The Collaborative International Dictionary of English v.0.48:

Depredation \Dep`re*da"tion\, n. [L. depraedatio: cf. F.
   d['e]pr['e]dation.]
   The act of depredating, or the state of being depredated; the
   act of despoiling or making inroads; as, the sea often makes
   depredation on the land.
   [1913 Webster]

WordNet (r) 3.0 (2006):

depredation
    n 1: an act of plundering and pillaging and marauding [syn:
         depredation, predation]
    2: (usually plural) a destructive action; "the ravages of time";
       "the depredations of age and disease" [syn: ravage,
       depredation]

Moby Thesaurus II by Grady Ward, 1.0:

63 Moby Thesaurus words for "depredation":
   banditry, bloodbath, blue ruin, breakup, brigandage, brigandism,
   carnage, consumption, damnation, decimation, desolation,
   despoiling, despoilment, despoliation, destruction, devastation,
   direption, disintegration, disorganization, disruption,
   dissolution, foraging, foray, freebooting, havoc, hecatomb,
   holocaust, laying waste, looting, marauding, perdition, pillage,
   pillaging, plunder, plundering, raid, raiding, ransacking, rape,
   rapine, ravage, ravagement, ravages, ravaging, ravishment, razzia,
   reiving, rifling, robbery, ruin, ruination, sack, sacking,
   shambles, slaughter, spoiling, spoliation, undoing, vandalism,
   waste, wrack, wrack and ruin, wreck



Bouvier's Law Dictionary, Revised 6th Ed (1856):

DEPREDATION, French law. The pillage which is made of the goods of a
decedent. Ferr. Mod. h.t.