Communities at Sea maps show linkages between fishing communities and the fishing places that are most important to them. The maps are developed by linking Federal Vessel Trip Report (VTR) data (trip dates, gear type, number of crew on board, trip locations) with vessel permit data (vessel length, ports associated with each vessel).
The relative importance of fishing areas is measured in “fisherdays” based on the number of days that vessels spent fishing in any given area and the number of crew members that were aboard. Fisherdays do not reflect other variables such as number of pounds landed, value, or other common measures of fishing activity or effort; however, the map legends use the term “fishing effort” for simplicity. The maps can be interpreted as showing community presence in ocean areas.
Two types of Communities at Sea maps are available: regional maps and port-specific maps.
Regional maps show where fishing occurs with different gear types—bottom trawl, dredge, gillnet, longline, or pots and traps—and the relative importance of different places. The dataset includes vessels from all ports. For example, the places frequented by fishing vessels using bottom trawls or dredges can be visualized separately. Regional maps are shown by default or can be viewed by selecting All Ports in the Location dropdown menu.
Port-specific maps indicate the most important places for fishing vessels associated with a selected port. The outline on the map represents where fishing vessels from that port conduct 90 percent of their fishing activity.For example, the places frequented by fishermen from New Bedford, Massachusetts, who fish using gillnets can be mapped separately from places frequented by gillnet fishermen from Portland, Maine. In addition, the places where New Bedford vessels fish with bottom trawls can be mapped separately from places that they fish with dredges. Port-specific maps can be viewed by selecting a port in the Location dropdown menu,
To produce the Communities at Sea maps, all data were aggregated to the community level, and none of the maps represent the fishing areas, or hot spots, of any individual fisherman or fishing vessel. Draft maps were reviewed and refined in consultation with fishermen in several ports. The following considerations and caveats guided and emerged from those conversations:
- These maps represent the locations and intensity of fishing during particular time periods. If these maps are considered during planning or permitting decision-making processes, it is critical to recognize that additional important fishing areas may not be represented, as locations frequently shift due to many factors such as market dynamics, regulatory changes, and rotational fishing strategies.
- These maps only show fishing conducted by vessels holding federal fishing permits. The maps do show a portion of state-licensed activity because many state-licensed vessels engaged in ocean fishing also hold federal permits and therefore submit VTRs. State-licensed fishing activity includes whelks (“conch”), striped bass, black sea bass, and lobster.
- Maps showing areas for fishing with fixed gear (pots, traps, gillnets) will tend to be more accurate than maps showing fishing using mobile gear (trawls, dredges), and maps showing single-day trips will tend to be more accurate than maps showing multi-day trips. This is because of the nature of the fishing activity and record-keeping regulations; fishermen are only required to report one geographic position (point location) per trip on VTRs unless switching to a new gear type or moving into a new statistical area.
- These maps can be supplemented with maps based on Vessel Monitoring System data (available for select federally managed fisheries); see the Commercial Fishing Vessel Activity Theme Map or the Data Explorer (click Commercial Fishing and then Vessel Activity). Overlaying and comparing the VTR-based maps with VMS-based maps reveals substantial agreement between the two, and the VMS maps provide additional useful precision for some fisheries.
- Fisheries and fisheries data are complex, and there are many options for mapping fishing activity, each with strengths and weaknesses. These maps are intended as a starting point to help target and guide direct engagement and consultation with specific affected fishing communities during diverse ocean planning, permitting, and management decision-making processes.
- For some types of decision making (e.g, detailed construction plans for energy infrastructure) much finer scale information and data than can be obtained using either VTR or VMS data will be needed, ideally provided by fishermen.
Original VTR data were obtained from NOAA NMFS Northeast Fisheries Science Center, with methodology, data processing and cartography provided by staff at Rutgers University. For information about methodology and interpretation of the data, see Creating Space for Community in Marine Conservation and Management: Mapping ‘Communities at Sea’ by Kevin St. Martin (Rutgers) and Julia Olson (NOAA).