Propagating Montipora digitata
A propagation guide for the branching, finger-like coral Montipora digitata of the family Acroporidae, covering branch fragmentation, spawning biology, and the Phestilla nudibranch pest.
Overview
Montipora digitata is a branching coral of the family Acroporidae with a digitate or bushy form built from vertically aligned, anastomosing branches. According to Wikipedia, colonies form hemispherical mounds reaching over 40 centimetres in diameter, with small, deeply embedded corallites that give a pitted surface, and they are typically pale cream, yellow, or brown. The species occurs in shallow water across East Africa and the Indo-West Pacific.
Reproductive Mode
M. digitata is a simultaneous hermaphrodite that spawns annually. Packets of eggs and sperm are released into the water column and rise to the surface, where cross-fertilisation occurs as gamete packets from different colonies intermix. It is a zooxanthellate species whose photosynthetic symbionts can supply up to 90 percent of its energy, supplemented by captured plankton.
Fragging / Asexual Propagation
The branching habit makes M. digitata one of the simplest Montipora to multiply: individual finger branches are snapped or cut from the colony and mounted to a plug or rock. Each fragment regrows into a new bushy colony of anastomosing branches under medium-high light and flow. No cutting saw is required for thin fingers, though sharp bone cutters give cleaner breaks.
- Snap or clip a finger branch 2-4 cm long from the parent colony.
- Mount the branch upright on a plug with reef-safe adhesive.
- Position under medium-high light and water movement.
- Allow the base to encrust and new branches to form.
Common Challenges
The Montipora-eating nudibranch is the chief hazard. An undescribed Phestilla species is reported to feed on the genus, and the described pest Phestilla subodiosus preys specifically on Montipora; it has caused significant commercial harm now that the genus is intensively aquacultured and maricultured. Eggs hidden in branch crevices make complete removal difficult.