Climate, Currents, and Connectivity: The Dynamics of Larval Dispersal

Many adult marine creatures are sedentary or sessile; therefore dispersal of their young and juveniles is a critical component of their population health. Connectivity, the patterns of delivery of young between populations, is an important component of coastal and marine spatial planning because it deals with the spatial and temporal connections between the populations and ecosystems targeted for protection. Protection of the connectivity between populations increases the resilience of populations and ensures the continued use of ecosystem services.

Marine plants and animals release young into the ocean where they are transported by ocean currents until they are large enough to settle back into adult habitats. Many oceanographic features, such as fronts, act to aggregate these small members of ocean communities. In response, larger, mobile marine predators are also attracted to these features – in pursuit of resources and prey. Consequently, regions of the ocean with strong physical gradients contain creatures spanning in size from microscopic plankton to large predators, like fish, seabirds and turtles.

In the coastal ocean, fronts and other oceanographic features are common and can be predictable in both space and time. However, as our climate changes, these physical gradients and the transport patterns associated with them are also changing. New results from two large-scale, interdisciplinary programs offer insights into how a changing physical ocean environment affects larval dispersal and, in turn, marine ecosystem dynamics.