My collaborators at the R.I.D.E. and I will use a manned submarine to tag adult Sixgill sharks (Hexanchus griseus). We will use cutting-edge archival satellite pop-up tags, calibrated with relatively cheap field equipment, available satellite data, and off-the-shelve camera technology, to as accurately as possible find out where these ocean giants migrate. NOBODY KNOWS! We will examine environmental variables associated with movement patterns.