|The reproductive cycle of the sponge Halichondria panicea Pallas (1766) and its relationship to temperature and salinity|
|Witte, U.; Barthel, D.; Tendal, O. (1994). The reproductive cycle of the sponge Halichondria panicea Pallas (1766) and its relationship to temperature and salinity. J. Exp. Mar. Biol. Ecol. 183(1): 41-52|
|In: Journal of Experimental Marine Biology and Ecology. Elsevier: Amsterdam. ISSN 0022-0981, more|
Marine invertebrates; Oogenesis; Reproductive cycle; Salinity effects; Seasonal variations; Sex ratio; Temperature effects; Halichondria panicea (Pallas, 1766) [WoRMS]; Marine; Brackish water
|Authors|| || Top |
- Witte, U.
- Barthel, D.
- Tendal, O., more
The reproductive cycle of the sponge Halichondria panicea was investigated at Boknis Eck in the Western Kiel Bight over 2 yr, and over 1 yr on the island Helgoland in the North Sea and was compared with material collected earlier at Tjaernoe at the Swedish west coast. Temperature and salinity were monitored at the different stations in order to determine whether different hydrographic conditions could be linked to differences in seasonal patterns of the reproductive cycle. The results showed H. panicea to be gonochoristic at all stations. The ratio of males to females varied between populations and years, but females predominated consistently. Comparison of the reproductive cycle in the years 1987 and 1989 at the brackish-water station Boknis Eck shows that high ambient winter and spring temperatures in 1989 resulted in a shorter period of oogenesis and earlier larval release, as compared to the year 1987. The reproductive cycle of the sponges at the fully marine station at Helgoland in 1989 and the brackish-water station at Tjaernoe in 1978 under temperature and salinity conditions similar to those at Boknis Eck in 1989 showed the same seasonal pattern. We conclude that the lower salinities found at both Boknis Eck and Tjaernoe do not cause a delay or slow-down of reproduction at these stations as compared to Helgoland. Under favourable temperature conditions, oogenesis was highly synchronous within the different populations, while it was more spread over time under the low ambient water temperatures at Boknis Eck in 1987.