NOAA Professional Paper NMFS 9 U.S. Department of Commerce December 2007 Genetic and morphological identification of pelagic juvenile rockfish collected from the Gulf of Alaska Arthur W. Kendall Jr. Christine Kondzela Zhuozhuo Li David Clausen Anthony J. Gharrett U.S. Department of Commerce NOAA Professional Carlos M. Gutierrez Secretary National Oceanic Papers NMFS and Atmospheric Administration Vice Admiral Scientific Editor Conrad C. Lautenbacher Jr., Dr. Adam Moles USN (ret.) Under Secretary for Associate Editor Oceans and Atmosphere Elizabeth Calvert National Marine Fisheries Service, NOAA National Marine 17109 Point Lena Loop Road Fisheries Service Juneau, Alaska 99801-8626 James W. Balsiger Acting Assistant Administrator for Fisheries Managing Editor Shelley Arenas National Marine Fisheries Service Scientific Publications Office 7600 Sand Point Way NE Seattle, Washington 98115 Editorial Committee Dr. Ann C. Matarese National Marine Fisheries Service Dr. James W. Orr National Marine Fisheries Service Dr. Bruce L. Wing National Marine Fisheries Service The NOAA Professional Paper NMFS (ISSN 1931-4590) series is published by the Scientific Publications Office, National Marine Fisheries Service, The NOAA Professional Paper NMFS series carries peer-reviewed, lengthy original NOAA, 7600 Sand Point Way NE, research reports, taxonomic keys, species synopses, flora and fauna studies, and data-in- Seattle, WA 98115. tensive reports on investigations in fishery science, engineering, and economics. Copies The Secretary of Commerce has of the NOAA Professional Paper NMFS series are available free in limited numbers to determined that the publication of government agencies, both federal and state. They are also available in exchange for this series is necessary in the transac- tion of the public business required by other scientific and technical publications in the marine sciences. Professional Papers law of this Department. Use of funds are published online in PDF format at http://spo.nmfs.noaa.gov for printing of this series has been ap- proved by the Director of the Office NOTICE: This series was established in 2003 to replace the NOAA Technical Report of Management and Budget. NMFS series. NOAA Professional Paper NMFS 9 Genetic and morphological identification of pelagic juvenile rockfish collected from the Gulf of Alaska Arthur W. Kendall Jr. Christine Kondzela Zhuozhuo Li David Clausen Anthony J. Gharrett December 2007 U.S. Department of Commerce Seattle, Washington Suggested reference Kendall, Arthur W., Jr., Christine Kondzela, Zhuozhuo Li, David Clausen, and Anthony J. Gharrett. 2007. Genetic and morphological identification of pelagic juvenile rockfish collected from the Gulf of Alaska. NOAA Professional Paper NMFS 9. 26 p. Online dissemination This report is posted online in PDF format at http://spo.nmfs.noaa.gov (click on Professional Papers link). Purchasing additional copies Additional copies of this report may be available for purchase in paper copy or microfiche from the National Technical Information Service, 5285 Port Royal Road, Springfield, VA 22161; 1-800-553-NTIS; http://www.ntis.gov. Copyright law Although the contents of the Professional Papers have not been copyrighted and may be reprinted entirely, reference to source is appreciated. Proprietary products The National Marine Fisheries Service (NMFS) does not approve, recommend, or endorse any proprietary product or proprietary material mentioned in this publication. No reference shall be made to NMFS, or to this publication fur- nished by NMFS, in any advertising or sales promotion which would indicate or imply that NMFS approves, recommends, or endorses any proprietary product or proprietary material mentioned herein, or which has as its purpose an intent to cause directly or indirectly the advertised product to be used or purchased because of this NMFS publication. Abstract—Pelagic juvenile rockfish (Se- Genetic and morphological identification bastes spp.) collected in surveys designed to assess juvenile salmonids and other species of pelagic juvenile rockfish collected in the Gulf of Alaska in 1998 and 2000–2003 provide an opportunity to document the oc- from the Gulf of Alaska currence of the pelagic juveniles of several species of rockfish. Often, species identifica- Arthur W. Kendall Jr.1, Christine Kondzela2, tion of rockfish is difficult or impossible at 3 2 3 this stage of development (~20 to 60 mm), Zhuozhuo Li , David Clausen , and Anthony J. Gharrett and few species indigenous to Alaska waters 1 AJALA Enterprises have been described. Use of mitochondrial 635 Wanapum Drive DNA markers for rockfish species allowed LaConner, WA 98257 unequivocal identification of ten species (S. Email: [email protected] aleutianus, S. alutus, S. borealis, S. entomelas, S. flavidus, S. melanops, S. pinniger, S. proriger, S. 2 Auke Bay Laboratories reedi, and S. ruberrimus) in subsamples from Alaska Fisheries Science Center the collections. Other specimens were ge- National Marine Fisheries Service netically assignable to groups of two or three National Oceanic and Atmospheric Administration species. Sebastes borealis, S. crameri, and S. reedi 17109 Point Lena Loop Road were identified using morphological data. Juneau, AK 99801 Combining genetic and morphological data 3 School of Fisheries and Ocean Sciences allowed successful resolution of the other University of Alaska Fairbanks species as S. emphaeus, probably S. ciliatus 11120 Glacier Highway (although S. polyspinis cannot be totally Juneau, AK 99801 ruled out), and S. polyspinis. Many specimens were initially morphologically indistinguish- able from S. alutus, and several morpho- logical groups included fish genetically identified as S. alutus. This paper details the characteristics of these pelagic juveniles to facilitate morphological identification of these species in future collections. Introduction and fisheries management efforts into pelagic juveniles, and some include restricting or closing fish- species remain in the water column Rockfishes (Sebastes spp.) form ing and creating marine reserves for several months, while others set- an ecologically and economically to rebuild populations. Assessing tle to the bottom or to kelp within important group of fishes in the the size of the populations at vari- a few weeks (Moser and Boehlert, Northeast Pacific (Love et al., ous times in their life histories is 1991). The pelagic juvenile stage, 2002). They are quite diverse taxo- required to evaluate the effective- which may last for over six months nomically with about 70 species ness of fisheries management ef- (Boehlert, 1977), is ecologically occurring in the region and up to forts. Such assessments and other and morphologically distinct from 30 in one location, and also eco- fisheries research on these fishes the generally demersal adult phase, logically diverse with, for example, are hampered by the inability to and may be important in determin- some species occurring in tidepools identify their planktonic larval and ing year-class strength. and others at depths >1000 m. As pelagic juvenile stages in field col- Sampling for pelagic juvenile adults, most species are demersal lections. Adult morphological char- rockfish off central California pro- and associate with hard bottoms, acters are not fully developed in vides an index of year-class strength but some are semi-pelagic. All spe- pelagic juveniles; however, genetic for several species (Ralston and cies are viviparous, with individuals characters, which persist through- Howard, 1995; Ralston and Ianelli, of some species yearly bearing up out life history stages, and distinct 1998; Sakuma et al., 2006). Also, to 105 yolk-sac planktonic larvae. pigment and other morphological relationships between ocean con- Some species are among the long- features unique to the juvenile life ditions and the abundance and est living fishes, reaching ages of history stage can be applied to spe- growth of juvenile rockfish have over 100 years. Severe overfishing cies identification of juveniles. been documented through these has reduced some species to less After a larval stage of a few weeks, surveys (Woodbury and Ralston, than 10% of their virgin biomass, many rockfish species transform 1991). Such studies are predicated 2 Professional Paper NMFS 9 on the ability to identify the rockfish juveniles that are same specimens. Such analyses are needed to develop collected in these surveys. Although morphological diagnostic morphological criteria to distinguish the spe- identification criteria for juveniles have been developed cies of field-collected pelagic juveniles of Sebastes spp. for many rockfish species that occur off California (Lai- dig and Adams, 1991), additional research is needed to identify species occurring off Alaska, due to latitudinal Methods differences in species composition. At present, little is known about the ecology of pe- Samples lagic juvenile rockfish off Alaska. Most species have not even been described at this stage of development (see The first batch of specimens (n = 23) to be examined Kendall, 1991), and it is presently difficult or impossible was collected by the International Pacific Halibut Com- to identify the larvae and juveniles of many species of mission (and supplied to Alaska Department of Fish rockfish from their morphology (Gray et al., 2006). and Game) on 25 and 27 September 2002 in Shelikof Consequently, it is not possible to trace their early lives, Bay, off the coast of Southeast Alaska (Fig. 1; Table 1). to investigate their ecology, or to use them for popula- The samples