Boat Trip 10/18

It was a semi-calm day when we set out to sea in the panga on the 18th of October. We passed pelicans and terns as we were nearing Isla Datil. As we approached Isla Dalti we saw a pod of approximately 10-15 Common Bottle-nose Dolphin. We soon came upon of a flock of Booby’s foraging in the rich trench between Isla Tiburon and San Esteban. The currents in the trench are a vital part of the marine ecosystem because it creates an incredible upwelling of nutrients that attract many fish, such as sardines, anchovies and herring to come to the surface to forage. Below the diving birds were Long-beaked Common Dolphins that were taking advantage of the abundance of Chanidae and Clupidae. We estimated 200 dolphins on the surface and another 200 plus dolphins submerged. The Long-beaked dolphin seemed inquisitive of the boat and would come dangerously close. Fortunately, their accuracy is phenomenal and they know when to split from the boat. They played in the wake and along the sides of the boats gunnels, jumping in and out of the water. The experience attracted us for over an hour, and by then winds had picked up. We had another forty minutes ahead of us to reach our destination. The Panga bounced vigorously through the white caps and 25 knots winds. We had to abort our mission to San Esteban and find a safe place to snorkel closer to the mainland. We decided to visit Isla Tiburon. It was less windy and the current wasn’t so strong because of the inlet. We snorkeled for about an hour. We identified around 35 species of fish. Some classmates got the privilege to spot a Black Sea Turtle which is closely related to the green. By looking at pictures, I would estimate the turtle to be around 4 years of age and approximately 25 pounds. After we snorkeled Cosme’s, excellent trained eye captured an octopus to share with the class. The ride back was intense. I felt like I was once again doing my rescue diving in the Florida Keys during hurricane season. Everybody has a sore back or knees and we all got completely soaked. But, that is what you pay if you want to be marine biologist.

For the people that are interested in marine mammals I will distinguish between the two species that were identified today:

Common Bottlenose Dolphins are the most well known dolphins to humans. They are the most abundant dolphins seen in aquariums and other sort of attractions. Flipper was also a CBD (Common Bottlenose Dolphin) I’m sure everybody has a slight understanding of their characteristics. To get into more detail, there is variability between inshore CBD and offshore CBD. Off shore dolphins tend to be larger and also darker; the inshore dolphins are slightly smaller in size and lighter in color. Both however have wide heads and body along with a shorter beak when compared to other species. They also have counter shading characteristics (darker on top, lighter on bottom). This could be for camouflaging. When they are on the surface the light belly blends in with the sky, and when they are near the bottom, they tend to blend in with the ocean floor. That’s a quick and easy way to explain it. The CBD are cosmopolitan species that occur in oceans and peripheral seas at tropical and temperate latitudes (Pieter Folkens, 2002). They often favor coastal areas such as islands, atolls, bays, and estuaries. However, there is also a pelagic population that live far off shore.

The Long-beaked Common Dolphin
This Species has a variety of characteristics throughout different populations from variations of skull size, body size and fin size. They are smaller than the CBD weighing about 330 pounds. It is named after its long beak They display a great example of counter shading. The upper portion of the body is dark gray to black, with dark flippers. The LCD are typically found in near shore tropical and warm environments. They have been spotted all over the world such as, Venezuela, Argentina, west coast of Africa, etc

Yes, and if you are wondering what the red stuff floating around the water is, well, that would be the red tide.