Researchers have found more than 1,000 bottlenose dolphins in the Potomac River – an area that was once so badly polluted it was called a ‘national disgrace’ by President Lyndon B. Johnson. The 405 mile-long body of water that travels from the Potomac Highlands to Chesapeake Bay is a home to the marine mammals despite beliefs it still may not be safe for humans to swim in. Scientist first spotted around 200 individual dolphins in 2015 and since then have not been able to keep up with their numbers, according to the Washington Post.The Potomac-Chesapeake Dolphin Project have even witnessed one of the dolphin’s giving birth, an observation rarely seen outside of captivity, which is believed to be the third ever documented. Researchers were surprised to find that more than 1,000 bottlenose dolphins dwell in the Potomac River – it is quickly becoming an important area for research of the species They initially noted around 200 of the dolphins in 2015, since then they have tallied way more than 1,000 and have named 600 of them after political and historical figures Researchers are using the area to study the behaviors of these under-researched creaturesAnn-Marie Jacoby, co-director of the project said: ‘There are dolphins here, and there’s breeding and birthing going on, and this is connected to DC – such a populated, urban area.’You follow it further down and there’s all this wildlife here. And what people are doing up there, it does affect wildlife. They are directly linked to this oasis.’She and a team of researchers have been scanning the Potomac with an 18-foot skiff that serves as their personal research vessel.The presence of the creatures may be a sign that the waters in the Potomac are becoming cleaner. This suggestion was supported by the river receiving a B grade for water health in 2018, ten years before it had a D.The pollution of the Potomac was believed to stem from a series of issues including run-off water carrying pesticides and plastics into the river.Additionally strong storms damaged drainage and sewage pipes in and around the area that fed into the river, WTOP reported. The Clean Rivers Project aimed to help resolve the issue and so far has made a big impact towards improved the health of the river.This change has encouraged an increase in fish and wildlife, including the American shad and bald eagles returning to the area. Bottlenose dolphins were not known to dwell in the waters apart from a few odd sightings in the early 1900s and other accounts of ‘porpoises’ in newspapers as early as 1883.Even one of the world’s leading dolphin experts, Janet Mann a Georgetown biologist Janet Mann, who co-founded the dolphin project, did not know of their presence there. ‘So much is known about every single species in the Potomac and Chesapeake, except for the charismatic megafauna – bottlenose dolphins. That just astounded me,’ Mann said. The team have witnessed the dolphins giving birth, mating and swimming in the watersBiologist Janet Mann is considered one of the world’s leading dolphin experts and was unaware that bottlenose dolphins were in the Potomac until 2012Mann and Ann-Marie Jacoby (left) co-founded the Potomac-Chesapeake Dolphin Project which is now leading observations on the dolphins’ behavior. The waters were once so polluted that they were described by President Lyndon B. Johnson (right) as a ‘national disgrace’Since their research project began, they have tracked Bottlenose dolphin populations on the rise.Jacoby even witnessed the birth of one on August 17 in salty waters near the Virginian town of Lewisetta.She alongside Georgetown University graduate were tracking 50 dolphins downriver when they noticed a rust-colored trail near to the side of their boat.Jacoby initially feared her team had injured a dolphin but then suddenly thought it may be something else.’I’m like, “Guys, look for a tiny, tiny baby! Look for a tiny baby!”‘ she recalled.Amid a cloudy patch of water there was a dolphin Jacoby didn’t recognize swimming next to an adult female. Jacoby and Mann have spotted the baby in the weeks that have followed. The majority of what is known about the lives of bottlenose dolphins originates from observations in captivity, Mann explained.During their studies they have named more than 600 dolphins after US political leaders and historical leaders including Supreme Court Justices, members of Congress and abolitionists. ‘These are the nation’s dolphins, in a sense,’ Mann added.Recalling the birth of the dolphin earlier this year, Jacoby added: ‘Zachary Taylor was there. George W. Bush was there. Jimmy Carter was there.’Oh, uh, Hillary Clinton was there! I believe Chelsea Clinton was there. I think Alexander Hamilton was there, too.’
Researchers shocked to find 1,000 bottlenose dolphins living in the once polluted Potomac river
