Scorpaeniformes III

(Greenlings, sculpins, and relatives)

Class Actinopterygii

Order Scorpaeniformes

Number of families 10

Evolution and systematics

The Scorpaeniformes, the mail-cheeked fishes, are united by the presence of a bony ridge called a "suborbital stay" on the cheek, running horizontally below the eye and providing an armored look to the head of most species. The suborbital stay is a posterior extension of the second infraorbital (eye socket) bone. In the sculpins (Cottoidei), this suborbital stay tends to be very prominent, while in the greenlings (Hexagrammoidei) it is not easily seen.

The ancestral scorpaeniform stock is considered to have derived from a generalized percoid (perch) fish. That is to say, cottoid (sculpin) and hexagrammoid (greenling) fishes are among the most recently evolved, advanced fishes. The Scorpaeniformes is the fourth largest order of fishes, including about 29 families, about 260 genera, and 1,400 species. Most of these fishes are bottom-dwelling or live near the seabed. Nine families are covered in this chapter, with the remainder covered in Scorpaeniformes I and II.

Among the scorpaeniform fishes, the suborder Cottoidei includes between seven and 13 families in modern classifications. Historically, various additional cottoid families have been distinguished, often containing only one species. The most prominent families include the sculpins (Cottidae, with 305 species in 70 genera), fathead sculpins (Psychrolutidae, with 11 species, five genera), poachers (Agonidae, with 49 species, 20 genera), lumpfishes (Cyclopteridae, with 27 species, eight genera), and snailfishes (Liparididae, with 195 species, 13 genera). Also within the Cottoidei are two families of Lake Baikal fishes, the Cottocomephoridae (Baikal sculpins, with 24 species, eight genera), and Comephoridae (Baikal oilfishes, with two species, one genus). The Baikal oilfishes are distinguished by being the only viviparous (livebearing) cottoid fishes. A monotypic (one species) family, the Normanichthyidae, consists of one marine species off Chile that is often included within the Cottoidei. That species, Normanichthys crockery, would be the only cottoid fish having a swim bladder, but the anatomical description by Yabe and Uyeno (1996) concludes that the family is of uncertain systematic position within the Scorpaeniformes, and not correctly within the Cottoidei. Other families common in various classifications include the Cottunculidae (here included within the Psychrolutidae), the Icelidae (sometimes distinguished from Ereuniidae, both within the Cottidae here), and the Hemitripteridae (here included within the Cottidae). The species in the Psychrolutidae are usually included within the Cottidae in older works, but Jackson and Nelson (1998) have described the unique features of sensory canals and associated bones on the head which, together with other characters, distinguish the fathead sculpins from the other sculpin species. Some classifications place the liparidid fishes within the Cyclopteridae. Cottoid fishes probably first appeared in the North Pacific and only invaded the Arctic and North Atlantic Oceans 3.5 million years ago.

The zoogeography of cottoid fishes centers on the Pacific coast of North America. The other scorpaeniform suborder considered within this chapter is the Hexagrammoidei, the greenlings, which includes the largest family of fishes endemic to the North Pacific, the Hexagrammidae (11 species, five genera). Some classifications separate the combfishes into a separate family, the Zaniolepidae. Another family usually included within the Hexagrammoidei is the Anoplopomatidae, which includes the sablefish (Anoplopoma fimbria) and the skilfish (Erilepis zonifer). Sometimes the skilfish is separated into the monotypic family Erilepidae, also with these two families separated from other hexagrammoids into the Anoplopomatoidei.

Physical characteristics

The hexagrammoid fishes are perhaps the most generalized scorpaeniform fishes, resembling many perciform fishes. Hexagrammoid fishes have no head spines, and they include some of the only pelagic species, fish which have a fusiform body shape adapted to swimming in open water. Fishes of the genus Hexagrammos have multiple lateral lines, although Wonsettler and Webb (1997) have demonstrated that only the central trunk canal is innervated, as in other teleost fishes, so the biological significance of the other four, non-functional lateral lines, has become a mystery. As with the more diverse cottoids, most hexagrammids are adapted to dwelling on the sea bottom. They have no swim bladder and the pectoral fins are enlarged, with the lower edge attached further forward than the top edge, so that the fish can rest on these fins like a pair of elbows.

In the Cottoidei, extreme divergence of structure and function have yielded some of the most unusual-looking of all fishes. All cottoids lack the swim bladder and most have a flattened head, as well as enlarged pectoral fins like the greenlings. There are many skin adaptations, including loss of scales or modification of scales into bony plates. The Psychrolutidae (fathead sculpins) have flaccid bodies (puffy skin) with reduced skeletal structure. The Agonidae (poachers) have armor plates over their body, have all fin rays unbranched, and have lost the suborbital stay. The Cyclopteridae (lumpfishes or lumpsuckers) have a globular body covered with tubercles and with the pelvic fins modified into a sucking disc. The Liparididae (snailfishes) also have a pelvic sucking disc, but the body is without scales and is elongate. The Cottidae (sculpins) include the greatest divergence in body form and size, which is perhaps why various families historically have been separated from this taxonomic grouping. All cottid fishes have a single pelvic fin spine (except one species lacking pelvic fins) and no anal fin spine; they usually have naked skin, sometimes with cirri, sometimes with scales, and sometimes with prickles. Cottids lack swim bladders and tend to have large, flattened heads, often with pronounced spines and often with large eyes.

Color and fin shape lend toward a camouflaged appearance in most of these fishes. Cottoid and hexagrammoid fishes often display sexual dimorphism in color, body size, fin shape, or other features. Many cottid species have prominent male copulatory organs.

Distribution

The Cottoidei and Hexagrammoidei center their distribution in the eastern North Pacific Ocean, but antitropical (both hemispheres) distributions occur for cottoids in some instances. The Psychrolutidae include North Pacific and North Atlantic species, plus several species off New Zealand, Australia, and South Africa. Cottids similarly occur in the Northern Hemisphere (but in both marine and fresh waters) and off New Zealand, eastern Australia, and Argentina. Liparidids occur in both warm and cold marine waters of all the world's oceans, although rarely in the Indian Ocean. The Cyclopteridae occur only in cold, marine waters of the Northern Hemisphere. Agonids are found in the North Pacific, North Atlantic, and off southern South America.

The unique families of Lake Baikal cottoid fishes have been mentioned. Molecular genetic studies of Baikal cottoids (Kirilchik and Slobodyanyuk, 1997) reveal close relatedness with freshwater cottids such as Cottus bairdii from Lake Michigan and Cottus cognatus from Lake Michigan and Siberia. The genus Cottus is very widely distributed across North America and Eurasia, and the different species are all a very generalized cottid body type. The Baikal cottoids, although closely related to other freshwater cottids, have radiated into 22 endemic Baikal species (another four cottocomephorid species also occurring in other drainages of Siberia).

Habitat

The microdistribution of any species relates to habitat preference. The Northeast Pacific distribution of most cottoid species is reflected in an analysis of fish community structure of rocky shorelines of the North Pacific, which is dominated by cottids. The rocky intertidal of the Pacific coast of North America is dominated by various species of Artedius, Clinocottus, and Oligocottus. Other cottid genera have very narrow depth preferences in shallow subtidal marine waters. For example, the longfin sculpin, Jordania zonope, was considered extremely rare prior to the advent of scuba diving, because it inhabits vertical rock surfaces that are not amenable to sampling with nets. Similarly, the manacled sculpin, Synchirus gilli, was considered very rare until divers discovered it on the feather boa kelp, Egregia menziesi, on outer Pacific coast shores. The feather boa kelp does not occur, however, in protected inland seas like the Strait of Georgia (British Columbia), where the manacled sculpin spawns in the holdfasts of another kelp species, Alaria marginata. For the majority of cottoid species, very little is known of precise habits and habitat preferences.

The diverse snailfishes (Liparididae) occur broadly in the world ocean over a very wide depth range from the intertidal zone to greater than 23,000 ft (7,010 m) depth. Again, very little precise habitat information is available for the vast majority of species. Since most snailfishes possess a pelvic sucking disc, however, it is presumed that smooth surfaces of plants, animals, or rocks provide substrate for many of these species. As with other cottoid fishes, different species may prefer shores exposed to waves and tidal currents versus protected shores.

The Lake Baikal sculpins have been investigated since the eighteenth century. The diversification of these species seems in great part related to different depth preferences. Lake Baikal, at 5,315 ft (1,620 m) depth, is the deepest lake in the world.

The reason why the less diverse freshwater cottoid fishes have been studied more intensely than the vast diversity of marine species is that freshwater habitats are more accessible. Perhaps the most accessible marine habitat is the tidepool, and intertidal cottoids have received disproportionate study, except in comparison with fish species of commercial importance. A problem with the study and interpretation of tidepool fishes, however, has to do with the human perspective. Since people can most readily work around tidepools during low tides and calm weather, our interpretation of tidepools tends to focus on ecological advantages of the tidepool during a low tide (in calm weather) rather than during high tides and storms. Thus, tidepools are considered to offer refuge from subtidal predators during low tides, rather than to offer refuge from turbulence during high tides. Habitat can have widely divergent values and characteristics under different conditions, so the interpretation of habitat preferences needs to be tempered by perspective.

Discussions of fish habitat implicitly consider only adults in most studies. Tidepool studies reveal, however, that early juvenile stages of cottid species can have different habitat requirements than adults. Larval stages occupy the planktonic realm, a completely different habitat than that of most adult cottoids. Larvae of rocky intertidal cottids of various species have been shown to avoid drifting with currents away from the shoreline or along the shoreline, so behavior during early life stages may be directed toward providing access to required habitat in later stages. The precise substrate preference of a cottoid larva at settlement from the plankton may not be the same substrate preference as an adult, but it will be a substrate that is a component of the adult habitat. Thus, growth stages shift only their relative position on the seabed within a general habitat.

Niche partitioning between species in terms of habitat preference (as with food preference) is examined for mechanisms that allow ecological separation that could have led to speciation. Again, interpretation often focuses only on adults. In addition, intertidal studies of cottids have led to different interpretations of competition than subtidal studies. The flathead sculpin, Artedius lateralis, and the padded sculpin, Artedius fenestralis, occupy very similar habitats in the rocky intertidal, yet their larvae occupy different depth ranges along the shoreline. The flathead sculpin settles from the plankton in surface waters, directly onto substrates in the intertidal, whereas larvae of the padded sculpin occupy slightly deeper water, so that they settle subtidally. Thus, habitat preferences in terms of depth provide ecological segregation of these two cottid species during the larval and early juvenile stages. Adults of these species do not necessarily have to display any behavioral differentiation in order for their speciation to be explained.

Behavior

As mentioned, developmental stages of a species may be expected to shift behavior, even though most investigation concerns only the adult stage. Since cottoid and hexagrammoid fishes lack a swim bladder, the planktonic larval and pelagic juvenile stage (if occurring) need to display behavioral solutions to negative buoyancy. In some species those behaviors reflect morphological specializations for the particular life stage, but other species may simply have to swim very energetically, which will affect food requirements and feeding behavior. Schooling only occurs in adults of some of the few pelagic species in these taxa, but larval stages appear capable of schooling in many of the species observed in aquarium settings.

The cryptic appearance of most cottoids, together with bottom dwelling habits, leads to predation threats that require adaptive behaviors. Chance observations have led to the discovery that the tadpole sculpin, Psychrolutes paradoxus, apparently has an emetic flavor that causes predators to cough them out upon ingestion. This species relies first on its cryptic appearance to prevent predation, then secondarily upon its noxious taste to cause rejection by predators.

Even though cottoids lack a swim bladder, they have big extrinsic swim bladder muscles. The buffalo sculpin, Enophrys bison, vibrates when grasped. Another defense behavior in this and other species is the flaring of the gill cover (with the bony suborbital stay) to expose spines that could deter ingestion.

Homing behavior is well documented in cottids that inhabit tidepools. Tagging studies have not been directed as much at subtidal species, but the demonstration of topographic familiarity in tidepool species may extend to other species inhabiting subtidal reefs with significant landmarks.

The existence of homing behavior proves that learned familiarity with surrounding habitat is of significant survival value and that these fish are capable of exploiting that sort of advantage. Seasonal migrations encompass developmental shifts in habitat preference of young stages as well as reproductive behavior of adults.

Feeding ecology and diet

Because the many cryptic species of cottoid and hexagrammoid fishes tend to hide on the bottom of the sea, their feeding habits reflect the closeness of their prey species, which frequently include crustaceans such as amphipods, crabs, or shrimp. The functional morphology of the diverse mouth types in these taxa have been investigated in detail. Most studies of community feeding ecology in these fishes have been conducted with tidepool species.

In terms of mouth types, these fishes tend to feed either by pouncing on and engulfing their prey (ramming) or by drawing the prey into their mouth together with a stream of water by means of very rapid expansion of the gill covers (sucking). The third major type of prey capture in fishes (biting off a piece of a prey) is less well documented in cottoid and hexagrammoid fishes as a strict mode of feeding, although worms as prey may require biting behavior. Species that feed by suction tend to have small mouth openings, whereas species that engulf their prey have large, broad mouths. Different species can combine aspects of these different types of feeding behavior, and relative effectiveness of capture methods influences dietary preferences.

Beyond ingestion of prey, manipulation may be required to enable digestion. In Asemichthys taylori the vomerine teeth of the upper jaw are modified to enable punching holes in the shells of snail or clam prey so that soft tissues can be digested.

Two cottid species have been documented as switching to a substantially herbivorous diet as adults. These two species, Enophrys bison (buffalo sculpin) and Clinocottus globiceps (mosshead sculpin), have only been documented in terms of their gut contents. Gut morphology and digestive mechanisms such as gut acidity have not been studied in detail for these species. Ingestion of some seaweed may accompany predation on crustaceans inhabiting those seaweeds, but gut contents in these two sculpins, as in other taxa, can show the seaweed itself to be the preferred item. In the mosshead sculpin, the biting behavior that enables it to consume algae also enables it to remove pieces of tentacles from intertidal sea anemones (which have algae cells in their tissues).

The large eyes of most cottoid and hexagrammoid fishes would aid in detection of prey in very dim light. The sense of distant touch (lateral line and head canal system), however, enable detection of movement by potential prey in the vicinity of the fish. Psychrolutid fishes have particularly well-developed head canals with large pores. In the Agonidae, various species have the lower rays of their pectoral fins elongated beyond the webbing of the fin, so that they can rake through sand and gravel with these rays much as if they were fingers. Whether movement of the prey they disrupt and ingest is detected by these fin rays or by distant touch is not known. Many morphological features of these fishes probably relate to feeding adaptations.

In terms of predators, little is known about predation of the less common species such as the skilfish, but the larger of these bottom-dwelling species tend to be prey to larger fishes (like lingcod) as well as to seals and sea lions. Sablefishes are quite cannibalistic, as are lingcod.

Reproductive biology

Most greenlings, sculpins, and related species lay adhesive masses of eggs that either adhere to rocky substrate, cluster around plant or animal stalks and tubes, or are wedged into crevices. The eggs always adhere to each other, but not always to the spawning substrate. Among the sculpin relatives, only the comephorid sculpins of Lake Baikal give live birth to hatched larvae. Perhaps the most remarkable reproductive specialization among cottoid fishes is the phenomenon of internal gametic association, which has been demonstrated for sculpins (Munehara et al., 1997) and poachers (Munehara, 1997). With internal gametic association, the fishes copulate, but the sperm does not fertilize the egg until introduced to the calcium ions in seawater. This enables a female to repeatedly deposit small egg masses in specific ways over a long period of time, up to dozens or hundreds of depositions over weeks of time, based on one mating. Many highly specialized spawning substrates have evolved in various cottoid species, perhaps on the basis of internal gametic association in more cases than have yet been demonstrated. Proof of internal gametic association merely requires dissection of eggs from ovaries and placement in seawater, then incubation and observation for embryonic development.

Another typical characteristic of sculpin reproduction is the guarding of a cluster of different egg masses by a single territorial male. Male greenlings and lingcod also guard one or more egg masses. In some sculpins, however, the male exhibits haremic behavior in which both the nest site and a group of females are guarded together. In haremic species there is no evidence yet of internal gametic association. With the scalyhead sculpin, Artedius harringtoni, this author, while diving, observed several rotund little fish, presumed females, dart inside the empty shell of a giant barnacle, immediately followed by a much larger individual, presumed male, which curled its body and spread its fins to close off entry to the barnacle shell. This species lays its eggs inside giant barnacle shells, and there are typically several different colors of egg mass. Females of various sculpin species lay only one of various characteristic colors of egg. In haremic species of the genus Artedius, a cluster of egg masses may number over a dozen masses, but only with a few different colors of egg mass, corresponding to the number of females in the harem. In other genera (e.g. Scorpaenichthys, Enophrys, Hemilepidotus) where the male guards clusters of egg masses of differing colors, it is not known whether haremic behavior is involved, because groups of females have not been observed remaining near the guarding male.

Whereas haremic species tend to lay egg masses that adhere to a rock surface or to previously laid egg masses in a cluster at the guarded nest site, species with internal gametic association tend to lay smaller egg masses of less characteristic size. That is, the female can extrude whatever number of eggs is required to fill an interstitial space or to form a ring around a stalk, then move on to search for another deposition site, the sites being dispersed according to availability. In agonid species there appears to be a tendency to spawn inside sponges, whereas liparidid species tend to spawn in seaweeds or inside shells.

As much as the spawning characteristics vary among sculpins and relatives, their larvae also demonstrate diverse adaptations. Lacking a swimbladder at any stage, these species have evolved diverse mechanisms to enable early growth while inhabiting the water column. Enlarged pectoral fins exist in larvae of many species, whereas larvae of other species have a flaccid, globular body with relatively large volumes of lowdensity, buoyant body fluid.

Conservation status

Of the families covered in this chapter, the IUCN 2002 Red List includes nine species of the genus Cottus: one is categorized as Extinct (C. echinatus); two as Critically Endangered; four as Vulnerable; and two as Data Deficient. Sculpins and greenlings tend to inhabit rocky, marine shorelines that are less subject to alteration by human activities than estuarine habitats. For a species like the staghorn sculpin (Leptocottus armatus), which uses estuaries as nursery habitat for juveniles, habitat loss can affect populations locally, but the species as a whole is widespread and abundant. For many species that are rarely encountered by people, too little is known of habitat or true abundance to enable determination of conservation status. Where human developments eliminate all natural shoreline, as in municipal harbor areas, intertidal fish species generally lose their natural abundance. It is not known whether greenlings and sculpins are any more sensitive to pollution than other marine fish species. In freshwater lakes and streams, sculpins tend to be depleted both by habitat destruction and by introduction of alien species, as well as by pollution. The widespread distribution of various species of Cottus has prevented extinction from occurring at the species level, but geographically significant populations do become threatened.

Only a limited number of these fishes are directly sought in fisheries as food for humans. In the cases of the cabezon (Scorpaenichthys marmoratus), the sablefish (Anoplopoma fimbria), and the lingcod (Ophiodon elongatus), commercial fisheries have led to localized depletion that has necessitated fishing restrictions. In the cases of the cabezon and the lingcod, extended periods of restricted fishing have not led to population recoveries to original levels of abundance. Overexploitation has tended to occur first in more densely populated areas along inland seas and more southerly waters of the Pacific coast of North America.

A recent trend in North Pacific fisheries is to land live fishes for Asian markets. The lack of a swimbladder and bottom-dwelling habits render species of greenling and sculpin hardy in this trade. In addition, the head and skeleton are recovered after filleting and used in making soup stock, so that sculpins with large heads are marketable in the live trade. Greenlings and larger sculpins that are of little value in traditional fisheries are becoming increasingly exploited for live seafood trade, owing to the higher prices paid for live fish.

Significance to humans

The most obvious significance to humans of greenlings and sculpins is the importance as food of the few commercially sought species. Before the availability of ice or refrigeration systems, the lingcod (Ophiodon elongatus) was the target of fishing with hook and line by boats with flooded holds for keeping the fish live (and therefore fresh) until delivery to processing plants. The lack of a swimbladder enabled keeping the lingcod alive during extended fishing trips.

Diversification of fish farming that currently involves salmon species may soon include various relatives of greenlings. The sablefish or Alaska blackcod, Anoplopoma fimbria, is the subject of aquaculture research in British Columbia, and at the turn of the millennium the first commercially produced, cultured fingerlings were being grown to market size by salmon farmers.

The unusual body forms of various sculpins and related fishes lends aesthetic value to them. They are popular species for display in public aquariums. Seacoast tourism depends to some extent on the attraction people feel toward exploring tidepools along rocky shores, and intertidal sculpins are among the most readily observed species. Marine biological research has long encompassed study of intertidal sculpins because of their accessibility, and to a similar extent, because of their robust ability to withstand manipulation like tagging or maintenance in aquarium tanks.

Species accounts

List of Species

Rockhead

Bothragonus swani

family

Agonidae

taxonomy

Bothragonus swani Steindachner, 1877, previously called Bothragonus swanii, Port Townsend, Puget Sound, Washington, United States.

other common names

English: Pithead poacher, pit-headed poacher, pitted poacher, deep-pitted poacher, deep-pitted sea-poacher.

physical characteristics

Short, stout body of 3.5 in (9 cm), covered with armor plates and with small fins other than the pectorals. Like other poachers (Agonidae), all fin rays are unbranched, and tail bones are fused. The rockhead, or pithead poacher, is most obvious for its wide, flattened head with a deep indentation in the top. Eyes and mouth are small. As a larva, the pectoral fins become enlarged like butterfly wings, and the body is covered with fine spines. The pelagic juvenile develops heavier, recurved body spines that hook toward the tail. These sharp hooks flatten into armor plates after settlement to the bottom.

distribution

Northern California to Kodiak Island, Alaska.

habitat

Rocky shorelines exposed to waves, down to 66 ft (20 m) depth. Found under rocks, in crevices, or among kelp holdfasts.

behavior

Very little is known of this elusive fish. When first settled, the hooked body plates serve to prevent the fish from being washed backward by wave surge. It is not known whether the adult braces itself against overhead rock protrusions with the pit in its head. This poacher relies on close hiding quarters and cryptic appearance rather than flight, for predator evasion. If picked up, it vibrates.

feeding ecology and diet

Larval rockheads tend to feed on copepods or fish larvae. Adult rockheads feed on small crustaceans.

reproductive biology

Orange eggs are deposited within a kelp holdfast. It is not known whether copulation and internal gametic association are required to permit the female to extrude eggs into such interstitial spaces.

conservation status

Not listed by the IUCN. This poacher is too rarely encountered to permit evaluation, but the exposed, rocky shorelines it inhabits tend not to face human development.

significance to humans

The rockhead is not sought for any purpose and is only rarely displayed in aquariums, since it tends to hide from view. It is poorly studied.

Sablefish

Anoplopoma fimbria

family

Anoplopomatidae

taxonomy

Anoplopoma fimbria Pallas, 1811, San Francisco, United States. Family Anoplopomatidae placed either within suborder Hexagrammoidei or suborder Anoplopomatoidei.

other common names

English: Blackcod, Alaska blackcod, coalfish.

physical characteristics

Sablefishes have separate dorsal fins of equal size and a forked tail fin on a streamlined body of gray to black color. Sablefishes grow up to 42 in (107 cm) in length and over 125 lb (57 kg) in weight.

distribution

Deep, offshore waters of the North Pacific, from Baja California (Mexico), to the Bering Sea, and across to southern Japan. Sablefishes range thousands of miles during their lives and occur at depths of over a thousand feet, abundant down to 3,000 ft (914 m). Their young occur in more inshore waters.

habitat

Open, deep ocean water of the North Pacific. They often feed near the bottom in association with deep-sea fishes like rattails and grenadiers.

behavior

Sablefishes swim at relaxed speeds and approach and school with fishes of other species, sometimes as a prelude to a sideways lunge for a head-first swallowing of the unsuspecting prey. They cannibalize their young when they are abundant in inshore waters.

feeding ecology and diet

Sablefishes eat crustaceans, worms, small fishes, and any larger fishes they can capture, which can include salmon almost as long as the sablefish.

reproductive biology

Spawning occurs during winter, and the pelagic eggs float in deep water of about 3,000 ft (914 m) where seawater remains constantly cold. Larvae hatch before functional eyes, jaws, or gut have formed and remain deep until absorbing their large yolk. Larvae with large pectoral fins grow in surface waters during spring.

conservation status

Not listed by the IUCN. Heavily fished through the last century by American, Canadian, Russian, and Japanese longliners and trawlers, sablefishes are now recognized as a depleted species. Catch quotas are now a small fraction of the peak landings that occurred during the middle of the last century. Russian landings from the Bering Sea were reported to have been 38 million pounds (17,000 metric tons) during 1967. Canadian landings at that time were lowest, around one million pounds (454 metric tons).

significance to humans

Sablefishes have been valued greatly as a smoked fish (smoked Alaska blackcod). Their flesh is quite oily. Native North Americans sundried the sablefish. Because they adapt well to living in tanks and net pens, blackcod are being developed as a high-value species for diversification of salmon farms.

Skilfish

Erilepis zonifer

family

Anoplopomatidae

taxonomy

Erilepis zonifer Lockington, 1880, Monterey, California, United States. This species is sometimes placed alone in the family Erilepidae in the suborder Anoplopomatoidei, but the more accepted classification puts them together with sablefishes in the Anoplopomatidae and within the Hexagrammoidei.

other common names

None known.

physical characteristics

The largest of the greenlings and sculpins, skilfishes resemble a heavier version of a sablefish with mottled blue of dark and light shades. Older fishes reach 70 in (178 cm) length and 200 lb (91 kg) weight.

distribution

Deep water of the North Pacific from Monterey Bay, California, to central Honshu Island, Japan and north to the Gulf of Alaska and Kamchatka.

habitat

Young are sometimes caught in offshore, surface waters. Adults are typically caught in deeper water.

behavior

Not known.

feeding ecology and diet

Not known.

reproductive biology

Not known.

conservation status

Not listed by the IUCN. Little is known of the behavior, food habits, or reproduction of this species. It is not the subject of directed fisheries, so there is little basis for determining whether incidental bycatch in other high seas fisheries might have detrimental impact upon the abundance of the skilfish.

significance to humans

None known.

Sailfin sculpin

Nautichthys oculofasciatus

family

Cottidae

taxonomy

Nautichthys oculofasciatus Girard, 1857, Fort Steilacoom, Puget Sound, Washington, United States. Has been listed as Nautichthys oculo-fasciatus and has been segregated from the Cottidae into the family Hemitripteridae on the basis of scales modified into embedded spines.

other common names

English: Sailor fish.

physical characteristics

The elongated rays of the first dorsal fin and the long second dorsal and anal fins, together with a dark bar through the eye joining a dark flap of skin over each eye, cause the cream or brown sailfin sculpin to appear very cryptic, especially among seaweed. Sailfins reach 8 in (20 cm).

distribution

From southern California to the Sea of Okhotsk.

habitat

Sailfins live on rocky reefs and outcroppings, and on adjacent sand bottom, from shallow water down to over 360 ft (110 m) depth.

behavior

In shallow water, the sailfin sculpin waves its first dorsal fin back and forth in synchrony with the motion of adjacent seaweeds in the surge. Between waves of the dorsal fin, the sailfin hops forward by rippling the second dorsal fin and sculling with the pectoral fins. In captivity, sailfins that have never experienced any surge perform the same combination of hopping forward between sweeps of the first dorsal fin. This disruptive mimicry of seaweed obscures the movement of the fish and may enable close approach to prey. This species is nocturnally active.

feeding ecology and diet

Feeds on small shrimps and other crustaceans. Individuals slowly approach their prey prior to hopping forward and engulfing them.

reproductive biology

Sailfin sculpins copulate, and internal gametic association enables the female to repeatedly extrude the bright orange eggs into interstitial spaces among mussels in the intertidal over a period of weeks during winter. The female must migrate into shallow water during high tides in order to reach the mussel beds, where the eggs are periodically exposed to air but are kept cool and damp by the mussels. Larval sailfin sculpins develop extremely elongate pectoral fins that are spread like butterfly wings and used to glide down through the water column while the larva forages on zooplankton. This behavior enables sailfin sculpins to reach relatively large sizes before permanently settling during late spring.

conservation status

Not listed by the IUCN. Elimination of mussel beds by harvesting or pollution will limit the reproduction of the sailfin sculpin, but the small fish is not directly taken for any purpose other than use in aquarium displays. As with the grunt sculpin, larvae of the sailfin sculpin are easily cultured.

significance to humans

Sailfin sculpins are popular with night divers and as display species in public aquariums.

Tidepool sculpin

Oligocottus maculosus

family

Cottidae

taxonomy

Oligocottus maculosus Girard, 1856, Neah Bay, Washington, United States.

other common names

English: Tidepool johnny.

physical characteristics

Typical sculpin body form, with a small, elongate body, to 2 in (5.1 cm), and a relatively large head. Tidepool sculpins have varying numbers and sizes of cirri on their body, singly or in pairs, especially in the head region. They have one forked cheek spine. Color is banded light and dark gray, sometimes with red or green shades. Newly settled young have red fin rays on the tail.

distribution

Coastal waters from the Los Angeles Bight to the Bering Sea and the Sea of Okhotsk.

habitat

Many scientific studies of tidepool sculpins living in tidepools have led to the opinion that this species is an obligate dweller of tidepools. Ironically, spawning is much more dense in protected areas without tidepools than on exposed headlands where pools are formed. Furthermore, tidepool sculpins are abundant in inlets where no tidepools occur, and they strand under rocks during low tides in areas without tidepools. Thus, the tidepool sculpin is a facultative inhabitant of tidepools where they occur, but does not require them to make a living.

behavior

When it occurs in tidepools, the tidepool sculpin exhibits homing behavior when displaced from a home pool. The sense of smell appears to assist in home site recognition.

feeding ecology and diet

Small crustaceans like amphipods or harpacticoid copepods.

reproductive biology

Although it is not known whether this species has internal gametic association, the female mates and then deposits egg clusters in spaces between barnacles or mussels. The eggs are either emerald green, dark green, or maroon. Maroon eggs are laid on shores exposed to wave action, but the same females, removed from exposed shores, in captivity lay green eggs the next season. On small stretches of shore that either gradate or abruptly shift from wave exposure to protection from waves, the proportion of maroon to emerald eggs similarly gradates or shifts abruptly. The egg pigment may reflect some physiological response of the female to the gas saturation of the seawater, but the subject remains a mystery, as does the polymorphism for egg color in many other sculpin species.

conservation status

Not threatened. This is the most abundant and commonly occurring shoreline fish in many parts of the Pacific Northwest. It would probably be one of the last species to disappear in the face of environmental degradation.

significance to humans

The tidepool sculpin is the most easily observed fish in many tidepools, and it has been of great interest to students of intertidal biology.

Grunt sculpin

Rhamphocottus richardsoni

family

Cottidae

taxonomy

Rhamphocottus richardsoni Günther, 1874, Fort Rupert, western North America (Prince Rupert, British Columbia, Canada). Sometimes classified alone in the family Rhamphocottidae.

other common names

English: Grunt-fish, pigfish.

physical characteristics

With a short, stout body and a large head with elongate snout, the resemblance of a grunt sculpin to a pig is only enhanced by

the way it uses its large pectoral fins to scoot around on the seabed. The lower rays of the pectoral fin are elongate and have almost no webbing. The body is covered with small, bristly spines. All of the fin rays are unbranched and the tail bones are fused, as in poachers (Agonidae). These fish grow to 3.3 in (8.3 cm).

distribution

From Santa Barbara, California, to the Bering Sea coast of Alaska.

habitat

Occurs in shallow coastal waters down to 660 ft (200 m) depth, on rocky or shell/sand bottoms, often associated with encrusting invertebrates like giant barnacles.

behavior

The elongate pectoral rays can function like fingers for crawling over coarse surfaces. Grunt sculpins are more frequently observed walking over the seabed than swimming. They hide in empty barnacle shells and may appear to be mimicking live barnacles.

feeding ecology and diet

Video analysis of predation by grunt sculpins reveals a highly adapted method of capturing relatively large shrimp by approaching obliquely, then snapping the head sideways while extending the snout and sucking water in together with the prey.

reproductive biology

Nesting often occurs inside barnacle shells, and controversy exists over whether the female or the male tends the eggs, or whether a mated pair trade off guarding duties. Parental care includes assisting hatching, the parent sucking out hatchlings and spitting them upward into the water. A young female spawns a single mass of eggs in late winter or spring, but with increasing age the females start reproducing with increasing frequency until, at a decade of age, captive females reproduce year-round.

conservation status

Not listed by the IUCN. The only conservation concern relates to possible temporary depletion at popular diving reefs by past collections for display aquariums. Grunt sculpins are easily cultured, however, and most specimens for public display are now propagated in laboratories at major aquariums.

significance to humans

The grunt sculpin is a popular quarry of scuba divers on rocky reefs along the Pacific Northwest. Similarly, they are popular for display in aquariums because of their unusual appearance and interesting habits.

Cabezon

Scorpaenichthys marmoratus

family

Cottidae

taxonomy

Scorpaenichthys marmoratus Ayres, 1854, San Francisco, California, United States. Has at times been separated into its own family, Scorpaenichthyidae.

other common names

English: Giant marbled sculpin, giant sculpin.

physical characteristics

This relatively huge fish (to 30 in [76 cm] and 30 lb [13.6 kg]) has a marbled color pattern that incorporates light and dark gray, brown and beige, or olive green shades. The young often have shades of red. Scales are covered by skin. This is the only sculpin with an unpaired flap of skin on the tip of the snout. The pelagic juvenile is metallic blue, shaped like a blunt-nosed, short salmon smolt.

distribution

Central Baja California, Mexico, to Sitka, southeast Alaska.

habitat

Inhabits rocky reefs from very shallow depths down to the limits of kelp growth, sometimes deeper. They tend to hide in kelp beds, sometimes literally hanging in the seaweed. Juveniles occur in tidepools.

behavior

An ambush predator, the cabezon tends to be sedentary, relying on the camouflage of its coloring. If stranded in kelp during low tide, a cabezon flares its gill covers and holds still. Pelagic juveniles are attracted to turbulence in a laboratory situation, and will strike at prey in the most rapid flows they can find, which may lead them to settle on exposed shorelines.

feeding ecology and diet

Kelp crabs, other crabs, shrimp, snails, clams, worms, or small fish.

reproductive biology

Males guard clusters of egg masses during late winter and spring. The egg masses vary in color from burgundy to purple to dark green. The eggs are toxic to birds and mammals that might otherwise predate on them during low tide exposure. Small sculpins crowd in to predate on cabezon larvae hatching at the edges of the nest site, without the male paying any attention to their activity.

conservation status

Not listed by the IUCN. Cabezons show signs of being overfished through their southern range. Depletion is evident in southern British Columbia, where they are not the target of either sport or commercial fishing, although bycatch landings occur in both fisheries. Commercial setline fishing has been directed at cabezons in California for over half a century, and they are considered a top sport angling species there as well. Cabezon spearfishing is popular because of the ease of spearing these big fish.

significance to humans

The firm flesh of the cabezon is favored by many. It is a popular sport fish with bait anglers, especially in California.

Lumpfish

Cyclopterus lumpus

family

Cyclopteridae

taxonomy

Cyclopterus lumpus Linnaeus, 1758, Baltic Sea and North Sea.

other common names

English: Henfish, lumpsucker; French: Grosse poule de mer.

physical characteristics

Thick body with rows of hard, conical tubercles, and with a soft, cartilaginous hump on the back, embedding the first dorsal fin. The tubercles are in a single row along the back and in three lateral rows on each side. Pelvic fins are modified into a suction disc. The fish is green, gray, blue, or brown, with red highlights on breeding males. Breeding females become distended with eggs. Lumpfishes have reached 2 ft (61 cm) and 21 lb (9.5 kg).

distribution

Across the North Atlantic Ocean from Chesapeake Bay to Hudson Bay, Greenland, Iceland, the White Sea, and south through the British Isles to France.

habitat

This is a bottom fish that inhabits cold waters on rock bottom. Early in life the hatchlings, fully formed as juveniles, are in surface waters, then older juveniles are semipelagic, living under seaweed.

behavior

From the time of hatching, lumpfishes are capable of using their pelvic sucking disc to adhere to smooth surfaces, which tend first to be seaweed blades, then rocks.

feeding ecology and diet

Crustacean plankton like krill, amphipods, and copepods, as well as jellyfishes and small fishes.

reproductive biology

Early in spring the lumpfish female deposits an adhesive egg mass of over 100,000 eggs on rocky bottom among seaweed. Lumpfishes spawn more than one batch of eggs, and hatching occurs from May to July, after six to ten weeks of incubation. Egg color is polymorphic between different females, including colors like brown, red, pink, orange, yellow, green, and purple.

conservation status

Not listed by the IUCN. Early accounts listed the lumpfish as being of no economic value, but they were always a bycatch in the inshore cod trap and gillnet fishery, and their ripe eggs were marketed as caviar starting in the late 1960s. In North America the flesh is sold as dog food, but it is eaten by people in Europe. The eggs are stripped from ripe females and packed in brine for preparation as lumpfish caviar.

Overfishing has occurred. In Newfoundland the catch rate was 229 lb (104 kg) per net per year in 1979 (total landings 85 tonnes) at 16 nets per boat, whereas by 1996 the catch rate was down to 21 lb (9.5 kg) per net per year (total landings still 82 tonnes) at 40 nets per boat, and nearly ten times as many boats in the same region.

significance to humans

With the decline of beluga sturgeon and other traditional sources of caviar, lumpfish caviar has become highly valued.

Kelp greenling

Hexagrammos decagrammus

family

Hexagrammidae

taxonomy

Hexagrammos decagrammus Pallas, 1810, formerly Chiropsis decagrammus Pallas, Cape St. Elias, Alaska, United States.

other common names

English: Tommy cod, speckled sea trout, greenling sea trout.

physical characteristics

Reaches 24 in (61 cm), 4.6 lb (2.1 kg), males smaller. Five lateral lines occur along each side of body, and the male is blue-brown with prominent light blue spots on top of head and anterior body; the female is yellow-brown with small red or orange spots.

distribution

Santa Monica Bay, southern California, to Amchitka Island (Aleutians), Alaska.

habitat

Inhabits shallow, subtidal seabed on rocky shores, often around kelp beds.

behavior

Fairly active; males in particular cruise around a home area during daylight. More aggressive than the whitespotted greenling, Hexagrammos stelleri, which sometimes cohabits with kelp greenlings, the kelp greenling even feeds on unguarded lingcod eggs.

feeding ecology and diet

Small shrimps as well as worms and small fishes.

reproductive biology

Courtship occurs in late fall, with spawning from October through December, eggs hatching in January through February. The male guards the nest site, at which successive females will be courted for spawn deposition. Eggs are blue to purple with a pale center when first laid, becoming golden brown when embryos are eyed. Larval and pelagic juvenile stages last about two months, with these early stages a gun barrel blue, with snub snout shape. Juveniles school over rock faces prior to settlement and metamorphosis to a benthic juvenile resembling the adult. Sexually dimorphic color is evident during the first summer.

conservation status

Not listed by the IUCN. Kelp greenlings are caught as bycatch in hook and line fisheries for live rockfishes, and have achieved their own localized market demand in Asian communities in Vancouver, Seattle, San Francisco, and Los Angeles. Little potential exists for overharvest by sport anglers unless using small tackle, owing to small mouth size. Serious depletion of larger groundfish species could prelude the depletion of greenlings in a localized area, since hook, live market, and line fishery includes landings of greenlings as well as larger groundfishes.

significance to humans

Fillets of kelp greenling are high quality. Kelp greenlings are desired in the retail marketing of live fish (primarily rockfishes). Kelp greenlings are too small to provide enjoyable sport fishing unless light tackle is used, but greenlings are easy to catch and therefore provide good sport for small children.

Lingcod

Ophiodon elongatus

family

Hexagrammidae

taxonomy

Ophiodon elongatus Girard, 1854, San Francisco, California, United States. Sometimes placed in family Ophiodontidae.

other common names

English: Cultus cod, ling.

physical characteristics

Lingcod are large, up to 5 ft (1.5 m) in length and 100 lb (45 kg) weight (males smaller), and have a large mouth extending behind the eyes. The mouth has prominent teeth. The spiny and soft dorsal fins are joined to form one long, moderately notched dorsal fin running the entire length of the body behind the head, and the tail fin is squared, not forked. The color is brown, rarely blue-green, with a staggered array of black blotches along the body midline and top.

distribution

From Ensenada, Mexico (Baja California), to the Alaska Peninsula (Shumigan Islands).

habitat

Lingcod spawn on rocky reefs along the shoreline, usually at depths of about 33–99 ft (10–30 m), but spawning has been observed in the intertidal and by submarine at much greater depths. The females migrate onto sand and mud bottoms at greater depths up to 330 ft or more (100 m), except when they return inshore for spawning, whereas males tend to remain all year on the spawning reefs. Lingcod will hide in crevices. Young lingcod tend to be more generally distributed near the shoreline, avoiding areas occupied by adults. Recently settled lingcod have been collected in eelgrass beds and have been seen from a submarine on flat bottom at the base of a cliff over 360 ft (110 m) deep.

behavior

Aside from male territoriality, female seasonal migrations, and rapacious predatory behavior, lingcod tend to be sedentary ambush predators. They rest near rocks and wait for prey to swim near. During salmon migrations, however, lingcod have been observed predating at the surface over great depths, so relative abundance and position of prey affect behavior.

The life history of lingcod relates closely to that of Pacific herring. Larval lingcod settle from the plankton at the time during spring when herring larvae are becoming silver juveniles. Young lingcod that have not settled permanently from a swimming habit search in school formation during the twilight hours of dawn and dusk, and young herring are their favorite prey.

feeding ecology and diet

Although lingcod will eat invertebrates such as crabs, shrimps, and octopi, they mainly feed on other fishes, including younger lingcod. A lingcod engulfs another fish head-first. The throat rapidly opens while the mouth engulfs the prey, so that a fish about two-thirds the length of the lingcod will be swallowed immediately into the entire length of the stomach, with only the tail protruding from the mouth. During years of abundant prey, growth is rapid. After two years lingcod of both sexes tend to reach about 1.5 ft (46 cm) in length, after which males grow more slowly than females, perhaps owing to the seasonal feeding migration that only females undertake.

reproductive biology

Males become jet black and fight over territory during winter, prior to arrival of ripening females. Males will successively spawn with different females, guarding up to three egg masses at a time. Males are capable of spawning at two years of age, and females at three, but most females do not lay eggs until they are four. If larger females are not abundant, then females tend to mature and spawn a very small egg mass at three years of age. In British Columbia, peak abundance of guarded egg masses is during February, although spawning can occur from December through April. Spawning occurs later in more northerly latitudes. Older females of 10–15 years of age can spawn a half million eggs, and they spawn earlier and deeper than the younger fish. Larvae spawned by the largest females tend to be slightly larger than larvae of small females, which could confer advantage under certain feeding conditions in the plankton. Thus, a population with a full demographic spread from young to old fish will have greater chances of survival of young under a variety of environmental conditions.

conservation status

Not listed by the IUCN. Lingcod have been extremely depleted since the 1980s in Puget Sound, and since the 1990s in the Strait of Georgia. Outer coast populations have become overfished in more recent years. It has been demonstrated mathematically that even the earliest hand-line fisheries prior to World War II led to significant reduction in lingcod biomass in inland seas around Vancouver and Seattle. More efficient otter trawls in the 1940s greatly increased levels of landings, which in British Columbia exceeded eight million pounds per year (over 3,700 metric tons). Landings in the Strait of Georgia were negligible when the commercial fishery closed in 1990, but since then it has become evident that sport fishing alone can prevent population recovery near metropolitan areas. Lingcod are of interest for management strategies that include protection within sanctuaries (marine protected areas).

significance to humans

The common name "cultus" is a Coast Salish term meaning "cheap," which indicates that original levels of abundance ensured that lingcod could be caught for use as food when preferred species like halibut became less available. As mentioned, lingcod has always been valued as a fresh fish. Aquaculture is possible but not yet economical. Appreciation of the value of lingcod as a sport species tends to increase as the availability of this and other groundfish species declines in a given area.

Slipskin snailfish

Liparis fucensis

family

Liparididae

taxonomy

Liparis fucensis Gilbert, 1895, Strait of Juan de Fuca, 109 fathoms. Is classified sometimes within the Cyclopteridae, and the family name Liparididae was formerly Liparidae.

other common names

English: Juan de Fuca liparid.

physical characteristics

This snailfish grows to 7 in (18 cm) and has a lobe at the front of its dorsal fin and the anal fin barely extending onto the tail fin. Color is from brown to olive. Like other snailfish, it has a tadpole shape to the body, large pectoral fins with extended lower rays, and a small pelvic suction disc. Larvae become spherical in a globular bubble of body fluid beneath the skin. Immediately upon settlement there is a metamorphic change (shrinkage) to a snailfish shape like a tadpole.

distribution

Northern California to southeast Alaska.

habitat

Has been collected over a wide range of depths from the shore down to 1,270 ft (388 m).

behavior

The larval stage grows for an extended period in the planktonic realm by means of neutral buoyancy conferred by the globby, bubble shape of the body.

feeding ecology and diet

Small crustaceans including shrimp.

reproductive biology

The male slipskin snailfish guards a cluster of egg masses inside an empty mussel shell during spring. Egg color varies between egg masses, from tan to pink or orange.

conservation status

Not listed by the IUCN. This snailfish is relatively common in occurrence.

significance to humans

None known.

Soft sculpin

Psychrolutes sigalutes

family

Psychrolutidae

taxonomy

Psychrolutes sigalutes Jordan and Starks, 1895, Puget Sound near Port Orchard, Washington, United States. Species is listed as Gilbertidia sigalutes in older species compendiums, and is listed as a member of the family Cottidae.

other common names

None known.

physical characteristics

The soft sculpin has flaccid skin in which the single dorsal fin seems embedded. The lateral line and head canal pores of adults are large and obvious, especially around the jaws and cheeks. Adults are dark brown or translucent beige. Adult males are much larger than females and often have scars over their large heads. Males can approach 3.5 in (9 cm) in length. The pelagic young have relatively larger eyes, no obvious pores, and are purple with orange pectoral fins.

distribution

Coastal waters from Puget Sound, Washington, to the Aleutian Islands, Alaska.

habitat

Larvae of the soft sculpin migrate to feed at the surface at dawn and dusk. Then as pelagic juveniles, they alternate between settling to soft bottom and migrating to the surface on dark nights when surface plankton is abundant. Females grow to 75% of mature body size while exploiting the plankton. Soft sculpins permanently settle during late spring and occupy deep crevices or recesses in multilayered rock rubble, usually on shorelines protected from wave surge.

behavior

The male soft sculpin continues growing after settlement, whereas the female starts developing ripe ovaries. The male is highly territorial, rotating his body in a circle and stuttering his head to keep other males away from his territory. Head biting occurs among males.

feeding ecology and diet

Feeding is visual during early larval stages, then the pelagic juveniles switch to use of distant touch at night as the eyes become relatively smaller and the head canal pores enlarge. Adults in crevices use distant touch to detect crustacean prey like amphipods. Adults cannibalize young soft sculpins that enter their territory.

reproductive biology

The male soft sculpin attracts a harem of several females and courts them in synchrony prior to copulating with each female in sequence. Females simultaneously lay a group, monolayer egg mass on the underside of a rock surface. The females tend the eggs communally, the fanning behavior of one female stimulating similar behavior in adjacent females. The male remains to one side and guards the nest site against other fishes or invertebrates. At hatching, the females suck larvae from the egg shells, swim away from the nest crevice, and spit the larvae toward the surface.

conservation status

Not listed by the IUCN. Detection of soft sculpins tends to occur rarely. It is doubtful whether human activities directly affect this species.

significance to humans

None known.

Resources

Books

Horn, Michael H., Karen L. M. Martin, and Michael A. Chotkowski, eds. Intertidal Fishes: Life in Two Worlds. San Diego: Academic Press, 1999.

Periodicals

Jackson, K. L., and J. S. Nelson. "Ambopthalmos, a New Genus for 'Neophrynichthys' angustus and 'Neophrynichthys' magnicirrus, and the Systematic Interrelationships of the Fathead Sculpins (Cottoidei, Psychrolutidae)." Canadian Journal of Zoology 76 (1998): 1344–1357.

Kirilchik, S. V., and S. Ya. Slobodyanyuk. "Evolution of the Cytochrome b Gene Fragment from Mitochondrial DNA in Some Baikalian and Non-Baikalian Cottoidei fishes." Molecular Biology (Molekulyarnaya Biologiya) 31 (1997): 141–148.

Munehara, H. "The Reproductive Biology and Early Life Stages of Podothecus sachi (Pisces: Agonidae)." Fishery Bulletin 95 (1997): 612–619.

Munehara, H., Y. Koya, Y. Hayakawa, and K. Takano. "Extracellular Environments for the Initiation of External Fertilization and Micropylar Plug Formation in a Cottid Species, Hemitripterus villosus (Pallas) (Scorpaeniformes) with Internal Insemination." Journal of Experimental Marine Biology and Ecology 211 (1997): 279–289.

Wonsettler, A. L., and J. F. Webb. "Morphology and Development of the Multiple Lateral Line Canals on the Trunk in Two Species of Hexagrammos (Scorpaeniformes, Hexagrammidae)." Journal of Morphology 233 (1997): 195–214.

Yabe, M., and T. Uyeno. "Anatomical Description of Normanichthys crockeri (Scorpaeniformes, incertae sedis: Family Normanichthyidae)." Bulletin of Marine Science 58 (1996): 494–510.

Jeffrey Burton Marliave, PhD