The humpback “Timmy/Hope” positions were geolocated by hand from the image shown at the Danish Minister’s press conference — no GPS tracker data is publicly available. The points are therefore date-only (the source gives a calendar day, not a time of day) and carry large positional uncertainty, shown as the cyan rings (up to ~50 km). The moving cyan dot glides between each day’s mean position, so its on-screen pace reflects day-to-day net movement, not real swimming speed.
Ship positions are AIS (Automatic Identification System) records from the Danish Maritime Authority. Each Class A/B vessel transmits its GPS position periodically; we keep only transmissions inside the Kattegat box during , thinned to about one point every 3 minutes per vessel. A marker is interpolated between a vessel’s fixes: solid where a fix is confirmed nearby, faded (with a faded trail) where the position is estimated across a coverage gap, and hidden where there is no data — so nothing is drawn across long blanks. Marker size marks large vessels (≥150 m).
Navigational warnings: Danish Notices to Mariners (EfS). Built with an open Python tool; basemap © CARTO/OpenStreetMap.