About Shark Tracker

A calm, public map of shark sightings along the California coast, starting here and growing from there.

What this is

Shark Tracker brings together open data about sharks: recent sightings from community science, historical incidents, historical satellite-tag tracks of tagged animals, and reports from visitors. It is a non-commercial project: there are no ads, no tracking and nothing for sale. Sharks are a normal, important part of a healthy ocean; the goal is curiosity and good information, not fear.

Data sources, licenses and credits

Every point on the map keeps its source, license and credit, shown when you open it, with a link to the original record where one exists.

• iNaturalist

  Recent shark observations by the public in California, with photos where available.

  License: Each observation and photo carries its own Creative Commons license chosen by the observer (CC0, CC BY, CC BY-NC and variants). Observations without a CC license are not shown.

  Credit: Shown as “© observer, license via iNaturalist”, with a link to the original observation. Photos keep their own license and credit.

• GBIF (Global Biodiversity Information Facility)

  Occurrence records from museum collections and research datasets (iNaturalist-sourced records are skipped to avoid duplicates).

  License: Per-dataset licenses (CC0, CC BY or CC BY-NC); photos keep their own license.

  Credit: Shown as “dataset title, license via GBIF”, with a link to the GBIF occurrence page.

• CDFW Shark Incident Database

  Historical shark incidents in California, 1950 to February 2022, as published by the California Department of Fish and Wildlife. CDFW gives approximate locations only, so every incident is marked “approximate location”.

  License: CC BY, via the California Natural Resources Agency open data portal.

  Credit: California Department of Fish and Wildlife.

• IOOS Animal Telemetry Network · Stanford Block Lab (TOPP)

  Historical satellite-tag tracks of 199 sharks (2002–2013) from the Tagging of Pacific Predators program: modeled daily positions, at most one per 6 hours. They do not show where animals are today.

  License: IOOS ATN ERDDAP license: may be used and redistributed for free; not intended for legal use; no warranty.

  Credit: Stanford University Block Lab (TOPP) via the IOOS Animal Telemetry Network.

• Shark Tracker reports

  Sightings sent by visitors through this site. They show as Unverified until a moderator reviews them.

  License: CC BY 4.0, credited as “Report by a Shark Tracker visitor”.

  Credit: Shark Tracker visitors.

• Basemap

  Map tiles and styles.

  License: OpenFreeMap styles; map data © OpenMapTiles and © OpenStreetMap contributors (ODbL).

  Credit: OpenFreeMap, OpenMapTiles, OpenStreetMap contributors.

Locations from iNaturalist may be deliberately blurred by the source; those points say “approximate location”. Data from sources that do not allow public redistribution is never used.

Privacy

When you send a report, we store:

• the location you chose, the time, and the details you entered (species, count, size, behavior, notes);
• an optional photo, re-encoded on our server with all metadata (EXIF, including GPS and camera data) removed;
• an optional email address, used only if a moderator has a question. It is never shown or published.

To limit spam, your IP address is turned into a salted one-way hash and kept for a short time for rate limiting (5 reports per hour). The raw IP address is never stored. There are no analytics or advertising cookies; the only cookie is the moderator sign-in.

Reports are published under CC BY 4.0. If you want a report removed, contact the project and a moderator will hide it.

Moderation

New reports appear right away, marked Unverified. A moderator can mark a report Verified (for example when the photo clearly shows a shark) or hide it.