Journalartikel

Jahr der Veröffentlichung: 1985

Seiten: 165-186

Zeitschrift: Helgoländer Meeresuntersuchungen

Bandnummer: 39

Heftnummer: 2

ISSN: 0174-3597

Open Access Status: Bronze

DOI Link: https://doi.org/10.1007/BF01997448

Verlag: Biologische Anstalt Helgoland

Abstract: 
Populations of Littorina mariae, L. obtusata and L. saxatilis from the coast near Roscoff (Brittany), from the North Sea islands Helgoland Sylt were investigated with regard to several characters of their reproductive biology. Important factors are body size and weight, maturation size, shell thickness, sex ratio and reproductive effort of adults as well as number, size and mortality of embryos. Mature L. saxatilis individuals inhabiting sandy shores are smaller and have thinner shells and higher reproductive effort than those on rocky coasts. On shores with loose and semi-permanent boulders the adults are clearly larger. Interannual variations in some life history parameters may be explained by changes in food supply. In populations with small adults, .female..female. are bigger than .male..male.. In localities where L. mariae and L. obtusata occur sympathically, a tendency to accentuate interspecific contrast is recognized. Life history patterns, especially in L. saxatilis populations, show two tendencies: (a) a rapid increase of shell-size and thickness, which offers better chances of survival and of maximizing clutch-size and clutch-numbers during life-time; (b) early entrance into maturity leads to accelerated reproduction, but life expectation is reduced. Both tendencies are balanced by the action of biotic and abiotic factors.

Harvard-Zitierstil: GALLARDO, C. and GOTTING, K. (1985) INVESTIGATIONS ON REPRODUCTIVE-BIOLOGY IN 3 LITTORINA SPECIES OF THE SOUTHERN NORTH-SEA, Helgoländer Meeresuntersuchungen, 39(2), pp. 165-186. https://doi.org/10.1007/BF01997448

APA-Zitierstil: GALLARDO, C., & GOTTING, K. (1985). INVESTIGATIONS ON REPRODUCTIVE-BIOLOGY IN 3 LITTORINA SPECIES OF THE SOUTHERN NORTH-SEA. Helgoländer Meeresuntersuchungen. 39(2), 165-186. https://doi.org/10.1007/BF01997448