Growth, Spawning Preparedness, and Diet ofCycleptus meridionalis(Catostomidae)

Abstract

Cycleptus meridionalis is a new species recently distinguished from blue sucker C. elongatus. It occurs in large rivers draining to the northern Gulf of Mexico chiefly through Alabama and Mississippi. Collections over a 12‐month period from the Pearl and Pascagoula rivers, Mississippi, were taken to document the new species' life history characteristics. Female C. meridionalis had significantly greater wet weight (WW, kg) per given total length (TL, mm) (WW = 4.228−13 TL4.588) than males (WW = 2.000−9 TL3.237). Aged opercular bones indicated that one annulus formed during September–October at the beginning of the reproductive season. Fish ages in the sample ranged from 6 to 31 years for females and from 4 to 33 years for males. Longevity of C. meridionalis is markedly greater than previous scale aging of C. elongatus had suggested. Male C. meridionalis as small as 327 mm TL (age 4) and females as small as 444 mm TL (age 11) had visibly developed gonads; mean gonadosomatic index was elevated in both sexes between October and March and declined by early April. Spawning began in February to early March when the temperature exceeded 13–14°C. The sex ratio was not different from 1:1 (P > 0.05). Cycleptus meridionalis foraged on aquatic insect larval stages; trichopteran larvae and pupae, chironomid larvae and pupae, and coleopteran larvae were the most common prey items regardless of sex, size, or river. These life history characteristics and food habits are similar to those reported for C. elongatus in the Mississippi River drainage. Our observations indicate that C. meridionalis is viable in both rivers sampled but may be influenced by future river modification as has happened with C. elongatus, which is threatened or endangered over much of its range.

Blue sucker stock characteristics in the upper Yazoo River basin, Mississippi, USA

“…However, Beamish & McFarland (1987), and Peterson, Nicholson, Snyder & Fulling (1999), showed that scales underage catostomid fishes, and that the use of opercular bones provides more accurate age estimates. Using opercular bones, Peterson et al . (1999) aged blue suckers ( C. meridionalis ) in the Pearl and Pascagoula rivers, Mississippi at 4–33 years.…”

Historic and recent age structure and growth of endangered Lost River and shortnose suckers in Upper Klamath Lake, Oregon

“…Previous attempts at ageing these species included the use of scales and opercular bones (Scoppettone 1988); however, scales are notorious for underestimating age in long-lived species, and ages from opercula may also underestimate true age. Researchers (Scoppettone 1988;Peterson et al 1999) have described the presence of hidden annuli on catostomid opercular bones due to fenestrated reinforcement bone immediately ventral to the hyomandibular socket, the number of which was a function of the age and shape of the opercle. In contrast, lapilli for these species are easily prepared for reading, growth marks are annular, and checks are relatively easy to distinguish from true annuli.…”

Distribution and growth of blue sucker in a Great Plains river, USA

“…Other studies have also collected relatively few small fish using electric fishing (Rupprecht & Jahn 1980; Moss et al. 1983; Peterson, Nicholson, Snyder & Fulling 1999; Hand & Jackson 2003; Morey & Berry 2003; Vokoun et al. 2003).…”