These are the last desperate moments of a mother dolphin and her calf.
The video obtained by Reuters shows the baby dolphin rolled over on its side, floating along the oily surface as its mother nudges her head above to stay alive.
Their fight comes a month after a ship ran aground and spilled oil off the coast of Mauritius.
At least 40 dolphins have been found dead in Mauritian waters, including the mother and baby.
They've washed ashore since Monday, when the Japanese ship that leaked oil was was scuttled.
It's feared that the death toll may rise further.
Yasfeer Heenaye, the fisherman who filmed the mother and baby, said he saw nearly 200 dolphins inside the reef Friday morning, and between 25 to 30 of them were dead.
On Saturday, thousands of protesters demonstrated in the capital Port Louis to demand an investigation into the spill.
The government has said it will carry out autopsies on all the dead dolphins and has set up a commission to look into the oil spill.
A government-run research center has conducted autopsies on two of the dolphins so far. Preliminary results found signs of injury but no hydrocarbons.