Continued from yesterday… Sperm whales dive the longest and deepest of all the whale species, going down between 1.3 km deep and staying down about an hour. The longest recorded dive is 2 hours and 40 minutes. They will come back up for about 20 minutes to re-oxygenate their blood, then dive back down to continue hunting. There is no light that deep, so have an amazing sonar system to find food. They primarily eat squid, and have the most powerful sonar system of any animal. Males can reach up to 60 feet and 125,000 lbs. (18m and 60 m tones). Females are ½ the length and 1/3 of the weight of males. Babies are about 13 feet and 2200 lbs (4m and 1 m tonne) at birth. Sperm whales live between 50 and 70 years and can be found just about everywhere in the world with waters deeper than 3,000 feet (1,000m).

Female sperm whales travel in groups, along with their calves, and live in tropical or sub-tropical waters all year. A female sperm whale starts breeding at about 12 and continues to breed into her 40’s. She has an 18 month gestation period. When her calf is around two years old, she will breed again, so each female has about one baby every 4 years or so, delivering about 10 calves in her lifetime. The babies can’t stay underwater for very long, so one female at a time will stay on the surface with the baby as the others hunt for food. When the whales sleep on the surface, they make a ring with their heads in the center and their tail fins out. They put baby in middle, and thus are able to shoo off any potential predators with their fins.

The male whales migrate away when they are between 6 and 9 years old. They are not exactly sure where the males go, but it is almost certainly to colder waters up north, and possibly even the Arctic Circle. After being gone for 15 years, the males come back to tropical waters to mate. They meet up with a female for a season, then move on again. Part of his research is on the whale cultural groups. Whales have distinctive cultural groups with learned behavior patterns and dialects, just like humans. And, like humans, they communicate primarily via sounds. The whales instinctively know not to mate with someone who speaks their own dialect. It is nature’s way of preventing inbreeding.

And why are they called sperm whales? The whales have Continue reading →

Today we went to Roseau, the capital city on the southwest side of the island, to go whale watching. Around Dominica there are sperm whales in the water all year. One particular whale watch company has a 90% success rate in spotting them. So, we decided it was worth the money. We headed to shore in the early morning. The tour wasn’t until 1330, but we had no idea how long it would take to get to Roseau, and we figured we could get some sightseeing in before the whale watch.

We are sad to admit this, but we have been here for 5 days now and have not explored Portsmouth yet. That is so out of character for us. Usually, the first thing we do after pulling into a new port is check out the town. We mentioned that there are three restaurants with dinghy docks. All are on the northern end of town, so when we have gone to shore to eat, we stayed to the north, and it was usually dark, so we didn’t see much.

The beach here is black sand. We walked beyond the beach and out to the road, heading south toward the town center. The road paralleling the shore is probably the main drag. It is lined with buildings, most small bungalows. Some are in good shape, some are dilapidated, and most are weather beaten but habitable. It looks to us like the individual lots tend to have several buildings crammed on them.

It is only a few blocks walk to the heart of town. The ambiance changed palpably. The buildings became more commercial looking, closer together, and better maintained (though most still looked like they could use a coat of paint and a little general work).

The bus stop is just north of Indian River. It was a parking lot with several nice mini-vans just like the one Winston was driving. We walked up and Continue reading →