Carl R. Gustavson

Taste-Aversion Conditioning of Crows to Control Predation on Eggs

Free-ranging crows (Corvus brachyrhynchos) that ate chicken eggs that were painted green and contained a nonlethal toxin subsequently avoided green eggs at various locations, whether or not they contained toxin. The crows also continued to eat unpainted and nontoxic chicken eggs. Illness-induced aversions among predators in nature may be a powerful determiner of the evolution of Batesian mimicry and, in human hands, serve as a practical tool for wildlife ecologists.

Thiabendazole-based taste aversions in dingoes (Canis familiaris dingo) and New Guinea wild dogs (Canis familiaris hallstromi)

Abstract Two experiments were conducted on captive dingoes ( Canis familiaris dingo ) and New Guinea wild dogs ( Canis familiaris hallstromi ) to evaluate: (1) whether these dogs will acquire conditioned food aversions; and (2) to investigate the use of thiabendazole for establishing illness-based food aversions. Of 14 dogs fed thiabendazole-treated lamb, only one continued to consume untreated lamb meat. All 5 dogs which were fed lamb on the same schedules as the treatment animals continued to consume all of the lamb presented. Clearly, thiabendazole produces conditioned taste aversions, and further research for application to canine damage control problems seems justified.

Body-Image Distortion among Male and Female College and High School Students, and Eating-Disordered Patients

For 179 male and female college and high school students, and 26 female eating-disordered patients body-image distortion was measured using a computer-based image-analysis of redrawn images of standardized human figures. Statistical analysis indicated that body-image distortion was the same for all groups. Body-image distortion was significantly and negatively related to weight:heigbt ratio as a function of a simple polynomial. These results suggest this evaluation of distortion of body-image yields a quantitative measure reliably related to weight status but also suggests the technique, and possibly measurement of body-image distortion in general, may not be a valid discriminator between eating-disordered and normal persons.

Anthelmintic-based taste aversions in wolves (Canis lupus)

Abstract The use of lithium chloride (LiCl) as an oral illness-producing agent in taste aversion studies has been questioned. Because of the detectability of LiCl, a different aversion-producing substance may be needed. To test the anthelmintic thiabendazole (TBZ) as an aversion-producing agent, 5 wolves ( Canis lupus ) were tested with 4 different foods. For each test, 2 wolves were given treated food and 3 were used as controls. A different pair of wolves were treated with each food. One wolf did not receive any treated food, while each of the other 4 wolves received treatments with 2 different foods. Treatment consisted of mixing 500 g of food with 2 g of TBZ. Of the 4 times wolves were treated, one, using chicken franks, produced no apparent aversions. Reductions in consumptions for the remaining 3 foods were 29% with spaghettios, 75% with dog food, and 100% with turkey soup.

BODY-IMAGE DISTORTION AMONG MALE AND FEMALE AMERICAN AND COSTA RICAN STUDENTS AND FEMALE JAPANESE STUDENTS

395 American male and female high school and college students, 286 Costa Rican male and female high school students, and 127 Japanese female college students were tested for body-image distortion using a computer-based body-image distortion task. A reliable negative relationship between stature and body-image distortion was observed. No reliable differences in body-image distortion were observed between different sex or cultural groups.

An evaluation of taste aversion control of wolf (Canis lupus) predation in Northern Minnesota

Abstract Lithium chloride-laced cow-baits were placed on a ranch in prime wolf habitat in Northern Minnesota. Decreased bait consumption over the summer, and an experimental control for the effects of season, suggested that bait aversions were established in the wolf ( Canis lupus ) population. Since losses were historically low on the ranch, loss reduction may not have been an appropriate indicator of predation prevention. The dramatically decreased number of wolves taken from the ranch, compared to previous years, without a concurrent increase in depredation, suggests limited success.

CLINICAL CORRELATES OF BODY-SIZE DISTORTION "'

Body-size distortion has been considered a central symptom of eating disorders. We studied 35 female eating-disordered patients and 85 controls using a computer-based body-size estimation technique. We have found almost identical linear relationships between body-size distortion and weight:height ratios in both groups. In the clinical group, distortion scores were not correlated with scores on the Eating Attitudes Test or Beck Depression Inventory but were negatively correlated with body dissatisfaction as measured on the Eating Disorder Inventory. These results raise further questions about the role of body-size distortion both as a diagnostic criterion and as a complicating phenomenon in eating disorders.

Food avoidance in rats: The differential effects of shock, illness and repellents

Rats were exposed to a variety of noxious stimuli that may be used in wildlife management, i.e., repellents, conditioned repellents and poison. Changes in the latency to food approach and the amount of food consumed were consistent with previous research which suggests that important differences exist between toxin-induced illness and aversive stimulation of skin, nose or mouth.

An evaluation of phenol methylcarbamates as taste aversion producing agents in caged blackbirds

Abstract Mesurol, 3,5-dimethyl-4-(methylthio) phenol methylcarbamate, is registered as a repellent for bird damage control on cherries and grapes, and several field evaluations have suggested decreased damage with Mesurol application. This laboratory experiment with a colony of mixed blackbird species suggests that Mesurol-dusted sunflower meats consumed by blackbirds alters the subsequent palability of untreated seeds rather than the presence of the Mesurol serving directly to repel birds from the crop. In a second experiment, methylcarbamate-impregnated seeds and non-treated seeds were evenly spread in different sunflower plots containing blackbirds. Reduced rates of sunflower damage in treated areas compared to the control areas suggest this technique may be promising.

Body-image dissatisfaction among American male and female college students : a computer-based graphical approach

College students (56 women and 43 men) attending state colleges in the southwestern United States were tested for body-image dissatisfaction using a computer-based graphical body-image task. A reliable relationship between desired stature and desired body-image was observed for the women. Women of large stature showed a greater discrepancy between verbally reported desired stature and redrawn images of desired stature than women of average or smaller than average stature. No reliable discrepancy between desired body-image and verbally reported desired stature was shown by the men.