I propose a bioblitz during the hackathon as a preparation for a session on feeding wikimedia platforms with iNaturalist content and vice versa.I was told that close to the venue there is a nature reserve Divoka Sarka: https://en.wikipedia.org/wiki/Divok%C3%A1_%C5%A0%C3%A1rka which might provide a nice place for a bioblitz.
If you want to join, bring your smartphone or/and camera. The ideal camera captures the GPS location as metadata, either through built-in GPS or some link between your phone and your camera. Although handy, not really necessary. The picture used in the Wikipedia article on Acanthoderes rubripes was made with a "not so recent" smartphone.

We will leave the library and try to find a nice spot in the nature reserve and try to observe as much as possible. After uploading those pictures to iNaturalist we can leave observations for scrutiny by the iNaturalist community and continue the next day to add/include the observation that gained research-grade (or other metric) in to Wikipedia, Commons an Wikidata. An observation gaines "research-grade" status if there is consensus indicating some level of quality.