Perhaps the most mysterious cetaceans we see here are the beaked whales. Most frequently these involve just brief sightings, usually of either Northern bottlenose whales Hyperoodon ampullatus or Sowerby's beaked whales Mesoplodon bidens as they surface a few times and pass by. Although the most regularly encountered beaked whale in the North Atlantic the Sowerby's beaked whale is especially hard to see well (but see below). We know remarkably little about these animals. Most of what we know has been derived from examining dead specimens stranded or washed ashore. We know they are capable divers and can remain submerged for up to 30 minutes in search of their preferred prey - deep water squid and fish - but next to nothing is known of their social behaviour.
A female Sowerby's beaked whale spy hops to take a quick look at our boat and its amazed crew and clientele.
A couple of days ago we encountered several mixed sex groups of Sowerby's in the deep water south of Ribeiras (see above). The groups did not show typical behaviour and appeared to surface fairly synchrously in a circular pattern with some individuals swimming clockwise and others counter-clockwise, all in tight formation. I have never seen this behaviour before and frustratingly I have found no reference to this behaviour elsewhere. So what was going on? Was this social/sexual behaviour or cooperative feeding behaviour? Who knows? All I can say is that all those who witnessed it agreed it was truly an amazing glimpse into one aspect of their mysterious lives.
Sowerby's often surface to breathe at a steep angle 'beak first' (see above). This and the position of the male's tusk along the lower jaw (see below) are diagnostics features of the animal that can be used to identify them at sea.
The males possess distinctive tusks on their lower jaws (see above) but otherwise both sexes are toothless. Judging by the distinctive scars on their bodies the tusks are not infrequently used during social interactions (see below).
In the photo above a male Sowerby's arches his back before submerging and reveals his heavily scarred body. The straight scars are almost certainly inflicted by other males but the cause of the other odd circular scars is less obvious. Perhaps they were caused by Lampreys, Cookie cutter sharks or species of squid it was trying to prey upon.
When we go to sea our trips are not just to see whale and dolphins, they are also trips into the open ocean in search of whatever else we may encounter. Not infrequently we find sea turtles, especially the Loggerhead turtle Caretta caretta (see below). These hatch out from their nurseries on the sandy beaches of south-eastern USA or the Caribbean to spend their lives drifting around the Sargasso sea, often passing the Azores. Only the females return to shore and then only to lay their eggs, usually very close to the place they were hatched.
