Connecting The Dots Project
Scientists Uncover Highly Probable Causes of Shrinking Arctic Ice and Gray Whale Mass Die-Offs
Climate change is affecting various ecosystems, especially with polar regions experiencing some of the most rapid changes. These changes have significant impacts on species and ecosystems, including even the largest animals on the planet.
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Gray whales are large marine mammals known for their lengthy migrations. They travel from warm wintering areas in Mexico to Arctic feeding grounds. Adult gray whales typically measure between 40 to 50 feet in length and can weigh between 30 to 40 tons. Over the years, more than 2,000 gray whales have been found dead off the Pacific coast in three unexplained mass die-off events. The most recent and ongoing mass die-off began in 2019 and has claimed the lives of 688 whales and counting. While the gray whale population had rebounded to around 25,000 individuals at its peak, it now stands at 14,500 and is declining due to these die-offs and diminishing birth rates.
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Climate change is causing the ice sheets in the Arctic to melt 4x faster, which is altering oceanic currents, warming water temperatures, and potentially changing the food supply for whales and other creatures. New research suggests that these unusual mortality events may be linked to shrinking Arctic ice, which has led to a decline in the whales' preferred food: coastal small crustaceans called amphipods. The shortage of food sources triggered by the deterioration of the ecosystem is likely to have caused thousands of gray whales to starve to death. In fact, major mortality events among gray whales coincide with periods of low prey biomass and restricted access to feeding areas. Also, any resulting changes in prey distribution could lead to changes in foraging behavior, nutritional stress, and diminished reproduction for gray whales. Additionally, changing water temperature and currents could impact the timing of environmental cues important for navigation and migration.
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The research on gray whales in the Arctic sheds light on the intricate relationship between environmental conditions, prey availability, and the dynamics of even long-lived, highly mobile species.
Sources: https://oregoncapitalchronicle.com/.../unusual-deaths.../....