Tsunami-driven rafting: transoceanic species dispersal and implications for marine biogeography

Following the arrival in June 2012 of a large fishing dock from Misawa and of several Japanese vessels and buoys along the Oregon and Washington coasts (table S1), we established an extensive contact network of local, state, provincial, and federal officials, private citizens, and environmental (particularly "coastal cleanup") groups, in Alaska, British Columbia, Washington, Oregon, California, and Hawaii. Between 2012 and 2017 this network grew to hundreds of individuals, many with scientific if not specifically biological training. We advised our contacts that we were interested in acquiring samples of organisms (alive or dead) attached to suspected Japanese Tsunami Marine Debris (JTMD), or to obtain the objects themselves (numerous samples and some objects were received that were North American in origin, or that we interpreted as likely discards from ships-at-sea). We provided detailed directions to searchers and collectors relative to sample photography, collection, labeling, preservation, and shipping, including real-time communication while investigators were on site. In addition, a timely alert network permitted some of us (especially JWC and JAM) to respond to reports of objects freshly washed ashore on the Oregon and Washington coasts. Marine biologist colleagues in AK, BC, WA, OR, CA, and HI further responded to our requests to seek out and examine objects to which we had been alerted as newly washed ashore, and to then acquire samples if practical.