TN00014 BOWFIN AMIA CALVA
Physical description: This is a stout-bodied, cylindrical fish with a long dorsal fin and a bony plate on the underside of the lower jaw. The adults are usually ca400-600 mm TL, and the body is elongate, and slightly compressed posteriorly. The heqad and eyes are moderate, the anterior nare tubal and the mouth subterminal. The jaws bear small canine and peglike teeth and there is a large gular plate present. The dorsal fin is long and uniform in height. The caudal is abbreviate, heterocercal, round and scaled at the base. The lower fins are small and round. The body is fully scaled and the scales are primitive cycloid, with parallel ridges. The lateral line is complete and the anterior scales have bifid pores. Total scales number 62-70. There are 42-53 dorsal rays, 25-28 caudal rays, 9-12 anal rays, 16-18 pectoral rays and 7 pelvic rays. The head is black and the upper side tan-olive with a rusty tinge. Reticulation is dark olive, and the head bars are are dark olive. The dorsal and caudal fins are pale olive with dark olive mottling. The ocellus is dark olive, ringed with red, and the lower fins are pale olive. Reproductive males intensify and the fins bercome bright green the back bronze and the head spots, other patterns and caudal spot become further black *4205*. Reproduction: In Missouri, they spawn in early April to May or early June *6232*. In Kansas, they spawn in the spring *2980*, and in Wisconsin, in late April or early May *5989*. A female may spawn in the nests of 2 or more males, and the nests may be located on the bottom of fibrous roots *6232*. Incubation takes from 8-10 days *5989*, and at hatching, the larvae have an adhesize disc on the snout, and remain in the nest approximately 9 days, until the yolk sac is absorbed *2980*. In Missouri, half of the males were mature at age I, and all at age II. 35% of age II females were mature and all at age III were mature *6232*. In Missouri, the sex ratio is equal during the 1st 2 years, and after that, females usually predominate. The sex ratio for a sample showed 68 males to 100 females *6232*. They usually spawn at night, and in deeper water during the day. Behavior: They are randomly dispersed, but school during the fry stage *842*. Adults usually remain in deeper water or under cover during the day *6266*. In a Missouri study, juveniles in the lab ate more between 5 and 10 p.m. *6199*. They may surface periodically to renew their air supply in the swim bladder, which functions as a lung *6266,5991*. Periodicity is late spring, early summer, and late summer *788*. The male defends the nesting territory, and guards the nest and young *842*. They often feed at night, stalking prey *788,5989,6266*. Origin: The origin of this species is native, transplanted *835,1115*. Limiting factors: Parasites include fish lice and cestodes. Diseases include tail and fin rot *6232*. Predators of the young include painted and snapping turtles, bullfrogs, and adult bowfin *6199*. Population parameters: Most adults are from 15-27 long and weigh from 1-5 pounds *6266*. In Missouri, the greatest gain in length was in April *6232*. Fish paired in aquaria exhibited faster growth in length and weight than single fish. Yearling bowfin in aquaria increased an average of .43 mm/day in total length and 1.11g/day in weight *6199*. In Missouri, length-weight ranges were 3.6-33.2, and weight ranges were .35-12.75 pounds. The length-weight relationship is (log w -4.931 + 2.956 log l) *6232*. The life span is 10 years under natural conditions, and in captivity they have lived up to 30 years *6266*. The young the leave nest in a swarm, guarded by the male *2212*. In Missouri, 75% of 1 captured swarm contained 11,747 young. The young leave the swarm when they are approximately 2 ? long *6232*. In Missouri, the total mortality rate in the first summer of life is 98% *6199*. DISTINGUISHED BY PRESENCE OF GULAR PLATE BETWEEN HALVES OF LOWER JAW, ROUNDED CAUDAL FIN, AND LONG, LOW DORSAL FIN *TN5058*. MALES CONSTRUCT NESTS REMOVING VEGETATION BY BITING AND RUBBING SILT IS FANNED AWAY *TN5071*. EGGS HATCH IN 8-10 DAYS YOUNG BECOME ATTACHED TO NEST BY AN ADHESIVE ORGAN ON THEIR NOSE AND REMAIN THERE 7-9 DAYS *TN5175*. SEXUAL MATURITY REACHED AT 2 OR 3 YEARS OF AGE 10 YEARS IS ABOUT MAXIMUM LIFE SPAN REACHED UNDER NATURAL CONDITIONS *TN5071*. MATURE MALES HAVE BLACK CAUDAL SPOT, A DEFLECTIVE MARK FEMALES ARE GENERALLY LARGER THAN MALES *TN5076*. HAS BEEN KNOWN TO AESTIVATE *TN5072*.
| Life History |
References for Life History Codes
835, 1115, 788, 842, 6232, 2980, 2989, 2212, 6266, 6199, 4205, TN5058, TN5071, TN5175, TN5076, TN5072
Comments on Life History Codes