If you feel you are starving then up them a bit- I recommend what Heather says, start at 2000 then work you way down.
Since you are 280 your body needs more calories to function overall- dip too low and your metabolism slows down? So eating 1600 a day may work for a while, but if you are constantly hungry and tired your body will slow down your metabolism to compensate and you'll stop losing. When I was doing 1200 a day I wasn't losing, then I upped it to 1350-1500 a day and started losing again- go figure! Course now I am carb counting so that's different.
Good luck- a lot of it is trial and error too.