LEWES, Del. -- Experts say an unusually high number of bottlenose dolphin carcasses have washed up on Delaware's shores over the last few weeks.The MERR Institute's Suzanne Thurman tells The News Journal that the sightings span the length of the state, which usually sees about five reported dolphin deaths at this point in the year.She says the marine mammal protection organization hasn't been able to glean information on what's causing the dolphin deaths, as the bodies arrive so decomposed.The National Oceanic and Atmospheric Administration had recorded an elevated number of bottlenose dolphin deaths in the mid-Atlantic since 2013, attributed to a terminal virus. Thurman says she doesn't think this year's deaths were caused by the virus, as it usually follows a 25-year cycle.------