Evaluation of striped bass, Morone saxatilis, condition in coastal North Carolina using physiological and condition indices / by David E. Gentry.
| Author/creator | Gentry, David E. author. |
| Other author | Rulifson, Roger A. (Roger Allen), 1951- degree supervisor. |
| Other author | East Carolina University. Department of Biology. |
| Format | Theses and dissertations |
| Production | 2006. |
| Description | viii, 104 leaves : illustrations (some color), maps (some color) ; 28 cm |
| Supplemental Content | Access via ScholarShip |
| Subjects |
| Summary | Over the past several years, anecdotal evidence has suggested a decline in the condition of the striped bass (Morone saxatilis) from the Albemarle Sound-Roanoke River (A-R) population. Striped bass were sampled from January-December 2005 to determine if the A-R population is experiencing a decreased overall condition from overpopulation and declining forage. Several condition and physiological indices were measured including relative weight (Wr), liver-somatic index (LSI), and visceral fat index (VFl). By monitoring the A-R population through its yearly migration into the river, and back into the sound, the physiological changes in the fish were observed across the seasons. The gonadosomatic index (GSI) was calculated to correlate the energy shift from reproduction to somatic storage, and stomach content was recorded. Samples were taken from the Tar-Pamlico watershed for comparison, and condition was shown to be very similar to that of the A-R population. Results showed that the condition of striped bass is highly variable throughout the year, with the highest condition values in the winter and the lowest in the summer. The condition was highly correlated to both the LSI and VFI indices and was inversely proportional to water temperature, suggesting the effect of water quality on the physiology of striped bass. Liver tissue analysis confirmed the LSI data with mean winter hepatocyte size approximately 2.8 times than in the summer tissue samples. Stomach contents consisted primarily of Atlantic menhaden (Brevoortia tyrannus) although other species were present in small quantities. Relative weight values for the summer of 2005 were shown to be lower than for a similar study during the same months in 1993. NCDMF data from the winter and spring months from 1995-2003 indicate variable condition from year to year, but did not show a consistent pattern in striped bass condition. Long term comparisons with data from 1970 and 1971, another high abundance period, suggest a significant decline in condition when compared with 2005. |
| General note | Presented to the faculty of the Department of Biology. |
| General note | Advisor: Roger A. Rulifson |
| Dissertation note | M.S. East Carolina University 2006 |
| Bibliography note | Includes bibliographical references (leaves 82-87). |
| Genre/form | dissertations. |
| Genre/form | Academic theses. |
| Genre/form | Academic theses. |
| Genre/form | Thèses et écrits académiques. |
Availability
| Library | Location | Call Number | Status | Item Actions |
|---|---|---|---|---|
| Joyner | University Archives | ASK AT SPECIAL COLLECTIONS DESK | ✔ Available | Request Material |
| Electronic Resources | ✔ Available |