A study recently published in the journal PLOS ONE reveals 14 out of every 350 dolphins in the Indian River Lagoon died of asphyxiation between 1997 and 2011. While the number might be small, it holds greater implications for the survival of the dolphin population in that area.
The lagoon covers about 40 percent of Florida's coastline and is the home of several bottlenose dolphins, as well as a plethora of other species. In fact, it is the world's most biologically diverse estuary, the dolphins who call it home never leave and thus, are greatly impacted by any changes in the environment and need to be carefully monitored.
According to the study, dolphins choked on fish as well as fishing hooks and line. The creatures would eat the fish and the hooks and line would already be embedded in the fish's body causing the dolphin to asphyxiate.
While the involvement of fishing equipment points to a human problem threatening the dolphins, but the study also shows invasive species as a threat as well. Discovery News explains the dolphins cannot swallow fish with strong dorsal spines because they risk choking on them.
Lionfish are beginning to invade the lagoon and pose a bigger and bigger threat as the dolphins eat and choke on them. Lionfish are a capable of populating and invading a new area rather quickly. This is concerning scientists who fear, over time as the number of lionfish goes up, the number of dolphins in the lagoon will go down.
Scientists at Sea World and the Hubbs-SeaWorld Research Institutie conducted the study. In a press release from the organization, Megan Stolen explained how the study lays the groundwork for future research. SeaWorld's Judy St. Leger has said, over the next year, the Institute's research will focus on investigating and defining all of the significant causes of death for dolphins in the lagoon.
