Costa Rica 2023
Field Work
What started off as a slow start on the Puerto Dulce looking for our first encounter with a Pan American Spotted Dolphin, erupted into a cheer for a second encounter with a humpback whale and her less than 1 month old calf. With a port water temperature of 31 degree C, overcast skies, minimal white caps (level 3) and the coolest day yet, team Earthwatch was wowed once again by the beauty and grace of the surfacing and submerging calf and cow. Per Dr. Lenin, the mom was relaxed in our presence due to the lack of air vapor from her blow hole, a common sign of stress. We spent over an hour tracking the whales behaviors, taking environmental readings and breaking to enjoy a few snacks including our daily watermelon treat.
DAY 6
Marc "Leaf" Abelson
Mangroves
Later in the day, we had a great lecture by Pedro, a local tour guide, about the ecology of mangroves and their importance to the health of the gulf and the surrounding environment. We discussed the benefits of mangroves and the problems they face and learned about the different species found in the Osa peninsula. Pedro detailed some of the unique parts and functions of the mangrove. For example, the plants have specialized parts on both their stems and/or leaves called lenticell glands which have the ability to extract freshwater from the seawater as well as to help filter out toxins from the water.
After the lecture, we took a short tour of the mangroves at our site and Pedro pointed out three different species of mangrove plants. He also showed us how the seed pods germinate while still on the tree, increasing their chance of survival. Once dropping, they have a head start to quickly start forming a new plant in the mud or, if during high tide, the seedlings can move with the tide and start growing along another part of the shore. Pedro also pointed out to us how one of the mangrove species have modified their root system, whereby hundreds of pencil-like roots shoot out from the ground like little snorkels, called pneumatophores, allowing for more surface area for Lenticell glands to take in oxygen and filter out the salt water and toxins.
Lecture
Later, we met with the PI, Dr. Lenin, for a discussion on dolphin reproduction. We discussed the importance of how a dolphin’s energy must be invested towards getting more energy and that male adults are sexually mature at 10 years of age and female dolphins at seven years of age with a 12 month gestation period. Dr. Lenin also discussed how bottlenose dolphins have inshore habitats which can be greatly affected by humans versus the Pan-American spotted dolphin which habitate deeper waters. This was an important point that was touched upon again later in the week when we discussed many of the effects of agricultural chemical runoff into the gulf, which appears to affect the ability of a dolphins immune system to fight the growth of fungal infections on their exterior. The fungus appears to affect bottlenose dolphins more due to their habitat, being closer to chemical runoff areas. One interesting fun fact we learned was that dolphins seem to synchronize pregnancies in order to have their calves at similar times of the year.
Photo of the Day
Quote of the Day
“I’ve been allergic to corn all week.” Laura, (always allergic to corn)
Reflection
Sitting on the boat for only a few hours today, led me to reflect on the focus and drive of the lead scientist and his team and how they have dedicated a significant portion of their lives to the preservation and livelihood of whales and dolphins and the general ecology of the Osa peninsula. This team understood that they had to use scientific science to inform conservation to sustain the critical habitat of the Osa peninsula through obtaining a Marine Protected Habitat. This task, particularly with their limited resources, seems Herculean, as they have worked for several decades researching the population, demography and behavior of dolphins and whales in order to have enough data to make the case for the protection and preservation. It has been truly inspiring for me to see the dedication towards their goals and I was proud to be a very small part of the research.
Video of the Day
