Whilst the breakthroughs in satellite tracking have given us a much clearer understanding of basking shark movements and feeding behaviour understanding the size of the European – Atlantic basking shark population remains a huge challenge. This is an interesting paper because it uses mark – recapture approaches to assess the size of basking shark populations. Mark – recapture has been a well-established way of measuring population size for over fifty years. With more projects using photo id and other techniques to identify individual animals this technique can be applied but its success will depend on many factors. Click here to read more.