Dolphin Tales: Dolphins, sharks and hurricanes
Hurricanes spend most of their time out at sea. If you count the loss of coral reefs and other marine life, this is also where the hurricanes do most of their damage. Fortunately, dolphins are able to sense approaching storms and can get out of the path of danger. Sharks also have an innate response to extreme weather. Both species are fast swimmers and this gives them an edge.
Dolphins sense changes in weather based on how much salt is in the water around them. Hurricanes dump a lot of fresh water in the ocean due to rain and this reduces the salinity of the water at the surface. Dolphins respond to this change by fleeing to deeper waters of the ocean. Unlike sharks, dolphins still need to surface to breathe every 10-15 minutes and this can get a bit rough.
Sharks, on the other hand, sense a change in barometric pressure causing them to flee to deeper waters. Sharks have organs called lateral lines that are similar to a human’s inner ear. These long fluid filled tubes are very sensitive to vibrations in the water. This is how sharks can hear the thrashing of injured prey through thousands of feet of water.
As the hurricane force winds move over our shallow waters, the water underneath the surface moves back and forth over the seafloor. These rapid motions stir up the sediment and also deprive the water of oxygen. Sand, shells, sea grass and debris go flying. Territorial fish that are unwilling to abandon their claim don’t fair well. Their gills get clogged with debris and they get battered. Slow moving sea life like seahorses and starfish don’t stand a chance. It can take months or years for the ocean to recover.
Capt. Cathy Eagle has spent over 40 years boating in our local waters. As a professional charter captain she specializes in dolphin and nature tours. Visit CaptainCathy.com or call 239 994-2572.