A whale long known to inhabit the Gulf of Mexico and believed since 1965 to be a subspecies of the Bryde’s whale has been identified as a separate species.
Scientists supported the identification with genetic data on the animals collected since 2008 and analysis of a skull from a whale that stranded in Florida in 2019. They propose naming it Rice’s whale (Balaenoptera ricei) after marine biologist Dale Rice, who first confirmed the presence of these animals in the Gulf. Pending acceptance of that name by the Society for Marine Mammalogy Committee on Taxonomy, they call it the Gulf of Mexico Bryde’s (pronounced “broo-duhs”) whale.
“It is amazing that in this day and age, we are still discovering new species,” says Christian Wagley, coastal organizer with the New Orleans-based nonprofit Healthy Gulf.
Growing up to 42 feet long and weighing as much as 30 tons (five times heavier than an elephant), the new species is a filter-feeding baleen whale but, uniquely, one that dives deep and feeds near the seabed. Exactly what it feeds on remains a mystery.
These whales currently congregate in deep waters in the northeastern Gulf, but Wagley points out that is likely due to human activity elsewhere in the sea. One was confirmed off the central coast of Texas in 2018, and sound recordings have indicated their presence near the Flower Garden Banks National Marine Sanctuary, 100 miles offshore from Galveston.
Whales play important roles in marine ecosystems, cycling nutrients from deep waters into shallow waters and across long distances. Research shows this can increase marine productivity and support robust fisheries. These huge animals also strike a chord with people.
“Even though most people will never see one, they care about them and think we should preserve and protect them,” Wagley says.
Previously listed as an endangered subspecies of the Bryde’s whale, the new species retains Endangered Species Act protection. The National Oceanic and Atmospheric Administration estimates that fewer than 50 individuals remain, making these whales one of the rarest animals on the planet.
Close to 20 percent of the population may have died as a result of the Deepwater Horizon spill, and oil and gas exploration and production remain a major threat. These whales also face risk from vessel strikes, underwater noise pollution, entanglement in fishing gear and marine debris (the 2019 stranded whale died from plastic blocking its digestive tract). Proposed offshore aquaculture could create a new threat.
To protect this new species, scientists say that aquaculture, offshore wind farms, and other new industries need to be placed outside of its known habitat. Measures needed to reduce the risk of collision with vessels include speed limits when transiting the whales’ habitat and limits on ship traffic in habitat areas at night when the whales rest close to the ocean surface.