Inlet Insights: Counting Boats, Estimating Effort

There are 2.5 million people with a Florida saltwater fishing license, making estimating the number of fishing trips people take (fishing effort) challenging.

The most guaranteed accurate effort estimation method is for FWC staff to count boats passing through inlets and pair this information with dockside surveys. Dockside surveys can be used to figure out how many of the counted boats went offshore and fished for reef fish. However, this method requires consistent in-person inlet monitoring so it is less cost-effective than other sampling methods. Additionally, it can be challenging for inlet observers to easily and accurately count boats in areas where there are not distinct inlets that offshore anglers have to pass through.

Mail Survey Questionnaire

Effort estimates are currently reliant on data collected through mail surveys. In Florida, anglers are surveyed by mail via the Florida Fish and Wildlife Conservation Commission’s State Reef Fish Survey (SRFS) and the National Marine Fisheries Service’s Marine Recreational Information Program’s (MRIP) Fishing Effort Survey (FES). These survey responses are combined with dockside interviews (similarly to boat counts) and used to estimate the total number of trips taken. This process of combining mail surveys with dockside interviews is currently considered the best available way to estimate fishing effort.

However, mail surveys require people to remember details of trips taken in previous months, which can be difficult to recollect. Additionally, because of the time it takes to send out, receive, and process mail surveys, estimates of effort that come from mail surveys can be slower than is ideal to generate for in-season management decisions. For example, understanding how many fish of a species are caught in real time is important so that we know how close we are getting to annual catch limit regulations.

Cellular location data is commonly used to estimate traffic patterns and to determine how many customers are shopping in stores. We hope to use cellular data to count how many boats pass through inlets and estimate fishing effort.

Cellular location companies use geolocation data collected from apps on your phone when you agree to let the app use your location. These companies only collect data on a sampling of people and use those locations to estimate total use of an area, using similar statistical methods as generating effort estimates from mail surveys.

Research is starting to be done on whether cellular location data can be used to estimate fishing effort, primarily for freshwater fisheries. We aim to test this method for saltwater reef fish fisheries. Using cellular location data would generate timelier estimates than mail surveys without relying on angler recollection, would remove the in-person requirement for observed boat count monitoring, and is more cost-effective than both mail surveys and observed boat counts.

Beginning in the spring of 2026, FWC staff are launching a new project in St. Johns, Duval, and Nassau counties with a goal of using directly observed boat counts paired with dockside interviews to determine if cellular location can accurately estimate effort and to compare these results to effort estimates to the current SRFS or the MRIP-FES mail surveys.

This project is being conducted in St. Johns, Duval, and Nassau counties, so if you see FWC out there please come say hi!