Our first trip out to find and observe dolphins was a huge success!!
We left port at 6:56AM and headed counter clockwise around the island (check out the map of Mikura to orient yourself to the places I mention.). Hishii-san drove for Manpu and I – this was a research trip with no guests. The owner of the boat, Gen-san, donated its use to us this morning since he did not need to use his boat till about 10 AM.
Our first group (4 dolphins) were seen not more than 200 m into our trip. Easy to see on a sea that was flat calm with only a slight breeze. Our second entry with this group brought us near to Shirataki. In all the places we observed dolphins today the underwater visibility was not great (2-3 meters and 'silty'). But near to Shirataki, the waterfall, the water was also cold! or at least felt colder than other spots. Average temp was 20°C — and for those of you who don't know, I am a cold whimp! 🙂 (Too much time in the warm tropical Sargasso Sea!)
Our largest group seen was south of Mikura at Osauwa. A spread group of about 40-50 animals. On several entries to observe the dolphins, Manpu and I saw about 30 or more in smaller, tighter sub-groups. Twice there were three individual female sub-adult dolphins that were playful. They consistently swam back around to Manpu and me when we thought they had moved off. They were clicking and head scanning at us and alternately surfing the slight swell in the surge zone.
A group of 4-5 males circled Manpu a few times on one entry that I sat out and observed from the surface. They seemed truly interested but were also socializing among themselves.
The last group we observed from underwater had at least two mother/calf pairs in it. The visibility was worse in this area and the dolphins were not at all interested in us. Manpu got in first, but the group was of subadult males. The second entry was by me and I saw the group with the two moms and calves. One calf still had fetal folds! These fold are vertical on the calf's body and are from being 'folded up' inside mom before birth. They folds usually disappear after 3-4 weeks of age … so this calf was likely less than 2 weeks old! There was another small animal … no folds though. But this might have been the calf Manpu saw in early May with adult female #080. When we confirm that this is a second new calf for 2000 (from video I shot), I'll post an update.
Though my data sheets are completed for this trip (which saw us back at the port at 9:31 AM), I still need to sort through the video I shot. That's when the ID's are made (if not while in the water) and the behavioral analyses come from. … I must admit, it is nice to have more data to work with!