lMOVEMENT AND FORAGING BEHAVIOURS OF SURF SCOTERS WINTERING IN HABITATS MODIFIED BY SHELLFISH AQUACULTURE

摘要: I investigated movement patterns and foraging effort of surf scoters wintering in two sites with shellfish aquaculture, one clam the other mussel prey. Scoters at site exhibited very little high fidelity, whereas habitats much larger movements. These habitat-specific were likely related to temporal prey availability; clams remained relatively stable while mussels declined dramatically, depleted by scoters. Mussels occurring on aquaculture structures novel favoured sea ducks because they occurred higher densities less defensive morphology than intertidal mussels. Surf did not respond depletion these intensifying efforts but rather moved alternate feeding areas. Though has modified coastal British Columbia, changes have compromised scoter opportunities and, some cases, improved availability quality