Slender-billed Prion Slender-billed Prion Pachyptila belcheri Mar 1 2019. Southern Ocean, 65S 164E. Mar 1 2019. Southern Ocean, 65S 164E. Mar 1 2019. Southern Ocean, 65S 164E. Mar 1 2019. Southern Ocean, 65S 164E. Mar 1 2019. Southern Ocean, 65S 164E. Mar 1 2019. Southern Ocean, 65S 164E. Mar 1 2019. Southern Ocean, 65S 164E. Mar 1 2019. Southern Ocean, 65S 164E.