Specific gravity and vertical distribution of sprat eggs in the Baltic Sea

$48.00 plus tax (Refund Policy)

Download / Buy Article:

Abstract:

During peak spawning of sprat Sprattus sprattus in the Baltic Sea in May–June egg specific gravity averaged ±s.d. 1·00858 ± 0·00116 g cm−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 (r2 = 0·71). 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.

Keywords: Baltic Sea; Sprattus sprattus; egg specific gravity; egg survival; reproductive success; vertical distribution

Document Type: Regular Paper

DOI: http://dx.doi.org/10.1046/j.1095-8649.2003.00139.x

Affiliations: 1: Ar Research Station, Gotland University College, SE-620 35 Fårösund, Sweden and 2: Institute of Marine Research, University of Kiel, D-241 05 Kiel, Germany

Publication date: August 1, 2003

Related content

Tools

Favourites

Share Content

Access Key

Free Content
Free content
New Content
New content
Open Access Content
Open access content
Subscribed Content
Subscribed content
Free Trial Content
Free trial content
Cookie Policy
X
Cookie Policy
ingentaconnect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more