Using local ecological knowledge to inform fisheries assessment: measuring agreement among Polish fishermen about the abundance and condition of Baltic cod (Gadus morhua)

Although fisheries managers often attempt to incorporate stakeholders' views into development of policy options, integration of fishermen's local ecological knowledge into biological assessments remains uncommon. Using the case of the eastern Baltic cod (Gadus morhua) resource, this article documented local ecological knowledge about a managed fishery stock. In 2012 and 2013, local media reported that fishermen were observing increased occurrences of cod with poor body condition (skinny cod) in their catches from waters off Poland. Polish cod fishermen were interviewed (n = 31) to quantify the strength of their agreement about the abundance and body condition of cod. Agreement among fishermen was assessed about trends in abundance and occurrence of skinny cod, as well as the mechanisms explaining those patterns. Cultural consensus analysis showed strong agreement among Polish fishermen that skinny cod may be attributed to overfishing on sprat, a key prey species. Fishermen and scientists observed similar declines in the abundance and condition of cod along the Polish coastline; however, they may perceive causes of those changes differently. Generalized additive models were used to show that trends in fishermen's observations of abundance and skinny cod occurrence may be partially explained by variation in temperature, salinity, and sprat abundance.