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Catalina Island Leadership Program

Phoenix Country Day School

Kelp Forest Information Links

Channel Islands National Marine Sanctuaries

Introduction:

The eighth grade class at PCDS recently went on a class trip. We went to Catalina Island, one of the Channel Islands, off the coast of California. We stayed at a camp, CELP which stands for Catalina Environmental Leadership Program, in Howland's Landing. We got there on October 15, spent an exciting week there, and left on October 19. The reason we went there were was to do research for our previously established science projects. Before we left for Catalina Island, all of the students proposed a topic that they wanted to research while we were there. Our question was, "Which species of dolphin live in the Channel Islands and why do they prefer that type of environment?" Once we got back, we decided it would be beneficial to refine our question adding; "Why didn't we see any dolphins while we were there?" because we expected to see at least some dolphins while we were there. Before our departure for Catalina, we acquired information about dolphins such as where they prefer to live and what living conditions they prefer, in order to be prepared for what we had to study while at the island.

Research:

There was a short list of items we had to research while we were at Catalina. There were a number different methods and materials that we used while researching. The most important thing we needed to investigate was whether the water near Catalina Island was right for the dolphins, so we kayaked and snorkled to find out. Nimra and I mainly did our research while we were kayaking as opposed to snorkeling. While kayaking, we sampled some of the water from the surface and put it into a test bottle. We then inserted a thermometer into the bottle and recorded, on waterproof paper, the temperature. We decided that it would also be good to assess the temperature further down in the ocean also, seeing as dolphins don't always stay on the surface. In order to get a water sample from deeper down in the ocean, we used a Van Doran bottle. We lowered it into the ocean, while holding onto it with a string, and collected water. After we raised the Van Doran bottle into our kayak, we put it into one of the test bottles, took the temperature, and recorded it. To get the depth of the water, we used a weighted line. By lowering the weight straight down into the water we would be able get an accurate measure of the depth. The line attached to the weight had markings that counted meters on it. We counted those markings as we raised it back up to determine how far we had lowered the line. The most interesting tool that Nimra and I used was the secchi disc, which we used to establish the turbidity level. We lowered the white plastic disc into the water and counted the meters on the string until we couldn't see it anymore. The water where we were during our first kayak was so incredibly clear that we were able to unrolled the string all the way and could still see the secchi disc at the bottom of the ocean. To know where we were when we recorded this data, we used GPS devices and plotted where we were. We then uploaded those points onto the computer we took with us to Catalina Island. The final substantial method we used to help with our research was photography. The combined use of these tools provided Nimra and I with results we could have confidence in.

At Catalina, Lauren and I discovered that dolphins were not living off the coast of this island at the time we went. Since dolphins were not at this particular island, we inquired as to what conditions dolphins have to live in and what types of environment they prefer to live in. Before we left for Catalina Island, we learned a lot about the five different species of dolphin that live in the Channel Islands. They five species are the Bottlenose Dolphin, the Common Dolphin, the Pacific White Sided Dolphin, the Killer Whale, and the Risso’s Dolphin. Before we went, Lauren and I researched the different species and found out the distribution, habitat, diet, and interesting facts about them. We took these facts to Catalina with us, and we were able to decipher why the dolphins were not there at this specific time. Through our research, we found out that these dolphins prefer to reside in 10-15E Celsius, tropical or temperate, nutrient rich waters. At the time our 8th grade class went to Catalina Island, it was approximately 17E Celsius and it was also a La Niña season. A La Niña season is when the ocean water temperature is unusually colder than normal. Lauren and I believe that the chilly temperature is one of the many factors that contributed to why the dolphins were not at the island. Additionally, these mammals are accustom to polar regions and the northeastern Pacific Ocean. Another reason we believe we did not see any dolphins is because of our location in relation to the island. During our snorkels and kayaks, we stayed relatively close to shore and the five types of dolphin we researched all opt for deeper, offshore waters. We had also learned about the diet of each of the dolphins. For the most part, the diet of each dolphin are the same. Their diets consist of fish, squid, shrimp, and octopus. Knowing the information about each of their diets beforehand, we assume that one of reasons these dolphins were not at the island was due to the lack of shrimp, squid and octopus where we were. In addition to all these other factors, we believe that since kelp is not part of a normal environment for dolphins, a kelp forest would not be a reasonable place to find dolphins. Our results showed neither Lauren nor I evidence of dolphins at this location during the week we were there.

Conclusion:

Lauren and I have concluded that there were no dolphins around the island at the time we went. We have assessed that there are primarily four reasons dolphins were not residing at Catalina Island during this time. One of the main reasons we did not see dolphins where we went was because we were too close to shore during the kayaks and snorkels. Secondarily, we did not see dolphins because it was much too cold due to the La Niña season and dolphins would not be able to survive at temperatures as cold as they were. Our CELP groups went snorkeling in an environment that was not suitable for any type of dolphin we researched, seeing that we were in a kelp forest. In addition to the previously mentioned factors, some of the food that dolphins eat such as squid, octopus, and shrimp are relatively scarce off the coast of Catalina where we were. These are the four main factors that combined to explain why dolphins were not found at Catalina. If Lauren and I were planning on furthering our research on dolphins, we would most likely not go back to Catalina Island. A more practical place to research dolphins would probably be the northern Channel Islands. However, the best place to go to study the environment and habitat of the Bottlenose Dolphin, the Pacific White Sided Dolphin, The Risso’s Dolphin, The Killer Whale and The Common Dolphin would be the Northeastern Pacific Ocean.