Agapornis Roseicollis Research Articles

The effect of recorded contact calls on the reinforcing value of self-viewing among lovebirds

Peachfaced lovebirds ( Agapornis roseicollis ) were conditioned to emit an instrumental response in order to see their own image in a mirror or their own image associated with recorded contact calls. This latter association of stimuli was a more efficient reinforcer.

Auditory and visual stimuli as reinforcers among lovebirds ( Agapornis roseicollis)

Two groups of Agapornis roseicollis were submitted to an operant conditioning paradigm. The operant response was perching which resulted in either visual stimulus or auditory stimulus or both simultaneously. The visual stimulus consisted of the image of the subject in a one-way mirror, the auditory stimulus of a vocal contact with another lovebird. The presentation of visual stimulus led to a significant increase in the mean perching time on the reinforced perch. This stimulus was thus a highly positive reinforcer, and its positive value was increased even more by the simultaneous presentation of the auditory stimulus. By contrast, partner's vocalizations, given as a reinforcer, induced no increase in perching time on the reinforced perch. Another group was submitted to two experiments to test the reinforcing value of contact calls only. In one experiment, the operant response triggered the repetitive emission of recorded contact calls; in the other, it stopped the continuous and repetitive emission of the calls. Results showed that in this situation birds suppressed the sound of contact calls. These results are discussed in terms of the relationship between visual and auditory stimuli in social communication among these birds.

Microsporidian Infection in the Pied Peach-Faced Lovebird (Agapornis roseicollis)

A microsporidian infection was diagnosed in a pied peach-faced lovebird (Agapornis roseicollis) which had died after an illness of 2 days. The parasite was observed in the liver, kidney, and small intestine. Lesions were most severe in the liver, with numerous organisms adjacent to areas of hepatic necrosis. Although the organisms were seen within renal tubules and within the intestinal mucosa, inflammatory lesions in those sites were minimal. The microsporidian nature of the parasite was confirmed by morphologic studies. The genus of the organism was not determined.

Hearing and communication in birds: the cocktail-party-effect in intraspecific communication of Agapornis roseicollis (aves, psittacidae).

Abstract Lovebirds ( Agapornis roseicollis ) were able to detect recorded acoustic signals of their mates from background noise (vocalizations of birds of the same species); signal-to-noise ratio 13 dB. Signal detection and intelligibility at different levels is so far known to be based on two components: The preferential motivation of the signal recipient as a psycho-physical factor, and - in the case of voice recognition in background noise - the possession of two ears as the physical factor. Since this complex phenomenon, termed the cocktail-party-effect, has first been investigated in the acoustic behaviour of humans (1,2), ethologists have supposed that this effect also exists in the animal acoustic behaviour of Vertebrates (3,4,5) and probably Invertebrates (pers. comm.).

Structure and colour-production of the blue barbs of Agapornis roseicollis and Cotinga maynana.

The spongy structure in medullary cells responsible for the colour of blue barbs in rump feathers of Agapornis roseicollis and back feathers of Cotinga maynana is studied with the scanning and the transmission electron microscope. The Agapornis structure is an irregular three-dimensional network of connected keratin rods which in many places form rings with outer diameters 0.25–0.3 μ. The air-filled space likewise consists of an irregular network of connected channels. The Cotinga structure consists of spherical cavities fairly evenly distributed in a keratin matrix.

Approach-withdrawal behavior of peach-faced lovebirds, Agapornis roseicolis, and its modification by brain lesions.

I. The frequency of mobbing vocalizations (chips, squeaks, chitters) and wing-beating was increased by the presence of a strange object (a small wooden cylinder) in the cage. The relative increase produced by the cylinder was much greater in birds that were partially isolated from the sounds as well as the sight of others than in birds only visually isolated. 2. The number of mobbing displays given by 20-hour food-deprived birds in response to the cylinders was sharply reduced by simultaneous presentation of food (even though the birds did not eat) but remained significantly above that given to food alone. This effect was observed in all lesioned birds as well as in intact controls. 3. A peculiar vocalization is described and termed singing because of some resemblance to subsong of passerines. It included all the vocalizations encountered in mobbing but occurred mostly in birds that appeared drowsy and was inhibited by stimuli that produced mobbing. 4. Brain lesions that destroyed the medial archistriatum bilaterally greatly reduced the frequency of mobbing displays in response to unfamiliar objects, and simultaneously decreased withdrawal and avoidance and increased some approach behavior. 5. Lesions of the hyperstriatum increased mobbing displays and probably increased the inhibitory effect of the cylinders on feeding compared to intact birds.

Oestrogen stimulation of nest material preparation in the peach-faced lovebird ( Agapornis roseicollis)

The purpose of this study was to determine whether the behaviour involved in nest material preparation by female Agapornis roseicollis is stimulated at least in part by an oestrogen and at what age this behaviour can first be induced with an exogenous hormone. A pilot study indicated that an oestrogen (diethylstilbestrol) can stimulate nest material preparation, but only after the female has reached a certain minimum age. A second experiment, using a single cross-over design, was made to determine this age. Four 10-week-old females received oestrogen pellet implants; four others were given control pellets. After 9 weeks the treatments were reversed, the control birds now receiving oestrogen. Measures of the treatment effects were the number of strips cut from paper sheets and the area of paper left uncut. The treated birds showed nest material preparation beginning in the 3rd week of treatment, peaking at weeks 6 and 7 and decreasing in weeks 8 and 9. The control birds showed almost no nest material preparation until after treatment reversal. These responses indicate that preparation of nest material in A. roseicollis is mediated at least in part by oestrogen and that immature females can be stimulated to this activity at least 2 weeks before they would normally begin.