comparison of fish ageing techniques: using scales and otoliths from largemouth bass in old city...
TRANSCRIPT
Comparison of Fish Ageing Techniques: Using Scales and Otoliths from Largemouth
Bass in Old City Lake.
Joey Dyer
Undergraduate, Department of Biology
Tennessee Technological University
Cookeville, TN 38505
Project Summary
• The objective of this study is to compare the two most common aging techniques of bass.
• The techniques are using the scale and otolith method.
• The scale method is the easiest of the two but not as precise as the otolith method.
• The problem with using the otolith method is that the fish is sacrificed in the process.
Scale Method
Otolith Method
Introduction
• The use of hard parts is based on the appearance of annuli rings (Kruse et la 1995).
• Historically, scales have been most often used (Weisberg 1993b).
• Otolith samples are more accurate ( Eveson et la 2004).
Hypothesis Statement
• Although the fish will be sacrificed, the otolith sample will give a better estimate of the fishes age, due to the regeneration of scales that have been lost prior to capture.
Methods and Materials
• 17 bass were collected from Old City Lake by electro-fishing
• Scale samples and otoliths were removed• Annuli rings on both scales and otoliths were
recorded• Rings pressed and counted under a projector for
scales• Rings counted under a microscope for otoliths
Bass
Age b
y Oto
lith In
Yea
rs
Age b
y Sca
le M
ethod
In Y
ears
123456789
101112131415161718
Data Form
Expected Results
• Otolith samples will be more precise but the fish will have to be sacrificed in the process
• The scale method will give a good estimate of the fishes age
Project Timeline
Research Topic/Title (Research title was developed) Week(s) 1-2
• Library Literature Search (Searched for relevant literature) Week(s) 2-4
• Scientific Method Objective/Hypothesis (Developed matrix, objective and hypothesis) Week(s) 3-6
• Research Proposal Key Words (determined good keywords) Week(s) 4-6
• Web Page (began development of the webpage) Week(s) 5-9
• Data Form / Format / Midterm Outline (developed a data form, learned the format for the research proposal outline and drafted the outline) Week(s) 5-6
• Research (compiled and analyzed data, completed research) Week 5-6
• Abstract (began writing the abstract, summary and conclusion Week 5-6
• Midterm (gave research proposal presentation) Week 7
• Spring Break Week 8
• Platform presentation (started developing presentation) Week 9
• Developed a resume and Ethics statement Week 10
• Designed poster and had the manuscript evaluated. Week11
Wrote a research progress report Week 12
Rewrote the research proposal as a research proposal application Week 13
Time for the platform presentation Week 14
Literature Cited• Caldow, C., G. M. Wellington. 2003. Patterns of annual increment formation in Otoliths of
pomacentrids in the tropical western Atlantic: Implications for population age structure examination. Marine Ecology Progress Series 265: 185-195.
• Campana, S. E., M. C. Annand, and J. I. McMillan. 1995. Graphical and statistical methods for
determining the consistency of age determinations. Transactions of the American Fisheries Society 124: 131-138.
• Eckmayer, W. J., J. F. Margraf. 2001. Ageing early age – 0 white bass (Morone chrysops) by
daily otolith increment analysis. Journal of Freshwater Ecology 16: 653-654. • Eveson, J. P., G. M. Laslett, and T. Polacheck. 2004. An integrated model for growth
incorporating tag-recapture, length frequency, and direct aging data. Canadian Journal of Fisheries and Aquatic Science 61: 292-306.
• Kruse, C. G., C. S. Guy, and D. W. Willis. 1993. Comparison of otolith and scale age
characteristics for black crappies collected from South Dakota waters. North American Journal of Fisheries Management 13: 856-858.
• Weisberg, S. 1993b. Using hard-part increment data to estimate age and environmental effects.
Canadian Journal of fisheries and Aquatic Sciences 50: 1229-1237.
Budget
• Salaries & Wages 10,000• First Year• Professional• Technician• Secretarial• Graduate Student• Student Hourl• Subtotal• Benefits• Travel• Non-Expendables 2,000• Expendables 1,000• Computer • Supplies & Expenses 2,000• Copying & Telephon• Tuition & Fees• Subtotal 15,000• Total Direct Costs• Indirect Costs• Total Costs 15,000