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Home , Pacific ocean perch, Sebastes, Sturgeon

H. Richard Carlson and Richard R. Straty are with the Auke Bay Laboratory, Northwest and Alaska Center, National Marine Fisheries Service, NOAA, P.O. Box ISS, Auke Bay, AK 99821. Habitat and Nursery Grounds of Pacific Rockfish, spp., in Rocky Coastal Areas of Southeastern Alaska

H. RICHARD CARLSON and RICHARD R. STRATY The age that young of most rock­ species become demersal is not precisely known. Phillips (1964) cap­ tured young-of-the- darkblotched Introduction tal catches by commercial rockfish and stripetail rockfish, S. trollers indicate that echosign over saxicola, at 73-128 m (40-70 fathoms) The location of nursery grounds for these areas is composed primarily of while for off north­ juvenile Pacific ocean , Sebastes rockfish. ern . Boehlert (1977) found alutus, and most other rockfishes, Offshore, beyond most ofthe rocky that young splitnose rockfish, S. Sebastes spp., in the North Pacific areas, and several diploproa, move from surface to Ocean is poorly known. We have long other rockfish species were heavily ex­ near-bottom waters during their first suspected that the rocky, untrawlable ploited by foreign trawlers (Major and year of life in southern California. areas along the rugged coastline of Shippen, 1970) before U.S. manage­ Some Pacific ocean perch become southeastern Alaska were important ment control (in 1977) over demersal by age 1, and most probably nursery grounds for Pacific ocean continental-shelf fisheries within the adopt a demersal existence in the perch. These rough areas extend off­ 200-mile limit. Neither foreign catches nearshore coastal zone by the end of shore on the continental shelf to a nor those of U. S. research vessels con­ their first summer of life (Carlson and depth of420 m (230 fathoms) or more. ducting resource surveys in these Haight, 1976). Recent evidence sup­ A few thousand juvenile rockfishes, waters contained any early juvenile ports this idea. Twenty-five young-of­ primarily Pacific ocean perch, have stages of Pacific ocean perch or other the-year Pacific ocean perch were been trawled nearshore in coastal bays rockfish species (Lyubimova, 1965; captured in a bottom trawl in early 2 and fiords of southeastern Alaska Paraketsov, 1963; Ronholt ). October 1979 at 55-84 m (30-46 over steep slopes and ledges near Pacific ocean perch and other rock­ fathoms) in two fiords of southern rocky areas (Carlson et al. I). Inciden- fish species are ovoviviparous (live­ Baranof Island and 28 more in late bearers) and are believed to release October 1980 at 73-128 m (40-70 larvae in deeper water (Lyubimova, fathoms) off northern Chichagof 'Carlson, H. R., R. E. Haight, and K. J. Krieger. 1977. Species composition and relative 1965; Gunderson, 1971). The plank­ Island in southeastern Alaska abundance of demersal in waters of tonic larvae are transported to the (Carlson'). They ranged from 5 to 8 southeastern Alaska, 1969-77. Processed rep., nearshore waters by ocean currents cm (2 to 3 inches) FL (fork length) Auke Bay Laboratory, Northwest and Alaska Fisheries Center, NMFS, NOAA, P.O. Box (Lisovenko, 1964), a characteristic of and had just begun formation of the ISS, Auke Bay, AK 99821. the life history of many marine first annulus, marking the end oftheir (May, 1974), e.g., Dover , Micro­ first growing season. stomus pacificus; rex sole, Glypto­ The lack of young rockfish in off­ cephalus zachirus; and petrale sole, shore catches and their occurrence in ABSTRACT-During late July 1978 we Eopsettajordani (pearcy et al., 1977); catches at several nearshore locations used a small submarine to explore the English (lemon) sole, Parophrys led Carlson and Haight (1976) to rugged rocky substrate along the of vetulus (Ketchen, 1956); and dark­ hypothesize that the nearshore, rocky­ southeastern Alaska to depths of nearly blotched rockfish, S. crameri; canary 240 m (/30 fathoms). The extensive bottom coastal areas and adjacent boulder fields and pinnacle-studded bot­ rockfish, S. pinniger; and rosethorn bays and straits of Alaska are nursery tom were populated mostly by rockfish, rockfish, S. helvomaculatus (Richard­ areas for Pacific ocean perch. Adult Sebastes spp., ofseveral species anda wide son and Laroche, 1979). Pacific ocean perch reside in and range of sizes. This untrawlable zone is a nursery area for rockfish, and dense schools ofthousands ofsmall 6-8 cm (2.5-3 inch) red rockfISh were sighted at 90-100 m 'Carlson, H. R. Evidence for an early demersal existence of young-of-the-year Pacific ocean (49-55 fathom) depths over crevices and 'Ronholt, L. L. 1979. Northwest and Alaska perch in southeastern Alaska waters. Unpubl. cover. Fish were less abundant in similar Fisheries Center, NMFS, NOAA, 2725 Montlake manuscr. avail. Auke Bay Laboratory, North­ surveys of protected waters of a bay and Blvd. East, Seattle, WA 98112. Personal com­ west and Alaska Fisheries Center, NMFS, fiord adjacent to the coastal sites. mun. NOAA, P.O. Box ISS, Auke Bay, AK 99821.

July 1981,43(7) 13 along gullies and canyons farther , seaward on the outer continental shelf (Major and Shippen, 1970). NORTH )

In July 1978, we used a small PACIFIC \' submersible to search for young \ t1t Pacific ocean perch and visually OCEA survey fish in two rocky-bottom \ I .~ coastal areas exposed to open-sea conditions and in an adjacent bay and {, s strait protected from open-sea condi­ \ , tions in the northern part of south­ eastern Alaska. This paper presents PORTLOCK our observations of the behavior and HARBOR habitat of young rockfish believed to be Pacific ocean perch, and describes the behavior and habitat of several other species of rockfish at various life stages. Methods The two exposed, rocky-bottom coastal areas were off Cape Cross on Yakobi Island and offPortlock Harbor on Chichagof Island in the northern part of southeastern Alaska (Fig. 1). The two protected areas were approx­ imately 3 km (2 miles) inside Lisianski Strait in the Cape Cross vicinity and 1.6 km (1 mile) inside Portlock Har­ bor near its southern entrance. These four areas were selected as being Figure I.-Sites of surveys of communities off southeastern representative of the coastal bottom Alaska, July 1978. topography of the northern part of southeastern Alaska after we con­ ducted echo-sounding surveys in May 1978 in this region. in this region, could render the powered, carries two persons, and can The areas off Cape Cross and submersible operation hazardous. operate down to 305 m (167 fathoms) Portlock Harbor were exposed to Water visibility was outstanding on and operates at 1.8-5.5 km/h (1-3 open-ocean sea and swell conditions, open-coast surveys and ranged from knots) for 2-4 hours. and the water was much clearer than 10 to 23 m (33 to 75 feet). On the The transects at exposed coastal inside Lisianski Strait and Portlock surveys inside fiords and bays, locations were plotted across uneven Harbor where waters were not as sub­ visibility was much less, being only bottom located on earlier echo­ ject to oceanic influence and heavy 2-7 m (6-23 feet). sounding surveys. These transects seas and swells. The greater turbidity The submersible Nekton Gamma were <=6 km (3.7 miles) long and of the protected areas may be due to (Fig. 2), chartered from General generally ran from shallow to deep material suspended in the water from Oceanographics4 of San Diego, water. We surveyed single transects surface runoff and streams, and Calif., by NOAA's Manned Undersea <=2 km (1.2 miles) long across the restricted circulation with the adja­ Science and Technology Program Of­ sites in Lisianski Strait and Portlock cent, clearer offshore waters. fice, was made available to the Harbor. We were fortunate to have unusual­ authors from 21 to 28 July 1978 to It was almost impossible to adhere ly good weather during the survey conduct surveys beyond scuba depths to the coastal transects because of the period. Seas off the coast generally (>40 m or > 130 feet). The submers­ extreme uneveness of the bottom (Fig. ranged from a gentle ocean swell to I ible is 5 m (16 feet) long, battery- 3, 4). Navigating steep pinnacles and m (3 foot) swells, which permitted sheer ledges would have required fre­ launching and retrieval of the sub­ quent, rapid changes in depth largely 'Reference to trade names or commercial firms mersible without incident. Moderate does not imply endorsement by the National beyond the capabilities of the sub­ to heavy seas, which frequently occur Marine Fisheries Service, NOAA. mersible at its normal cruise speed of

14 Marine Fisheries Review 3.7 km/hour (2 knots). After some experience, we decided to cruise along the bottom for short distances and stop frequently to make observations when the submersible path was ­ structed by abrupt changes in bottom topography. We followed transects across the center of the two inside protected sites without difficulty. We identified in situ the types of substrate and fish species, estimated their sizes and relative abundance, and noted schooling behavior and reaction of fish to the submersible. Descriptions of the fish, their habitats, and behavior were recorded on a small portable tape recorder. Fish and their habitats were photo­ graphed in color with an externally mounted 35 mm Model 372 camera with flash. The camera was operated by the submersible pilot as subjects of interest came into view. We also used a portable video cassette Figure 2.-The research submarine Nekton Gamma used to survey demersal camera to obtain black-and-white fish in southeastern Alaska.

Figure 3.-Bottom topography of the survey area as charted seaward from Portlock Harbor.

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Figure 4.-Bottom topography of the survey area as charted seaward from Cape Cross.

July 1981, 43(7) 15 Figure 5.-Young rockfish over part of a steep, rocky pinnacle. Figure 6.-Young rockfish and rugged, rocky substrate.

Figure 7.-Several rockfishes over part of an extensive Figure 8.-A large (:>2 m) wolf- moves slowly over a boulder field. A young is in the extreme boulder field. lower right, a to the right, and small unidenti­ fied rockfish to the upper center and upper left.

documentation of fish and their (Fig. 7, 8) interspersed with areas of darker blotching above the lateral line behavior. gravel-shell that were deeply furrowed, and generally had a slender body pro­ apparently by wave action. file. They had no heavy spines evident Rockfish Nursery Area Marine life in the rocky areas was in the head region; no black margin Our most significant findings came abundant and diverse. Rockfish of on fins; no distinct stripes, spots, or from the surveys offshore from Port­ several species and wide size-range bars; and no disproportionate feature lock Harbor and Cape Cross (Fig. 1). predominated. Clouds of thousands such as large eye, high dorsal fin, etc. Here we found what appeared to be of 6-8 cm (2.5-3 inch) reddish rockfish Larger Pacific ocean perch have a nursery grounds for young rockfish. (Fig. 9), which we believe are Pacific pronounced symphyseal knob or pro­ These schools were at 90-100 m (49-55 ocean perch, extended as far as the jecting lower jaw, but this is not well fathoms), over a bottom that varied limits of visibility (as much as 18 m or developed in the young. from ragged, steep, rocky pinnacles 60 feet) in all directions. These small We saw other fishes in the rocky (Fig. 5, 6) to extensive boulder fields rockfish were reddish with some offshore areas (Table 1). Large

16 Marine Fisheries Review few large Pacific , Hippo­ glossus stenolepis; , Ophiodon elongatus; kelp greenling, Hexagram­ mos decagrammus; and wolf-, Anarrhichthys ocellatus. Small , rockfish, , and either dusky rockfish, S. ciliatus, or , S. melanops, were observed by scuba divers at 9-18 m (30-60 feet) inshore at Cape Cross (Barr') at the same time as our observations; there­ fore, the nursery area probably extends into subtidal shallows. Invertebrates in rocky offshore areas were not sparse but generally lacked variety. Frequently encoun­ tered were anemones, Metridium senile (Fig. II); hydrocorals, Allopora sp.; sea stars (i.e., Crossaster pap­ Figure 9.-Part of a dense school of young, 6-8 em, red rockfish (believed to be posus, Henricia sp., Solaster sp.); Sebastes alutus) that extended to the limits of visibility over a rugged, rocky basket stars, sp.; boulder field. Gorgonocephalus brittle stars; sponges; and bryozoans. The two submersible surveys inside bays and fiords with entrance sills near the open coast, in Lisianski Strait and Portlock Harbor, covered depths of 18-240 m (10-130 fathoms). We found steep, rocky ledges that ex­ tended from nearshore and were over­ laid with sand-shell at shallower depths and sand-silt at deeper depths. At deeper depths, we found a few isolated boulders and smooth rocky outcrops. At the inside sites, rockfish were not as abundant and fewer spe­ cies were sighted. Most ofthe fish were types that lay in contact with the substrate, such as , skates, sculpins, and poachers. The only rockfishes sighted were a school of mixed large and small dusky rockfish in 18 m (10 fathom) shallows and isolated large individual , quillback rockfish, and Figure IO.-A large (I m) lingcod Oeft) and several yelloweye rockfish photographed over a portion of sand-shell substrate adjacent to rocky zones. Pacific ocean perch at deeper levels, Furrows in the sand (upper left) were apparently caused by surge action down to :>183 m (l00 fathoms). We also saw a ':Xl-IOO m (49-55 fathoms). These rockfish were attracted to the submarine and few large Pacific , Gadus macro­ examined it closely. cephalus, and large and small walleye , Theragra chalcogramma. Invertebrates were abundant and diverse at inside sites. Below 91 m (50 yelloweye rockfish, S. ruberrimus maliger; rosethorn rockfish; widow fathoms), pink shrimp, Pandalus (Fig. 10), were abundant. Also pres­ rockfish, S. entomelas; rougheye ent were yellowtail rockfish, S. rockfish, S. aleutianus; tiger rockfish, flavidus; , S. S. nigrocinctus; and silvergray 'Barr, L. P.O. Box 361, Auke Bay, AI( 99821. nebulosus; quillback rockfish, S. rockfish, S. brevispinis; as well as a Personal commun.

July /981, 43(7) 17 range and swam off. Large halibut appeared curious but cautious and could not be approached closely, Schools of rockfish other than yellow­ eye rockfish appeared to behave nor­ mally and paid no particular notice to the submersible, unless we moved directly towards a school and then they moved off. Conclusions The rocky areas, exposed to open­ sea conditions, that we surveyed are a haven or nursery ground for young rockfishes including Pacific ocean perch. This finding supports the hypothesis by Carlson and Haight (1976) that juvenile Pacific ocean perch inhabit these areas where cover Figure I I.-Large white anemones, Metridium senile, growing on boulders, and protection are afforded by cracks provide shelter for small rockfish, Sebastes sp. and crevices in and under rocks and ledges and among sessile invertebrates such as the anemone Metridium senile.

Table 1.-Fishes observed during submersible surveys off the northwestern coast of Chichagof Island, Alaska, July 1978. Near-bottom marine life differed in the two types of areas surveyed. In the Common name SCientific name Common name Scientific name exposed outer coastal areas, fishes Rougheye rock fish Sebastes aleutianus Walleye pollock Theragra chalcogramma predominated, primarily rockfishes of Pacific ocean perch Sebastes alutus Hippoglossus stenolepis Silvergray rockfish Sebastes brevispims Flathead sole Hippoglossoides elassodon several species and life stages. In con­ Dusky rockfish English sole Parophrys vetulus Sebastes enlomelas Dover sale Microstomus pacilicus trast, in the protected waters of an Yellowtail rockfish Sebastes /lavidus Big skate Raja binoculata adjacent coastal fiord and bay, inver­ Rosethorn rockfish Longnose skate Raja rhina Quillback rockfish Sebastes maliger Unidentified sculpIn Trig/ops sp. tebrates predominated, primarily China rockfish Sebastes nebulosus Blackfin sculpin Malacocottus kincaidl shrimp, small , snails, sea stars, Tiger rockfish Sebastes nigrocinctus poacher Agonus acipenserinus Yelloweye rockfish Sebastes ruberrimus Blackfin poacher Bathyagonus nigripinnis and anemones. Many species of inver­ Wolf-eel Anarrhichlhys aeellatus Alaska eelpout Bothrocara pusilium tebrates and most life stages were Lingcod Ophiodon etongatus Oncorhynchus kisutch Kelp greenling Hexagrammos decagrammus Pacific sand lance Ammodytes hexapterus represented; fish were few in number Searcher Bathymaster signatus Ratfish Hydrolagus colliei Gadus macrocephalus and variety.

Literature Cited Boehlert, G. W. 1977. Timing of the surface­ to-benthic migration in juvenile rockfish, borealis, were particularly abundant, frightened by or attracted to the , off southern California. Fish. BuU., U.S. 75:887-890. and at least four other species of submersible with its lights and strobes Carlson, H. R., and R. E. Haight. 1976. Juve­ shrimp were seen, including sidestripe that flashed intermittently. Notable nile life of Pacific ocean perch, Sebastes exceptions were large yelloweye rock­ alutus. in coastal fiords of southeastern shrimp, Pandalopsis dispar. , Alaska: Their environment, growth, food nudibranchs, and gastropods were fish, which appeared to be attracted habits, and schooling behavior. Trans. Am. common, as were sea stars and ane­ to the submarine and actually followed Fish. Soc. 105:191-201. it around and cruised in close to peer Gunderson, D. R. 1971. Reproductive patterns mones. Many small snow crabs, of Paci fic ocean perch (Sebastodes alutus) off Chionoecetes sp., 1-4 cm (0.5-1.5 in portholes. They appeared intrigued and and their inches), were seen in or near the with the submersible. In one instance relation to bathymetric distribution and seasonal abW1dance. J. Fish. Res. Board deepest part of Lisianski Strait at hundreds of these large, reddish, 7-10 Can. 28:417-425. 227-238 m (124-130 fathoms). kg (15-22 pound) fish trailed behind Ketchen, K. S. 1956. Factors influencing the the submersible in a long column. survival of the lemon sole (Parophrys vetulus) in Hecate Strait, British Columbia. J. Fish. Large wolf-eels usually moved Reaction of Res. Board Can. 13:647-693. slowly away and appeared to beat a Lisovenko, L. A. 1964. Distribution of Far­ Fishes to Submersible eastern red fish Sebastodes alutus Gilbert in dignified retreat. Large lingcod briefly the Gulf of Alaska. [In Russ.] Tr. Vses. Most rockfish did not appear looked the submersible over at close Nauchno-issled. lnst. Morsk. Rybn. Khoz.

18 Marine Fisheries Review Okeanogr. 53 (Izv. Tikhookean. Nauchno­ 85-111. Avail. Nat!. Tech. Inf. Serv., Spring­ eastern part of the Pacific Ocean, Part I, p. issled. Inst. Morsk. Rybn. Khoz. Okeanogr. field, VA 22151, as IT 67-51206.) 319-327. Avai!. Nat!. Tech.lnf. Serv., Spring­ 52:223-231. (Trans!. by Isr. Prog. Sci. Major, R. L., and H. H. Shippen. 1970. Synop­ field, VA 22151, as IT 67-51203.) Trans!., 1%8. In P. A. Moiseev (editor), sis of biological data on Pacific ocean perch, Pearcy, W. G., M. J. Hosie, and S. L. Richardson. Soviet fisheries investigations in the north­ Sebaslodes alulus. U.S. Dep. Commer., Nat!. 1977. Distribution and duration of pelagic life eastern part of the Pacific Ocean, Part 3, p. Mar. Fish. Serv., Circ. 347, 38 p. of larvae of Dover sole, Microslomus paciji­ 217-225. Avail. Nat!. Tech. Inf. Serv., Spring­ May, R. C. 1974. Larval mortality in marine cus; rex sole, G/yplocephalus zachirus; and field, VA 22151, as IT 67-51205.) fishes and the critical period concept. In J. H. petrale sole, Eopsella jordani, in waters off Lyubimova, T. G. 1%5. The main stages in the S. Blaxter (editor), The early life history of Oregon. Fish. Bull., U.S. 75:173-183. life cycle of Pacific ocean perch Sebasles fish, p. 3-19. Springer-Verlag, N. Y. Phillips, J. B. 1964. Life history studies on ten alulus Gilbert in the Gulf of Alaska. [In Paraketsov, I. A. 1963. On the biology of species of rockfish ( Sebaslodes). Calif. Russ.] Tr. Vses. Nauchno-iss1ed. Inst. Morsk. Sebaslodes alulus in the . [In Dep. Fish Game Fish Bull. 126, 70 p. Rybn. Khoz. Okeanogr. 58 (izv. Tikhookean. Russ.] Tr. Vses. Nauchno-issled. Inst. Morsk. Richardson, S. L., and W. A. Laroche. 1979. Nauchno-issled. Inst. Morsk. Rybn. Khoz. Rybn. Khoz. Okeanogr. 48 (Izv. Tikhookean. Development and occurrence of larvae and Okeanogr. 53 :95-120). (Trans!. by Isr. Prog. Nauchno-issled. Inst. Morsk. Rybn. Khoz. juveniles of the rockfishes Sebasles crameri, Sci. Trans!., 1%8. In P. A. Moiseev (editor), Okeanogr. 50:305-312). (Trans!. by Isr. Prog. Sebasles pinniger, and Sebastes helvo­ Soviet fisheries investigations in the north­ Sci. Trans!., 1968. In P. A. Moiseev (editor), maculatus (Family ) off eastern part of the Pacific Ocean, Part 4, p. Soviet fisheries investigations in the north- Oregon. Fish. Bull., U.S. 77:1-46.

July 1981,43(7) 19