Coral competition for space
Coral reefs fulfil many ecological functions such as maintaining the diversity, providing habitats and
shoreline protection. One of the most important reef building corals is the Aropora cervicornis known
as Staghorn. Over the past decades many corals have disappeared due to human and natural disturbances.
Acropora species populations are also heavily damaged in the Caribbean since the 1980s by the
white band disease (WBD). Also predation and competition between organisms can influence the
growth and survival of corals. The Acropora species A. cervicornis is an important reef building coral
which can be a dominant species because of their relative fast growing abilities. This gives them the
ability to overgrow other soft and stony corals. However algal growth is faster than the growth of A.
cervicornis, making the coral species susceptible to be overgrown by other organisms besides corals.
Reefs can get overgrown by algae like seen around Saba, a small island in the Dutch Caribbean. Together
with St. Maarten, St. Eustatius and the Turks and Caicos Islands Saba is part of the RESCQ (Restauration
of Ecosystem Services and Coral reef Quality) project. This project aims to restore Acropora
populations included the A.cervicornis by establishing a coral nursery. In this research the influence of
predation and competition of other species on the growth and fitness of A.cervicornis will be studied.
In this experiment A.cervicornis fragments were planted on the reef where different cleaning treatments
were tested. Depending on the treatment the area around the planted fragments was cleaned
from algae. Eventually 14 out of 15 fragments were healthy with a positive growth rate, there was no
significant difference between the cleaning treatments. Some fragments showed predation signs such
as spot-biting, but after polyp-recovery the fragments gained a positive growth.