Year 2 (2024-25)

Several items of previous literature have shown evidence of a rise in ocean temperature anomalies of approximately 1.10 ± 0.12 degrees celsius since the 1970s, which have started to affect the migration behavior of large aquatic teleosts, such as sharks; namely, they are migrating approximately 14 days earlier than normal . This may be due to shifts in prey animal territory, shifts of preferred temperature ranges, and more. However, there is a lack of data on specific species of sharks and the specific areas they reside in. Therefore, the focus of this study was whether increases in ocean temperatures had an effect on the migratory behavior of sandbar sharks residing in the New York Bight, or the Atlantic side of Long Island, during the period 2018 - 2022. The alternative hypothesis stated that as ocean temperatures increase, sandbar sharks living in the New York Bight are migrating earlier in the year. The null hypothesis is that ocean temperature anomalies have no effect on shark migration. In conducting this study, a pre-collected dataset of 75 individual sharks’ immigration and emigration timing from 127 unique tag receiver locations in and around the New York Bight was used. A total of 6 scatter plots were created, including the relationship between years and days of migration, years and average days of migration, and years and average temperatures. These were analyzed using a Pearson’s correlation test. 10 histograms were created to demonstrate the spread of shark migration, and by extension, their individuality as organisms. 2 bar graphs were created to compare years and average migration days using a one-way ANOVA and Post-Hoc Tukey test. All steps beyond the pre-collecting of data were completed solely by the student researcher. It was found that New York Bight temperatures have decreased and New York Bight Sandbar Sharks have begun to migrate earlier in the year to a degree of statistical significance. Therefore, the alternative hypothesis that sharks begin to migrate earlier as ocean temperatures rise has been partially supported here. However, lower temperatures may be caused by changes in migrational preferences. This is crucial to the study of shark migration because it demonstrates a shift in where sharks will be at certain times of the year and a shift in their warm/cold periods of migration. Additionally, as sandbar sharks are a keystone species, without them, their ecosystems may collapse. In future research, the same methodology used in this paper may be employed; however, the dataset should rather be composed of the same amount and same tagged sharks for each year to lessen the chance of excluding outliers and the area of study should rather be their initial migration location. Future research may also start looking at migratory location patterns in order to have a better understanding of where sharks are present as their migratory timing shifts outside of its normal range. Other studies may track the effects of these migration anomalies on interactions between humans and sharks.