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Home -> Kingdom Animalia -> Phylum Chordata -> Subphylum Vertebrata -> Class Actinopterygii -> Order Semionotiformes -> Family Lepisosteidae -> Species Lepisosteus platostomus

Lepisosteus platostomus
shortnose gar



2009/11/22 03:20:43.759 US/Eastern

By Mark Bradburn

Kingdom: Animalia
Phylum: Chordata
Subphylum: Vertebrata
Class: Actinopterygii
Order: Semionotiformes
Family: Lepisosteidae
Genus: Lepisosteus
Species: Lepisosteus platostomus

Geographic Range

The shortnosed gar is found in Mississippi River basin from south central Ohio, northern Indiana and Wisconsin to Montana and south to Alabama and Louisiana (Page and Burr, 1991). The species is also found in Lake Michigan drainage in Wisconsin. Shortnose gar presumably dispersed into Wisconsin from the Mississippi river via the Wisconsin and Fox rivers (Priegel, 1963). (Page and Burr, 1991; Priegel, 1963)

Biogeographic Regions:
nearctic (native ).

Habitat

Habitat of the shortnosed gar includes lakes, swamps, and the calm pools and backwaters of creeks and rivers. They are commonly found near vegetation and submerged logs. (Page and Burr, 1991)

These animals are found in the following types of habitat:
temperate .

Aquatic Biomes:
lakes and ponds; rivers and streams.

Wetlands: swamp .

Physical Description

Mass
1430 g (average)
(50.34 oz)
[External Source: AnAge]


Length
83 cm (high)
(32.68 in)


Gar species in North America are easily recognized by their long snouts, sharply toothed jaws, non-overlapping and diamond shaped ganoid scales, and posterior placement of dorsal and anal fins on the body. Specifically, the shortnose gar is characterized by a short (relative to other gars), broad snout. The upper jaw is longer then the rest of the head and contains only one row of teeth. The shortnose gar has olive or brown coloration with white on the ventral side and black spots on median fins. Paired fins usually lack spots (spots found only on individuals living in clear water). Juveniles have fairly broad dark brown stripes along back and side. (Page and Burr, 1991)

Some key physical features:
ectothermic ; bilateral symmetry .

Development

Shortnose gars may be smaller than 9-10 mm long when they hatch. Although capable of swimming, they use an adhesive structure to hang vertically by their snout from objects in the water, and they will commonly attach to surface film. After exhausting the yolk sac, the fry become more active and assume a horizontal attitude. The fry usually remain near area of egg deposition (Echelle and Riggs, 1972).

Reproduction

Breeding/spawning season
early to mid April until the end of May

Gars begin to spawn in early to mid April until the end of May (Eschelle and Burr, 1972). Shortnose gars spawn in shallow water among the grass and aquatic weeds and prefer grassy sloughs as spawning grounds. Their eggs are large, green, and poisonous to warm-blooded vertebrates, including humans (Eddy, 1974).

Key reproductive features:
iteroparous ; seasonal breeding ; sexual ; fertilization (external ); oviparous .

Shortnose gar do not care for their young.

Parental investment:
no parental involvement.

Behavior

Gars are commonly observed breaking the surface and gulping air to replace air in the lung, from which they add oxygen to the bloodstream (Cross and Collins, 1995; Pfleiger, 1997).

Key behaviors:
natatorial ; motile ; solitary .

Food Habits

Young of the year gars consume a variety of food items, ranging from tiny crustaceans to different life stages of insects and fish. The diet of young gars suggests that most feeding is surface oriented. Adult and young of the year gars feed more actively at night than during the day (Echelle and Riggs, 1972).

Hunting activity of gars can be described as stalking rather than active pursuit. Gars are typically opportunist, consuming the most available food. Shortnose gar consume more invertebrates than any other species of gar (Vokoun, 2000).

Gars are efficient ambush predators (Moyle and Cech, 1988). With its long jaws, gars lie in ambush and catch fish with a sideways strike (Bone, 1999).

Primary Diet:
carnivore (piscivore , insectivore , eats non-insect arthropods).

Animal Foods:
fish; insects; zooplankton .

Predation

Known predators

Due to gars bony composition and tough, interlocking ganiod scales, gars are nearly impervious to any forms of predation. Adult gars have no known predators except humans. (Iowa Dept of Natural Resources, 1987)

Ecosystem Roles

The shortnose gar are predators that can occupy the role of a scavenger, but often competes for food with common gamefishes like the northern pike, walleyes, and bass. However, they often thrive in waters not suitable for game fishes (Eddy, 1974).

Economic Importance for Humans: Negative

Fishermen have an aversion to the shortnose gar because of their competitive predatory habits and lack of value as a sport fish. Often fishermen attempt to capture them for purposes of removal. Fortunately for the shortnose gar, their slender shape and behavior make them difficult to capture in siene nets (Eddy, 1974).

Conservation Status

IUCN Red List: [link]:
Not Evaluated.

US Federal List: [link]:
No special status.

CITES: [link]:
No special status.

Since shortnose gar and other gar species compete with popular gamefishes, they are regarded as a nuisance to many sport fishermen. There are some gar fishing enthusiasts, but their popularity as a sport fish is low. Their perceived lack of value has prompted many actions to eliminate them from some aquatic areas. A related species, the alligator gar Atractosteus spatula, is under intense pressure in some parts of the southern United States (Eddy, 1974).

For More Information

Find Lepisosteus platostomus information at

Contributors

Mark Bradburn (author), University of Michigan.
William Fink (editor), University of Michigan.

References

Bone, Q., N. Marshall, J. Blaxter. 1999. Biology of Fishes. Cheltenham, UK: Stanley Thornes Ltd..

Cross, F., J. Collins. 1995. Fishes in Kansas. Lawrence, KS: University Press of Kansas.

Echelle, A., C. Riggs. 1972. Aspects of the early life history of gars *Lepisosteus* in Lake Texoma. Transactions of the American Fisheries Society, 101(1): 106-112.

Eddy, S., J. Underhill. 1974. Northern Fishes. Minneapolis, MN: University of Minnesota Press.

Iowa Dept of Natural Resources, 1987. "The Gar Family" (On-line). Accessed 03/02/2006 at http://www.iowadnr.com/fish/iafish/garfamil.html.

Moyle, P., J. Cech. 1988. Fishes: An Introduction to Ichthyology. Engelwood Cliffs, NJ: Prentice Hall.

Page, L., B. Burr. 1991. A Field Guide to Freshwater Fishes of North America North of Mexico. The Peterson Field Guide Series, vol 42. Boston, MA: Houghton Mifflin Company.

Pflieger, W. 1997. The fishes of Missouri. Jefferson City, MO: Missouri Department of Conservation.

Priegel, G. 1963. Dispersal of the Shortnose Gar, *Lepisosteus platostomus*, into the Great Lakes Drainage. Transactions of the American Fisheries Society, 92 (2): 178.

Volkoun, J. 2002. Shortnose gar (*Lepisoteus platostomus*) foraging on periodical cicadas (Magicicada spp.): territorial defense of profitable pool positions. American Midland Naturalist, 143: 261-265.

2009/11/22 03:20:44.943 US/Eastern

To cite this page: Bradburn, M. 2003. "Lepisosteus platostomus" (On-line), Animal Diversity Web. Accessed November 23, 2009 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Lepisosteus_platostomus.html.

Disclaimer: The Animal Diversity Web is an educational resource written largely by and for college students. ADW doesn't cover all species in the world, nor does it include all the latest scientific information about organisms we describe. Though we edit our accounts for accuracy, we cannot guarantee all information in those accounts. While ADW staff and contributors provide references to books and websites that we believe are reputable, we cannot necessarily endorse the contents of references beyond our control.

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