Throughout the world, the spread and establishment of non-native marine and estuarine species is on the rise. Various transfer mechanisms or vectors are responsible for the dispersal transfer and spread of such species among coastal ecosystems. Our research actively explores several aspects of vector ecology: (a) the magnitude, intensity, operation and dynamics of particular vectors and (b) the effect of vector management strategies to reduce the risks of species transfers and associated impacts.
There exist a diverse array of vectors, and their relative importance varies in space and time - in terms of both magnitude of species transfer and number of resulting invasions (i.e., self-sustaining populations). Our current research is designed to characterize and test hypotheses about several of the dominant vectors for marine species in North America, including: Some of the more important invasion pathways that we study are:
In particular, vectors associated with ships (principally ballast water and hull fouling) are a major focus of extensive research by MIRL scientists. We have collected measurements of the diversity and density of organisms that arrive in ships (ballast tanks) and on ships (hulls). We also conduct temporal analyses or repeated sampling aboard selected ships to estimate patterns of survivorship (transit success) across a variety of taxonomic groups, geographic regions, and voyage conditions.
Other components of our research on ships examine management strategies, including the efficacy of ballast water exchange (a management action to reduce organism transfer) and methods to verify ballast water exchange. In addition, we have established a joint program with U.S. Coast Guard to track nationwide survivorship studies to understand rates of mortality and biotic introduction.
Understanding delivery patterns for invasive species is critical to managing invasion risk, and so is central to our research activities. Further information on shipping and ballast water management patterns is available on the National Ballast Information Clearinghouse website.