9781934874424-ch12

Mangroves as Fish Habitat

Processes Affecting Movement and Survival of a Juvenile Fish in Mangrove Creeks (Extended Abstract)

Andrew B. Barbour and Aaron J. Adams

doi: https://doi.org/10.47886/9781934874424.ch12

Despite an increasing recognition of the ecological and economic values of estuarine and coastal ecosystems, we still lack a complete understanding of many of the processes contributing to the services these ecosystems provide. Such knowledge is essential as many of these ecosystems are in a continued state of global decline. For example, at least 35% of mangrove area was lost between the 1970s and 2000 with annual loss rates of 1–2% (Valiela et al. 2001). Concurrently, indirect habitat alterations degrade ecological services of mangrove systems. While the effects of the loss and degradation of services such as coastal protection, carbon sequestration, and the provision of raw materials are more easily quantified, the effect of lost coastal ecosystem function on the maintenance of marine and estuarine communities is not easily delineated (Barbier et al. 2011).

A meta-analysis of long-term data on coastal ecosystems revealed severe historical declines in multiple coastal ecosystem services, including a 33% decline in the number of viable fisheries and a 69% loss of nursery habitat (Worm et al. 2006). These two services are intimately linked since nurseries supply new recruits to support exploited fisheries. In general, coastal nurseries (e.g., mangroves) are believed to increase survivorship of young fish and thereby influence community structure and increase biomass on connected adult habitats (Dahlgren and Eggleston 2000; Grol et al. 2011; Barbour 2013). This enhancement is important in the support of fisheries through increased recruitment, as well as for maintaining natural ecosystem structure. For example, a nursery-enhancing requirement for species that control macroalgal growth on coral reefs protects against phase shifts from coral to macroalgal reefs.