Pecking Preferences Research Articles

Similarity of approach and pecking preferences for spectral stimuli in domestic chicks: absence of a mirror-image relation.

The results of Schaefer and Hess showing that White Rock chicks described mirror-image response functions to spectral stimuli in approach and pecking behavior could not be replicated using Cornish-Cross chicks under more controlled conditions. Our results showed similar blue-orange bimodal functions for both behavioral responses, resembling the approach data of Schaefer and Hess and the earlier pecking data of Hess and others, but not the pecking data reported by Schaefer and Hess.

Prehatch color stimulation effects on color pecking preferences and color discrimination learning in white leghorn chicks.

Four experiments assessed the effects of stimulating chick embryos with colored light at 2 intensity levels. Both posthatch color pecking preferences (Experiments 1 and 2) and color discrimination learning (Experiments 3 and 4) were unaffected. These results affirm and extend a prior finding of no pre- and posthatch colored light stimulation effect on posthatch color preferences in ducklings. The color pecking preferences found replicated prior findings with chicks. However, they differed from the approach color preferences observed in color discrimination learning.

Modification of chicks’ pecking preferences: Food imprinting or instrumental conditioning?

Using Hess’ technique, 35 small groups of chicks of age 2–3 days or beyond were reinforced in training with food for pecking at one visual stimulus (S+) and nonreinforced for pecking at another (S−) and subsequently tested in extinction. In training, pecking was strongly conditioned to S+, but in testing, both number of pecks to and preference for S+ declined as in instrumental conditioning, contrary to Hess’ original report. Results are discussed relative to studies exposing chicks to actual food objects, where an imprinting-like phenomenon has been found.

Form preferences in successive discrimination learning of young chicks.

In four experiments the effects of form and orientation pecking preferences of 1- and 3-day old Vantress X Arbor Acre chicks on successive discrimination learning were determined, using heat reinforcement. Major findings were as follows: (a) The young chick has both circle and verticle orientation pecking preferences that are present during at least the first 3 days after hatching; (b) when either of these preferred cues is the nonreinforced cue, the young chick has difficulty in learning not to respond to it but learns quickly not to respond to an unpreferred cue (e.g., triangle and horizontal oriented dots or bar); and (c) these pecking preferences can be modified by heat reinforcement, and the effects of this conditioning is evidenct in subsequent extinction and retention tests. The main conclusion from these experiments is that form and orientation preferences, like brightness and color preferences, are important developmental constraints on conditioning of the young chick.

Color picking preferences in white leghorn chickens.

Studies of color pecking preferences in newly hatched chicks (Gallus domesticus) have shown unimodal preference in the orange region of the spectrum or bimodal preferences at blue and orange. In the present study, dark-harched White Leghorn chicks were tested in darkness with targets illuminated at 1 or 3 radiant intensity levels. Results showed the least amount of pecking at green (541 nm.) and peak preferences in blue-violet and orange-red regions. Findings were similar when other dark-hatched chicks were tested in the light (Experiment 2). Overall, findings suggest unlearned pecking preferences for short and long wavelengths, with minimums at green. Possible evolutionary and photochemical bases for such a bimodal wavelength preference function were discussed. Since bimodality was unaffected by target intensity and background, these variables probably do not account for the unimodal function reported by others.

Barred Owl Records in Western Montana

lifetime of a bird, as all three accipiters hunt rather elusive prey (primarily birds), and the gradual improvement of hunting techniques seems especially plausible for such prey. Though we have no evidence for or against it, there could be a preferential mating system in which adults with the darkest red eyes could have the greatest success in gaining mates. The disadvantages inherent in red eye coloration might prevent any tendency toward early assumption of this color in inexperienced birds, and the relatively greater danger to eyes of females (the sex that normally feeds chicks) could explain the relatively slow transition to red eyes in this sex. Though one might suggest that age recognition could be achieved without employing the color red, it is questionable whether a preferential mating system based on differences in eye coloration could be SLIStained if the preferred color did not also have disadvantages to its bearer at least at some age in life. Otherwise, selection would presumably lead to a uniform population with preferred eye coloration. The above hypothesis is not without difficulties. It is relevant to note that iris color changes of Marsh Hawks (Circus cyangus), as intensively studied by Hamerstrom ( Inland Bird Banding News 40:43, 1968 ) and Balfour (Bird Study 17:47, 1970), also occur faster in males than in females. In this species the transition from an initial brown coloration to a final yellow coloration takes approximately 1 year for males and up to 6 or 7 years for females. It seems unlikely that the hypothesis developed above could be directly applied to Marsh Hawks, though pecking preferences of Marsh Hawk chicks remain to be explored. A second difficulty concerns the role of an experience factor in delaying red eye coloration in male accipiters. As an order of magnitude guess, the chances of a male losing his mate during the breeding cycle and carrying on alone in feeding chicks might be on the order of one in a hundred breeding attempts.

Stimulus Generalization and Responses To "Supernormal" Stimuli in the Unrewarded Pecking Behavior of Young Chicks

Abstract 1. Young chicks were tested daily from the age of one to nine days for unrewarded pecking preferences. 2. Those tested on stars differing in number of points pecked the most at stars having 3 or 9 points and showed a decreasing preference for intermediate stars with the 7-pointed star pecked at the least. Preference for different stars appears to be influenced by size. 3. There was a failure to obtain classical stimulus generalization effects in the groups shown a series of diamonds or a series of ovals. 4. Preference rankings for "supernormal" stimuli consisting of circles edged in different ways suggested that the preference hierarchy for two-dimensional forms may be very different when the forms are in extremely tiny size.

Innate visual form preferences in the imprinting behavior of hatchling chicks.

Abstract 1. Dark-reared socially naive hatchling chicks 13 to 16 hours old were exposed to one of ten two-dimensional forms in an imprinting procedure. Two different imprinting procedures were used. 2. The relative effectiveness of the ten forms, from high to low, in eliciting affiliative behavior was as follows: square, pentagon, oval, diamond, triangle, serrated circle, star, rectangle, circle, and hexagon. 3. These preferences were compared with the pecking preferences found for the same shapes that have been previously reported by GOODWIN & HESS (190). 4. A comparison of affiliative and pecking behavior was made.

Spectral pecking preference in gull chicks: Possible resolution of a species difference.

Spectral pecking preference in gull chicks: Possible resolution of a species difference.