Biological Report 82(11.107) TR EL-82-4August 1989

Species Profiles: Life Histories andEnvironmental Requirements of Coastal Fishes 3and Invertebrates (Pacific Southwest) ~O ~8

PACIFIC AND SPECKLED SANDDABSOtto 'r .r 7 .7

03 .06

069 01 4

Biological Report 82(11. 107)TR EL-82-4

August 1989

Species Profiles: Life Histories and Environmental Requirements of CoastalFishes and Invertebrates (Pacific Southwest)

PACIFIC AND SPECKLED SANDDABS

by

Joseph P. RackowskiDepartment of Fisheries and Wildlife

Oregon State UniversityHatfield Marine Science Center

Newport, OR 97365

and

Ellen K. PikitchUniversity of Washington

School of Fisheriesrisneries kesearcn institute

Seattle, WA 98195

Project Officer Ac,. . .

David Moran TU.S. Fish and Wildlife Service

National Wetlands Research Ceriter

1010 Gause BoulevardSlidell, LA 70458

Performed for

Coastal Ecology Group U "-.U.S. Army Corps of Engineers -Waterways Experiment Station , -,

Vicksburg, MS 39180

and

U.S. Department of the Interior /9-1 I"Fish and Wildlife ServiceResearch and Development

National Wetlands Research CenterWasnington. DC 20240

PREFACE

This species profile is one of a series on coastal aquatic organisms,principally fish, of sport, commercial, or ecological importance. The profilesare designed to provide coastal managers, engineers, and biologists with a briefcomprehensive sketch of the biological characteristics and environmentalrequirements of the species and to describe how populations of the species may beexpected to react to environmental changes caused by coastal development. Eachprofile has sections on taxonomy, life history, ecological role, environmentalrequirements, and economic importance, if applicable. A three-ring binder isused for this series so that new profiles can be added as they are prepared.This project is jointly planned and financed by the U.S. Army Corps of Engineersand the U.S. Fish and Wildlife Service.

Suggestions or questions regarding this report should be directed to one ofthe fnllowinq addrercss.

Information Transfer SpecialistNational Wetlands Research CenterU.S. Fish and Wildlife ServiceNASA-Slidell Computer Complex1010 Gause BoulevardSlidell, LA 70458

or

U.S. Army Engineer Waterways Experiment StationAttention: WESER-CPost Office Box 631Vicksburg, MS 39180

, i I , ,ii

CONVERSION FACTORS

Metric to U.S. Customary

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square meters (m- 107-,6 -,quxe fe(etsquare kilometers (krn') 0 33--61 Sc:j Ire n! ers

hecta'es (ha) 24 471 ~'e

liter-, () 0 216:42cjbc meters (m33 1c.octecubic meters (m 0 0501:8 1 r, acrelec~t

milligrams (mg) 0 00003527 ouncesgrams ( 0 0627 ounce sk-!ooramns (kg) 2 205 Pounrds,meiric tors (1) 2 205,0 pounlds-Tmet:c tons (!) 1 102 sno!, tons

k oca onies 'ycal 3 968B~n h'ia n1

U.S. Cus~tomnary to Metric

ones 254 i-. neIerCinch~es 2 54 cent inlett-rs

Aln~ins 1 823 etre ,- ii1 1' r"1 C)09 k toin.ters

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Page

PREFACE...................................................................1iiiCONVERSION FACTORS .............................................. ........... ivFIGURES.................................................................. vACKNOWLEDGMENTS ............................................................ vii

NOMENCLATURE AND TAXONOMY ................................................... 1MORPHOLOGY AND IDENTIFICATION AIDS........................................... 1

Pacific sanddab ........................................................... 1Speckled sanddab .......................................................... 2

GEOGRAPHIC RANGE...................... ...................................... 2Pacific sanddab ........................................................... 2Speckled sanddab .......................................................... 2

REASON FOR INCLUSION IN THE SERIES........................................... 2LIFE HISTORY ................................................................ 2

Reproduction .............................................................. 5Early Development.................. ....................................... 6

GROWTH CHARACTERISTICS ...................................................... 7MIGRATION AND MOVEMENT OF ADULTS............................................. 9ECOLOGICAL ROLF ............................................................. 9

Food anid Feeding .......................................................... 9Species Association .............................. ........................ 10

ENVIRONMENTAL REQUIREMENTS .................................................. 11Substrate................................................................. 11Temperature ................... ........................................... 11Vegetation................................................................ 11Salinity ............... .................................................. 11Dissolved Oxygen ......... ................................... ............. 12Contaminants.......................................................... 12

COMMERCIAL AND RECREATIONAL IMPORTANCE.................................... 12Commercial Fishery............ ........................................ 12Sport Fishery......................................................... 13

LITERATURE CITED........................................................ 15

0v

FIGURES

Number Page

I Pacific sanddab (Citharichthys sordidus) ............................ 1

2 Speckled sanddab (Citharichthys stigmaeus) .......................... 1

3 Geographic distribution of Pacific sanddab along theCalifornia coast .................................................... 3

4 Geographic distribution of speckled sanddab along theCalifornia coast .................................................... 4

5 Larval stages of Pacific sanddab .................................... 6

6 Larval stages of speckled sanddab ................................... 6

7 Length-weight relationship for Pacific sanddab ...................... 8

8 Length-weight relationship for speckled sanddab ..................... 9

9 Commercial landings of sanddabs from 1915-1986 ...................... 12

Vi

ACKNOWLEDGMENTS

We thank Susan Jurasz for preparing the illustrations of both species ofsanddabs and for helping us to prepare the maps and graphs; and Ms. JoyceUnderhill, California Department of Fish and Game, Long Beach, for providingunpublished commercial landings data. We also wish to thank Dr. William Pearcy,Oregon State University, Corvallis, Dr. David Stein, Oregon State University,Corvallis, and Mr. Larry Quirollo, California Department of Fish and Game,Eureka, for their critical review of an earlier draft of this profile. Ms.Theresa Ketchum assisted in typing the manuscript.

O vii

Figure 1. Pacific sanddab Figure 2. Speckled sanddab(Citharichthys sordidus), 36 cm (Citharichthys stigmaeus), 14 cm(redrawn from Arora 1951). (redrawn from Bane and Bane 1971).

PACIFIC AND SPECKLED SANDDABS

NOMENCLATURE AND TAXONOMY maxillary bone extends to the forwardpart of the lower eye. Pelvic fins

Scientific name ......... Citharichthys are asymmetrical; fin of the eyed sidesordidus Girard is attached directly to the ventralPreferred common name ......... Pacific ridge (Miller and Lea 1972- Hartsanddab (Figure 1) 1973).Other common names ...Mottled sanddab,soft flounderScientific name ......... Citharichthysstigmaeus Jordan and Gilbert Pacific SanddabPreferred common name ........ Speckledsanddab (Figure 2) As the species name sordidusOther common names ..... Catalina sand- suggests, body and fin coloration ondab the eyed side is dull brown or tan andClass .................... Osteichthyes irregularly mottled with yellow andOrder ............... Pleuronectiformes orange (Miller and Lea 1972; HartFamily ................ Paralichthyidae 1973). The ridge between the eyes is

concave; the lower eye is longer tha,1the snout. Pectoral fin reaches tothe middle of the eye when projectedforward (Miller and Lea 1972). Gill

MORPHOLOGY AND IDENTIFICATION AIDS rakers 15-16 on the lower section ofthe first anterior arch; dorsal rays86-102, originating just anterior to

In species of Citharichthys, the the eye; anal rays 67-81, caudalbody is compressed, highly rounded; scales ctenoid on eyed side,asymmetrical and colored only on the cycloid on blind side (Arora 1951:left side. The blind side is usually Eschmeyer et al. 1983). Lateral linewhite or cream. The asymmetrical head scales 61-70; vertebrae 39-40; lengthis deep and blunt; both eyes are on to 16 inches (40 cm); weight to 2the left side. Jaws are symmetrical pounds (Arora 1951; Roedel 1953;and heavy with a median knob. The Miller and Lea 1972; Hart 1973).

1

Maximum reported total length (TL) 403 Alaska, to Magdalena Bay, Bajamm (Arora 1951; Chamberlain 1979). California (Wilimovsky 1954; Hart

1973; Townsend 1935; Miller and Lea1972; Ford 1965); most abundant in

Speckled Sanddab nearshore waters along central andsouthern California (Figure 4).

Coloration is olive brown or tan Speckled sanddabs inhabit depthswith black speckling on the eyed side, extending from the intertidal zone toand white to crcam on blind side 366 m (Fitch and Lavenberg 1971; Hart(Miller and Lea 1972; Hart 1973). 1973; Townsend 1935; Ford 1965).Ridge between eyes flat to convex;pectoral fin, projected forward, fallsshort of the lower eye. Gill rakers8-10 on the lower section of the first REASON FOR INCLUSION IN THE SERIESanterior arch; dorsal rays 75-97,first 2 or 3 rays dnterior to uppereye (Batts 1964; Miller and Lea 1972). The Pacific sanddab isAnal rays 58-77, caudal rounded; commercially important in Californiascales imbricated, deciduous, ctenoio with demand often exceeding supply.on both sides of the body. Vertebrae Speckled sanddabs have little34-39 (generally 36); lateral line commercial importance because of theirstraight, scales 52-58. Length to small size. Throughout the late 1970'sabout 7 inches (17 cm); weight to and early 1980's sanddabs becameabout 1 pound (Miller and Lea 1972; increasingly important in theHart 1973; Wang 1981). Maximum commercial fishery, in both poundsreported length is 169 mm (Chamberlain landed and dollar value of the catch.1979).

Because sanddabs inhabit shallow,environmentally sensitive areas such

GEOGRAPHIC RANGE as bays and estuaries, it is importantto investigate the effects of

Pacific Sanddab pollutants and human interactions ontheir ecology.

Occurs along the Pacific coastfrom the Bering Sea to Cabo San

Lucas, at the tip of Baja California(Wilimovsky 1954; Miller and Lea LIFE HISTORY1972; Hart 1973; Roedel 1948; Arora1951). Most abundant along northcentral California, from Eureka to San In life history studies of theFrancisco, and fairly common in Citharichthys reviewed here, Arorasouthern California (Figure 3). (1951) provided the most completePacific sanddabs occupy depths to 306 review of the Pacific sanddab and Fordm, but are usually found at 18-275 m, (1965) investigated the generaland the optimum depth is 35-95 m biology, population dynamics, and(Hart 1973; Arora 1951; Roedel 1953; behavior of the speckled sanddab.Fitch and Lavenberg 1971; Miller and Reproduction of both species wasLea 1972). Pacific sanddabs tend to studied by Chamberlain (1979).inhabit shallower depths at higher Ahlstrom et al. (1984) publishedlatitudes (Chamberlain 1979). detailed information on the

development and distribution ofSpeckled Sanddab sanddab larvae. Feeding ecology of

the Pacific and speckled sanddabs wasThis species occurs along the described by Hulberg and Oliver (1978)

Pacific coast from Montague Island, and Ambrose (1976).

2

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.. . .. .. . .. .. ..

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34 -.- ~- -LOS ANGELES

PACIFIC OCEAN **A IG

32

122 1"8 116

Figure 4. Geographvic distribution of tne speckled sandcab alongo trieCalifornia coast.

Reproduction hours indicated that the fish spawned

in early morning (Ford 1965).

Reproductive patterns of the twospecies of Citharichthys are similar. Three distinct groups of egg

Differences in water temperature maturity staqes have been describedfrom year to ,..ar may influence the for the two species of sanddabstime of spawning (Chamberlain 1979; reviewed here: stage I, immature;Ford 1965). Southern species of stage II, small, semi-opaque to large

Citharichthys begin reproduction and granular; and stage III, mature.

earlier and continue it longer than Arora (1951) and Ford (1965) bothsanddabs in cooler northern waters concluded that multiple spawnings per

(Chamberlain 1979). Adults spawn near season occur because the three size

bottom in bays and the open ocean, groups of eggs are present

where water temperature is low. simultaneously in mature females.Vitellogenesis begins as early asFebruary for both species of Eggs of west coast species ofCitharichthys (Chamberlain 1979). Citharichthys are spherical,

translucent, similar in size, and

contain one oil globule at maturity.

Spawning season in Pacific Immature eggs may contain several oil

sanddabs, collected at depths of 35 to globules of various sizes. The modal

90 m from Point Reyes to San diameter of mature Pacific sanddabFrancisco, was determined from a eggs was reported to be about 0.650 mmseries of observations of egg size by Arora (1951). The average maximum(Arora 1951). The eggs were largest diameter of Pacific sanddab eggsfrom July to September; most reached collected off Orange County in August

fnax mum size in August. Male was 0.845 mm (Chamberlain 1979). Thedevelopment peaked during this same largest speckled sanddab eggs averagedperiod. By October nearly all females 0.448 mm in September, 0.540 mm in

were spent. Females matured at age 3, February, and 0.760 mm in May

at an average of 190 mm TL (Arora (Chamberlain 1979).1951).

Testes of mature Pacific andIn specimens of speckled sanddabs speckled sanddabs averaged 0.11% and

of 91 to 148 mm (TL), from depths of 5 0.21%-0.36% respectively of fresh, wet

to 45 m, collected on the intercanyon body weight (Chamberlain 1979). Weight

shelf off southern California, Ford of fresh, wet ovaries were 1.0% to(1965) found that spawning began in 4.4% of body weight for PacificApril, when more than 50% of all eggs sanddab and 1.7% to 5.6% for speckled

were mature, and ended in September. sanddab (Chamberlain 1979).

Spawning coincided with a suddendecline in bottom water temperature No fecundity estimates for

(from 15 to 10.5 'C) due to spring Pacific sanddabs have been published.upwelling (Ford 1965). No mature eggs Ford (1965) reported that speckled

were found in sanddabs collected in sanddabs 50.0 to 67.5 mm TL

October or December. Female speckled contained only immature eggs of 0.03

sanddabs matured at age 2. at an to 0.15 mm, and fish larger than 78 mm

average length of 70 to 80 mm ;L (Ford TL had large numbers of mature or

1965). Spawning male and female maturing eggs 0.35 to. 0.77 mm inspecklcd sanddabs congregated at the diameter. Estimated numbers of eggshead of La Jolla Canyon during spring spawned per season by speckled

and summer. The collection of large sanddahs were 4,200 at lenqths of 85-numbers of recently fertilized eggs of 90.5 mm, 12,100 at 109.5-110.5 mm. and

sanddabs in surface net tows over 22,500 at greater than 129.0 mm TL

the intercanyon shelf at 0800 to 0900 (Ford 1965). Many post-spawning males

5

and females of both species (whichwere sampled at various times duringthe spawning season) retained the hulk . iof the sperm or ovarian mass, suggest- 10ing that relatively smIal 1 numbers ofsperm and eggs are released throughoutthe spawning season, and multiplespawnings occur.

Early Development

Chamberlain (1979) published themost detailed description ofCitharichthys eggs and embryos, and 1 ."-AhIstrom et al. (1984), the best study Fof larval stages. .

Larvae hatch at about 2.0 mm TL 14 5

or less, and complete the yolk-sacstage of development at about 3.0 mmTL (Wang 1981). Paralichthidflatfish, including sanddabs, are Figure 5. Larval development of theusually sinistral; during Pacific sanddab (Ahlstrom and Mosermetamorphosis the larvae transforms to 1975).a juvenile form with both eyes on theleft side of the head and anasymmetrical pigmentation pattern(Ahlstrom et al. 1984). Timing ofmetamorphosis in flatfish is more -- -

closely related to environmental qh --7--- Itemperature and individual size thanto age (Ahlstrom an' Moser 1975). 6.6MM

Citharichthys larvae longer than 5 mmcan be identified on the basis of acombination of pigment characters,meristic counts, and location ofcapture (Ahlstrom et al. 1984;Ahlstrom and Moser 1975). m o

At about 5 mm TL, Pacific

sanddabs de\elop two elongated,ornamental rays at the insertion ofthe dorsal fin and two corresponding "rays from the pelvic fins (Figure 5).Speckled sanddabs develop no such raysduigteir developm ent. (Fgre6. UPacific sanddabs lose the rays during D'I ,4metamorphosis (Porter 1964). Themeristic characteristics of adults areuseful in identifying young Figure 6. Larval development of theCitharichthys (see summary of adult speckled sanddab (AhIstrom and Mosercharacteristics). 1975).

6

Larval Pacific sanddabs have cover from predators, and moregroupings of melanophores along the suitable temperature (Ahlstrom and

dorsal, anal, caudal, and eyed-side Moser 1975; Chamberlain 1979; Fordpectoral fins, whereas speckled 1965); in addition larvae are carriedsanddab larvae lack melanin long distances by ocean currents.(Chamberlain 1979; Porter 1964).Pacific sanddabs lose much of the Larvae of the four species ofmelanin during the late juvenile a-_ J Citharichthys composed 87% of allearly adult development stages, hut flatfish larvae sampled during thethis characteristic is useful in California Cooperative Oceanicdifferentiating the juveniles of the Fisheries Investigations (CALCOFI)two species. At about 28 mm standard between 1955 and 1960 (Ahlstrom andlength (SL) , myotomes take on a W- Moser 1975; Ahlstrom 1969). Eggs andshaped appearance. Pigmentation on larvae are planktonic, occurring alongthe eyed side of Pacific sanddabs the entire CALCOFI sampling area, andbecomes more pronounced durinq growth were collected in large numbers fromfrom 110 to 120 mm SL. June to August. Loeb et al. (1983)

reported that larval flatfishLocation of capture is important abundance peaked from October through

to the identification of sanddab November, primarily because largelarvae because of the differences in numbers of Pacific and speckledtheir distribution (Ahlstrom and Moser sanddabs were found in all nearshore1975). The geographic distributions regions.of larval speckled and PacifiLsanddabs overlap each other and alsothose of larval C. fragilis (gulfsanddab), and C. xanthostigma (longfin GROWTH CHARACTERISTICSsanddab) in the southern portion oftheir range (Baja to southernCalifornia). Location of capture may Growth in sanddabs has been shownoften help to differentiate gulf and to be regulated by numerous factors:longfin sanddabs gathered from trawls prey availability, population density,north of their range. environmental temperature, salinity,

and suitable habitat (ChamberlainPelagic speckled sanddab larvae 1979; Ford 1965; Ehrlich et al. 1979;

have been collected from close inshore Hulberg and Oliver 1978).to 320 km offshore (Berry and Perkins1966); and pelagic larvae of Pacific Most age and growth studiessanddabs from close inshore (Berry and conducted on Pacific and speckledPerkins 1966) to 724 km offshore sanddabs have been based on the scale(Ahlstrom 1965). Juvenile method of age determination. FemalesCitharichthys usually inhabit the of both species grow faster and attainentire bathymetric range of the larger sizes than males (Chamberlainspecies, and may prefer the same 1979: Ford 1965; Villadolid 1927). Insubstrate types as the adults the Pacific sanddab. the growth rate(Chamberlain 1979). Ahlstrom (1959) is faster and the life span (8-10reported sarddab larvae distributed years) is longer than in the speckledbetween the surface and 88 m in depth. sanddab (3-4 years) (Arora 1951: FordDuring spring, summer, and fall 1965).transformation and settling, speckledsanddabs of 25 to 75 mm TL were most Pacific sanddabs grow rapidlyabundant at depths of 15 to 25 m on from July to November (Arora 1951).the intercanyon shelf (Ford 1965). Average total lengths of PacificLarvae and juveniles move relatively sanddabs at ages I to IV (males andshort distances in search of prey, females combined) are 95, 148, 192,

7

and 226 mm. Corresponding average Arora's (1951) length-weight equationweights are 6.6, 27.8, 69.3, and 116.5 (logW = 5.59 + 3.26 logL) was similarg (Arora 1951). Throughout to Chamberlain's equation (Figure 7 ).development, weight increased at a The two equations have different Yrate slightly higher than the cube of intercept values, however, becausethe length (Arora 1951). After the Arora used total length measurementsfourth year, females grew faster than and Chamberlain measured standardmales; at the end of the seventh year, length. Both researchers determinedmales averaged 246 mm, and females, that standard length increases 84 mm274 mm TL (Arora 1951). Villadolid for every 100-mm increase in total(1927) reported similar growth rates length.for Pacific sanddabs collected off SanFrancisco and Monterey.

Ford (1965) examined 50 speckledArora (1951) determined the age sanddabs, 50-148 mm TL, to estimate

composition and length-weight relation length-at-age. Growth rates arefor Pacific sanddabs fron 150 fish typical of most fish; there is a verycollected near the Farallon Islands, rapid increase in length during theoff the northern California coast; and first year (Ford 1965). SeasonalChamberlain (1973) collected length variation in growth is similar to thatand weight data for this species in in Pacific sanddabs: most rapid growthtrawl surveys off southern California. is during summer and early fall. At

the end of the first year, speckledsanddabs attain 55%-60% of the mediantotal length and 13%-18% of the medianweight attained at the end of thethird year (Ford 1965). Total length

W-3 442 ." ranges (millimeters) for groups 0-Ill220 were 25-75, 76-105, 106-120, and 121-

rogW W .1 ft *27SSL / 150. Estimated mean total lengths at2 .0 the end of the first, second, and

third year were 66.5, 93.8, and 111.0,a mm for males and 69.0, 99.6, and

126.6 mm for females (Ford 1965).to Growth rate decreased at a median

total length of 70 mm. Differencesbetween the sexes in total length and

0 , median dry weight near the end of thethird year of life were about 16 mm

,00. and 1.9 g for speckled sanddabs (Ford1965).

Ford (1965) used total length40- measurements in relating dry and wet

weight to length in speckled sanddabs:Loglo Dry Wt(g)= -6.2753 + 3.2953

0 1 , , ,Log 10 TL; and Logj0 Wet Wt(g)= -5.575050 0 I 2 2' 300 3; + 3.2953 Loglo TL. These equations

SWt.dtd t-. , ,"Wi,-"Wor are similar to the length-weightrelation developed by Chamberlain

Figure 7. Length-weight relationship (1979)(Figure 8). Once again, thewith fitted curve for Pacific sanddab method of measurement is responsible(Chamberlain 1979). for the differences in coefficients.

8

by short-term, dipl variations inw.l.e -environmental conditions (cord IJG5).

55 LogW 5.71629+ 3.4

5539 Lg L

0- t.0.9576 The abundance of speckledsanddabs peaked in Ki,,g Harbor,

45- Redondo Beach, CA, from winter throughearly summer, when bottom temperatures

40 were low (Ehrlich et al. 1979). Aftersummer and fall breakdown of thermal

35 stratification, the numbers ofspeckled sanddabs decreased in King

a 30- and Los Angeles Harbors "hrlich etal. 1979: Stephens et al. 1973).

25/

Water temperature fluctuations,20 pollution, and human interference

15 increase stress on inner harborsanddab populations by causing

increased rates of infection,/ parasitism, and higher mortality

5- (Ehrlich et al. 1979; Stephens et al.1973). Due to the instability of

61 0 i - inner harbor environments which may30 60 90 120,so ISO force fish to move seaward into other

Sanda d L.wth-mfII'.,r waters, the occurrence ofsubpopulations of sanddabs in inner

Figure 8. Length-weight relationship harbor waters is unlikely (Ehrlich et

with fitted curve for speckled sanddab al. 1979; Chamberlain 1979; Stephens

(Chamberlain 1979). et al. 1973 ; Taylor 1957).

ECOLOGICAL ROLE

MIGRATION AND MOVEMENT OF ADULTSFood and Feeding

Adult Citharichthys are not Larval Citharichthys have beenhighly migratory (Chamberlain 1979). described as planktonic by severalMovement of adult sanddabs is authors (AhIstrom and Moser 1975;influenced by prey availability Fitch and Lavenberg 1971). Postlarvae(Hulberg and Oliver 1978; Cailliet et eat zooplankton and adults eat a wideal. 1978), seasonal temperature variety of small pelagic fish,fluctuations (Ehrlich et al. 1979; cephalopods. crustaceans, and marineStephens et al. 1973; Ford 1965), and worms (Hogue and Carey 1982; Hulbergsubstrate type (Feder et al. 1974: and Oliver 1978; Ambrose 1976; FitchAmbrose 1976). and Lavenberg 1971; Ford 1965).

Population densities and age Marine fish larvae feed on manycomposition of speckled sanddabs on kinds ot organisms buL copepod naupliithe intercanyon shelf, off La Jolla. appear to predominate in their dietsCA. were relatively stable, reflecting (Houde and Taniguchi 1979). Larvalthe constancy of the bathymetric survival and growth iate and thedistribution and abundance over a length of the larval period depend onsampling period averaging 30 days. concentrations of food organisms, butDistribution was not greatly affected during the larval period marine fish

9

are also most vulnerable to predation amphipods, cumaceans and mysids;(Houde and %rhekter 1980). adults (76 mm and larger) relied less

on these forms and seemed toMorphological adaptations such as concentrate on the larger decapods,

long symmetrical jaws, sharp teet!, ,olluzkz, -oid smail fish (Ford 1965).and long serrated gill rakers allow Speckled sanddab prey consistedsanddabs to grasp and hold animals primarily of crustaceans (61%); thewhile swimming in midwater (Pearcy and major taxa, in order of importance,Hancock 1978; Alexander 1974). were Amphipoda, Decapoda, Mysidacea,Significantly greater stomach fullness Cumacea, Copepoda, and Isopoda (Fordin Pacific sanddabs collected at dawn 1965). In concurrence, Ambrose (1976)in trawl samples (versus samples found amphipod and mysid crustaceanscollected from trawls at other times) to be the most important prey forsuggests that the fish are nocturnal speckled sanddabs at seaward stationsfeeders (Hopkins and Hancock 1980). of Elkhorn Slough, CA. When speckled

sanddabs fed at inner slough stationsYoung and Mearns (1980), in work they ate polychaetes, bivalve siphons,

on the flow of pollutants through the decapods, and (to a lesser extent)marine food web, assigned sanddabs to fish.primary and secondary carnivore Speckled sanddabs had the secondtrophic positions. Hulberg and Oliver highest mean trophic diversity among(1978) showed that euphausid and mysid all species sampled (0.51, on a scalecrustaceans accounted for most of the of 0-1), at stations where it occurrednumber and volume of crustaceans eaten (Ambrose 1976). Speckled sanddabs wereby adult Pacific sanddabs of 85 to generalized feeders at seaward of211 mm SL. The polychaetes eaten by Elkhorn Slough, and much moresanddabs were almost exclusively specialized feeders at inner sloughspecies that feed at the sediment stations where they fed on one speciessurface (e.g., Nothria elegans, of mysid, Acanthomysis davisiiAmaeana occidentalis, and Magelona (Cailliet 1977; Ambrose 1976).sacculata). Tentacles of A. Speckled sanddabs rely on sight foroccidentalis were eaten more feeding and pick food cleanly from thefrequently than the entire animal, bottom, without much extraneousJuvenile rockfishes (Sebastes spp.) material (Ford 1965). These fish takeand razor clams (Siliqua spp.) were advantage of normally unavailablealso found in stomachs of Pacific infauna dislodged from sand by thesanddabs. Habits of the prey suggest digging rays Urolophus halleri andPacific sanddabs are opportunistic Myliobatis californica. Since speckledfeeders and poor diggers (Hulberg and sanddabs reach densities of up to 1/ 2

Oliver 1978). over sand, they may increase themortality rates of infaunal prey

Cross et al. (1985) reported that disturbed by digging rays (VanBiaricomthe proportion of crustaceans 1982). Poor visibility and substratedecreased and the proportion of type at some inner slough stations maypolychaetes increased in the Pacific have affected speckled sanddab feedingsanddab diet, along an increasing habits (Ambrose 1976). Food types atpollution gradient of municipal inner slough areas did not appear to bewastewater on the mainland shelf near a limiting factor (Ambrose 1976).Los Angeles, CA. In the same study,

speckled sanddabs fed primarily onbenthic, epibenthic, and nektonic Species Associationcrustaceans.

In southern California, PacificJuvenile speckled sanddabs, sanddabs are found in associations

shorter than 75 mm, fed on copepods, with Dover sole, Microstomus

10

pacificus, pla"nfin midshipman, sanddabs tolerated sediments having aPorichthys notatus, pink seaperch, wide range of grain sizes and thatZalembius rosaceus, and shortspine grain size had no effect on thecombfish, Zaniolepis frenata quantity of suitable food organisms(Chamberlain 1979; Stephens et al. available to speckled sanddabs.1973). Ambrose (1976) reported substrate and

turbidity to be the most likelyLarval Pacific sanddabs are factors limiting the movement of

preyed on by albacore (Thunnus speckled sanddabs in Elkhorn Slough.alalunga), salmon (Oncorhynchus spp.),chub mackerel (Scomber japonicus), and Temperatureinvertebrates such as medusae andctenophores (Fitch and Lavenberg Ehrlich et al. (1979) estimated1971) a temperature range of 8-13 °C for

efficient growth, in a laboratorystudy of speckled sanddabs from King

In southern California, speckled Harbor. Although only limitedsanddabs are found in associations in information is available on theshallow water with California tongue- affects of temperature on sanddabfish, Symphurus atricauda; hornyhead ohysiology , it is generally expectedturbot, Pleuronichthys verticalis; and that temperature affects oocyteEnglish sole, Parophrys vetulus maturation, time of spawning, larval(Chamberlain 1979; Stephens et al. development, adult and larval movement1973; Ford 1965). into different habitats, food

availability, and growth rate.Juveniles and adult, of both

species are preyed on by larger fish Densities of juvenile and adultsuch as the California halibut, speckled sanddabs were higher atParalichthys californicus (Ford 1965). depths greater than 15 m, where

temperatures were lower and relativelystable, than at depths less than 15 m.Speckled sanddabs seemed to favor a

ENVIRONMENTAL REQUIREMENTS temperature range of 10.0 to 20.5 'C,over a depth range extending to 45 m(Ford 1965).

Substrate

Both species of sanddabs reviewed Vegetationhere have similar preferences forsandy bottom areas along the Information concerning theCalifornia coast (Hulberg and Oliver specific vegetation requirements for1978; Hart 1973; Ambrose 1976; sanddabs was not found in theCailliet et al. 1978; Ford 1965). literature. Larvae, postlarvae, andChamberlain (1979) collected sanddab young juvenile sanddabs may increasespecimens from fine sand and sandy- survival by inhabiting vegetated areasmud containing broken shell material, where protection from predators isFeder et al. (1974) reported Pacific available and prey organisms are moresanddabs to be dominant in deep sand highly concentrated as compared withor sandy-mud areas. Speckled sanddabs open areas.prefer irreoularities and foreignobjects in their habitat, resulting intheir higher densities around rock Salinitypilings, pier pilings, and canyons(Feder et al. 1974; Ford 1965). Ford Chamberlain (1979) estimated the

(1965) determined that speckled specific gravity of fresh eggs of

0 I11I I

speckled sanddabs to he demersal at COMMERCIAL AND RECREATIONAL IMPORTANCE1.025. As the salinity increases to1.045, sanddab eggs become planktonic.Eggs of both species hatch in salt Commercial Fisherywater. Salinity requirements forjuveniles and adults oere not found in The two species of Citharichthysthe literature. discussed here are taken incidentally

with other bottom fish in commercialDisselved Oxygen fisheries (Frey 1971). The Pacific

sanddab ranked second in abundanceExplicit physiological require- among fish species collected in trawl

ments for dissolved oxygen were not surveys conducted from 1969-1972 byfound in the literature, the Southern California Coastal Water

Research Project (1973). During trawlContaminants surveys conducted on Santa Monica Bay

over a 6 year period, Carlisle (1969)Livers of Pacific sanddabs found speckled sanddabs to be the most

collected near sewage outfalls had abundant species sampled.higher levels of DDTs, PCBs, PCBmetabolites, copper, and zinc than did Because of their small size,a control site. Concentrations of DOT speckled sanddabs are usuallymetabolites and cadmium were sometimes discarded at sea or ground up for usehigher at the control site, but that in fish meal. In the Los Angelessite may be exposed to some area, speckled sanddabs obtained fromcontamination. Gonads of Pacific a commercial hook-and-line fishery,sanddabs had higher concentrations of were sold in local markets until theDDT, PCBs, and zinc near the sewage late 1940's (Anon. 1949).outfalls relative to the control site;there was not a similar trend for Most Pacific sanddabs arecopper and cadmium (Brown et al. 1986). harvested commercially by bottom

3 00

too

300

080

03

me low 1413 Ila low0 .80 two0 is" .0w M45 '9D 49 60

Figuro 9. Commercial landings of sanddabs, 1915 - 1986 (Frey 1971: Joyce

Underhill. California Department of Fish and Game, Long Beach, CA: pers. comm.).

12

fishermen using otter trawls (Fitch indicated that commercial fishand Lavenberg 1971). The commercial buyers were paying $0.37 per poundPacific sanddab catch is landed almost for Pacific sanddabs.entirely from the ports of Eureka, SanFrancisco, and Monterey (Fitch and Sport FisheryLavenberg 1971; Anon. 1949). Before1938, San Francisco landings amounted Sanddabs are caught by sportto more than 95% of the total fishermen with hook-and-line. Wire incommercial catch. Highest landings to the form of a hoop, around whichdate were in 1917 when more than 2 several hooks are fastened, is baitedmillion pounds were taken (Anon. with squid, fish, shrimp, or clams and1949). Landings then declined lowered to a point close to the bottom(Figure 9), rose to 2 million pounds (Fitch and Lavenberg 1971). Sandyin 1925, and averaged about 500,000 bottom areas with consistently goodpounds from 1930-1970 (Arora 1951, fishing include the horseshoe kelpAnon. 1949). Commercial landings from area west of Los Angeles Harbor and1970-1986, averaged over 900,000 areas offshore from La Jolla, Newportpounds (Figure 9), indicating an Beach, Avalon, San Pedro, Malibu,increased demand for this species Goleta, Pismo Beach, Pacific Grove,(Joyce Underhill, California Moss Landing. and CapitolaDepartment of Fish and Game, Long .Chamberlain 1979; Fitch and LavenbergBeach, CA; pers. comm.). Price 1971). Fitch and Lavenberg (1975)quotations from the Fisherman's noted that speckled sanddabs makeMarketing Association in April 1987, interesting additions to aquaria.

* 13

LITERATURE CITED

Ahlstrom, E.H. 1959. Vertical Ambrose, D.A. 1976. Thedistribution of pelagic fish eggs distribution, abundance, and feedingand larvae off California and Baja ecology of four species of flatfishCalifornia. U.S. Fish Wiidl. Serv. in the vicinity of ElkhornFish. Bull. 60:107-146. Slough, California. M.S. Thesis,

San Jose State University. 121 pp.

Ahlstrom, E.H. 1965. Kinds and Anonymous. 1949. The commercialabundances of fishes in the fish catch of California for theCalifornia current region based on year 1947 with a historical reviewegg and larval surveys. Calif. 1916-1947. Calif. Dep. Fish Game.Coop. Oceanic Fish. Invest. Rep. Fish. Bull. No. 80. 87 pp.10:31-52.

Arora, H.L. 1951. An investigationAhlstrom, E.H. 1969. Mesopelagic and of the California sand dab,

bathypelagic fishes in the Citharichthys sordidus (Girard).California current region. Calif. Calif. Fish Game 37:3-42.Coop. Oceanic Fish. Invest. Rep.13:39-44. Bane, G.W., and A.W. Bane. 1971.

Pages 124-126 in Bav fisheb ofNorthern California. Mariscos

Ahlstrom, E.H., and H.G. Moser. Pub-ications, Southanpton and lew

1975. Distributional atlAs cf fish York.larvae in the ualifornia Currentregion: flatfishes, 1955 through Batts, B.S. 1964. Lepidology of1960. Calif. Coop. Oceanic Fish. adult pleuronectiform fishes ofInvest. Rep. Atlas No. 23. 207 pp. Puget Sound, Washington. Copeia

1964 (4):666-673.Ahlstrom. E.H., K. Amaoka, D.A.

Hensley, H.G. Moser, and B.Y.Sumida. 1984. Pleuronectiformes: Berry, F.H., and H.C. Perkins. 1966.Development. Pages 640-670 in H.G. Survey of pelagic fishes of theMoser, W.J. Richards, 0.M. Cohen. M. California current area. U.S. FishP. Fahay, A.W. Kendall, Jr., and S. Wild. Serv. Fish. Bull. 65:625-682.L. Richardson, eds. Ontogeny andsystematics of fishes. AmericanAssociation of Ichthyologists and Brown, D.A., R.W. Gossett, G.P.Herpetologists Special Publication Hershelman, C.F. Ward, A.M. Westcott,1. 760 pp. and J.N. Cross. 1986. Municipal

wastewater contamination in SouthernCalifornia, U.S.A., Bight. Part I.

Alexander, R.M. 1974. Functional Metal and organic contaminants indesign in fishes. The Anchor Press, sediments and organisms. Mar.Tiptree Essex. 160 pp. Environ. Res. 18:291-310.

15

Cailliet, G. M. 1977. Several to the Pacific coast fishes ofapproaches to the feeding ecology of North America from the Gulf offishes. Pages 1-i3 in C.A. Alaska to Baja California.Simenstad and S.J. Lipovsky, eds. Houghton Mifflin Co., Boston. 336Gutshop '76 fish food habits pp.studies. Proc. First Pac.Northwest Tech. Workshop, October13-15, 1976. University of Feder, H.M., C.H. Turner. and C.Washington Press, Seattle. Limbaugh. 1974. Observations on

fishes associated with kelp bedsin Southern California. Calif.

Cailliet, G., B.S. Antrim, and D.S. Dep. Fish Game, Fish Bull. 160. 144Ambrose. 1978. Trophic spectrum pp.analysis of fishes in Elkhorn Sloughand nearby waters. Pages 118-128 Fitch, J.E., and R.J. Lavenberg.in C.A. Simenstad and S.J. Lipovsky. 1971. Pages 41-43 n Marine foodeds. Gutshop '78 fish food habits and game fishes of California.studies. Proc. Second Pac. University of California Press,Northwest Tech. Workshop, October Berkeley.10-13, 1978, University ofWashington Press, Seattle. Fitch, J.E.. and R.J. Lavenberg.

1975. Pages 32-34 in Tidepool andCarlisle, J.G.. Jr. 1969. Results of nearshore fishes of California.a six year trawl study in an area of University of California Press,

heavy waste discharge: Santa Monica Berkeley.Bay, California. Calif. Fish Game55:26-46. Ford, R.R. 1965. Distribution,

population dynamics and behavior ofChamberlain, D.W. 1979. Histology of a bothid flatfish, Citharichthys

the reproductive systems and stigmaeus. Ph.D. Dissertation.comparison of selected morphological University of California, San Diego.characters in four Eastern Pacific 243 pp.species of Citharichthys (Pisces:Bothidae). Ph.D. Dissertation. Frey, H.W. (ed). 1971. CaliforniaUniversity of Southern California, living marine resources ana theirLos Angeles, CA. 297 pp. utilization. California Department

of Fish and Game. 148 pp.Cross, N.J., J. Roney, and G.S.

Kleppel. 1985. Fish food habits Hart, J.L. 1973. Pages 596-599 inalong a pollution gradient. Calif. Pacific fishes of Canada. Fish.Fish Game 71:28-39. Res. Board Canada. Bull. 180.

Ehrlich, K.F., J.S. Stephens, G.Muszynski, and J.M. Hood. 1979. Hopkins, J.A., and M.K. Hancock.Thermal behavior of the speckled 1980. Diel feeding pattern andsanddab, Citharichthys stigmaeus: prey of the Pacific sanddab,laboratory and field investigations. Citharichthys sordidus. Am. Zool.

U.S. Natl. Mar. Fish. Serv. Fish. 20(4):950.

Bull. 76(4):867-872.Hogue, E.W., and A.G. Carey, Jr.

Eschmeyer, W.N., E.S. Herald, and H. 198?. Feeding ecology of 0-ageHammann. 1983. Lefteye Flounders: flatfishes at a nursery ground onFamily Bothidae. Pages 283-286 in the Oregon coast. U.S. Natl. Mar.R.G. Peterson, ed. The Petersun Fish Serv. Fish. Bull. 80(3):field guide series: a field guide 555-565.

16

Houde, E.D., and R.C. Schekter. 1980. Porter, P.E. 1964. Notes onFeeding by marine fish larvae: fecundity, spawning and early lifedevelopment and functional history of Petrale sole (Eopsettaresponses. Environ. Biol. Fishes jordani). with descriptions of5:315-334. flatfish larvae collected in the

Pacific Ocean off Humboldt Bay,Houde, E.D., and A.K. Taniguchi. California. M.S. Thesis. Humboldt

1979. Laboratory culture of marine State College. 124 pp.fish larvae and their role in marineenvironmental research. Pages Roedel, P.M. 1948. Common marine176-205 in F.S. Jacoff, ed. fishes of California. Calif. Fish

Advances in marine environmental Game Bull. No. 68. 150 pp.research. Proc. of a symp.,Environ. Res. Lab., U.S. Roedel, P.M. 1953. Common oceanEnvironmental Protection Agency, fishes of the California Coast.Narrangansett, R.I. Rep. No. EPA- Calif. Fish Game Bull. No. 91. 184600/9-79-035. pp.

Southern California Coastal WaterHulberg, L.W., and J.S. Oliver. Research Project. 1973. The

1978. Prey availability and the ecology of the Southerndiets of two co-occurring flatfish. California Bight: implications forPages 29-36 in C.A. Simenstad and water quality management. Three-S.J. Lipovsky, eds. Gutshop '78 year report of the SCCWRP. 531 pp.fish food habits studies. Proc.Second Pac. Northwest Tech. Stephens, J.S., Jr., D. Gardiner, andWorkshop, October 10-13, 1978. C. Terry. 1973. The demersalUniversity of Washington Press, fish populations of San PedroSeattle. Bay. Pages 147-166 in D.F. Soule

and M. Oguri, eds. Marine Studiesof San Pedro Bay, California. Part

Loeb, V.J., P.E. Smith, and H.G. II, Biological Investigations.Moser. 1983. Geographical and Allan Hancock Foundation andseasonal patterns of larval fish University of Southern Calif.,species structure in the California Los Angeles.current area, 1975. Calif. Coop.Oceanic Fish. Invest. Rep. 24: Taylor, F.H.C. 1957. Variations and132-151. populations of four species of

Pacific Coast flatfish. Ph.D.Dissertation. University of

Miller, D.J., and R.N. Lea. 1972. California, Los Angeles. 351 pp.Guide to the coastal marine fishesof California. Calif. Dep. Fish Townsend, L.D. 1935. Notes onGame. Fish Bull. 157. 235 pp. Citharichthys sordidus and C.

stigmaeus with an extension ofPearcy, W.G., and D. Hancock. 1978. range. Copeia 1935 (4):113.Feeding habits of Dover sole,Microstomus pacificus; rex sole, VanBlaricom, G.R. 1982. Experimental

Glyptocephalus zachirus; slender analyses of structural regulation in

sole, Lyopsetta exilis; and Pacific a marine sand community exposed to

sanddab, Citharichthys sordidus, in oceanic swell. Ecol. Monogr. 52:283-

a region of diverse sediments and 306.bathymetry off Oregon. U.S. Natl.Mar. Fish. Serv. Fish. Bull. Villadolid, D.V. 1927. The76(3):641-651. flatfishes (Heterosomata) of the

,mm17

Pacific Coast of the United States. Wilimovsky, N.J. 1954. List of thePh.D. Dissertation. Stanford fishes of Alaska. StanfordUniversity, 332 pp. Ichthyol. Bull. 4:279-294.

Young, D.R., and A.J. Mearns. 1980.Wang, Johnson C.S. 1981. Taxonomy of Pollutant flow through the marinethe early life stages of fishes -- food web; progress report to thefishes of the Sacramento-San Joaquin Chemical Threats to Man and theEstuary and Moss Landing Harbor - Environment Program, NationalElkhorn Slough, California. Science Foundation, Washington, Dr.Ecological Analysts, Inc., Concord, Nat. Tech. Info. Serv., PB82-CA. 168 pp. 158502, Springfield, VA. 131 pp.

18

30272 -?i _______________

REPORT DOCUMENTATION 3.ACPOWTO N 2. 36 XOCWWWS APwso noPAGE 113iological__Report 82(1_1.107) 'l__________

4. ite ndSutiioSpecies Profiles: Life Histories and Environmental I lae aRequirements of Coastal Fishes and Invertebrates (Pacific Southwest) 4.August 1989Pacific and Speckled Sanddabs 4

Joseph P. Rackowski1 and Ellen K. Pikitch2 .lweOu~a e

1 Prte"'ing organization N~ame and Addie,3. 20 PWeoafs/tolmsW " m.~Department of Fisheries and Wildlife 2Fisheries Research InstituteOregon State University School of Fisheries is nitic~ao ruc.Gnwwa N

Hatfield Marine Science Center University of Washington cNewport, Oregon, 97365 Seattle, WA 98195(G

12. Soangoring Organization Namei and Address

National Wetlands Research Center U.S. Army Corps of Engineers 13' Typ ONRoom tPw'aC"u

Fish and Wildlife Service Waterways Experiment StationU.S. Department of the Interior P.O. Box 63114Washington, D.C. 20240 Vicksburg, MS 391801.

is. supplementary Notes

*U.S. Army Corps of Engineers Report No. TR EL-82-4

Ill Abstract (umit 200 word s)ZY

I.Species profiles are literature summaries of taxo omy. liorpf ology, range, growthcharacter; ,ics, ecology, life history, and commercial importande of coastal species.Pacific sanddab, Citharichthys sordidus, and speckled anddab, itharichthys stigmeus,are common a lung the California coast from the intert dal zone/to dep t hs of 306 m.Pacific sanddabs spawn from July to September and sp ckled sa fdabs, from April toSeptember. Eggs and larvae are common throughout th range o the species. Averagelife span is 8-10 years in Pacific sanddabs and 3-4 ear s in peckled sanddabs. Femalesof both species live longer than males. Female Pacific sandd bs attain sexual maturityat age 3 and female speckled sanddabs, at age 2. P stlarvae eed on zooplankton; adultseat a variety of crustaceans and fish. Both specileprefer s ndy bottoms. The speckledsanddab was the most abundant species caught in t r surve ffsouthern California.Commercial catch statistics lump both species under anddab ".Average annual landings,1930-70, were 500,000 pounds and from 1971-86, landings rose to 900,000 poundsCommercial fish buyers paid $0.37 per pound for sanddabs in April, 1987.(AJow

17. omcmert Analysis a. Descriptors

Fishes Life cyclesFlatfishes SalinityFeeding habits TemperatureGrowth

b. Identlflrs/Ogen-Ended Terms

Pacific sanddab Speckled sanddabCitharichthys sordidus Citharichthys stigmaeusLife history spawning -Commercial and recreational importanceEcology Habi tat requirements

c. COSATI Field/Groug;

1I& Avaliability statemeant 19. Securfty Class (This ROD"i) 21. 11111,t e um

Unclassified 18Unlimited distribution 2MScrt Cls ffhis XL et l,

Unclassified(See ANSI-Z39.1 1) @~OA ~