short-tailed Shearwater

Exception: Northern Fulmar--amedium sized procellariform of variableplum- age (dark, light, intermediateand mottled) that can be told from all othersby its thick neck and roundedhead, yellow bill (quite dark in darkestphased birds), roundedwing tips and, in all but the darkestplumages, light patchesin the outer wing. NORTHERN FULMAR; Fulmarusglacialis. First appearsoffshore in late Sep- tember and quickly increasesin numbersto a peak in mid-November.There are one 10 June and one oversummerrecords. The summeringbird wasnot healthy. A few alwaysoverwint•'• but someyears they are abundantand can be seeneat- ing scrapsof fishwith gullsat harborsand flyingnearshore from coastalpoints. Field identification:Highly variablein plumage(light, dark, intermediateand mottled). Seekey to the shearwaters.White shafted primaries in all but the dark- est phaseappear as a white flashon the uppersurface of the wing. Dark birdsare usuallymore common by 8 or 9 to 1 but in winterof 1973-74dark and light were equallycommon and in 1974-75light birds were more common than dark. 116 MONTEREY PELAGICS

Pink-footedShearwater (Puffinus creatopus). MontereyBay, fall 1976. Photo by Bruce Sortie

Northern Fulmar (Fulman•sglacialis). Monterey Bay, November1973. Photo by Bruce Elliott 117 MONTEREY PELAGICS

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Buller'sShearwaters (Puffinus bulleri). Monterey Bay, October 1974. Photos by Bruce Elliott

118 MONTEREY PELAGICS

PINK-FOOTED SHEARWATER,Puffinus creatopus. Fall-Guaranteed. Usually the second commonest shearwater after Sooty. Numbersdrop abruptlyin late Octoberand early November. Winter-Irregular; probablynot presentevery year and when present,numbers are small. Spring--Beginsto reappearnear the end of Marchand is then presentin small numbersuntil late July when the fall influx begins. Field identification: Large, relatively slow flying, uniformly gray aboveand white below. Underwinglinings imperfectly white, flight feathersdark. Feet pink, bill pink basedand black tipped. Solitary or gregariousbut seldomin homogeneousflocks with its own kind. On the water seewhite throat and chest, pink basedbill and uniform gray upperparts.

BULLER'S SHEARWATER, P. bulleri (also New Zealand, Gray-backedShear- water). Fall-Normally only occurs in California waters in the fall from late June through November with a probable peak during the first week of October, but there are two recent winter records. On some trips seen in hundredsbut most often from 10 to 70 individuals.Seems to be increasingin numbers. Field identification: A really striking bird to which no field guide has done justice. Immaculatelywhite below narrowly marginedon undersideof wingsby black. Above, distinctly black capped,gray backedand with an obviousdark on gray extended "W" pattern on upper wing surfaces. On the water seeblack cap distinct from very white throat and chest (as in Manx), evenlygray back. While flying at ease,Buller's tend to arc more frequently than do Pink-footedsand they do not beat the wingsnearly as quickly or asoften asManx. Homogeneousflocks are sometimesencountered and their synchronizedflight is beautifully graceful.

MANX SHEARWATER,P. puffinus(including Black-vented Shearwater). Fall-Irregularly reported in August and September;most recordsare from mid-October to late November. Winter-There are a very few winter records,indicating the speciesis irregular then in tiny numbers. Spring-The three records for early May suggesta possiblesmall but regular passagethen. Field identification: Uniform dark blackish-brownabove and entirely white below except for flight feathers and wing leading-edgemargin and in this, the "Black-vented"race, a dark crissum. Very small, fast flying. Manx Shearwaters favor shallow water and are probably as often seen from shore as from ocean goingvessels.

SOOTY SHEARWATER, P. griseus. Fall-Flocks of literally millionspass near-shore from mid-Julythrough August and the speciesmay still be consideredabundant here throughmid-November. Other seasons-Sooty Shearwatersare always present in varying numbersin California watersand it would be a uniqueexperience to bird a day on Monterey Bay without seeingany. Mid-winter is the lowest ebb. Field identification: Medium size, uniform gray-brownwith silveryunderwing linings and blackish flight feathers(see Short-tailedShearwater). Birds molting flight feathersoften appear to have white wing patchesand we have seensym- metrically partial-albinoindividuals on more than one occasion. See Cape Petrel. 119 MONTEREY PELAGICS

SHORT-TAILEDSHEARWATER, P. tenuirostris(formerly Slender-billed Shearwater).The statusof thisspecies has changed in thelast century in Cali- forniawaters. Formerly considered common near shore, our recent records indi- cate that it is at best uncommon. It is most often seen in mid-winter. Very difficult to identify. Fall--Rarelyreported before mid-November. Otherseasons-Occasionally seen from November through February; records fromspring, summer and early fall arequestionable. Fieldidentification: Slightly smaller than the very similar Sooty Shearwater but underwingsuniform smoke or brownish-gray(not merely lined with silver- whiteas in Sooty)but notblack as in somedescriptions. Body color is subtly lessdark (blackish-brown) than in Sootyand is more gray-brown. At closerange thebill averagessmaller than the Sooty Shearwater's in length and less so in bulk. Seenin flightthe tail is noticeably shorter. Short-taileds often show interest in boats, whereasSooties seldom do.

FLESH-FOOTED SHEARWATER, P. carneipes(formerly Pale-footedShear- water). Fall--Earliestrecord 8 Augustand latest 1 December. Rarebut regularon MontereyBay and never more than one or two per trip, if any. Other seasons--Tworecords for May indicateirregular spring passage in tiny numbers. One 21 Februaryand one 13 Marchrecords suggest rare wintering. There are no recordsbetween 28 May and 8 August. Field identification:Large with proportions,behavior and style of flightvery similar to that of the Pink-footed Shearwater (some authorities believe that the two are conspecific).Mostly very dark throughoutbut with pale (whitishor pinkish)based, black tipped bill andlight colored legs and feet which can best be seenas the bird is water-runningto gainflight. On the waternote slightly larger sizethan SootyShearwater and obvious light based bill. Firstyear Heermann's Gullsare similarly dark blackish-brown throughout, have pink based, black tipped bills but are smaller,have black legsand feet, fly bouyantlyand are obviously gulls, not shearwaters.

Flesh-footedShearwater (Puffinus carneipes). Monterey Bay, 5 October1973. Photo by John Luther

120 MONTEREY PELAGICS

STREAKED SHEARWATER, Calonectrisleucomelas (formerly White-faced Shearwater). A singleindividual was collected from a mixed flock of shearwaters on 3 October 1975 on Monterey Bay. It is the only record for the northeast Pacific. Field identification: Nearly as large as a Pink-footed Shearwater. Face, neck and dosed wings with distinct black streaks. Mostly brown aboveincluding tail. Bill yellowish,legs and feet pinkish. Range--Breedsand winters strictly in the western Pacific but is highly migra- tory there. This bird was truly out of rangebut the speciesmay well occuragain in California waters. CAPEPETREL, Daption capcrisis. Exceedingly rare. One shot "off Monterey" before 1853 is questionable. Two recent sightrecords are for 9 September1962 and 13 March 1974. Field identification: The striking black, white and checkeredpattern of this bird make it seeminglyunmistakable; however, it is not dissimilarto somemottled Northern Fulmarsand we haveseen symmetrically partial albinisticSooty Shear- waterswhich looked surprisinglylike this species. FORK-TAILED STORM-PETREL, Oceanodrornafurcata. Another species which seemsto fluctuate in numbersaccording to water temperaturepatterns, preferringcold conditions. Someyears almost common. Fall--Recently but one or two have occasionallybeen seen in the greatflocks of Black and Ashy storm-petrelsabove the Monterey SubmarineCanyon or near Point Pinos. Other seasons-In optimum years (none in the last ten), Fork-tailedsmay be seennear shore during any seasonexcept summer. Recently however,the few recordsaway from fall have been for mid-winter and most of these, blown near- shoreby northwestgales. Field identification: This is the only uniform light gray North Pacificstorm- petrel but phalaropes(especially Red) and other shorebirdsat seamay be prob- lematical. Storm-petrelshave bouyant, pumpingflight (not labored and hurried asdo shorebirds)and appearblunt headedand longtailed.

LEACH'S STORM-PETREL, O. leucorboa. Very rarely encounterednear Monterey;the few recentrecords are near the edgeand beyondthe continental shelf, except for individualsblown to shoreby northwestgales. A preferencefor more offshore,deeper water is indicated. Seasons-All of the recordsfor Monterey Bay are for Octoberand November. A rather common breeder on the Farallon Islands. Field identification: Only white-rumpedindividuals have thus far been detect- ed off northernCalifornia (a dark rumpedform occursoff southernCalifornia). The white rump patch is actually partially dividedby a dark bar and appears smudgy,not brightwhite. The smudgywhite rump,dark brown plumage, notched tail (hard to see),dark underwingsand rathererratic, nighthawk-like flight aswell asthe largesize (only slightlysmaller than a Black)and relativelylong wings,bent or bowedwill identify this species.

GALAPAGOS STORM-PETREL, O. tetbys kelsalli. An individual of this, the southern,Peruvian race was taken alive at Carmel on 21 January1969, after five days of southerlygales. It was the first North Americanrecord for this raceand the first U.S. recordfor the species.It is unlikely that this bird will everbe en- counteredon a Montereypelagic trip. Field identification:Small and quite black with a squareor very slightly notchedtail and long, triangularwhite rump patch. From Leach's:it is much 121 MONTEREY PELAGICS

122 MONTEREY PELAGICS smaller and darker with relatively much shorter wings and a triangularbright white rump patch. FromWilson's: somewhat smaller with blackfeet, a triangular white rump patch and deliberateflight. WILSON'S STORM-PETREL, Oceanitesoceanicus. One to three individuals havebeen found by fortunate birderson trips from Septemberto Novemberfor the last six yearsassociated with the greatstorm-petrel flocks over the submarine canyon. There are probablymore recordsfor MontereyBay than for the entire rest of the North Pacific. Field identification: Medium sized and quite black with a bright white rump patch, roundedtail, yellow foot webbing(hard to see)and fluttery, danglyflight and behavioridentify this bird. It is very long-leggedand when flying directly the feet usuallyextend slightly beyond the tail tips but rarely are carriedreflexed forward (Will Russellpers. comm.). Thoughvery rare, it is the most likely white- rumpedstorm-petrel to be seeninside Monterey Bay during periodsof calm wind. LEAST STORM-PETREL,Halocyptena microsoma. Very rare andonly pres- ent in yearsof warm water. Hasonly beenfound in 1969, 1972, 1974 and 1976 and only from Septemberto late October. Most timesthat this speciesis correct- ly identifiedextralimitally (as in MontereyBay) i• hasbeen by observerswho have become familiar with the bird where it is more common. Field identification: The smalleststorm-petrel, all dark with a wedge-shaped tail. Contrary to what other authorshave suggested, the tail appearsrelatively short; not long. Flightis fairly direct with rather deepwingheats, similar to those of the BlackStorm-Petrel, but more rapid. ASHY STORM-PETREL, Oceanodroma bomocbroa. Abundant at diurnal roosts3-10 km off MossLanding above the rimsof the Monterey SubmarineCan- yon from August through November. In the fall, individuals are occasionally seenduring morning hours flying toward the roost from other sectorsof the bay. Other seasons-Occasionallyseen winter and spring especiallyin-bay during northwestgales. A commonbreeder on the Farallon Islands. Field identification: All dark with lighter wing linings and a notched tall. Medium size with wingheatrhythm between that of Black and Least storm-petrels but more shallow. The wings are raised only to and not above horizontal before the down-stroke. Familiarity with thesethree is the best way to tell them apart. It is often more of impressionthan detail. BLACK STORM-PETREL, O. melania. Common in autumns of warm water and uncommon in others. The earliestdate is 8 August 1974. Sometimesnearly as numerousas the Ashy Storm-Petrelwith whichit sharesthe samehabits and distribution on Monterey Bay. Other seasons--Doesnot occur in winter, springor early summer. Fieldidentification: Large and dark with dark underwingsand a slightlynotched tall. Flight is deliberateand wingbeatsare fairly deepand spaced reminiscent of the flight of a Black Tern. Unlike the Ashy Storm-Petrel,the wingsare raised definitelyabove the horizontalbefore each down-stroke.

PELICANIFORMES RED-BILLED TROPICBIRD, Pbaetbon aetbereus. There are two records, 29 June 1973 and 14 July 1970, both of adult birds. Field identification: Flight rapid like an acceleratingRock Dove. From below see dark inner secondaries.From above seeblack speckledback and inner wings. White-tailedTropicbird, which hasdefinitely occurredonce in southernCalifornia, has white inner secondariesfrom below and solid black bars on the wings from above.

123 MONTEREY PELAGICS

MAGNIFICENT FRIGATEBIRD, Fregatamagnificens. There are severalrec- ordsfor the fall between15 Julyand 20 October.It is at besta rareand irregular speciesand mostobservations are from shore. Field identification:See any goodfield guidebut do not assumethat any frigatebirdis a Magnificent.Check them carefully. The rustycoloration on the breastand headof the immatureGreat Frigatebird(F. minor) may be conspicu- ousor it maybe restrictedto just a few feathersand hence visible only at close range(Alan Craigpers. comm.). DOUBLE-CRESTED CORMORANT, Pbalacrocoraxauritus. Very rarely seen alongthe PacificGrove shore or on boattrips in the southernpart of the bay. Occasionallyseen nearshore from Santa Cruz to MossLanding. Most often found in fall and winter. Field identification:A largecormorant with a distinctorange or yellowgular pouchand in the immatureoften with a mostlyyellow-orange bill. Immatures arelight brown above and often very whitish below. In flight,the head is clearly distinct from the neck and the neck itself is carried crooked at all times (Figure 1).

BRANDT'SCORMORANT, P. penicillatus.Common on rocksalong the Pacif- ic Grove shoreand very commonon MontereyBay feedingin mixed flockson surfacefish or flying in smallto largeflocks very closeto the water. A common breeder at Point Lobos and abundant in winter probably due to influx from FarallonIsland populations. Present throughout the year. Field identification:A large cormorant. Breedingadults with an incredible sky-blueand pale yellow gular pouch. In other plumagesand at somedistance the gularpouch appears tan (sometimesyellow but neveras bright as that of the Double-crestedin any condition). Immaturesare dark brown to blackishabove and slightlypaler below, lightest on the chest. In flight the headis distinctfrom the neck. The neck is carriedstraight during normal commutingflight (Figure 1), but is sometimes crooked when individuals look at some attraction like a boat or a feeding bird flock. PELAGIC CORMORANT, P. pelagicus.Always present but neveras common as Brandt'salong the PacificGrove shore and in MontereyBay. Breedsin small numbersat Point Loboson cliff facesaway from the largeBrandt's colonies. Field identification:A relativelysmall cormorant. The red gular pouchof springbirds is difficult to see but adultsin vernalplumage have obvious white oval flank patcheson eachside of the rump. Immaturesare nearlyuniform dark brown unlikethe two largerspecies which show pale areas on the underparts.The iridescenceof adultsis consistentlyand beautifullygreen. In flight the headand neck are alwaysstraight and seemvirtually to taper to a point. There is little apparent head (Figure 1).

BLUE-FOOTED BOOBY, Sula nebouxii. One adult and three immatures were seen from Lover's Point on 16 October 1971 and two immatures were there the next day. Blue-footedBoobies staged a major invasioninto southernCalifornia that year. Seethe list of reasonablypossible species below.

CHARADRIIFORMES RED PHALAROPE,Pbalaropus fulicarius. The seasonalstatus of thisinvasion- ary bird is quite variable.There are alwaysa few presenton the bay from late Sep- tember to late November,and from late April throughMay. Someautumns, how- ever, (about four in ten) many thousandsappear and duringthese invasions the speciesmay be presentfrom as early as mid-Augustwith individualslingering throughout the winter. 124 MONTEREY PELAGICS

Figure1. The ident,•fyingcharacters of cormorantsin flight. Above,the Double- crested,demonstrating its largebill and headand crookedneck. Middle,the Brandt's,with its largebill and headand straightneck (see text). Below,the Pelagic,a smaller bird with a slimneck and bill, and very little apparenthead. 125 MONTEREY PELAGICS

Field identification: Generally chunkier than the Northern Phalarope with a distinctly biggerhead, shorter, thicker neck and shorter,stouter bill. The body is more robust and circular. In fall the back is uniform pale gray, darkeston the hindneck, and the dark eyestripemay be very nearly lacking. With its bold white wingstripe,the flying fall Red Phalaropestrongly suggests a Sanderling.Contrary to popular opinion the bill color of most individualsin the fall is black, not yellow. The basic call note is a "pik" similar to but louder than that of the Northern Phalarope;however, a short,high trill is sometimesgiven, particularly in the spring. Breedingplumaged birds canhardly be mistaken. NORTHERN PHALAROPE, Lobipes lobatus. Generallyearlier and more reg- ular than the Red Phalarope. The speciesis present from late July through Sep- tember and from early April to early May, sometimesin largenumbers. There are only three winter records,all onshore. Field identification:Thinner in all respectsthan Red Phalarope. The headis smaller, the neck longer and more slim and the bill narrower and more sharply pointed. The back is generallydarker gray to black and mostoften containslight stripes, but winter plumagedadults can be surprisinglylight gray with indistinct stripes. The blackish crown, hindneck and eyestripeare much more evident in this than in the Red. The basic calls are a detachedseries of"pik" notes,similar to but flatter than those of the Red. JAEGERS. To identify immaturejaegers, some comparative experience is man- datory. LONG-TAILED JAEGER, StercorariusIongicaudus. Records extend from 30 August into late October but the speciesis very rare here and is not identified each year. They may be more common farther seaward with flocks of Arctic Terns. Field identification: Adults with their extremely long, flexible pointed tail feathers, clearly isolated black cap and immaculate white chestsare easy. Im- maturesare usuallynot safelyidentifiable from Parasiticsor evenfrom Pomafines but they do fly more gracefully, even ternlike, are more uniform gray and have three or lesswhite shaftedprimaries. The undersurfaceof the wingsare beautiful- ly and evenly marbled and the flanks are often barred vertically with wide, dark stripes. The bill is quite smallbut so are thoseof someParasitics.

PARASITIC JAEGER, S. parasiticus.Occurs regularly from late July through mid-Novemberwith a probable peak in mid-September. A few are usually seen on pelagic trips during this time generally within a kilometer or two of shore. Often seenfrom shorebetween Pt. Pinosand MontereyHarbor. Other seasons-Thereare a few scattered recordsfrom Decemberinto April and only two betweenearly May and early July. Field identification: No obvioussexual dimorphism but many phases.May be confusedwith Pomarine(see below) or Long-tailed(see above) jaegers. Adults with elongatedcentral tail feathersare easybut be awarethat Long-tailedJaegers can haveshort (broken or growing)tail feathers.Parasitics have generally smaller headsand bills than Pomarinesand only 3 to 5 white shaftedprimaries. At ease flight is like a mediumsized gull. POMARINE JAEGER, S. pomarinus. More common than ParasiticJaeger except perhapsvery near the Pacific Grove shoreline. As many as 40 have been seenon tripsduring late Septemberand early October. Other seasons--Afew linger throughthe winter and there is some passagefrom early April into the first weekof May. From mid-Mayto mid-July(when the first fall returneesarrive) there arevery few acceptablerecords. 126 MONTEREY PELAGICS

PomarineJaeger (Stercorarius pomarinus). Monterey Bay, fall 1976. Photo by Bruce Sortie

ParasiticJaeger (Stercorarius parasiticus). Monterey Bay, fall 1976. Photo by Bruce Sortie

127 MONTEREY PELAGICS

Field identification: Adults with full tails are easy and obvious. Immatures may be mistaken for Skuas or ParasiticJaegers. After seeingmany of both, one can sometimestell Pomarinesfrom Parasiticsby the "pom's" larger proportions (frame, bill, head, neck) more primarieswith white shafts (5 to 8 versus3 to 5) and their rhythmand "weight"of flight (normal,at easeflight only) resembling a Herring Gull for Pomarine and a Heermann's Gull for Parasitic. See Skua. SKUA, Catbaractaskua. Skuashave been seenon Monterey Bay every fall since 1962 and as many as 10 have been reportedby somefortunate observers there. The speciesis missed,however, more times than it is seenand can never be guaranteed. Fall recordsrun from late July throughOctober. Other seasons-Thereis one record eachfor March, April, May and June. Note: Some authoritiesrecognize five speciesof Skua and most (outsidethe United States) recognizeat least three. All of the live birds we have been able to specifically identify have definitely been the South Polar $kua, C. rnaccorrnicki, and there is no publishedacceptable record of any other form from the northeast Pacific. The bird is similar to the Great Skua and similarly, immaturesare chocolate brown.Adults, however, are brown with gold and yellow hackles not gray-brown uniformly like adult Great Skua. Of the other three Skuasthere is a really big blackishone, a dull brown one and a ferruginouscolored one. Maccormickihas the shortest,stubbiest bill of all. If possiblephotographs should be taken of all Skuas,as someof the other forms may well occurhere. Field identification: Dark, immature PomarineJaegers are often mistakenfor Skuasbut when there really is a Skua,seldom if everis the reversetrue. They are big, very dark with very prominentwhite wing patcheson both upper and lower wing surfaces.The wingsare superbroad and more rounded(less pointed) than those of the jaegers. The tail is rather short. Skuashave thick "wrestler" necks and like jaegersare usuallystirring up a lot of trouble. BLACK-LEGGED KITTIWAKE, Rissatridactyla. Invasionary. Occursin vary- ing numbersfrom very late August into May and occasionallyMay to August followingflight years. Field identification:The booksare adequatebut most fail to mentionthat this specieshas a more roundedwing appearance and faster,stiffer wingbeatthan other gulls of this size. Note: Black-leggedKittiwakes with pink or reddishlegs do occur.

SABINE'S GULL, Xernasabini. Alwaysuncommon but a few are seenannual- ly in fall, late Augustto late October,and in spring,mid-April to mid-May. There is one winter record. Field identification:With any decent view, this strikingbird is obviousand there shouldbe no problem. Be awarethat Bonaparte'sGulls, which most resem- ble its flying manner,and hatching-yearBlack-legged Kittiwakes, which most re- sembleits plumage,are both more commonin the bay. ARCTIC TERN, Sterna paradisaea. Uncommon but regular mid-August to mid-Octoberusually well offshore. Very rare nearshorein springand all of the few recordsthen are from late April to 10 June. COMMON TERN, S. birundo. Fairly commonfrom late July through early Novemberand from mid-April throughMay. Often seeninside Monterey Bay as well as far offshorewhere it is occasionallyencountered in mixed flocks with Arctic Terns. FORSTER'S TERN, S. forsteri. Presentthroughout the year with strongest passagein April and May and from early Augustthrough October. A very few

128 MONTEREY PELAGICS are presentin winter and it is the only tem likely to be seen then. Forster'sare seldom seen more than a few hundred meters from shorebut there are two April recordsof the speciesseveral kilometers northwest of Point Pinos. Field identification of Sterna terns: The identification of iramatures and many timesadults is difficult andsometimes impossible under less than optimumviewing conditions. Field guides disagreeand popular concensusis usually inaccurate concerningcertain identification clues for these fine birds. The following is a summaryof bird guide descriptions,personal observations and various other printed materials, notably an account by Jean-PierreVande Weghetranslated and reprintedfrom Aves,with an addendumto includeForster's Tern (California Birds 1:29-36, 1970). Forster's Tern is the most different of these three similar species,so let us look at it contrastedagainst Common and Arctic terns, alternatelycoined "com- mic" terns (Figure 2).

Figure.2. Above, silhouette of Arctic Tern, demonstratingits short front end, small slightly decurvedbill and roundedhead. Below, Common or Forster'sTern, showingits long front end, longer, thicker bill and flatter head. 129 MONTEREY PELAGICS

FORSTER'S 1) Adult mantle pale gray, tail pale grayishyielding little contraston upper- parts (not valid in immatures). 2) Adult distinctly white outer web to outer tail feather (tail grayish). 3) Adult primarieslighter than mantle aboveand uniform light from below. 4) Winter and immature with black eyepatch to rear of eye only rarely con- nectingon nape. Like a party m•sk. 5) Immaturewith light leadingedge to inner wing (no mark). 6) Immature with buff edgesto back feathersand black tips to outer three rectrices. 7) Wingbeats(flying at ease)relatively shallowand fast. "COMMIC" 1) Mantle darker gray than Forster's,white rump and tail yield distinctback- tail contrast (as in immature Forster's). 2) Distinctly dark outer web to outer tail feather (tail white). 3) Primariesas dark or darker than mantle aboveand showingblack tipped primariesfrom below. 4) Winter and immature with eye in black, black hinderowntriangling on to nape. Like a bandannaworn black on white. 5) Immature with dark leadingedge to inner wing most noticeableas a dark shoulderereseem on perchedbirds. This mark can sometimesbe covered by body feathers. 6) Immature with brown and black edgesto back feathersand dusky tips to outer reetriees. 7) Wingbeats(flying asease) relatively rather deep andslow.

Common and Arctic Terns are superficiallyquite similarbut postureand color- ation differencesmake them easilyseparable under good viewingconditions.

COMMON 1) In flight, relatively long bill and head and short tail make that part of the bird in front of the wingsabout the samelength as that part behindthe wings. Good straightprofile view only. 2) Longbill givesthe heada long sleekappearance. 3) Looking up at the bird, little or no light can be seenthrough the flight feathersand the tail showsdark outer edges. 4) Undersideof primariesbroadly tipped with dark. 5) Adult in springslightly flushedwith light gray (hard to see). No obvious white stripeon face. 6) Adult bill usuallyorange-red and usuallytipped with dark. 7) Perched,legs (tarsi) quite long when comparedto similarlyperched Arctic Tern. 8) When perched,wing tips meet the end of the tail. 9) Dorsalwing covertsof immature gray. 10) Dark wedge on upper wing surface from tip toward base of 5th and 6th primaries.

ARCTIC 1) In flight relativelyshort bill and headand long tail makethat part of the bird in front of the wingsbarely half aslong asthat part of the bird behind the wings. 2) Shortbill giveshead rounded, 8elicate look. 130 MONTEREY PELAGICS

3) Looking up at the bird, muchlight may be seenthrough •nearly all primary and secondaryfeathers forming large trianglesof transparencyand the tail is quite white all over. 4) Undersideof primariesnarrowly tipped with blackish. 5) Adults are distinctlygray below but showa clearly definedwhite facial stripe betweenthe black cap and the gray throat. 6) Adult bill blood red with no dark tip (Commoncan get this way). 7) When perched,legs (tarsi) quite short whencompared to similarlyperched Common Terns. 8) Whenperched, wingtips fall short of the end of the tail. 9) Dorsalwing covertsof immature whitish. 10) Lack the black wedgeon upper wing surface. Three marks often consideredto be diagnosticshould be usedonly to qualify other evidence. 1) Bill color is quite variable. In springForster's is usuallyyellow-orange with a dark tip, Common is usually orange-redwith a black tip and Arctic is usually blood red to the tip. Forster's,however, can be quite red and Com- mon can be red with no black tip. Bills of all three speciesturn black in winter. 2) Apparent tarsal length dependsupon how the bird is standingand how the belly feathersare arranged. 3) The vocalizationsof these birds vary considerably,migrants seldom call and the field guide descriptionsleave most people confounded. The differ- encesin call seemto be of relative nasality with the voice of Arctic being generallyharsher and more raspy.

COMMON MURRE, Uria aalge. Quite common from July, when adultsswim into the bay with flightlesschicks, into April, when most leaveto breed on outer rocks. A few are usuallypresent through May and June. Field identification: In fall most Commonsare in full winter plumageso dark headed individuals then should be checked for Thick-billed Murres. See next species. THICK-BILLED MURRE, U. lornvia. In most of the last ten years one or two individualshave been presentjust off the mouth of the Montereyboat harbor from late August to Novemberand occasionallythrough late February. Only twice has Thick-billed been encountered more than a few hundred meters from shore. Field identification: Because in the fall most Common Murres are in winter plumage,dark headedbirds shouldbe checked. Thick-billedsaverage blacker in head and back (brownish-blackin Common) but this may be distorted by wear. The white gape mark is difficult to see and may be lackingaltogether. Better marks are the angle about mid-bill on the gonys and an evenlyrecurred culrnen. The bill appearsslightly shorter and thicker but its shape,not bulk, shouldbe noted (Figure 3). Thick-billeds more often sit on the water with the neck slightly extendedand bill pointed forwardguillemot-style but may alsoslouch the head backwardsand raisethe bill tip like a Common Murre. Another mark which is sel- dom treatedis that wherethe white and black (summerplumage only) meeton the breastthere is a rather definite high angledpeak forward on the throat of Thick- billed and it is a lower, more rounded peak in the Common. Even with all of these clues a group of us once had excellent,close looks at an individualmurre and could not assigneither name to it. For photographsand further discussion of murre identification see Yadon, California Birds 1:107-110, 1970.

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PIGEON GUILLEMOT, Ceppbuscolumba. A common breeder under wharfs in Monterey Harbor and old buildingsalong CanneryRow but numbersdrop dramaticallyin fall and the speciesis scarceuntil spring. A few, however,may be found any time of the year near shoreat HopkinsMarine Station. Seldomseen more than a few hundred meters from shore. Field identification:Juveniles and winter plumagedbirds have beenmistaken for winter plumagedMarbled Murrelets. It is not hard to do asthey canlook much more similar than the books indicate. Watch size and shapeand be surethat the white wing marksare coverts,not scapulars. HORNED PUFFIN, Fratercula corniculata. Very rare. Previousto 1976 there were only six recordsfor the Bay and five of them were of sick or deadbirds on beaches.In June 1976 at leastseven healthy birds were seen off Monterey. Most Californiarecords are for Junebut scatterinto November. It is possiblethat some of the fall recordswere actually beachedduring late summerand not discovered promptly. Field identification:The immaculatedefinition between the blackupperparts and white underpartsand the puffin bill will identify this speciessince the Com- mon Puffin (F. arctica)is most unlikely here.

Figure 3. Above,the headof a CommonMurre showing the ratherstraight cul- men and the angleof the gonysslightly posterior of mid-bill. Below,the headof a Thick-billedMurre showingthe ,evenlydecurved culmen and the angleof the gonys at mid-bill. 132 MONTEREY PELAGICS

TUFTED PUFFIN, Lunda cirrbata. Occasionallyone or two are seen on fall trips and there are a few widely scatteredrecords for the rest of the year. Field identification:The only problemis that immaturesmay look very much like the similarly sized RhinocerosAuklet. With a goodview, however,bill shape is definitive. RHINOCEROS AUKLET, Cerorbinca monocerata. Returns to Monterey Bay beginningin late July, is uncommonthrough early October,and in mid-winter builds in numbersto many thousandswhich night-rooston the calm watersbut forageby day more seaward. Most fall trips record a few individuals. The later the trip the more Rhinos. A sparsebreeder on the Farallon Islands. Field identification:See Tufted Puffin. Flyingbirds are simplylarge, mostly dark, light bellled alcidsone-third again the sizeof Cassin'sAuklet and murrelets. ImmatureTufted Puffinshave more roundedwings and largerbills.

PARAKEET AUKLET, Cyclorrbyncbuspsittacula. Not certainly identified alivefor manyyears here. Old recordsand beach corpses are from mid-November to early April Field identification:The field guidesseem to be adequate. CASSIN'S AUKLET, Ptycborampbusaleuticus. Beginsto returnto Monterey in mid-Augustand may be seenthere through fall andwinter, departing in April. It is likely that severalthousands use the bayfor a nightroost in winteras during that time drovesare often seenflying westpast Pt. Pinosat dawnwith Rhinoceros Auklets. The few summerrecords may be of foragingflocks from their nesting stronghold,the Farallon Islands. Field identification:Small, like murrelets. Uniformgray-brown above includ- ing tbroatand breast. Definitelylight bellied but nevergives the impressionof a blackand white bird as do all murreletsin winter plumage.In summerplumage, MarbledMurrelet is brownbut doesnot havean extensivelywhitish belly, has a mottledappearance and hasmore pointed wings. In flight,the wingtipsappear morestiff androunded (like tonguedepressors) than do thoseof the largeRhinoc- erosAuklet and of the murrelets. The large CrestedAuklet (Aetbia cristatella) whichconceivably could occur is darker,especially on the crown and nape, has a pale bill and is dark bellied. On the water all winter murreletsshow considerable white. Cassin's does not. MARBLED MURRELET, Bracbyrarnpbusmarmoratus. Residentbut rarely encounteredon fall trips, or any trips for that matter,from MontereyHarbor. Occasionallyone or two arein the Harbor. Mostindividuals seen within the bay are extremelynearshore from MossLanding northwest to SantaCruz. The nearest reliableplace to seethis speciesis from PigeonPoint, San Mateo County, by telescope. Fieldidentification: The fieldguides are adequate. See Pigeon Guillemot above. XANTUS'MURRELET, Endomycbura bypoleuca scrippsi. Not asuncommon asis popularlybelieved. Has been seen on MontereyBay on at leastone boat trip everyfall in the lastthirteen. Usuallyin singlesor pairsand usuallywest of the 100 fathomline, or overthe submarinecanyon but asmany as 16 havebeen seen on a singletrip andat variouspoints in the outerbay. Theearliest fall recordis 3 July and the latestis 24 October. Severalwere carefully identified near Point Pinoson 15 Februaryand 4 April 1976 and recentlya few havebeen in the vicin- ity of the FarallonIslands in spring,suggesting possible nesting. A singlesouthern Xantus'Murrelet (E. b. bypoleuca)was definitely observed 10 km northwestof Point Pinos on 2 October 1976 and is no doubt the northernmost record for that subspecies.In this form, the white from the cheeks extends up in frontof theeye andoccasionally over and behind it. For criticalidentification of Endomycbura 133 MONTEREY PELAGICS murreletssee Jehl and Bond, Morphologicalvariation and specieslimits in murre- lets of the genusEndomycbura, Transactions San Diego Society of Natural His- tory 18(2):9-24, 1975. Field identification: Uniform dark blackish-grayabove and all white below; gleamingwhite underwingssometimes flecked with a few dark feathers. Winter MarbledMurrelet always shows white scapularsand Ancienthas a grayback and upper wing coverts. Xantus' and Craveri'sMurrelets hold the head high with neck extended,not slouchedas picturedin field guides.

CRAVERI'S MURRELET, Endomycburacraveri. There are two recent rec- ords, both in August 1972. Old specimenrecords, however, extend from late August to early October. Field identification: Like Xantus' but blacker above. Underwingsappear off- white to dark gray but neverbright white. Axillarsare notably lighter than the rest of the underwing. Distribution of light and dark in the neck area may be a usablemark wherea narrowpeninsula of blackjuts downwardslightly toward the upper breast from the side of the neck as in the winter plumagedSpotted Sand- piper. Postureis like that of the Xantus' Murrelet.

ANCIENT MURRELET, Syntbliborarnpbusantiquus. Later than most alcids; the earliest date for normal arrivals is 40•tober. Numbers build in late October and November. Ancientsare fairly commonoffshore through the winter and into earlyApril. Thereis a recordof onein breedingplumage for 1 June1975. Field identification:Black of crown,face and chin (and in breedingplumage, throat) sharplydefined from grayback. The brightwhite underparts extend well up on to the neck almost forming a white collar. Bill is yellow and this is visible at a remarkabledistance. None of the other smallalcids are graybacked except Cassin'sAuklet, which is darker and much more extensivelydark on the breast and sides.

REASONABLY POSSIBLE SPECIES WANDERING ALBATROSS, Diomedea exulans. An adult female was photo- graphedsitting on shore in Sonoma County on 11 and 12 July 1967. It flew seawardon the 12th. It is possiblethat this bird was a genuinewanderer and thus is a possibleexpectee for MontereyBay. MOTTLED (SCALED) PETREL, Pterodromainexpectata. One waspicked up dead on Point Reyes Beach on 25 February 1976 (Manolis,Western Birds in press). It was a first occurrence for California; however there are several recent and old recordsfrom Washingtonand Oregon. An additionalspecimen was found beachedat San Simeon,San Luis ObispoCounty on 13 March 1976 for the sec- ond staterecord (David Ainley pets.comm.). Sincethat time, there havebeen two additionalbeached corpses reported in California,one from the south coastand one from Humboldt County. This specieswill very likely be encounteredone day off Monterey. HARCOURT'S STORM-PETREL, Oceanodromacastro. Has been reported once with convincingdocumentation as seenin Septemberoff San Diego and is a possibilityhere. WHITE-TAILED TROPICBIRD, Pbaetbonlepturus. Has been seen once in southern California and an individualtropicbird, "probably White-tailed,"was seen 12 km northwest of Point Pinos over 500 fathoms of water on 10 March 1970 by an extremelycompetent observer. 134 MONTEREY PELAGICS

BROWN BOOBY, Sula leucogaster. Recordedin waters off southernCali- fornia. One waswell describedfrom nearDavenport, Santa Cruz County 20 July 1975. Boobiesof all speciesregularly ride the mastsof ships. Someare doubtless capturedand kept alive on vesselspassing through tropical waters and later are releasedor escape. RED-FOOTED BOOBY, S. sula. An individualof this specieswas captured on the Farallon Islandson 25 August 1975 and a different bird was well seenthere on 12 Octoberof the sameyear (Huber and Lewis,Western Birds in press).The possibilitythat they were "helped"along by a northboundship does exist. KITTLITZ'S MURRELET, Bracbyrampbusbrevirostris. An individualin sum- mer plumagewashed up in southernCalifornia in Augustand there are recentrec- ordsfrom WashingtonState. For thesereasons it is includedhere as a possibility.

OTHER BIRDS USUALLY SEEN LATE SEPTEMBER THROUGH OCTOBER

Common Loon Black Turnstone PacificLoon Glaucous-wingedGull Red-throated Loon Western Gull WesternGrebe HerringGull Red-neckedGrebe Thayer'sGull Horned Grebe California Gull EaredGrebe Ring-billedGull Pied-billedGrebe Mew Gull BrownPelican Bonaparte'sGull Surf Scorer Heermann'sGull White-wingedScorer ElegantTern Red-breastedMerganser

OTHER ANIMALS WHICH HAVE BEEN SEEN ON MONTEREY BAY BIRD- ING TRIPS

Sea Otter Orca (Killer Whale) Steller's Sea Lion Sperm Shale California Sea Lion Humpback Whale Harbor Seal Minke Whale Northern Fur Seal Sei Whale Northern Elephant Seal Finback Whale PacificWhite-sided Dolphin Blue Whale Harbor Porpoise California Gray Whale Dall Porpoise Sunfish Northern Right Whale Dolphin Blue Shark Gray Grampus(Risso's Dolphin) Great White Shark Pilot Whale

135 MONTEREY PELAGICS

ACKNOWLEDGMENTS

The information herein is largelyderived from personalobservations and from information contained in records for Audubon Field Notes andA roericanBirds from the Middle PacificCoast Region. Somecritical pointsconcerning records were obtainedfromAnnotat- ed Field List Birds of Northern California by Guy McCaskieand Paul DeBenedictisand concerningplumage from Birdsof the Oceanby W. B. Alexander. The format vaguelyfollows that of PelagicBirds from the M. V. Bluenoseby Will Russelland Davis Finch. Alan Baldridge,Alan Craig, Bruce G. Elliott and Will Russellread the completemanuscript and made many helpful suggestions. Many useful ideaswere gleanedfrom conversationsover the years with Howard L. Cogswell,David F. DeSante,Jon Dunn, John Luther, Guy McCaskie,Van Reinsen,Lee Stallcup, Jon Winter and many others whilejoyfully (usually!)riding the boundingmain. Thanks to all.

Short-tailed Shearwater(Puffinus tenuirostris)about 8 km northwest of Point Pinos, Monterey County, California on 6 March 1977. Note the short bill, steep forecrown and rounded head which give this speciesmore of a "gentle look" compared to the longer bill and rather flat forecrown of the Sooty Shearwater (P. griseus). Photo by Richard W. Stallcup

Reprints with covers are available from Phil Schaeffer, 376 Greenwood Beach Road, Tiburon, CA 94920. Price:$1.50 (10 or more $1.00 each)postpaid. Make checkspayable to WesternField Ornithologists. Reprintsare not availablefrom the author.

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