What is special about this year’s dolphin stranding?

Some scientists are trying to solve a mystery on Cape Cod. Dolphins have been getting stranded there. It’s not completely unusual. There are typically around 120 strandings per year. (6) But more than 100 dolphins have gotten stranded in the first month of this year. Sometimes they’re washing 10 at a time.
    At least 81 of these dolphins were either found dead or died shortly after being discovered. One animal welfare group director called the number "disturbing". Now, no one’s certain what’s causing the dolphin deaths.
    A local harbor master says changes in water temperature could be a contributing factor. Usually the Cape Cod harbor ices over in winter, so dolphins don’t get close to the shore. But the harbor master says now that the water’s warmer, more dolphins are showing up than ever before.
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