TN00219 SPOTTED BASS MICROPTERUS PUNCTULATUS
Physical description: The adults are blotched, speckled and usually stripe-sided with a low first dorsal fin. The adults are usually from 250-380 mm SL. The body is somewhat elongate to slightly stocky, and moderately compressed. The dorsal profile of the head is nearly straight to moderately convex. The mouth is terminal and large with the posterior end of the maxilla usually even with the posterior eye rim. The dorsal fin is not deeply emarginate at the junction of the spinous and soft portions. The caudal fin is moderately forked, and the pectoral is rounded. There is a small patch of tiny teeth present on the tounge. There are (55)60-68(72) lateral line scales with (7)8-9 scales above the lateral line and (14)15-17(18) below the lateral line. There are (22)23-27 circumpeduncle scales, 9-10(11) dorsal spines, 11-13(14) dorsal rays, (2)3(4) anal spines, (9)10(11) anal rays and (14)15-16(17) pectoral rays. The midlateral blotches are olive-brown to olive-black, with the ground shade of the dorsum pale to dark olive or green. The dorsolateral mottling is dark olive. The dorsolateral scale centers are whitish forming long- itudinal rows. The ground color of the lower sides and venter is whitish and the ventrolateral spots are dark olive-black. The cheek bars are dark olive and the opercular spot is black. The spinous dorsal fin is pale olive and the soft dorsal fin is pale olive with a basal mottling of olive-brown. The caudal fin is olive with a yellow wash. The anal and pelvic are whitish and the pectoral is pale *4205*. Reproduction: Maturity for both sexes can occur in year I in warm water reservoirs, but less than 50% are mature. All year II bass can be mature *2325*, although some are not mature until 4 years of age *4205*. Maturity relates to age and length, and the larger fish mature quicker *1496,2615*. The male and female sex ratio tends to be equal *2615*. All females can spawn by age IV *2324*. Fecundity increases with the size of the female, ranging from 3806 ova/female to 30,586 ova/female *4205*. Spawning habitat require- ments are more specific for spotted bass than largemouth bass *2615*. The beginning of the spawn dependent on water temperatures, and is initiated in Virginia at temperatures from 15-19 degrees C, probably from late April to mid-May in Virginia *4205*. Most activity is in the afternoon, but ranges from mid-morning to dusk *2311*. The number of eggs deposited ranges from 763-18,995 and the length of time to hatch is dependent on water temperature and lasts from 2 days at 70 degrees F, to 5 days at 58 degrees F *2311,2324*. The young disperse approximately 4-8 days after hatching *2312*. Factors influencing reproduction and survival of eggs are: (1) water level fluctua- tions, (2) wind and wave action, (3) water quality, (4) aquatiac and terres- trial cover, (5) air and water temperature, (6) invertebrate and fish preda- tion, and (7) human activity *1272*. Behavior: This species prefers nest sites near cover *2324*. It nests at depths of 9 inches to 4 feet in reservoirs, and 13 inches to 29 inches in streams *2616*. Males build nests by the vigorous sweeping of the substrate with the caudal fin to create a circular depression *2324*. The diameter of the nest ranges from 15-36 inches *2616*. Courtship behavior entails male and female circling and male biting at the opercle vent, which takes from 20 minutes to 1 hour, followed by egg deposition *2312*. The males guard the nest and fan the eggs *1647*. Fry form schools which are guarded until they reach approximately 1.2 inches long when the schools disperse *2324*. A home range is exhibited by both sexes, and they have a very restricted home range during spawning *1314,2310*. Origin: This species is native in the Big Sandy and Tennessee drainages *4205*. Limiting factors: Parasites of this species include flukes, grubs, bass tapeworm, spiny headed worms, roundworms, leeaches, fish lice, and anchorworms *1290*. Heavy infestations can cause sterility and death *1290*. The life stages are as follows: (1) egg = stage from ova fertilization to hatching (embryo, fluids, and shell), (2) larva (fry) = hatching to dispersal from nest (yolk sac absorption and pigmentation formation), (3) fingerling (young of year) = dispersal from nest to adult, first season (or first year) of life, and (4) adult = post-fingerling state (after 1st year, may or may not be reproductive) *1155*. Population parameters: Growth is generally slower than for largemouth bass and equivalent to smallmouth. Growth is faster in reservoirs than in streams and annulus formation on the scales occurs earlier on younger fish *2309,1647*. The length-weight relationships for this species is equivalent to those of the largemouth and smallmouth *2323,2615*. Elements to model a fish (bass) population in a reservoir include: (1) need minimum of 25 lbs/acre of predator (bass), (2) 75 lbs/a plankton feeders (e.g., shad), (3) 100 lbs/acre of bottom feeders (e.g., catfish) with the production of these 3 factors controlled by: the fertility of the water, climate, water level fluctuations, shape of basin, and substrate composition *1271*. Biological factors which influeance early life stages include: (1) the size of the spawning population, (2) predation and cannibalism, (3) disease and fungi--important in hatcheries, not in wild, and (4) starvation--important in hatcheries, not evident in wild populations *1155*. Factors to estimate standing crop of bass include: (1) water depth and area of watershed and area underwater, (2) fertility of water and watershed (3) species composition of system, (4) population estimate, (5) average seasonal water temperature and (6) the length of the growing season *1292*. Aquatic/terrestrial associations: This species is associated with Micropterus coosae (red eye), M. salmoides (largemouth bass) and M. dolomieui (smallmouth bass) *2311,2322*. This species will often occupy habitats different from largemouth or smallmouth that live in the same stream, with this species preferring more current then largemouth and less than smallmouth *2311*. POPULATION PARAMETERS: ANNUAL ANGLER EXPLOITATION RATE IN CENTER HILL RESERVOIR ESTIMATED AT APPROXIMATELY 30% *TN5352*, TOTAL ANNUAL MORTALITY RATES IN CENTER HILL RESERVOIR ESTIMATED AT 71-85% *TN5353* *TN5354* GROWTH RATES: IN NEW RIVER, TENN., TOTAL LENGTH AT EACH ANNULUS WAS 72, 137, 183, 230, AND 245 MM *TN5351*, IN CENTER HILL RESERVOIR, LENGTH AT EACH ANNULUS WAS 170, 264, 353, 406, AND 422 MM *TN5353*, IN PICKWICK RESERVOIR LENGTHS AT EACH ANNULUS WERE 118, 199, 262, 306, 354, AND 361 MM *TN5355*
| Life History |
References for Life History Codes
816, 2615, 2324, 2616, 2612, 2321, 2311, 2312, 1647, 2617, 2309, 2323, 1290, 1314, 2310, 835, 1272, 1271, 1155, 1292, 4205
Comments on Life History Codes