Data Licenses & Attribution
Crab Keeper is made by emaration.site. This page lists the data the map is built from and the terms our own data is shared under.
Map data
Basemap data © OpenStreetMap contributors, available under the Open Database License (ODbL) 1.0.
OpenStreetMap® is open data. The cartography and any derived tiles remain subject to the ODbL terms of the underlying data.
The vector basemap is a Protomaps extract of OpenStreetMap (ODbL), water/earth polygons from osmdata.openstreetmap.de (ODbL), Natural Earth (public domain), and Daylight Landcover derived from ESA WorldCover (CC-BY 4.0). Protomaps code is BSD-3; the map design is CC0.
Our spot data — shared back under ODbL
Crab Keeper's public crabbing and clamming spots are published under the ODbL 1.0, the same license as the OpenStreetMap data they sit alongside. Download the full set as GeoJSON:
Attribute it as: Crab Keeper public spots (crabkeeper.com), ODbL 1.0.
What is not in it: spots marked secret, dropped-pot pins, catch logs, photos, and anything tied to an account. Those are private to the person who saved them and are never included in this export — it carries no user identifiers at all. Only spots explicitly published to the community map appear here.
Aerial overlay
The optional Pro aerial layer is USGS National Map imagery (public domain). Map services and data from The National Map are free and unrestricted. Credit: Map services and data available from U.S. Geological Survey, National Geospatial Program.
It is fetched same-origin through our Worker, the same rule as the basemap. A dead overlay must never blank the street map.
Tides and currents
Tide predictions and slack-water timing derive from NOAA CO-OPS station data, a work of the United States government in the public domain.
Predictions are estimates. They are not a substitute for local knowledge or official notices.
Seasons, closures and regulations
Season, bag, size, and licensing information is copied by USPS state from that state's fishery agency (ODFW, WDFW, CDFW, and the other coastal agencies in Licenses) with the date it was retrieved. Oregon shellfish-safety closures are requested from the Oregon Department of Agriculture when the pin is in Oregon.
Crab Keeper is advisory only. Closures change, sometimes at short notice. Always check that state's current notices before harvesting, and follow posted local rules.
Software
Built with Leaflet (BSD-2-Clause), Protomaps (BSD-3 / CC0 map design), React (MIT) and Lucide icons (ISC), running on Cloudflare Workers.