Animals' improvement in capturing cryptic prey with experience has long been attributed to a perceptual mechanism, the specific search image. Detection could also be improved by adjusting rate of search. In a series of studies using both naturalistic and operant search tasks, pigeons searched for wheat, dyed to produce 1 conspicuous and 2 equally cryptic prey types. Contrary to the predictions of the search-rate hypothesis, pigeons given a choice between the 2 cryptic types took the type experienced most recently. However, experience with 1 cryptic type improved accuracy on the other cryptic type, a result inconsistent with a search image specific to 1 prey type. Search image may better be thought of as priming of attention to those features of the prey type that best distinguish the prey from the background.

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Simple SummaryRecent research has called into question the value of the food guarding assessment as a predictive tool for determining the safety of shelter dogs. This study examined the effect of eliminating the food guarding assessment in nine U.S. animal shelters. It was found that when the food guarding assessment was removed, bites or other injuries to staff or adopters did not increase. However, dogs exhibiting food guarding behavior were less likely to be adopted, had a longer shelter stay, and were more likely to be euthanized than dogs in the general population. Based on previous research and this study’s findings, the authors recommend that shelters discontinue the food guarding assessment.AbstractMany shelters euthanize or restrict adoptions for dogs that exhibit food guarding while in the animal shelter. However, previous research showed that only half the dogs exhibiting food guarding during an assessment food guard in the home. So, dogs are often misidentified as future food guarders during shelter assessments. We examined the impact of shelters omitting food guarding assessments. Nine shelters conducted a two-month baseline period of assessing for food guarding followed by a two-month investigative period during which they omitted the food guarding assessment. Dogs that guarded their food during a standardized assessment were less likely to be adopted, had a longer shelter stay, and were more likely to be euthanized. When the shelters stopped assessing for food guarding, there was no significant difference in the rate of returns of food guarding dogs, even though more dogs were adopted because fewer were identified with food guarding behavior. Additionally, the number of injuries to staff, volunteers, and adopters was low (104 incidents from a total of 14,180 dogs) and did not change when the food guarding assessment was omitted. These results support a recommendation that shelters discontinue the food guarding assessment.

Simple SummaryOrganizations responsible for placing dogs seized from dogfighting investigations often must determine if a particular dog should be euthanized because it is too dangerous or if it is safe to place the dog in an adoptive home. In this study, we examine whether the extent of scarring from dog fighting is a reliable predictor of aggression towards other dogs and therefore could be used to help make that decision. We found that dogs with 10 or more scars in the three body zones where dogfighting injuries tend to be concentrated were more likely, on average, to show aggression to other dogs. The relationship is imperfect, however. Many unscarred dogs were dog aggressive while some highly scarred dogs were not. Therefore, we recommend also assessing a dog’s behavior before making decisions about its disposition.AbstractWhen pit bull-type dogs are seized in an investigation of organized dogfighting, heavily scarred dogs are often assumed to be highly dog aggressive due to a history of fighting. These dogs may be deemed dangerous and euthanized based on scarring alone. We analyzed our existing data on dogs seized from four dogfighting investigations, examining the relationship between the dogs’ scars with aggression towards other dogs. Scar and wound data were tallied in three body zones where dogfighting injuries tend to be concentrated. Dog aggression was assessed using a model dog and a friendly stimulus dog in a standardized behavior evaluation. Scarring and dog aggression were significantly related, more strongly among male (Fisher’s Exact p < 0.001) than female dogs (Fisher’s Exact p = 0.05). Ten or more scars in the three body zones was a reasonable threshold with which to classify a dog as high risk for dog aggression: 82% of males and 60% of females with such scarring displayed dog aggression. However, because many unscarred dogs were dog aggressive while some highly scarred dogs were not, we recommend collecting behavioral information to supplement scar counts when making disposition decisions about dogs seized in dogfighting investigations.