Growth and survivorship of clonal fragments in Zoanthus solanderi Lesueur

• Published in: Journal of experimental marine biology and ecology 1988-01, Vol.123 (1), p.31-39
• Main Author: Karlson, R.H.
• Format: Article
• Language: English
• Subjects: Animal and plant ecology; Animal, plant and microbial ecology; Animals; Biological and medical sciences; Clonal fragmentation; Consequence of aggregation; Demecology; Enhanced survivorship; Fundamental and applied biological sciences. Psychology; Growth inhibition; Marine; Protozoa. Invertebrata
• ISSN: 0022-0981; 1879-1697
• DOI: 10.1016/0022-0981(88)90107-4

Modular growth in clonal organisms results in aggregated groups of related individuals. Environmental disturbances can alter this underlying dispersion pattern by breaking apart clones and dispersing fragments into aggregations of conspecifics or to locations outside aggregations. I have evaluated the consequences of fragment dispersal and aggregation in a clonal animal which experiences turbulent conditions during storms and undergoes fragmentation. Over a 1-yr period, the fate of experimentally dispersed fragments (i.e., implants and explants) depended on initial fragment size and location. As in most clonal organisms, fragment survivorship was size-dependent; large fragments had higher survivorship than small fragments. Outside aggregations, unattached explants had low survivorship while artificially stabilized explants had high survivorship and grew rapidly. Fragments implanted within a large aggregation were stabilized by the growth of neighboring conspecifics onto the rubble substratum bearing each fragment. These implants survived better than unattached explants, but grew more slowly than artificially attached explants. I conclude that enhanced survivorship and growth inhibition are consequences of the aggregation of zoanthid fragments. Enhanced survivorship within aggregations should reinforce underdispersion in this clonal species and promote the formation of polyclonal aggregations of conspecifics. The benefits of such mixed aggregations may involve the enhancement of external fertilization, outcrossing, and cooperative, rather than aggressive, intraspecific interactions.