Knowing what a reef’s needs are

Coral reefs, often called the “rainforests of the sea,” support rich biodiversity and an abundance of life. Hard corals play a similar role to trees in a rainforest, offering habitat, energy production, chemical, and nutrient cycling, and other crucial services that support the ecosystem’s existence and prosperity.

While coral reefs are home to millions of species, corals stand out for their significance. Discussions about reef degradation or restoration typically spotlight these key organisms.

This focus does not diminish the importance of other species when planning reef management projects. A functioning ecosystem needs all its diverse and interconnected organisms. Hence, we advocate for a holistic approach to reef management.

Programs that exclusively aim to increase coral abundance without considering diversity, addressing root problems, or protecting other species will inevitably fail to preserve their reef resources over the long term.

This holistic approach may involve land-based projects to control wastewater and erosion, collaborating with local communities to manage fishing and tourism, or working with NGOs to educate and raise awareness. It could also encompass initiatives to manage coral predators, boost the population of other key reef species, or enhance the diversity of habitats within a reef.

As reef stewards focusing on hard corals, we can contribute to protecting, managing, or even restoring structural or biological reef components lost due to human activities or natural disasters.

Restoring hard corals may bring back many fish and invertebrate species recently lost, marking our project as a success. To plan effective reef management programs, we first need to understand the requirements for healthy corals, allowing us to choose the right restoration project for each unique location.

Requirements for a Healthy Reef

As you learned in the EMP course, corals need five basic factors to thrive:

  1. Sunlight: Corals’ resident zooxanthellae require consistent and adequate light levels. Both increasing or decreasing light levels can hinder growth and cause stress.
  2. Temperature: Corals are sensitive to temperature changes. Even minor deviations can lead to widespread issues.
  3. Water quality: Corals need clean, low-nutrient waters free of pollutants or sediment.
  4. Structure: Corals require a solid structure for attachment and growth. They cannot grow spontaneously in the sand.
  5. Symbioses: Corals rely on many other fish and invertebrates in the reef to maintain the ecosystem’s balance.

A comprehensive understanding of these five factors and their intricate relationships is critical to identifying reef problems. When observing the reef or working in it keep these ecological factors in mind, and ask yourself what is missing.

Reefs near areas of high land development may suffer water quality issues due to erosion and sedimentation. Overfished sites might be unbalanced, or their structure may be lost due to destructive fishing practices. If you’ve observed your reef site for a few years, you’ve likely witnessed the effects of elevated temperatures during ENSO cycles, causing mass coral bleaching and mortality. No matter where your reef is located, it’s likely facing at least one chronic threat.

As local reef stewards, our task is to mitigate these threats and restore marginalized or lost areas.