The Collaborative International Dictionary of English v.0.48:

Percher \Perch"er\, n. [From Perch, v. i.]
   1. One who, or that which, perches. --J. Burroughs.
      [1913 Webster]

   2. One of the Insessores.
      [1913 Webster]

   3. [From Perch a pole.] A Paris candle anciently used in
      England; also, a large wax candle formerly set upon the
      altar. [Obs.] --Bailey.
      [1913 Webster]

WordNet (r) 3.0 (2006):

percher
    n 1: a person situated on a perch
    2: a bird with feet adapted for perching (as on tree branches);
       this order is now generally abandoned by taxonomists [syn:
       Insessores, order Insessores, perching bird, percher]