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What's New! Ocean Matters Dolphin Strandings: Reasons and How We Can Help Dolphin Strandings Dolphin strandings are one of the strangest and unfortunate occurrences that we see in the oceans. For most people, observing a stranded dolphin is not easily forgotten. Scientists still do not know exactly why dolphins strand themselves but they are getting closer to understanding. We look at the potential reasons why dolphins strand themselves and what people can do to help. Reasons Why Dolphins Strand Themselves Sometimes a stranded dolphin may have died at sea due to natural causes and then washes up on shore. Determining whether a dolphin died on the beach or in the oceans can be difficult as ocean water can preserve dead bodies for sometime. There are many reasons why a dolphin may accidentally or deliberately strand itself onto a beach. Many strandings are caused by injuries sustained by the animals. Off the coast of New England, in the United States, dolphins have been observed to strand themselves with visible damage from interactions with fishing nets. Sometimes the stranded dolphins will still have pieces of the nets clinging to their bodies. Fishing nets are one of the most dangerous things that dolphins can run into in the open ocean. These nets can and often do cause the deaths of other large marine mammals such as whales and they also are responsible for killing sharks. Other Reasons for Dolphin Strandings Other reasons for dolphin strandings include inner ear parasites that can disrupt the dolphins' sense of balance and possibly even their sonar abilities. If this happens a dolphin may become confused, disoriented and accidentally swim onto the beach. Scientists have interpreted mass strandings as akin to dolphin suicide, but there is little evidence to back this theory up. There is also a lot of evidence linking underwater noise and military sonar testing with dolphin and other marine mammal strandings. It is also possible that sick and unwell dolphin school leaders will accidentally lead a pack of dolphins onto the beach. One quite interesting stranding theory involves the Earth's magnetic field. Magnetic Navigation Corridors Cause Strandings? There is mounting evidence that dolphins use the Earth's magnetic field as a form of navigation in the open ocean waters. More precisely the theory states that dolphins are following disruptions in the magnetic field as navigation corridors. The strandings occur in areas of low magnetic field density where the navigation corridors intersect land at right angles. The theory states that dolphins follow these magnetic corridors and plough onto land thinking it is where they want to go. In areas where the corridors followed the coastline fewer strandings occurred. Although this is still a theory, there is mounting evidence of similar abilities in birds, fish and reptile species. As time progresses there will be more scientific resources devoted to this interesting theory. Helping a stranded dolphin can take on many different aspects. If we find a stranded dolphin on the beach we should note the species if possible, the location and report it authorities such as the Coast Guard. If the dolphin is still alive on the beach, we should try to keep the animal cool and wet while avoiding getting any water into the blowhole. If it is not possible to keep a stranded dolphin wet it will likely die from overheating. Even if we manage to keep a stranded dolphin cool and wet it may not be possible to return it to the wild. In some cases the dolphin may be put down to minimize any suffering. In any event, stranded dolphins that are successfully returned to the oceans are rarely outfitted with radio tracking collars. Without radio collars scientists know little about how these dolphins fare once they are returned to the oceans.
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