Sentinel Survey

A sentinel survey is a long-term, fixed-design scientific survey that tracks indicators of stock and ecosystem state at consistent stations, gear, and timing so that change over years reflects the resource and not the method. Sentinel programs often pair with cooperative research, using commercial vessels fishing to a standardized protocol to extend coverage where research-vessel time is scarce. The value is the time series itself: a survey index of abundance, size structure, or recruitment that feeds tuning into stock assessment and gives early warning of decline. Canada’s DFO sentinel fisheries in the Gulf of St. Lawrence are a documented example. Comparability across years is the binding requirement, so gear and protocol changes are avoided.