A study was conducted on observed interactions between a Portuguese purse-seine fishery and cetaceans. Cetaceans, primarily common dolphins (Delphinus delphis), were present during 16.9% of fishing events. The majority of these occurrences happened during the summer and early fall, and during the night. The presence of cetaceans was significantly linked to sardine (Sardina pilchardus) catches, effort and latitude/longitude. Encirclement of cetaceans occurred in 2.3% of fishing events, with moralities occurring in 1%. Common dolphin, bottlenose dolphin (Tursiops truncatus) and harbor porpoise (Phocoena phocoena) were all encircled, with mortalities only recorded for common dolphins. Estimated annual mortality rates for the common dolphin are 113 individuals.
Year
Journal/Publisher Name
ICES Journal of Marine Science
Volume (Issue #)
doi:10.1093/icesjms/fsv076
Contact information
amarcalo@gmail.com
Summary
Field Studies
Quantification of interactions between the Portuguese sardine purse-seine fishery and cetaceans
Study Type
Field study in the wild
Location
Portugal
Target catch
Sardine (Sardina pilchardus)
Effect on bycatch species
Cetaceans were present during 16.9% of fishing events; encirclement led to common dolphin mortalities
Effect on target catch
NA
Bycatch species
Fishing Gear