TN00198 LONGNOSE GAR LEPISOSTEUS OSSEUS
Physical description: This is an elongate fish with bony scales and a beaklike snout bearing many sharp teeth. The adults are usually from 670-1150 mm TL. The trunk is very elongate, oval or quadrate in cross section and fully covered with interlocking rhomboid scales. The head is slender and there are many rugose cranial bones exposed. The eye is moderate and the jaws very attenuate, armed with needlelike canine teeth. The upper jaw slightly occludes the lower and nares are distal on the upper jaw. The pseudobranchae are well developed and the gill arches have patches of rasplike teeth. The dorsal and anal fins are far back on the body. The caudal fin is abbreviate hetercercal, round, and dorsal with the leading edge with a splint like fulcra. The pelvic fin is small and ventral, well in advance of the vent. The pectoral is small and ventral. The lateral line is complete and the cephalic lateralis moderately developed. The young have a free upper caudal filament, and a fleshy enclosure of the distal notochord, usually lost between 250-280 mm TL. There are 57-63 lateral line scales, 47-55 predorsal scales and 31-35 transverse scales between the dorsal and pelvic origins. There are 6-9 dorsal rays, 11-14 caudal rays, 8-10 anal rays, 6 pelvic rays and 10-13 pectoral rays. There are 14-31 short, stubby gill rakers. The juvenile and the adult are pale olive or green above, grading to white or silver-white on the venter. The side has remnants af a lateral stripe in the form of dark blotches or smaller marks. The median fins are cream with large black spots or marks. In the young the dark markings are brown to brow-black, the dorsum pale brown and the lower side stripe cream *4205*. Reproduction: This species spawns during the spring in the lower reaches of medium sized tributaries and lakes. In southwestern Virginia, spawning occurs between mid-May and eatrly June, and lasts for about 2 weeks. Spawning occured near the bank in a slow run over boulder and bedrock at a depth of ca 1-1.5 meters. The adhesive eggs are scattered singly or in small clusters over the bottom. The males nudged the female with the snout and the gametes were released while in a head-down position with the snout close to the bottom. Communal spawning has been observed with up to 15 males pursuing a single female *4205*. Behavior: Larval longnose gar begin feeding at ca 20 mm TL, and almost immediately the piscivorous habit is consummated. Larvae, young and adults seize fish laterally. During larval stages, they feed more often on micro- crustaceans and immature insects although a wide variety of fish dominate the juvenile and adult diets. They also consume insects, crayfish, crabs, frogs and even a shrew has been noted. During warm periods gar will frequently gulp air. They are associated with weedy areas and cover in pools and backwaters and will often quietly suspend just below the surface *4205*. Limiting factors: The highest salinity record for this species is 31 ppt *4205*. Population parameters: Males mature at age 3 or 4 and females at age 6. First-year growth averages as much as 3.2 mm per day. Fecundity ranges from 6,200 to 77,150 eggs *4205*. Aquatic/terrestrial associations: The eggs of this species are said to be poisonous to humans. Nocomis micropogon have been observed eating gar eggs. Gar will spawn on smallmouth bass nests in Lake Erie *4205*. REPRODUCTION: WHEN SPAWNING ADULTS GATHER IN LARGE NUMBERS OVER GRAVELLY STRETCHES OF SHALLOW RIFFLES NO NEST IS PREPARED BUT THE GRAVEL IS CLEANED BY THE SPAWNING ACTIVITIES *TN5071* AS MANY AS 15 MALES APPROACH A FEMALE IF SHE IS READY TO SPAWN, SHE LEADS THEM IN AN ELLIPTICAL PATH (APPARENTLY RELATED TO THE SHAPE OF THE SPAWNING GROUND) FOR UP TO 15 MINUTES BEFORE SPAWNING OCCURS OVER THE SPAWNING BED THE MALES NUDGE THE FEMALE, FREQUENTLY SURFACING AND GULPING AIR THE SPAWNING GROUP THEN POSITIONS ITSELF AT ONE PLACE WITH HEADS DOWN AND SNOUTS VERY CLOSE TO OR TOUCHING THE BOTTOM MALES CONTINUE TO NUDGE THE FEMALE A RAPID, VIOLENT QUIVERING OF SPAWNERS FOLLOWS AS EGGS AND SPERM ARE RELEASED *TN5176* SPAWNING BY ONE FEMALE AND HER ATTENDING MALES STIMULATES SIMILAR ACTIVITY BY OTHERS AND FREQUENTLY ALL THE INDIVIDUALS IN THE VICINITY GATHER IN A COMPACT GROUP AND VIBRATE REPIDLY OFTEN THEY BREAK THE SURFACE, CREATING LOUD SPLASHING SOUNDS THE FEMALE DOES NOT DEPOSIT ALL HER EGGS AT ONCE, AND THE SPAWNING ACT IS REPEATED AT WIDELY SPACED AND IRREGULAR INTERVALS *TN5071* EGGS ARE GREEN AND HATCH IN 3-9 DAYS DEPENDING ON TEMPERATURE (6 DAYS AT 20 DEGREES C) *TN5176* BEHAVIOR: FRY, 9-10 MM LONG UPON HATCHING, ARE CAPABLE AT 18-20 MM OF RESTING MOTIONLESS IN A HORIZONTAL POSITION AT ANY DEPTH AT ABOUT THIS TIME IT TAKES ITS FIRST AERIAL BREATH, BECOMES MORE ACTIVE, AND BEGINS TO FEED THE FRY DISPERSE AFTER ABSORPTION OF THE YOLK SAC LONGNOSE GAR FEED MORE ACTIVELY AT NIGHT MUCH OF THE FEEDING IS SURFACE ORIENTED IT IS ADEPT AT STALKING A FISH VICTIM BY SWIMMING OFF TO ONE SIDE OF IT, MOVING ALONG IN THE WATER LIKE A STICK DRIFTING WITH THE SURFACE CURRENT IT SUDDENLY FLIPS ITS LONG BILL TO THE SIDE AND CATCHES ITS PREY ACROSS THE BODY BY A SERIER OF THRUSTS, IT THEN TURNS THE VICTIM SO THAT IT CAN BE SWALLOWED HEAD FIRSE DURING DAYLIGHT IT SPENDS MUCH TIME RESTING MOTIONLESSLY CLOSE TO SUBMERGED OR OVERHANGING OBJECTS NEAR SHORE ADULTS TEND TO BASK NEAR THE SURFACT ON WARM DAYS OR NIGHTS AND MAY BE SEEN FLOATING LIKE STICKS *TN5176*
| Life History |
References for Life History Codes
4205, 1252, 1260, 1229, 1251, 1249, 1253, 1250, 2406, 1254, 1261, 1256, 1270, 1248, 1258, 1262, TN5071, TN5176
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