Acropora cervicornis Propagation Guide
Propagating staghorn coral (Acropora cervicornis), a Critically Endangered Caribbean reef-builder propagated chiefly through conservation aquaculture: ocean and land nurseries, fragmentation, and reef outplanting.
Overview
Acropora cervicornis, the staghorn coral, is a Western Atlantic reef-builder with thick, upright branches that can grow in excess of 2 metres in height. It is found from the Florida Keys and the Bahamas to the various Caribbean islands. As an Acropora, its colony of small polyps lays down a calcium carbonate skeleton, with symbiotic algae producing energy through photosynthesis. Its propagation is overwhelmingly conservation-driven rather than a hobby activity.
Reproductive Mode
Fragmentation is the most common mode of reproduction for staghorn coral, where branch breakage from storms or disturbances leads to new colony establishment. This natural asexual process is exactly what restoration aquaculture harnesses to multiply the species.
Fragging / Asexual Propagation
The Coral Restoration Foundation began artificial restoration in 2007, cultivating colonies in an offshore nursery, fixed on discs or hung from fishing lines, until they achieved 30 cm in diameter before being planted onto natural coral reefs. Staghorn grows rapidly, adding up to 5 cm of new skeleton for every 1 cm of existing skeleton each year, which makes nursery propagation effective.
- Healthy branches are fragmented from donor colonies within a restoration programme.
- Fragments are mounted on discs or suspended on lines or coral trees in ocean or land nurseries.
- Frags are grown out until large enough to survive on the reef.
- Grown colonies are outplanted onto degraded natural reefs.
Conditions for Propagation
Nursery and aquarium fragments need stable, warm reef conditions; temperature increases make staghorn more susceptible to bleaching events, so steady conditions are essential. As an Acropora, it requires high light and high flow and stable alkalinity, calcium and magnesium to calcify.
Sexual Reproduction
Staghorn corals are simultaneous hermaphrodites that engage in broadcast spawning typically restricted to late summer, in July and August, occurring several days after a full moon. Sexual reproduction is used in restoration to maintain genetic diversity alongside fragmentation.