Student Research Projects
Use of Otoliths to age Gizzard Shad (Dorosoma cepedianum) from 3 Central Florida Lakes
In many species of fishes, otoliths (ear stones) are used to accurately determine fish age, because of the formation of annual layers. We are using this technique to age fish from 3 central Florida lakes (Apopka, Griffin and Newnans) as a part of a project documenting the effects of a large scale fish removal. Otoliths are dissected out and placed in a glyceryn-ethanol mix. Fish ages are determined from annular rings of whole otoliths or from cross sections of larger otoliths. Data will be used to examine population age structure, annual growth rates and the degree to which growth rates are altered by a population reduction. Results will also be compared with model outputs simulating population dynamics in response to simulated population reductions in these systems.
St. John's River Water Management District