Vegetative propagation and spore-based recruitment in the carrageenophyte Chondracanthus chamissoi (Gigartinales, Rhodophyta) in northern Chile

In the present study we compared vegetative and spore-based propagation for Chondracanthus chamissoi (C. Agardh) Kützing. Monthly field observations were made over a 1-year period at Puerto Aldea, Tongoy Bay, Chile. Data were collected both outside and within a bed of C. chamissoi. Vegetative propagation was assessed via attachment of drifting fronds to shell-encrusted concrete blocks at both sites. Germination of spores was recorded on the same shell substrates. Substrate re-adhesion varied seasonally between sectors. Highest averages occurred within the algal bed between January 1997 and March 1997. The number of sporelings showed two peaks of maximal recruitment in spring and summer months (January-March 1997 and September 1997-January 1998). Spore-based propagation is an important mechanism of seasonal regeneration of biomass in the C. chamissoi bed; however, re-attachment of fronds may have been important in maintaining production of the bed during the period of maximum biomass accumulation.