Shorthorn sculpin Myoxocephalus scorpius (Linnaeus) 1758 ^[73]

DADDY SCULPIN; BLACK SCULPIN; GREENLAND SCULPIN

Description—

The shorthorn sculpin, with its large flat head, vast mouth, weak tapering body, bat-like pectorals, and insatiable appetite, typifies the sculpin race in northern seas. It has a longitudinal ridge with 3 knobs or spines running along each side of its crown; also about 6 (sometimes 5 or 7) short triangular bluntish spines on each side of the cheek between snout and gill opening, the uppermost of these less than twice as long as the one below it, and reaching not much more than halfway to the edge of the gill cover. And there is a short but sharp spine at the upper corner of each gill cover, pointing rearward and lying on a flap of skin, besides two thornlike spines on each shoulder close behind the upper corner of the gill cover.

There is a pore, or small slit, piercing the soft skin low down on each side of the throat close behind the last gill arch, easily seen on large specimens and detectable even on small ones on close examination.

The very large eyes are at least as wide as the space between them, set high up on the sides of the head with the upper edges close to the dorsal profile, and they are directed a little upward as well as outward. The two parts of the dorsal fin are entirely separated by a deep notch, but there is no gap between them. The forward part has 9 to 11 spines, the rear part about 16 or 17 (sometimes 15) soft rays, the longest of which are only a very little longer, if any, than the longest of the spines, each measured from base to tip. The anal fin, with 13 to 14 rays, is similar to the second dorsal in shape, but a little smaller; it originates about under the fourth or fifth soft [page 446] dorsal ray. The caudal fin is small, its rear margin weakly rounded; the fanlike pectorals, of 17 or 18 rays, reach back about as far as the vent. On large specimens the dorsal, anal, and pectoral fins are rather noticeably thick and fleshy. There are two series of prickly plate-like scales along each side of the body, one above the lateral line, the other below it.

Males and females differ in appearance, the former being the more slender, with higher fins, and the more brightly colored. Each of the scales, too, along the lateral line bears three or more prickles in males, but only one or two at the most in females, while some of the latter have no scales. Furthermore, the inner edges of the rays of the pectoral and ventral fins are armed with teeth or prickles on the males but not on the females.

Color—

The basic hue of the upper parts is usually of some shade of brown, ranging from a warm reddish tint to almost black, with the top and sides of the head marked with pale blotches and the back and sides of the body with broad dark bars on individuals on which the ground tint is pale. The lower parts of the sides are more or less spotted with yellow. The belly is whitish or yellowish in females, usually reddish orange with large round white spots in males, this being a good field mark for distinguishing the sexes. The dorsal fins are mottled dark and pale, the second dorsal often marked with 3 or 4 definite crossbars, and the caudal fin with various dark mottlings. The rays of the pectoral and anal fins are yellow with 2 or 3 irregular dark crossbars on many specimens, but they are uniformly dark in some. Males are more brightly colored than females in the breeding season, when their red and yellow tints become very brilliant, and when an intensification of the red or coppery ground color of the belly brings out the white spots more clearly than at other seasons.

Variability—

European studies have shown this to be a highly variable species, tending to break up into local races. Whether this is equally true of it on our side of the Atlantic is not known.^[74]

Size—

This is the largest Gulf of Maine sculpin. It has been said to grow to a length of about 3 feet, but the average run of the adults taken in our Gulf is only about 8 to 14 inches, the longest not more than 2 feet. This species increases in size from south to north, Greenland fish averaging much larger than those taken off New England or off the Maritime Provinces.

Remarks—

Young shorthorns, up to 6 or 7 inches long, resemble the little grubby (p. 443) so closely that they are likely to be confused with it. Points of difference are that the shorthorn has at least 13 or 14 rays in its anal fin, and has a pore piercing each side of the throat close behind the last gill arch, the grubby only 10 or 11 anal rays, and no such pores.

Larger specimens of the shorthorn could hardly be mistaken for any other Gulf of Maine fish, unless perhaps for the longhorn sculpin. And even a cursory look is enough to separate one of these from the other, the upper cheek spine being less than twice as long as the one below it, and not reaching more than halfway to the edge of the gill cover in the shorthorn, but about four times as long as the one below it in the longhorn, and reaching back at least as far as the edge of the gill cover.

Habits—

Bays and the vicinity of ledges that rise from comparatively smooth bottom in shoal water are the chief haunts of the shorthorn sculpin. And it is found indifferently there, on mud, sand, or pebbles, on bare bottom or among weeds. Many are also caught off piers and along our rocky shores by cunner fishermen. Off our coasts, the great majority live shoaler than 10 fathoms. And while a day's fishing on any of the ledges northward and eastward from Cape Cod is likely to yield an occasional shorthorn among other fish, few are caught on long lines set deeper than 15-20 fathoms. The deepest records for it in American waters of which we know are 50 fathoms near Campobello Island, at the mouth of the Bay of Fundy (reported by Huntsman), and 57 fathoms in the northern part of the Gulf of St. Lawrence, just within the Strait of Belle Isle.^[75]

This is a cold-water fish. Even in summer it is the most plentiful at localities and at depths where the temperature is lower than 55°-60° F. In winter it endures temperatures close to the freezing [page 447] point of salt water. We have never heard of one taken in brackish water, at least on our side of the Atlantic. It is a sluggish fish, often to be seen lying motionless, and as a rule, it hugs the bottom so closely that it is hard to tempt one to rise as much as a few feet by dangling a bait over it. Neither does it come to the surface voluntarily, though the surface may drop to the sculpin on the ebbing tide.

Sculpins usually swim slowly with undulating motion, spreading their great pectoral fins like bat's wings. As a rule, they move only a little way when disturbed, but on occasion they can dart ahead with folded "wings."

They are among the most voracious fishes, feeding chiefly on crustaceans, particularly on crabs, of which they are often full, on shrimps, sea urchins, and worms; on the fry of various other fishes; rarely on shellfish. And they are eager scavengers of any kind of refuse, congregating about fish wharves and lobster cars to feast on the debris. Like all sculpins they bite on any bait, and so greedily that we have caught one time and again, thrown it back, and seen it bite again almost as soon as fresh bait reached bottom.

The shorthorn has been described as hiding in dark crevices or among weeds by day, to emerge at night. This, however, has not been our experience, nor did Gill^[76] find it doing so at Grand Manan.

This fish, like the longhorn sculpin, grunts or gurgles when drawn out of the water, particularly when handled, and it is also known to grunt in the water.

We must turn to European sources for the breeding habits of this sculpin, little attention having been paid to this phase of its life by American ichthyologists.^[77] The spawning season is from November to February, both about Woods Hole and in north European waters, with the chief egg production in December, which no doubt applies equally to the Gulf of Maine. At this season the adult sculpins have been described as gathering in schools on sandy or weedy bottom, with the females greatly outnumbering the males.

Discussion has centered about the manner in which the eggs are fertilized, it being generally agreed that this takes place externally as a rule, but that they may be fertilized within the body of the mother in some parts of the Baltic Sea. In either case, the eggs sink^[78] and stick together in irregular spongy masses through which the water circulates, and which retain considerable moisture even if they are left bare by the ebbing tide, as often happens. These egg masses are deposited on sandy bottoms, in pools in the rocks, among seaweeds, or in any crevice or hollow, in a tin can, for instance, or in an old shoe. Sometimes the male makes a nest of seaweed and pebbles, while he has been described as sometimes clasping the egg mass with his pectoral and ventral fins, and he has been photographed so employed.^[79]

The eggs are of varying shades of red or yellow, 1.5 to 2 mm. in diameter. Incubation is so slow (occupying 4 to 12 weeks, according to temperature) that egg masses with advanced embryos have often been found as late in the spring as April or even May. Newly hatched larvae are about 7 to 8 mm. long. In a month they are 10 mm. long and the yolk sac has been absorbed. The young larvae soon rise to the surface, where quantities of them have been taken in tow nets in British waters in March, April, and May. By May and June some have grown to a length of 22 to 25 mm. They abandon their drifting life at about this size, or soon after, for the bottom, and they may be 38 mm. long by July, showing all the distinctive characters of the adult.^[80] This timetable, compiled from European sources, probably applies equally to the Gulf of Maine, for larvae are found as early as February in the Bay of Fundy and thereafter throughout the spring.^[81]

The subsequent rate of growth is not definitely known. But it is probable that this sculpin is 2 or 3 inches long by the end of its first summer, for we have taken a few 2-inch fish in late June on Nantucket Shoals, and 2- to 3¼-inch fish in late September off Boothbay Harbor, Maine. Most of them, it seems, do not mature sexually until they are at least 6 inches long.

General range—

One or another race of this wide ranging fish is known from Great Britain northward along the coasts of Europe; in Arctic seas [page 448] generally, including Spitzbergen, Nova Zembla, north Siberia, West Greenland, and northern Labrador; and southward along the American coast to southern New England; to New Jersey as a stray.

Occurrence in the Gulf of Maine—

This is one of the most familiar of our shore fishes, common all around the entire coast line of the Gulf of Maine; it is not so abundant as the longhorn sculpin (p. 449), but we doubt if there is a suitable situation, Cape Cod to Cape Sable, where some shorthorns are not to be found, except perhaps at the head of the Bay of Fundy.^[82] But they do not run far up estuaries as a rule, and never into brackish water.

The shorthorn has not been reported positively either from Georges Bank or from Browns. Sculpins of some sort, it is true, are so common on the former that otter trawlers often catch from 20 to 100 per haul, and equally so on Browns Bank. But fishermen lump this and the next species together. Also the fact that the few positively identified on the banks have all proved to be longhorns, and the general predilection of the shorthorn for water shoaler than these offshore grounds, makes it doubtful whether it is to be found there in any numbers. Further evidence in this direction (if indirect) is that most of the shorthorns that were taken during the experimental trawlings of the Newfoundland Fisheries Research Commission were from hauls shoaler than 50 fathoms, only one from as deep as 57 fathoms.

Although it is more strictly confined to comparatively shoal water than the longhorn sculpin, the shorthorns are not often seen close to tide mark in summer, except in the Bay of Fundy where the temperature of even the uppermost few feet does not rise above 52°-54° in most summers, and where there are shorthorns of all sizes in very shallow water, in summer as well as at other times of the year.

On the other hand, the shorthorns living around the open shores of the Gulf show no tendency to avoid winter chilling by descending to greater depths in winter, in the Bay of Fundy, for example, where it is very common, Huntsman has characterized it as the only fish that remains near shore during the coldest part of the year; and it has been described as more plentiful along the shores of Massachusetts Bay in winter than in summer, as it certainly is south of Cape Cod. Certain shallow bays, it is true, such as Duxbury Harbor, where broad expanses of flats are exposed at low tide to heating by the sun in summer and to the formation of ice in winter, are an exception to this rule; i. e., the shorthorn sculpins tend to keep to the deeper channels through the coldest part of the winter as well as during the heat of midsummer. But we have found no evidence that they carry out any seasonal migrations more extensive than this. They are, indeed, among the most stationary of Gulf of Maine fishes.

[page 449]

In Scandinavian waters this fish is said to vary widely in abundance from year to year, years of plenty alternating with longer periods of scarcity, but this does not seem to be the case to any noticeable extent in the Gulf of Maine where it is always common.

To the northward and eastward, the shorthorn is common all along the outer coast of Nova Scotia, in 10-30 fathoms, and it has been taken on Banquereau Bank. It has not been reported in the Magdalen and Prince Edward Island shallows in the southern side of the Gulf of St. Lawrence, where summer temperatures are high. But it is to be expected in that side of the Gulf in slightly deeper water, for it is known all along the northern shore of the Gulf, from Anticosti to the Strait of Belle Isle. We find no record of it on the Newfoundland Banks, probably because of the depth of water; neither is any definite information available as to its status along the south coast of Newfoundland. But it is recorded off the east coast, from the trawlings of the Newfoundland Fisheries Research Commission, and along the outer coast of Labrador, at Battle Harbor (just north of the Strait of Belle Isle);^[83] at Rigolet in Hamilton Inlet;^[84] in the vicinity of Nain;^[85] at Fort Chimo, Ungava Bay, and it is widespread in the Hudson Bay region.^[86]

Importance—

All though this is an edible fish and accounted a good one, its appearance and habits will probably close our markets to it as long as other fish are plentiful. Nevertheless, it once was of some commercial importance, being one of the best baits for lobster pots, for which purpose great numbers were speared formerly on the Massachusetts coast in spring, and were caught along the northern coast of the Gulf on hook and line. But very little use is made of them nowadays, if any.