Ecosystems, Anchorage, Alaska
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llbrary U.S. Fi , c11 . i 1 RECONNAISSANCE OF BREEDING MARINE BIRDS AND MAMMALS IN THE LATAX ROCKS AND PERENOSA --- I BAY-SHUYAK-AFOGNAK ISLM'DS by .... - Key; Words: Marine Birds, Raptors, Marine Mammals, Afognak and Shuyak islands ARLIS ALASKA RESOURCES LIBRARY & INFORMATION SERVICES 3150 C STREET, SUITE!()() ANCHORAGE, ALASKA 99503 I ! 0 I I 0 0 1.!) I 1.!) I r et) I ! : C') November 1983 2 A~a::-.a i.~ational Intere:st I..: .. :J•_Is Conservation Act (ANILCA Sec. 1927) included all public lands, .including sub~erged lands, adjacent to the exterior boundary of the former "Afognak Forest and Fish culture Reserve" as part of the Alaska Maritime NWR. The Act further grants the Koniag Village Corporation timber rights on Discoverer and Delphin islands, provided that management and harvest of such timber be only in accordance with management plans developed jointly by Koniag and the Fish and Wildlife Service. The Latax Rocks-north of Shuyak Island also were included in the Maritime Refuge along with the nearby Barren Islands. - .·I ~!though the Barrens have been studied extensive~y since 1974- (Bailey 1976, Manual 1980), no refuge biologists have visited the Latax Rocks 25 km to the south. The Latax Rocks and Perenosa Bay were visited by dory in 1976 by Office of Biological Services personnel, but no landing was made (Sowls ~ £l. 1978). The Latax Rocks are composed of mainly three small (4 ha) rocky islets 2 km north of- Dark Island- (Figure 1). The islands in Perenosa Bay on the north side of Afognak range from rocks and tiny grassy stacks to Discoverer Island, densely forested and about 100 ha in size (Figurel). HETHODS We were flown in a De Havilland Beaver with floats from i i / 3 I I I Figure 1. Latax Ro7ls and Perenosa Bay andjVicinity. I I I / I I + I ·c... 0 I / I I I· I I + ' I ~- / "(..., ;~ ;:. ~ I I 3omer to Carry Inlet OL From he~e volunteer assistant Nina Fa~st a~~ I proceeded to Dark! Island, La tax Rocks, and on to Pere:1osa Bay with a 13-fpot Zodiac and two 25 hp outboards. We were picked up at Port Williams on the south side of Shuyak on 19 ,July. The north and east sides of Shuyak Island and offshore islands, including the Perevalnie and Sea Otter i~lands, and both sides of Shuyak strait also were I surveyeid enroute to Port Williams. I Colonie's were indicated on 1:63,360 USGS mapn. Po pula t:ion estimates for kittiwaj{es, gulls, and cormorants were based on nest counts. Numbers of ..... - puffin~ were derived from estimates of burrow numbers and numbers of birds observed around islancs. Estimates of guilllemots represent numbers sighted, and like ' puffin~, should be regarded as minimal. All marine mammals, raptors, and passerines were documented along with notes on vegetation and other I significant features on different islands. I RESULTS AND DISCUSSION Island:Accounts ~ Island. Dark Island, covering roughly 160 ha and r~sing to 35m (Figure 1), is dominated mainly by beach 1 rye (Elymus arenarius.. mollis), bluejoint (Calamagrostis canadensis), (~happsia s~.), and other grasses and sedges (Carex spp.) Clumps of wind-blown .') Sitka spruce (Picea sitchensis) are widely sc~.~t~r~C on the island. Crowberry (Empetrurn nigrum), Sedum rosea, Achellia ~' Sanauisorba stjpulat;., and other moist tundra vegetation predominate on the inland ridges of this island, which appears to be ownec by the State of Alaska. Ponds on the north end were filled with yellow pond lily (Nunhar polysepalum) • With the possible exception of a few pairs of Mew Gulls (Larus canus), no seabirds nested on Dark Island in 1983 (Table 1), which because of its close proximity to Shuyak is frequented by brown bears (Drsus ~~) • However, 267 Glaucous - winged Gulls (k Glauces-c;:~) .·• ··.· -and 80 Tufted Puffins (Ftatercula cirrhata) nested on the -island in 1976 (Sowls ~ ~ 1978); these colonies evidently were eliminated by bears. Approximately 100 Mew Gulls used the ponds along with Red-throated Loons (Gavia stellata), Red-breasted Merga~sers (Mergus serrator), Northern Pintails (~ acuta), Mallards (~ platyrhynchos), and two broods of Greater Scaup (avthya mar_..i..la). Four Parasitic Jaegers (Stercorarius parasiticus) were sighted, but no nest was found. Twenty Black Oystercatchers (~ bachmani) and Least Sandpipers (Calidris minutilla) and Black Turns tones (Arenaria melanocephala) were observed. Northwestern Crows (Corvus caurinus) nested in spruce clumps; Song Sparrows (Melospiza melodia) and Savannah Sparrows (Passerculus sandwichensis) were the primary I ,j,J, I. l•:till11111ll'd 'lll"l~t~dl'llg Jllllrti or llellhlrdti IH'IWI'I'Il lllll'k l~illllld tllld l't'l"l'lllllill llily,,i\lop,nllk' ·- :illllliYIIk ltililll·d, i\liJ:iiUI . __ __::~..::====.::.:.::::::.=:::::====.::.::.:.:::.:.::=:::.::::.:.:.==...:.:...::-.:.:.-:.:·_::::..::.:=~=-.:=:.=.=..::.:=.::::::-:_:~ ..:.::~=- .::._.::.==:::.:.:......:..:.::~::~~=:::::·.. :.___. :.:.: .. --~.-4- ............ ~- :·. =~·.:.:. ::.-.-.:... --- .. - -· ~- --. -· --- -·- . -- ~ ·- 4 • r-i I I <IJ .IJ 0 l----l -- ·==~=- ----~--=------...:.._ __:._ ____ ~---------- -··- .. ,,.,,.J,J ,. ·creHI l.!d I: • • t I ill I 1: <I Ill: ') 5 :'.·1• ·.i•: Curmorunt 5 ]2 130 10 157 i:,-,1-Faced Cormorant 150 150 Hlack Oystercatcher 2 2 2 15 21 Parasitic Jaeger P? C I ;JIIl'lliiii-W lll!',t' r· Cui I ') 'i () ~1L~w Cull. P'! Ill ;1ck-l egged 20 20 K_i ttiwake Pigeon Guillemot 5 10 J.O 25 Ancient Murrelet P? P,u~akeet Auklet 5 5 10 5 ?1 ·w '1'11! tl'd J'uii:Ju :!() I t Hl -"--'"-=·--=----=·--=--.:...=· =---=-=---=----"-'--=--=--"'--=-'"·=···=-·--=--=- =~-"'-'""-'-' ·=---·=· -=-----------~- - -- -- ... - .. ---~'----'-'----'---'-'-------=--- ----- ~------ .. -----'--"---- ---'- -~--- --- ------------ -- - --' '----'-"'-'--'--'---'-'---·"---'--'---'---'--~--------'---------'-------- --- ----·--- -- ------ --- - - 1 0 T. I( ·•.:.::===========~5==~4~2===~l~~4~9~====:::!2~2~o~===3~7~=:!::1!::.:7 :~s ===~93::2~================= P-present C-common A-abundant pa.s .Se r 1ir:e species using the is L I - Arc':ic1 foxes (Alooex laaoous) were placed on Dark Island ear2.y 'in the 1900's for fur farming but later reportedly we~e removed by trapping. The ground squirrels parr vi) currently present undoubtedly origiriated from the fut farming era. Latax Rocks. The southernmost of the three islets ("Tax" bench mark) is the only one high enough to suppo~t beach rye and other terrestrial vegetation. An esti3~ted 5000 sea lions (Eumatopias jubata) were hauled out o~ "Tax" Island; about 200 more were on each of the . ' " +- 1S.-.e ... s to t~e northeast (Table 1). ~~o pups were ··.· spo~t~d, but bear tracks were present in the midst of the 1slet. Though no remains of sea lion pups were found~ pups would be easy prey for bears; adults te~po~arily leave the rookery when sust2ined disturbance OCC'..:rS. Few pups would be expected here, as the Latax Rocks ~ are regarded as a haulout area rather than as a I I rookery (Caulkins and Pitcher 1982). Generally sea lion ! bear i rookeiies or haulouts are far fro8 brown i l ! I I popul~tions or are inaccessible. Brown bear predation i on seabirds is common along the Alaska Peninsula (pers. I i I' obs.)( but this is the only place I am aware of where I they :evidently invaded a sea lion haulout. In 1976, I nearly 3900 sea lions were estimated in the Latax Rocks (Dick; and Nelson 1976) Caulkins and Pitcher (1982) recorded' less. I i , I ' :. i ! ' j I ! I 8 ~he Latax 2ocks also support a small assemblage of - seabirds. We found over 100 Glaucous-winged Gulls' and two abandoned nests, scattered puffin burrows in the grass on the eastern end of "Tax" Island, 20 pairs of Black-legged Kittiwakes (Rissa u.li~actvla), and several Parakeet Auklets (Cyctorrhynchus gsittacula) offshore. An auklet flew into a rock crevice 1 indicating probable nesting; a Horned puffin (FrcJtercula cornicu1ata) incubating an egg in a crevice was noted, but the few burrows checked appeared abandoned. Many Fork-tailed Storm-Petrels were in the tide rips around the Latax Rocks, but no small burrows were detected, and no ••. - nocturnal nesting seabirds were heard while camped on nearby- Dark Island. Over 300,000 storm-petrels nest in the Barren Islands {Manuwal 1980). In 1976 nearly 800 gulls reportedly nested on the three Latax Rocks (Sowls ~ ~. 1978) , but since this count was made from a dory, it was based on the number of adults observed rather than on an actual nest count. Most of the gulls in this area are merely loafing, and it is difficult to see how these tiny, low islets, much of which are awash in storms, could support 400 pairs of gulls in addition to several thousand sea lions. In 1976, 150 kittiwakes and Tufted Puffins were recored on "Tax" Island, and Parakeet Auklets also were noted then. Because of severe tide rips we djd., not visit the two smaller islets northeast of "Tax", but from the air and 9 from the wate.:.: :.<:..;lL:i t!Jef :.q?pearc.:.. -'- -. too low and barren to support any significant colony of birds, and no vascular plants were evident. The only Pigeon Guillemots (Cepphus columba) we saw in the area were three off Dark Island, compared to 70 reported in the Latax Rocks in 1976 (Sowls ~ al. 1978) • Thousands Qf shearwaters (Poffinus sp.) were visible in Shelikof Strait. Other observations in the Latax Rocks included Black Oystercatchers, Rock Sandpipers (Calidris ptilocnemis),· Bald Eagles (Haliaeetus ~cocephalus), Song Sparrows, - and 25 sea otters (Enhydra lutris). - ~ Otter Island. This small grassy island lying 10 km east of Andreen Bay on the east side of Shuyak Island has the only sizeable seabird colony in the areas surveyed. After circumnavigating the island we began searching for burrows of nocturnal nesters ashore and were about to set up camp when we discovered a bear, necessitating a hasty departure from the island. Twenty Ancient Murrelets (Synthliborampbus anti~uus) were on the water about 3 km to the west; so it is very possible that this species and perhaps storm-petrels use the island.