Connectivity
Understanding how communities are connected and which systems are self-recruiting or dependent on an adjacent source for larvae recruits is important for managers. Photo © S. Summerhays
Understanding and maintaining the ecological patterns of connectivity is an important component of coral reef management. Connectivity describes the extent to which populations in different parts of a species’ range are linked through the exchange of eggs, larval recruits, propagules, juveniles, or adults.
Imagine what might happen if a particular reef is strictly protected while its neighbor reef, historically an important source for larvae recruits, is zoned as a high impact tourism area. The likelihood of a continued relationship (supplying coral recruits) is certainly reduced.
Knowing how communities are connected, and which reef communities are largely self-recruiting, is important for managers. Yet, in most cases, we do not have this information.
Connectivity has been identified as a key consideration in the design and management of coral reef resources; however, acquiring information about connectivity is quite challenging.
Recent advances in science and technology are providing answers to the connectivity questions, indicating that a substantial amount of self-recruitment1 occurs within reef communities and that there is great variation in dispersal distances.2 Models are also being used to predict the connectivity of adjacent or distant reefs3.
Video
Coral Reef Connectivity (1:14)
Will Heyman discusses coral reef connectivity.
Because most locations don’t have the benefit of focused scientific research to answer these questions, some rules of thumb for connectivity have been developed and are being refined.
Connectivity is a key consideration in the design and management of coral reef systems. Maps of potential protected area sites can help managers identify connectivity issues. Photo © S. Wear/TNC
In the absence of connectivity information, rules of thumb can be considered for MPA and MPA network design.
For more information see Resilient MPA Design and the special section on Designing for Connectivity in this toolkit.
1 Almany et al. 2007, Becker et al. 2007
2 Palumbi 2003a, Palumbi 2004, Jones et al. 2007
3 Cowen et al. 2006, Kobayashi 2006, Bird et al. 2007