Top: locations of a subsample of active animal tracking (‘bio-logging’) studies superimposed on human population density. Data sources: 801 publicly visible animal tracking studies from the Movebank research platform (www.movebank.org) that are likely to contain data overlapping with the COVID-19 period (data extracted 18 May 2020). ‘Marine’ includes seabirds and other marine species, ‘avian’ refers to all other bird species, and ‘terrestrial’ are non-avian species living mostly on land. Population density data sourced from ref. 15 (data accessed 15 May 2020). Bottom: median percentage of change based on daily values (with reference to the data provider’s default baseline from the five-week period between 3 January and 6 February 2020) in visits to places like local parks, national parks, public beaches, marinas, dog parks, plazas and public gardens for the month of April 2020. Data are plotted for 900 subregions within 131 countries (note that for 1.6% of the subregions fewer than 5 daily values were available for April 2020). This information should be interpreted cautiously, and is shown here merely to provide a preliminary, coarse-scale illustration of some recent changes in human mobility; scientific analyses will require higher-resolution, calibrated data. Data sourced from ref. 16 (data accessed 7 May 2020). Both maps were drawn with the QGIS Geographic Information System (http://qgis.org), using freely available data (2018) for country borders from GADM (https://gadm.org) (data accessed 6 May 2020).