Specific gravity and vertical distribution of sprat eggs in the Baltic Sea
2003 (English)In: Journal of Fish Biology, ISSN 0022-1112, Vol. 63, no 2, 280-299 p.Article in journal (Refereed) Published
During peak spawning of sprat Sprattus sprattus in the Baltic Sea in May-June egg specific gravity averaged plus or minus s.d. 1 times 00858 plus or minus 0 times 00116 g cm super(-3) but was significantly higher in the beginning and significantly lower towards the end of the spawning season. A close relationship was found between egg diameter and egg specific gravity (r super(2) = 0 times 71). This relationship, however, changed during the spawning season indicating that some other factor was involved causing the decrease in specific gravity during the spawning period. The vertical egg distribution changed during the spawning season: eggs were distributed mainly in the deep layers early in the season, occurred in and above the permanent halocline during peak spawning, and above the halocline towards the end of the spawning season. Consequently, poor oxygen conditions in the deep layers and low temperatures in layers between the halocline and the developing thermocline may affect egg development. Thus, opportunities for egg development vary over the spawning season and among spawning areas, and depending on frequency of saline water inflows into the Baltic Sea and severity of winters, between years.
Place, publisher, year, edition, pages
London: Academic Press , 2003. Vol. 63, no 2, 280-299 p.
Baltic Sea, egg specific gravity, egg survival, reproductive success, Sprattus sprattus, vertical distribution
Research subject Biology
IdentifiersURN: urn:nbn:se:hgo:diva-174DOI: 10.1046/j.1095-8649.2003.00139.xOAI: oai:DiVA.org:hgo-174DiVA: diva2:276029