Egg size and larval size among teleosts: implications to survival potential

TitelEgg size and larval size among teleosts: implications to survival potential
MedientypJournal Article
Jahr der Veröffentlichung1986
AutorenBagarinao, T. U., and T. E. Chua
JournalProceedings of the First Asian Fisheries Forum
Veröffentlichungsdatum05/1986
Zusammenfassung

A survey of the early life history characteristics of 135 teleost fishes from freshwater, marine, tropical, temperate and boreal habitats show the influence of egg size and larval size on survival potential. Marine species have smaller eggs and larvae than freshwater species at similar temperatures. Coldwater species tend to have larger eggs and larvae than warm water species. Egg diameters are positively correlated with larval lengths (Lh) and weights at hatching. The times from fertilization to onset of feeding (tf), to yolk and oil resorption (ty) and to irreversible starvation (ts), increase linearly with Lh and decrease exponentially with temperature. Both tf and ts are positive linear functions of ty. Thus, larger larvae with much yolk that lasts for a relatively longer period feed later and if not fed, will starve later than small larvae with little yolk. Larger larvae will thus have the advantage under conditions of limited or variable food supply. Moreover, large larvae tend to have large mouths and are thus capable of ingesting large high-calorie prey. They also tend to have higher swimming speeds and greater potential to encounter food and avoid predators. There is no definite relation between growth rates and Lh, but tropical species with small eggs and larvae tend to have high growth rates. Survival potential has implications in the recruitment to natural stocks and in seed production in hatcheries.

URLhttp://hdl.handle.net/10862/257



Und denn, man muß das Wahre immer wiederholen, weil auch der Irrtum um uns her immer wieder gepredigt wird, und zwar nicht von Einzelnen, sondern von der Masse. In Zeitungen und Enzyklopädien, auf Schulen und Universitäten, überall ist der Irrtum oben auf, und es ist ihm wohl und behaglich, im Gefühl der Majorität, die auf seiner Seite ist. -Oft lehrt man auch Wahrheit und Irrtum zugleich und hält sich an letzteren. {Johann Wolfgang von Goethe}