Upscaling sexual coral restoration
optimizing survival and growth of Favia fragum settlers mass-reared in situUpscaling sexual coral restoration
optimizing survival and growth of Favia fragum settlers mass-reared in situSamenvatting
Coral reefs are of great importance for social, biological and economical purposes. However, due to global and local threats they are declining rapidly. One of the ways to sustain coral reefs is sexual coral propagation. While the sexual propagation of corals for reef rehabilitation has been successful in a few occasions, the survival of coral settlers after they are outplanted to the reef remains low. New methodologies need to be developed to enhance the survival of settlers. This could for example be achieved by increasing available nutrition sources for young settlers and reducing their competition with detrimental algae. To address this problem, survivorship of settlers of the brooding coral, Favia Fragum, was studied in an ocean-based larval rearing pool, in which feeding of Artemia salina nauplii (~300 nauplii L -1 ) and grazing by small-sized Diadema antillarum (test size: ~1.5 to 3.0 cm) was tested. Results showed a six-fold decrease of survival between the grazing treatments (15 - 16%) and the nongrazing treatments (90 - 95%). Feeding did not affect survival, but resulted in an increase in settler size between the feeding treatments (2.1 mm2 ) and the non-feeding treatments (1.7 mm2 ). These results indicate that grazing activity of Diadema antillarum resulted in a high mortality, leading this to be a non-effective method. However, feeding did increase settler size. Settler size is of importance for post-settlement survivorship as bigger settlers have higher chances of survival, thus possibly increasing post-settlement survivorship after outplanting. An alternative method needs to be established in order to reduce competition with detrimental algae. However, the feeding of Artemia salina nauplii is an effective method to increase settler size.
Organisatie | Aeres Hogeschool |
Afdeling | Toegepaste Biologie |
Partner | Aeres Hogeschool Almere |
Secore International | |
Datum | 2020-06-08 |
Type | Bachelor |
Taal | Engels |