Can we mark gobies for lab and field investigations?

In behavioural work, marking techniques that allow individual identification during observations have proven highly valuable. This applies in particular to studies in the wild, but also to lab settings involving more than a few individuals. However, individual marking of gobies for visual identification is hampered by several problems including hydrodynamic effects, increased infection risk, ongrowth on external markings and difficulties with reliable recording of the marks, many of which are made worse by the gobies’ small size. What techniques offer the best compromise between observability, ease of use, and minimal harm to the fish? Participants are invited to contribute their experience and viewpoints on the pros and cons of various techniques, including fin clipping, external markers attached with line through fins or integument, ink tattooing, coloured elastomers, pit tags, and natural individual markings. The aim is to develop easy-to-use and reliable marking techniques that would work well across species.