Throughout the world's oceans, hard structures such as natural reefs provide ideal marine habitats. Reefs provide hard surfaces to which plants, coral, and sponges can attach, and thereby provide food and shelter for many types of fish. Recently, workers in the fishing industry have tried to increase the amount of suitable habitat for fish by constructing artificial reefs from old metal objects and industrial materials and placing them in coastal waters. Artificial reefs have several benefits.Many fishers believe that by giving fish more places to gather and reproduce, artificial reefs have increased the populations of some species of fish. For example, a report from one extensive artificial reef program in the Gulf of Mexico shows that the number of red snapper fish harvested in the area has increased by as much as ten times compared with harvests a century ago. The increases in the number of fish caught began after the start of the artificial reef program.Artificial reefs can also improve the economic competitiveness of small-scale fishers. This is possible because small-scale fishers are able to create their own private artificial reefs in secret locations only they know. Currently, small-scale fishers struggle to compete with larger corporations because fishing grounds are limited in number and most are known to everyone. Creating fishing areas known only to the fishers who make them will help independent fishers support themselves and their local communities.Finally, artificial reefs are a good way to recycle materials no longer needed for other purposes. Artificial reefs can be made from old cars and other objects that are otherwise difficult to dispose of. Once these materials have been cleaned to ensure that no harmful chemicals remain, they can be placed in the ocean to serve as reefs for marine life. Artificial reefs thus provide a relatively inexpensive, environmentally friendly way to reuse materials.