The tan color on this map shows the range of sperm whales in the Gulf of Mexico. The colored areas show the chance of sperm whales utilizing this habitat, with red being the highest.

Not quite a new species, but the population of sperm whales in the Gulf is distinctly different from their relatives. So different that last week, in response to a petition from WildEarth Guardians, the National Marine Fisheries Service announced that it will be taking a closer look at sperm whales in the Gulf of Mexico in order to determine if they should be protected under the Endangered Species Act. Sperm whales across the world are already listed as an endangered species, but this new designation will recognize the Gulf population as a distinct group and protect and monitor it separately from the global population.

There are characteristics of sperm whales in the Gulf that may be sufficient to classify them as a distinct group. Gulf sperm whales do not leave the Gulf and are generally smaller and use  different vocalizations (probably learned culturally) than other sperm whales. Gulf sperm whales also face Gulf-specific threats such as oil and gas development, high levels of shipping traffic and noise, potential effects from the BP Deepwater Horizon oil spill, and water quality degradation near the mouth of the Mississippi River. As shown on the map above, the area southeast of the Mississippi River Delta is important for sperm whales. The outflow of nutrients from the river, upwelling along the continental slope and eddies from Gulf currents create unique ecological conditions that make this a productive area where sperm whales go to find food and potentially mates.

We do not know whether the population of sperm whales in the Gulf is growing or declining, or how many human-caused deaths of sperm whales happen in the Gulf. In order to improve our understanding of this amazing species, which is so dependent on the Gulf, we need more long-term research and monitoring. One way to gather information about sperm whales, and other marine mammals, is through tagging and tracking of the animals. Using satellite-linked tags and radio transmitters attached to animals can provide information on habitat use, foraging behavior, distribution and exposure to hydrocarbons. Ocean Conservancy is working to enhance marine mammal tracking and tagging research in the Gulf. We are proposing that some restoration funding from the BP Deepwater Horizon oil spill be allocated to tracking and tagging research for marine animals in the Gulf to increase our understanding of these animals and their threats.

Tagging and tracking wildlife over time will put scientists in a much stronger position to learn whether or where changes are happening in the Gulf, and to make sure we are on the right course to recovering from the nation’s largest offshore environmental crisis.