Veterinarian William Guerra Neto (R) and an assistant take measurements of two Amazonian manatees who are being rehabilitated after sustaining injuries from hunting and fishing nets at the Center of Amazonian Manatees at Amana Lake in Maraa, Amazonas state, Brazil, September 21, 2015. The Amazonian manatee is relatively easy to hunt, and is threatened as a result. It is also at risk from pollution, accidental drowning in commercial fishing nets, and the degradation of vegetation by soil erosion resulting from deforestation, according to the Center of Amazonian Manatees. (Photo by Bruno Kelly/Reuters)





Veterinarian William Guerra Neto (2nd R) and an assistant take measurements of two Amazonian manatees who are being rehabilitated after sustaining injuries from hunting and fishing nets at the Center of Amazonian Manatees at Amana Lake in Maraa, Amazonas state, Brazil, September 21, 2015. (Photo by Bruno Kelly/Reuters)





Veterinarian William Guerra Neto (R) and his assistants take measurements of one of two Amazonian manatees who are being rehabilitated after sustaining injuries from hunting and fishing nets at the Center of Amazonian Manatees at Amana Lake in Maraa, Amazonas state, Brazil, September 21, 2015. (Photo by Bruno Kelly/Reuters)





Veterinarian William Guerra Neto (2nd L) and his assistants take measurements of one of two Amazonian manatees who are being rehabilitated after sustaining injuries from hunting and fishing nets at the Center of Amazonian Manatees at Amana Lake in Maraa, Amazonas state, Brazil, September 21, 2015. (Photo by Bruno Kelly/Reuters)





Veterinarian William Guerra Neto (2nd L) and his assistants take measurements of one of two Amazonian manatees who are being rehabilitated after sustaining injuries from hunting and fishing nets at the Center of Amazonian Manatees at Amana Lake in Maraa, Amazonas state, Brazil, September 21, 2015. (Photo by Bruno Kelly/Reuters)





Veterinarian William Guerra Neto uses telemetry systems to monitor the movement of Amazonian manatees who are being rehabilitated after sustaining injuries from hunting and fishing nets near the Center of Amazonian Manatees at Amana Lake in Maraa, Amazonas state, Brazil, September 19, 2015. (Photo by Bruno Kelly/Reuters)





An Amazonian manatee which is in rehabilitation after sustaining injuries from hunting and fishing nets peers out of the water at the Center of Amazonian Manatees at Amana Lake in Maraa, Amazonas state, Brazil, September 19, 2015. (Photo by Bruno Kelly/Reuters)