The long-spined sea urchin, Diadema antillarum is responsible for the maintenance of coral reef health throughout the Caribbean. However, in the early 1980s a region wide epidemic reduced their populations by an average of 98%, which stimulated the widespread macroalgal phase shifts that currently plague the Caribbean. Despite the fact that restoration of D. antillarum is widely believed to be a conservation priority we know surprisingly little about their physiology and behaviour. The aim of this project is therefore to explore the innate responses of this keystone species to numerous external environmental and physical factors, such as food and habitat availability, rising sea surface temperatures and ocean acidification, which may affect the success of targeted conservation efforts. These questions will be answered through a series of laboratory manipulations on urchin specimens collected from nearby reefs.
This project is predominantly lab based and therefore can be undertaken by nondivers, although additional data can also be gathered from dives.
In the Caribbean, there are a number of core issues that have been affecting the biodiversity of the coral reefs – including the mass mortality of keystone sea urchins that have allowed algal colonisation of reef areas, an invasive species originally from the Indo-Pacific (lionfish) that acts as a predator on reef fish which has been spreading across the Caribbean, and overfishing of reef fish by local communities. Opwall has two monitoring sites in Honduras: one is on the island reefs of Utila and the second on the coastal barrier reef of Tela. At both sites, teams of Opwall scientists and students collect annual monitoring data to assess temporal patterns of ecosystem change, alongside novel research to address key management priorities and gaps in our current understanding of tropical marine coastal ecosystem function.
Our marine sites are hot and usually dry, but with occasional storms.
Fitness level required
Low. Some fitness is required if including in-water activities, but conditions are relatively easy.
Facilities are comfortable but basic. There is phone signal and limited wifi that is often unreliable.