Very informative graphic novel about sharks. Not sure what age range this is aimed at, my guess is middle-grade, although some of the vocabulary might be a little challenging for kids. The art is good and all salient points are covered.
According to the Internet Bernard Séret is a retired French marine biologist, more specifically an ichthyologist specializing in sharks and rays, of which he has discovered several species. I am pretty sure that he is the grey haired narrator of this.