By Meghan Flores, Lisha Steinkoenig and Anthony Epperly
The number and type of animal remains found on a beach can be an indicator of many things. In an attempt to understand the reason that there is fluctuation in both the amounts of different types of animals and the amounts of animal remains found weekly, we came up with four possible explanations. Through deductive reasoning, we were able to narrow down our number of explanations to two.
The time span of our scientific experiment was two weeks. The first weeks recording date was October 2nd 1999. The second weeks recording date was 0ctober 9th 1999. Although we were conducting our experiment with the greatest amount of accuracy we were capable of, we were amateurs. To improve the accuracy of recording the number of each type of animal remains found in Crystal Cove State Park in the future, there are a few things which we overlooked that should be paid attention to. For example, the experiment would have more credence if each week we had timed the amount of time that we spent searching. Also, the quality of the project would have been enhanced if each week we measured and searched the exact same amount and area of space.
Despite the faults that we found in retrospect, we were able to rule out two possible explanations for the differences, and also find two possible explanations.
In the first week of observation at Crystal Cove State Park we began at point A, which was at the North end of the beach. The three of us walked in a slow and steady manner until we reached point B. Point B was Pelican Point. Anthony searched along the inter-tidal zone while Meghan and Leisha searched along the dry sand. The same approach was taken in both week one and week two. While the three of us walked down the beach we carried a notebook and a pen to record the data that we found. At the end of each week of searching, we would meet and organize our recorded data into charts. At the end of both weeks, the three of us combined all of the information and formed our tables and graphs.
Our results showed a large fluctuation in the amount of animal remains found on Crystal Cove State Beach between week one and week two. However, lobster sheds were the predominant animal remains found each week.
There were a total of fifteen animal remains found the first week. Eight if these remains were lobster sheds. The next most predominant animal remain found on the beach were crab sheds, which, there were three of. The two dead sea hares made this type of animal the third most predominant animal found. An individual starfish and an individual dead bird were the two other types of animals that we found on the sand of Crystal Cove State Park.
There were a total of only three animal remains found on week two. There were two lobster sheds found. The only other animal remain found was a single sea urchin.
According to our data, week 1 had more animal remains. Our group came up with four different possibilities to explain why week one had the majority of the animal remains. Two of the four possibilities were accurate with our experiment. We ruled out the other two possibilities because they did not match up with our outcome.
The first possibility that we came up with to account for our results was the difference between tides. Week one had a significantly higher tide than week two. Our group thought that week ones higher tide was a possible explanation for the weeks larger amount of animal remains found. However, we realized that the tides effect on our experiment was different than initially suspected. After careful analysis, we realized that the difference in tides made a difference in the amount of area that we searched. Week ones high tide made our search area much smaller than week twos low tide. The very low tide of week two left the inter-tidal zone exposed, and therefore the inter-tidal zone became part of our searching area. This expanded area was home to many living animals, but did not have any animal remains. The time that we took to search the inter-tidal zone took away from the time that we searched the dry sand. Since we spent less time searching the dry sand, where the animal remains are primarily found, we found less of the remains. As a result of our reasoning, the tides were ruled out, as an explanation for the change in amount of animal remains found.
Another possibility that we came up with to explain the change in the amount of animal remains found between week one and week two were the waves. Weeks one waves were rather small while week twos waves were rather large. We believe that, upon their entrance on to the sand, the high-energy waves of week two pushed things, such as rocks, on to the beach. However, upon their going back into the ocean, these high-powered waves may have pulled many things in with them, such as the animal remains. This explanation is very valid and is left as a possibility.
Pollution is one thing that we considered as an explanation for the fluctuation in the number of animal remains found between week one and week two. Our group observed a steady stream of water entering the ocean water of Crystal Cove State Park. This water was labeled as contaminated. We later found out that the water is filled with animal feces. This contaminated water left us wondering if there was a heavier stream in week one than in week two, resulting in a higher number of animal remains in week one than two. However, because it rained the day before week two, the contaminated water would have been flowing heavier on week two. This would have resulted in a larger number of remains found in week two. Since this explanation clearly did not match up with our data, we eliminated it.
In an attempt to understand the reason that week one had a larger number of animal remains, and also to understand why most of these remains were lobster sheds, we decided to consider a natural reason for this fluctuation. A large amount of lobster sheds does not necessarily mean that there are a large amount of dead lobsters, but can merely be a sign of a large amount of lobsters growing and shedding their outgrown shell. It is possible that lobsters mate at the same time of year, give birth at the same time of year, and that the young grow and shed at the same time of year. This opens the possibility that the reason that week one had more animal remains was because week one fell on the lobsters shedding time.
Garrison, Tom. Oceanography. 1998
|Table 1: Observations of Animal Remains Found at Crystal Cove State Park|
|Week One:||Week Two:|
|Animal:||Dead Sea Hare||2||0|