Glad you had a good holiday.
I haven't dived there, but if it is anything like Tenerife, the marine life is not particularly abundant, but the topography can be fairly spectacular.
Personally, i would have been appalled to see hammerheads at the supermarket. Although the locals eat them, they are in decline. All sharks (well, all the big ones!) breed late and slow. If they continue to be taken fromt he sea at the current rate, they will disappear from our oceans. The hammerhead is one which is seen in far fewer numbers than it used to be. Yes, it is in decline.
Should we do anythign about it? I think it depends on how they are caught and whether education of those who fish for it and eat it will persuade them to preservation or conservation. Limiting catch numbers can help in areas where there is a tradition of eating certain seafood.
I don't know if the fact that locals eating them means that they are in the local seas, but development of an ecotourism might raise awareness both of tourists, fishermen and locals. How many visitors come back from holiday having eaten a 'local delicacy'.
Food for thought
