Andros Barrier Reef

• Coral reef


  A line of coral polyp found in warm shallow seas
• Polyp


  • Tiny carnivorous (meat eating) animals
  • Live in groups called colonies
  • Have a mouth at one end surrounded by tentacles
  • Cannot move from their limestone homes
• Polyp reproduction


  1. Dividing its own body to form two polyps

  2. Producing sperm and eggs
• Limestone case


  Built by polyp around itself, using calcium from the water
• Polyp builds limestone case


  Remains after it has died and forms a foundation for another polyp to build on
• Coral reef


  Formed when these limestone formations increase
• Algae (zooxanthellae)


  • Shares home with coral polyp
  • Gives colour to coral
  • Photosynthesises and produces food for coral
  • Enjoys secure home, absorbs coral's waste
• Coral


  • Eats microscopic zooplankton
  • Waste absorbed by algae
• Fish excrete ammonia


  Absorbed by corals and algae and used for growth
• Coral reef


  Provides safe home for fish
• Andros Barrier Reef


  • Part of an extensive coral reef system in the Bahamas
  • Third most extensive coral reef system in the world
  • Parallel to the shoreline separated from it by a lagoon
• Andros Barrier Reef


  • Stretches for approximately 200 km
  • Shallow lagoon with mangrove forests separates the land from the main reef
  • Outer edge marked by a steep drop to a depth of over 2000 m
• Coral reefs


  • Act as buffer zones providing vital shoreline protection from storms and tsunami
  • Force waves to break early before reaching the islands, reducing coastal erosion and risk of flooding
• Coral reefs


  • Provide sheltered conditions for the growth of mangrove forests, which are important breeding grounds for fish
  • Support commercial and recreational fishing, sport fishing, cruising, snorkeling and scuba diving industries
• The reefs in the Bahamas bring in over US$150 million per year from tourism
• Andros Barrier Reef


  • Recognised as being one of the healthiest reefs in the world
  • Superb outdoor laboratory for scientific research
• Coral reefs are considered by scientists to be one of the most endangered ecosystems on the planet
• Management of coral reefs in the Bahamas


  • Shared by the Department of Marine Resources (DMR) and the Bahamas National Trust (BNT)
  • Government committed to protect 20 per cent of its near-shore habitat by 2020
  • Several National Parks and Reserves established to help preserve parts of the valuable reef ecosystem
• Andros West Side National Park


  • Includes Andros Island and part of the coral reef
  • Designated to balance longstanding traditions with resource conservation, recreational fishing and ecotourism
  • Developments strictly controlled
• North Marine Park and South Marine Park


  • Areas of conservation where some activities are regulated or prohibited, such as fishing and collecting wildlife, mining, vessel anchoring, scuba diving and the discharging of materials
• Crab Replenishment Reserve


  • Best land crab habitat in central Andros, set aside to ensure a sustainable crab population
• Exuma Cays Land and Sea Park

  • Coral nursery established to conserve and monitor threatened species prior to being planted back in the coral reef
• Joulter Cays


  • Plans to establish a new National Park to the north of Andros Island
  • Prized for its fishing and varied shallow water ecosystem
  • Under pressure from excessive fishing, damage from boats and marine discards
• Several organisations monitor the environmental quality of the reef ecosystem to assess coral bleaching and identify any harmful impacts from human activity
• The Andros Barrier Reef remains one of the healthiest reefs in the world
• Climate change and global warming - higher water temps. trigger a stress reaction in corals causing them to expel zooxanthellae. This has a huge effect on nutrient flows and causes the coral to become bleached, turning white. Eventually coral dies. Projections from climate models suggest that reefs in the Bahamas will annually experience thermal stress severe enough to cause bleaching after 2040
• Pollution - this can involve agricultural chemicals, sewage and silt, eroded from hillslopes and discharges by rivers. Silt causes the water to become cloudy restricting the penetration of sunlight used by zooxanthellae to p/s
• over-fishing - commercial fishing and intensive tourism can cause immense harm to the ecosystem, causing it to become unbalanced. Corals can be killed by physical contact with anchors, boat hulls and even people's feet. The harvesting of sponges is an important local industry but can also have a harmful impact on the reef ecosystem
• Marine-based pollution - this results from oil and chemical discharges from boats and ships. The Andros Barrier Reef is very popular for deep sea fishing an such discharges can be harmful to both corals and fish