Lepisosteus osseus

Longnose Gar

Type Locality

Virginia (Linnaeus 1758).

Etymology/Derivation of Scientific Name

Lepisosteus, Greek, “bony scale;” osseus, Latin, meaning “of bone” (Pflieger 1997).

Synonymy

Esox osseus Linnaeus 1758

Characters

Maximum size: The angler record, fish recorded at 183 cm, 22.7 kg from the Trinity River, Texas, 30 July 1954 (Walden 1964; Page and Burr 1991).

Coloration: Adult olive to dark green above; whitish below with large round spots on dorsal, anal, and caudal fins. Young distinctly marked with broad brown or blackish midlateral stripe from snout to base of caudal fin, with a prominent white stripe immediately below, and chocolate brown stripe on each side of belly (Becker 1983).

Counts: 57-65 lateral scales; 47-55 predorsal scale rows; 17-24 transverse scale rows; 14-31 gill rakers (Etnier and Starnes 1993).

Body shape: Beak long and narrow, its least width about 12 to 20 times its length; snout more than two-thirds of head length; large teeth in upper jaw in one row on each side (Hubbs et al. 1991) are numerous, villiform, sharp (Becker 1983).

Mouth position: Terminal (Goldstein and Simon 1999).

External morphology: Scales ganoid (rhomboid); tail abbreviate-heterocercal (vertebrae moving into dorsal portion of fin); gill rakers rudimentary, irregularly arranged (Becker 1983).

Distribution (Native and Introduced)

U.S. distribution: Found from Quebec through out the eastern United States southward to the Rio Grande drainage in Texas, Mexico and New Mexico (Hubbs et al. 1991).

Texas distribution: May be found in most Texas Rivers (Hubbs et al. 1991). Warren et al. (2000) list the following drainage units for species distribution in the state: Red River unit (from the mouth upstream to and including the Kiamchi River), Sabine Lake unit (including minor coastal drainages west to Galveston Bay), Galveston Bay unit (including minor coastal drainages west to mouth of Brazos River), Brazos River unit, Colorado River unit, San Antonio Bay unit (including minor coastal drainages west of mouth of Colorado River to mouth of Nueces River), Nueces River unit.

Abundance/Conservation status (Federal, State, NGO)

Populations in southern drainages are currently stable (Warren et al. 2000).

Habitat Associations

Macrohabitat: Larger streams and coastal inlets throughout range; occasionally found in marine coastal waters (Wiley 1980); occurs in large rivers, reservoirs, swamps and oxbow lakes, and may be expected in small rivers during spawning season (Etnier and Starnes 1993).

Mesohabitat: Fresh and brackish waters (Wiley 1980). Young gars commonly taken in shallows, moving to deeper water as they grow larger and perhaps becoming more nocturnal (Haase 1969). During daylight hours, most time spent resting motionlessly near submerged or overhanging objects close to shore (Echelle and Riggs 1972). At night, commonly found swimming actively in shallow, open waters. Species prefers high water temperatures; has been captured in water temperature of 33.9 degrees C (Becker 1983). In Texas, species commonly found in the Brazos River channel and may periodically dominate oxbows (i.e. Big Bend Oxbow) that connect to the active channel, though they are rare in oxbow lakes during other periods. During the June 2004 flood, species was abundant in Big Bend oxbow, but rare during subsequent surveys; this may occur when gar enter oxbows during floods to forage (gar species in the Brazos River feed selectively on clupeids which are apparently more abundant in oxbow habitats) and then return to river as water levels fall (Winemiller et al. 2004).

Biology

Spawning season: In the spring; typically when water temperature is between 17.8 to 21.11°C (Dean 1895; Netsch and Witt 1962). In freshwater, breeding may occur between March and August, depending on geographic location (Carlander 1969; Wiley 1980).

Spawning Habitat: Nonguarders; open substratum spawners; phytolithophils: nonobligatory plant spawner that deposit eggs on submerged items, have late hatching larvae with cement glands in free embryos, have larvae with moderately developed respiratory structures, and have larvae that are photophobic (Simon 1999; Balon 1981). In Wisconsin, spawning occurred on a shallow gravel bar in water 0.3-0.9 m deep, bulrushes were present; spawning also occurred in water 2 m deep over substrate of boulders (Haase 1969). Spawning occurs in gravel shoal areas and among rocks (Dean 1895; Yeager and Bryant 1983); also in the weedy shallows of lakes and rivers (Echelle and Riggs 1972). It has been found that interspecific nest utilization occurs, as longnose gar have been found to deposit their eggs into smallmouth bass (Micropterus dolomieu) redds, presumable to exploit the brood care afforded by the smallmouth bass (Goff 1984).

Spawning Behavior: Females spawn following a period of circling in shallow water with several males, and they will migrate to spawn in pools. Eggs are shed in repeated batches and are fertilized with a persistent cloud of milt, usually over a substrate of rocky fragments and short stems of aquatic vegetation. Species does not display parental care of eggs or larvae (Dean 1895; Goff 1984). Detailed spawning reported by Haase (1969).

Fecundity: Multiple clutch spawners (Goff 1984). Depending on size of female, from 1,110-77,156 eggs laid; eggs are green and range from 2.1-5.5 mm diameter; incubation period 7-9 days, varying with water temperature; emerging sac-fry will attach to submerged objects by adhesive yolk structure, remaining inactive until yolk sac is absorbed (Haase 1969; Echelle and Riggs 1972, Sublette et al. 1990). Yeager and Bryant (1983) reported that eggs hatched in 3 days at 26 degrees C.

Age at maturation: Males mature at three to four years, females at six (Netsch and Witt 1962).

Migration: Have been known to move inshore to shallow water or upstream to spawn in pools as far as 10 km. Instream residence has been recorded from 15-94 days, with males having longer residence times than females (Yeager and Bryant 1983; Johnson and Noltie 1996).

Growth and Population Structure: Growth rapid during first year of life: In aquariums, Echelle and Riggs (1972) noted average growth of 3.2 mm/day; in Michigan, Hubbs (1921) reported estimated daily growth of 2.33 mm; in Wisconsin, Haase (1969) reported growth of 1.5 mm/day. In Wisconsin, young-of-year reached a maximum of 460 mm TL and one-half of maximum growth in length was attained during the first 2-3 years of life (Haase 1969). In central Missouri, Netsch and Witt (1962) determined age and growth from branchiostegal rays: Age-1 males were 49.5 cm long, females were 55.9 cm; females continue to grow approximately 25 mm/year for 13-14 years; females average 64 mm longer than males, at the end of the first year; disparity in size increases with age to a point where females are 178 mm longer than males at the end of 11^th year of life. Yeager and Bryant (1983) reported larvae 8.8-9.9 mm at hatching.

Longevity: Haase (1969) recorded a 32-year-old female from Lake Mendota, Wisconsin, and reported males up to 27 years old from the same location. Females outlive males (Netsch and Witt 1962).

Food habits: Trophic classifications and mode: carnivore; whole body (piscivore); ambush (Goldstein and Simon 1999). In Texas, the diet of Lepisosteus osseus specimens collected included sunfishes, catfish, crayfish, mullets (Mugil), Moxostoma congestum, and Dorosoma cepedianum (Bonham 1941). Main food items are fishes such as carp, silverside, bluegill, gar, largemouth and smallmouth bass, darters, spottail shiner, killifish, black crappie, blackstripe topminnow, sand shiner, cisco and white bass (Haase 1969; Cahn 1927; Goldstein and Simon 1999). In Mississippi coastal waters, heavy predation on the menhaden reported (Goodyear 1967). Young to 50 mm TL eat invertebrates. Brackish-water individuals reported to also eat crabs (Carlander 1969; Wiley 1980).

Phylogeny and morphologically similar fishes

      Lepisosteus osseus specimens larger than 6 inches are not likely to be confused with L. platostomus and L. octulatus, being can be distinguished from by their extremely long snout (versus much shorter, wider snouts; Hubbs et al. 1991; Page and Burr 1991; Etnier and Starnes 1993). Smaller juveniles of these three gar species have similar bold color patterns, but Suttkus (1963) indicated that the dark lateral band of L. osseus is scalloped on its dorsal margin (straight in L. oculatus) and the middorsal stripe is cinnamon colored and narrow (broader and darker in L. oculatus; Etnier and Starnes 1993).

Host Records

Trematoda (2); Cestoda (1); Nematoda (3); Acanthocephala; Crustacea (Hoffman 1967; Mayberry 2000).

Commercial or Environmental Importance

[Additional literature noting collection of this species from Texas locations includes, but is not limited to the following: Lower Rio Grande (Robinson 1959); Brazos River (Linam et al. 1994).]

References

Balon, E.K. 1981. Additions and amendments to the classification of reproductive styles in fishes. Environmental Biology of Fishes 6:377-389.

Becker, G.C. 1983. Fishes of Wisconsin. The University of Wisconsin Press, Madison. 1052 pp.

Bonham, K. 1941. Food of gars in Texas. Transactions of the American Fisheries Society 70(1):356-362.

Cahn, A.R. 1927. An ecological study of the southern Wisconsin fishes. The brook silverside (Labidesthes sicculus) and the cisco (Leucichthys artedi) in their relations to the region. Ill. Biol. Monogr. 11(1):1-151.

Carlander, K.D. 1969. Handbook of Freshwater Fishery Biology. Volume 1. The Iowa State University Press, Ames. 752 pp.

Dean, B. 1895. The early development of gar-pike and sturgeon. J. Morph. 11:1-62.

Echelle, A.A., and C.D. Riggs. 1972. Aspects of the early life history of gars (Lepisosteus) in Lake Texoma. Trans. Amer. Fish. Soc. 101(1):106-112.

Etnier, D.A., and W.C Starnes. 1993. The Fishes of Tennessee. The University of Tennessee Press, Knoxville. 681 pp.

Goff, G. P. 1984. Brood care of longnose gar (Lepisosteus osseus) by smallmouth bass (Micropterus dolomieu). Copeia. 1984: 149-152.

Goldstein, R.M., and T.P. Simon. 1999. Toward a united definition of guild structure for feeding ecology of North American freshwater fishes. pp. 123-202 in T.P. Simon, editor. Assessing the sustainability and biological integrity of water resources using fish communities. CRC Press, Boca Raton, Florida.

Goodyear, C.P. 1967. Feeding habits of three species of gars, Lepisosteus, along the Mississippi Gulf Coast. Trans. Amer. Fish. Soc. 96:297-300.

Haase, B.L. 1969. An ecological life history of the longnose gar, Lepisosteus osseus (Linnaeus), in Lake Mendota and in several other lakes of southern Wisconsin. University of Wisconsin, Madison. PhD Thesis. 224 pp.

Hoffman, Glenn L. 1967. Parasites of North American Freshwater Fishes. University of California Press, Berkeley, 486 pp.

Hubbs, C.L. 1921. An ecological study of the life history of the fresh-water fish Labidesthes sicculus. Ecology 2(4):262-276.

Hubbs, C., R.J. Edwards and G.P. Garret. 1991. An annotated checklist of freshwater fishes of Texas, with key to identification of species. Texas Journal of Science, Supplement 43(4):1-56

Johnson, B. L. and D. B. Noltie. 1996. Migratory dynamics of stream-dwelling Longnose gar (Lepisosteus osseus). Ecology of Freshwater Fish. 5: 97-107.

Linam, G.W., J.C. Henson, and M.A. Webb. 1994. A fisheries inventory and assessment of Allens Creek and the Brazos River, Austin Count, Texas. River Studies Report No. 12, Texas Parks and Wildlife Department, Austin. 13 pp.

Linnaeus, C. 1758. Systema naturae. 10^th ed., Pt. 1, Paris. 824 pp.

Mayberry, L. F., A. G. Canaris, and J. R. Bristol. 2000. Bibliography of parasites and vertebrate host in Arizona, New Mexico, and Texas (1893-1984). University of Nebraska Harold W. Manter Laboratory of Parasitology Web Server pp. 1-100.

Netcsh, N. F., and A. Witt, Jr. 1962. Contributions to the life history of the longnose gar (Lepisosteus osseus) in Missouri. Trans. Amer. Fish. Soc. 91:251-262.

Page, L. M., and B. M. Burr. 1991. A Field Guide to Freshwater Fishes of North America, north of Mexico. Houghton Mifflin Company, Boston, 432 pp.

Pflieger, W. L. 1997. The Fishes of Missouri. Missouri Department of Conservation, Jefferson City, 372 pp.

Robison, D.T. 1959. The Ichthyofauna of the Lower Rio Grande, Texas and Mexico. Copeia 1959(3):253-256.

Simon, T. P. 1999. Assessment of Balon’s reproductive guilds with application to Midwestern North American Freshwater Fishes, pp. 97-121. In: Simon, T.L. (ed.). Assessing the sustainability and biological integrity of water resources using fish communities. CRC Press. Boca Raton, Florida. 671 pp.

Sublette, J.E., M.D. Hatch, and M. Sublette. 1990. The Fishes of New Mexico. University of Albuquerque Press, Albuquerque. 393 pp.

Suttkus, R.D. 1963. Order Lepisostei, pp. 61-88, In: H.B. Bigelow and W.C. Schroder, eds. Fishes of the Western North Atlantic. Memoirs Sears Found. Mar. Res. I, Pt. 3. New Haven, CT.

Walden, H.T. 1964. Familiar Freshwater Fishes of America. Harper and Row, New York. 324 pp.

Warren, M.L. Jr., B.M. Burr, S. J. Walsh, H.L. Bart Jr., R. C. Cashner, D.A. Etnier, B. J. Freeman, B.R. Kuhajda, R.L. Mayden, H. W. Robison, S.T. Ross, and W. C. Starnes. 2000. Diversity, distribution and conservation status of the native freshwater fishes of the southern United States. Fisheries 25(10):7-29.

Wiley, E.O. 1980. Lepisosteus osseus (Linnaeus), Longnose gar. pp. 49 in D.S. Lee et al. Atlas of North American Freshwater Fishes. N.C. State Mus. Nat. Hist., Raleigh, i-r+854 pp.

Winemiller, K.O., F.P. Gelwick, T. Bonner, S.C. Zeug, and C. Williams. 2004. Response of Oxbow Lake Biota to Hydrologic Exchanges with the Brazos River Channel. Report to the Texas Water Development Board. Texas Agricultural Experiment Station and Texas State University. 59 pp.

Yeager, B.L., and R.T. Bryant. 1983. Larvae of the longnose gar, Lepisosteus osseus, from the Little River in Tennessee. J. Tenn. Acad. Sci. 58:20-22.