Dynamics and Structure of Marine Populations and Communities

Tracking larval dispersal trajectories-

Photo Credit (above): Jonathan Stillman

Natural elemental tags are being developed for invertebrates (barnacle, native oyster, crabs) and fishes (cabezon, mudsucker) to answer a central question in marine ecology: how far do larvae disperse? Uptake of natural elemental markers recently have been used as larval tags for estuarine species that retain calcified structures throughout development. Our laboratory is extending this technique for the large majority of larvae that do not retain hard parts or develop in estuaries where chemical signatures are most distinctive. We were able to correctly identify natal origins of the rocky shore porcelain crab (Petrolisthes cinctipes)embryos >80% of the time among many sites that were located ~20 km apart along the exposed coast between the Gulf of Farallones to north of Point Arena. The study was repeated this summer to determine whether signatures of the sites are stable over time and to determine whether the same sources and sinks were evident. New funding recently was obtained to conduct laboratory validation studies of the technique and to apply it to controlling the spread of the invasive green crab Carcinus maenus.