Guianan Red Howler (Alouatta macconnelli), Mahaica River, Guyana. Taken: 21 February, 2016Camera: Canon EOS 7D Mark IIFocal length: 500mmAperture: ƒ/4Shutter speed: 1/800sISO: 500Flash fired: no Guianan Red Howler (Alouatta macconnelli), Mahaica River Taken: 22 September, 2013Camera: Canon EOS 6DFocal length: 420mmAperture: ƒ/7.1Shutter speed: 1/500sISO: 250Flash fired: no Atta Rainforest Lodge, Iwokrama, Guyana Taken: 31 January, 2016Camera: Canon EOS 7D Mark IIFocal length: 700mmAperture: ƒ/5.6Shutter speed: 1/125sISO: 2000Flash fired: yes "What should we do, Ceasar ?" A group of Guianan Red Howlers (Alouatta macconnelli) along the Mahaica River, East Coast Demerara. Taken: 18 May, 2014Camera: Canon EOS 6DFocal length: 700mmAperture: ƒ/8Shutter speed: 1/400sISO: 1250Flash fired: yes Guianan Red Howler (Alouatta macconnelli) sitting at the top of canopy along the Mahaica River. Taken: 22 September, 2013Camera: Canon EOS 6DFocal length: 420mmAperture: ƒ/7.1Shutter speed: 1/400sISO: 250Flash fired: no Guianan Red Howler on Sloth Island, Essequibo River. Taken: 18 January, 2014Camera: Canon EOS 6DFocal length: 420mmAperture: ƒ/6.3Shutter speed: 1/1250sISO: 1000Flash fired: no