Piñon seed assessment by the piñon jay, Gymnorhinus cyanocephalus
Citation
J David Ligon, and Dennis J Martin, Piñon seed assessment by the piñon jay, Gymnorhinus cyanocephalus: .
Summary
Piñon jays (Gymnorhinus cyanocephalus) distinguished accurately between good and bad seeds of piñon pines (Pinus edulis). This was investigated in captives of three age groups: wild-caught adults, hand-reared yearlings, and hand-reared juveniles. All appeared to use visual, tactile (apparently weight) and auditory (‘bill-clicking’) cues. Discrimination improved with practice. Bad seeds weighted with lead shot caused only temporary confusion. Inexperienced piñon jays demonstrated an immediate preference for piñon seeds over other objects. Distinguishing good seeds from bad was learned. ‘Bill-clicking’ apparently is unlearned, as it appears in young birds in a variety of contexts. The relationship between sounds perceived, [...]
Summary
Piñon jays (Gymnorhinus cyanocephalus) distinguished
accurately between good and bad seeds of piñon pines
(Pinus edulis). This was investigated in captives of three age groups:
wild-caught adults, hand-reared yearlings, and hand-reared juveniles.
All appeared to use visual, tactile (apparently weight) and auditory
(‘bill-clicking’) cues.
Discrimination improved with practice. Bad seeds weighted with lead shot
caused only temporary confusion. Inexperienced piñon jays
demonstrated an immediate preference for piñon seeds over
other objects. Distinguishing good seeds from bad was learned.
‘Bill-clicking’ apparently is
unlearned, as it appears in young birds in a variety of contexts. The
relationship between sounds perceived, external coloration, weight, and
seed quality must be integrated by experiential processes. Published in
Animal Behaviour, volume 22, issue 2, on pages 8 - 8, in 1974.