|The buoyancy and vertical distribution of eggs of sprat (Sprattus sprattus) and pilchard (Sardina pilchardus)|
Coombs, S.H.; Fosh, C.A.; Keen, M.A. (1985). The buoyancy and vertical distribution of eggs of sprat (Sprattus sprattus) and pilchard (Sardina pilchardus). J. Mar. Biol. Ass. U.K. 65(2): 461-474
In: Journal of the Marine Biological Association of the United Kingdom. Cambridge University Press/Marine Biological Association of the United Kingdom: Cambridge. ISSN 0025-3154, more
Buoyancy; Fish eggs; Vertical distribution; Pisces [WoRMS]; Clupeidae Cuvier, 1816 [WoRMS]; Sardina pilchardus (Walbaum, 1792) [WoRMS]; Sprattus sprattus (Linnaeus, 1758) [WoRMS]; Marine
|Authors|| || Top |
- Coombs, S.H.
- Fosh, C.A.
- Keen, M.A.
Eggs of sprat (Sprattus sprattus (L.)) and pilchard (Sardina pilchardus (Walbaum)) were sampled locally off Plymouth, U.K. Sprat eggs were typically less dense than local sea water at the mid-stages of development and increased in density to reach near neutral buoyancy by hatching. Both summer and autumn-spawned pilchard eggs had near constant buoyancy for the first three-quarters of development but summer eggs were less positively buoyant than those spawned in the autumn. Both groups of pilchard eggs increased in density in the later stages of development so that by hatching a significant proportion were more dense than local sea water. The density of pilchard eggs was altered by the salinity of the medium; this influence is discussed in the relation to its potential effect on experimental procedures used to determine egg density. It was concluded that mixing effects dominated the vertical distribution of the eggs.