Animal Diversity Web

Geographic Range

The northern searobin can be found from within the width of the continental shelf from New York to Cape Hatteras, North Carolina. (Dalberg 1975; Hoese 1977; Conservation 1996)

• Biogeographic Regions
• nearctic
  • native
• atlantic ocean
  • native

Habitat

Northern searobins are found in the waters (estuaries to the edge of the continental shelf) from New York to Cape Hatteras, North Carolina. They usually keep close to the bottom because they prefer the sandy bottoms of the waterbeds. However, at times they are found close to the surface. They live in waters anywhere from 4.4 degrees Celsius to 18 degrees Celsius. They can tolerate a temperature difference of 13 degrees Celsius. The normal range of temperatures is from 6 degrees Celsius offshore in the winter to 9 degrees Celsius inshore in the summer. Most northern searobins are not found in salinities below 20 o/oo. Few juvenile searobins are found in estuaries. (Conservation 1996;Dalhberg 1975; Hoese 1977; 2000 eNature; Bolke 1993)

• Aquatic Biomes
• coastal

Physical Description

Northern searobins grow to an average of 17 inches long and 43 centimeters. Their shape is long with a round front that thins out as to the back of the fish. The top portion of a Northern searobin is reddish or grayish in color and the bottom portion of the fish is pale. Its head is large with several ridges and spines. As they grow, some of the ridges and spines start to disappear. The chin is black in color. Part of the reason that this fish is called a northern searobin is because the pectoral fins have a wing-like appearance. Fins are reddish-brown, almost black on the top, and grayish-whitish on the bottom. The pelvic fins are white in color. They have a black spot between their 4th and 5th spines on the first dorsal fin. The spiny dorsal fin is triangular shaped, while the anal fins and soft dorsal fins are long in shape.

(Conservation 1996; 2000 eNature; Bolke 1993; Bond 1979; Dahlberg 1975)

• Other Physical Features
• bilateral symmetry

Reproduction

The normal northern searobin reaches reproductive maturity at age two to three years and 85 grams, 200 millimeters in length. Some one-year-old northern searobins can produce eggs; however, fewer eggs are made and the ovaries are small so they are still unable to reproduce. Northern searobins are ripe primarily between July and early September. By November most fish are no longer reproductively ripe. The embryos are similar to those of other summer spawners. When it is mating season, northern searobins produce a staccato call that is different than their usual grunting noise. The fertilization of the eggs is external. The testes are clear white and long. The eggs are invisible to the eye. The ovaries are between a yellow or orange color. When the ovaries are ripe, the eggs become visible to the eye. They are triangular in shape, with a few blood vessels. Very few eggs are ripe at any one time, which is why the breeding season is prolonged. The average egg size is 0.2 mm to 1.0mm.

Eggs are found in 22 degrees Celsius water and will hatch in 60 hours. Current research being performed by McBride and Able (1994) shows differences in the reproductive location between Prionotus carolinus and Prionotus evolans. Prionotus evolans are usually found in estuaries and the inner shelf habitats, where Prionotus carolinus are more often found in trawls between July and December. Prionotus carolinus shows up earlier in coastal habitats than Prionotus evolans. Throughout the winter, Prionotus carolinus are scattered throughout the continental shelf while Prionotus evolans are found in the warmer waters.

There is no parental care.

(Conservation 1996; McBride and Able 1994; Tavolga 1977)

Behavior

There is not much information available on the migration of northern searobins for the north-south migration. Northern searobins that are north of Cape Hatteras go inshore during the spring and offshore in the late fall. There is not any evidence that searobins travel in schools as other fish. The northern searobins exhibit strong diggings response especially when they sense old and dead species, which they refer to as food. If the extracts of specimens are fresh then their response is weaker. If the mouth is stimulated, the northern searobins gulp and swallow instead of digging.

(Conservation 1996)

• Key Behaviors
• natatorial
• motile

Communication and Perception

• Perception Channels
• tactile
• chemical

Food Habits

Northern searobins are classified as carnivores. The range of food that they eat is from young herring and shrimp to seaweed and any bait. For adult fish, the main dietary sources of food are amphipoda, gammarus, and different kinds of cumacean, fish,

and eggs. The adults also consumed small amounts of seaweed and sand. The juvenile fish consume mostly the same food as the adults; however, they also consume copepods in large quantities. There is also a larger food diversity found in the younger northern searobins than in the adults.

(Conservation 1996)

Economic Importance for Humans: Positive

Northern searobins are classified in the sport fishery. They are good fighters and are considered good food source like kingfish or whiting. However, they are considered a nuisance because of the spiny structures, so few of them are eaten. Northern searobins are considered trash fish and are often caught only by accident. (Conservation 1996)

Economic Importance for Humans: Negative

There was not any information found of the negative impact of the northern searobin.

Conservation Status

The total allowable catch of other finfish as allowed by the ICNAF is 150,000 tons a year. Northern searobins are categorized as other finfish. Any type of incidental catch is allowed however. (Conservation 1996)

• IUCN Red List [Link]

  Not Evaluated

• US Federal List

  No special status

Other Comments

Northern searobins were originally classified in the genus Trigla. Today, this is the genus for European searobins, not for North American searobins. Some other names for the Northern searobins are: grunter, web-fingered searobin, and gurnard. Lacepede was the first to use the genus Prionotus for the northern searobin. Northern searobins are the most commonly found searobins in the Chesapeake Bay. (Conservation 1996)

Contributors

Patricia Willauer (author), Western Maryland College, Louise a. Paquin (editor), Western Maryland College.

References

2000. "eNature.com" (On-line). Accessed March28,2001 at http://www.enature.com/flashcards.show_flash_card.asp?recordNumber=F10260.

Bohlke, J., C. Chaplin. 1993. Fishes of the Bahamas and Adjacent Tropical Waters Second Edition. Austin: University of Texas Press.

Bond, C. 1979. Biology of Fishes. Corvallis: Saunders College Publishing.

Conservation Management Institute, August 26 1996. "species searobin, northern" (On-line). Accessed March 28, 2001 at http://fwie.fw.vt.edu/www/macsis/lists/m010501.htm.

Dahlberg, M. 1975. Guide to Coastal Fishes fo Georgia and Nearby States. Athens: University of Georgia Press.

Hoese, H., R. Moore. 1977. Fishes of the Gulf of Mexico ,Texas, Louisiana, and Adjacent Waters. College Station: Texas A&M University Press.

McBride, R., K. Able. 1994. Reproductive Seasonality, Distribution, and Abundance fo Prionotus carolinus and P. evolans (Pisces: Triglidae) in the New York Bight. Estuariane, Coastal and Shelf Science, 38: "173-188".

Tavolga, W. 1977. Sound Production in Fishes. Stroidsburg: Dowden, Hutchinson & Ross, Inc..