Sperm Whale Seismic Study (SWSS)

Summer Breeze Daily Reports - July 26, 2005

Position on 07/25/2005, 26 52N 927W

It’s four in the morning, and I’ve just come on watch. Its so calm, and the team before me did such a good job of tracking the whales at night, that I can hear a pair blowing off to starboard, just out of sight under a weak moon. I need to get this written now because (hopefully) once first light comes we will be very busy again.

We worked with out big group through the day yesterday. Often these groups are so dispersed that it can take a few days to get good data from most of the individuals, and it won’t be until we analyses the photo-id images that we have a good idea of how many animals there really are here. This group has quite a few calves in a variety of sizes, ranging from very small to animals that look almost as large as an adult, but show typical suckling behavior. Smaller calves don’t perform long dives, they stay closer to the surface and seem to track the adults through dives. One of the calves today was quire well-marked; it had a cookie cutter shark bite on its right flank. This allowed us to see that this particular individual swam with, and behaved as though suckling from, three different adults at the surface! Of course, we don’t know that it was successfully taking milk on all of these occasions, but this does emphasize that assessing the number of calves and their “mothers” might not be straight forward. Although we had a long day of photo-id we weren’t convinced that we had all the animals covered yet so we decided to track the group through the night.

Through the day we heard that Raul has been making a good recovery and, although his foot is still swollen and painful, the doctors have given him the all clear to rejoin the boat. This presents us with a dilemma, we want him back and we should work more effectively with a full team, but we can’t waste this good weather. Stacie has researched a variety of options but we will put off making a decision about exactly what to do until we reach the Canyon area. If nothing else, by then we may be running low on fuel so a brief port stop will allow us to refuel too.