Artificial Reefs are man made structures built to recreate reefs, but for several different reasons.
Firstly and most often, Artificial reefs are built to promote marine life either in areas with a featureless bottom or where reef systems have been lost and need replenishing.
Artificial Reefs are also used to control Erosion, block shipping passages and to create waves to improve the surf.
Artificial reefs built with the specific aim of promoting marine life can come in all shapes, sizes and forms. Some Artificial reefs are purposely built using objects such as Concrete or PVC Reef Balls, whereas others are manmade items that have been sunk such as Wrecks (Boats, Planes, Tanks etc.). Artists have also contributed, creating underwater sculptures and memorials.
Regardless of construction method, artificial reefs provide a hard substrate which allows algae and invertebrates (barnacles, oysters and Corals) to attach, creating a habitat that provides both food and shelter. This attracts other forms of marine life, including large assemblages of fish.
Examples of Artificial Reefs
Our very own wreck in Grand Cayman was purposely sunk to not only create a wreck site, but to also act as an artificial reef. The wreck is now teaming with life making it perfect for both wreck divers and animal lovers. The Kittiwake made the list for top 10 wrecks over the world, and if your lucky you may even see the Goliath Grouper that likes to hide out in the lower decks.
“The Silent Evolution” by artist Jason De Caires Taylor
This is a collection of sculptures on the sea floor in Cancun and Isla Mujeres Marine Park, Mexico. The installation will create a new home for a variety of aquatic life and is designed to reduce the impact over half a million tourists have on the areas of natural reef every year.
As bleaching events are are happening more often than ever before, we are seeing huge parts of reef systems die. Coral gardening involves the propagation and growth of coral fragments either in labs, aquariums or open water. When the coral has reached the correct size/maturity, it is manually attached to a substrate in the hope that it will grow and eventually attach itself – creating a coral reef.
Pros of Artificial Reefs
Coral reef restoration
They encourage high levels of bio-diversity
They can be used as a tool to rebuild fish populations, both for conservation and the fishing trade
They can ease fishing pressure on natural reefs by creating a new location for fisherman to fish
Artificial reefs are a great way to utilise objects that would otherwise go to landfill
Artificial reefs can aid the diving and tourism trade, creating new dive sites which are both beautiful and teaming with life
Cons of Artificial reefs
Some materials used to create artificial reefs are actually more damaging to the Eco-system and as they corrode/degrade can release toxins into the marine system
They may promote irresponsible refuse management – dumping rubbish in the Oceans and claiming its to create an artificial reef
Overfishing instead of biomass – laws need to be put in place so these systems are not overfished
Sites for an artificial reef must be meticulously studied, and if not chosen correctly can actually damage other reefs in the vicinity and even the marine life around it