In today’s Academic Minute, Dr. Stan Kuczaj of the University of Southern Mississippi explains the relationship between Hurricane Katrina and the dolphin population along the Gulf Coast.
Stan Kuczaj is a professor of experimental psychology and Director of the Marine Mammal Behavior and Cognition Lab at the University of Southern Mississippi. His lab conducts research on the behavioral and cognitive abilities of marine mammals such as bottlenose dolphins, sperm whales, beaked whales, killer whales, rough toothed dolphins, and walruses. He holds a Ph.D. from the University of Minnesota.
Dr. Stan Kuczaj – Hurricane Katrina and Dolphin Populations
We have been studying the dolphin population in the Mississippi Sound for a number of years. In 2007, we noticed a significant increase in the number of dolphin calves, and suspected that Hurricane Katrina, which decimated the Gulf Coast of Mississippi in August of 2005, had something to do with this increase in successful dolphin births.
We knew that there were many more strandings of live and dead juvenile dolphins immediately following Hurricane Katrina than normally occurred, suggesting that the young dolphins had been separated from their mothers during the storm. The fact that many dolphin mothers lost their calves during Hurricane Katrina resulted in a dramatic increase in the number of receptive females in this area that were available for mating, the resulting pregnancies producing the significant increase in calves in 2007.
But an increase in viable females would not result in an increased number of successful births unless there were adequate resources to support the pregnant females. Hurricane Katrina destroyed most of the commercial and recreational boats in the Mississippi Sound and surrounding area, which resulted in two benefits for the dolphins. First, the lack of fishing vessels meant less competition for fish, and likely made fish more readily available to the dolphins. Second, we know that the presence of boats, especially high-speed boats, disturbs dolphin foraging and socializing. Thus, the absence of boats in general allowed dolphins to spend less time avoiding boats and more time socializing and foraging.
All of these factors produced the perfect storm for dolphin well-being and reproductive success in the years immediately following Hurricane Katrina, the result being the increase in the number of dolphin calves that occurred in 2007.