The Collaborative International Dictionary of English v.0.48:

fledgeling \fledgeling\, fledgling \fledgling\n.
   a new member of a group.

   Syn: newcomer, fledgeling, starter, neophyte, freshman,
        entrant.
        [WordNet 1.5]

   2. A young bird just fledged. [WordNet sense 2]
      [1913 Webster]

WordNet (r) 3.0 (2006):

fledgeling
    adj 1: (of a young bird) having acquired its flight feathers; "a
           fledgling robin" [syn: fledgling(a), fledgeling(a)]
    n 1: any new participant in some activity [syn: newcomer,
         fledgling, fledgeling, starter, neophyte,
         freshman, newbie, entrant]
    2: young bird that has just fledged or become capable of flying
       [syn: fledgling, fledgeling]