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The diverse ecology of parasitoids is shaped by extrinsic competition, i.e., exploitative or interference competition among adult females and males for hosts and mates. Adult females use an array of morphological, chemical, and behavioral mechanisms to engage in competition that may be either intra- or interspecific. Weaker competitors are often excluded or, if they persist, use alternate host habitats, host developmental stages, or host species. Competition among adult males for mates is almost exclusively intraspecific and involves visual displays, chemical signals, and even physical combat. Extrinsic competition influences community structure through its role in competitive displacement and apparent competition. Finally, anthropogenic changes such as habitat loss and fragmentation, invasive species, pollutants, and climate change result in phenological mismatches and range expansions within host–parasitoid communities with consequent changes to the strength of competitive interactions. Such changes have important ramifications not only for the success of managed agroecosystems, but also for natural ecosystem functioning. [ABSTRACT FROM AUTHOR]

Highlights • Resource guarding aggression may be reduced by teaching dogs to drop items. • High impulsivity and fear increased likelihood of resource guarding aggression. • Resource guarding behaviour patterns were relatively fixed in the presence of dogs. Abstract Resource guarding (RG) involves the use of specific behaviour patterns to control access to an item of potential "value" (as perceived by the dog), and can be expressed in the presence of various animals, including other dogs. The current study aimed to identify factors associated with RG patterns expressed around other dogs. Dog owners (n = 3068) were recruited through social media to answer questions regarding dog- and household-related factors, as well as their dog's current and past behaviour around resources in the presence of other dogs. Participants were screened for their ability to identify different forms of resource guarding from video, and were removed from the study if they incorrectly identified any of the videos provided. This resulted in a final sample of 2207 participants (n = 3589 dogs). Multiple multi-level logistic regression models were developed to determine the association between independent variables of interest and RG patterns (i.e., RG aggression, avoidance, and rapid ingestion) when in the presence of other dogs. Namely, dogs living in multi-dog households were more likely to display RG aggression, avoidance, and rapid ingestion (p < 0.01) compared to dogs that live without other dogs. Dogs with higher levels of impulsivity and fear were more likely to display RG aggression (p < 0.001). Neutered males (p < 0.01) were more likely to be RG aggressive compared to dogs of other sexes and neuter statuses. Teaching dogs to reliably "drop" items when requested was associated with a reduced likelihood of biting RG aggression (p < 0.05). Distinct associative relationships between the patterns of RG in the presence of other dogs were identified. Dogs that express RG aggression were less likely to express RG avoidance or RG rapid ingestion; however, the latter two types were likely to co-occur, perhaps dependent on the type of resource involved. This suggests that dogs may be relatively more fixed in their action around items in the presence of dogs. However, a longitudinal study is important to determine the exact nature of relationships between RG patterns. The results identified in this study can be used as a basis for further investigation on factors influencing RG behaviour in the presence of other dogs. [ABSTRACT FROM AUTHOR]

Highlights • Resource guarding aggression may be reduced by teaching dogs to drop items. • Adding palatable food during meals may reduce resource guarding behaviour. • Removing the food dish during meals may increase resource guarding behaviour. • Resource guarding behaviour patterns are flexible in the presence of people. Abstract Resource guarding (RG) involves the use of specific behaviour patterns to control access to an item of potential "value" to the dog. Of particular concern are patterns involving aggression, due to safety concerns, but other patterns of RG behaviour are prevalent and include avoidance (i.e., positioning of the head or body to maintain item control, or location change with the item) and rapid ingestion (i.e., rapid ingestion of a consumable item). Current research has not investigated the etiology of RG aggression in depth, nor have the additional patterns of resource guarding been considered. Dog owners (n = 3068) were recruited through social media to answer questions regarding dog- and household-related factors, as well as their dog's current and past behaviour around resources in the presence of people. Participants were screened for their ability to identify different forms of resource guarding from video, and were removed from the study if they incorrectly identified any of the videos provided. This resulted in a final sample of 2207 participants representing information for 3589 dogs. Multiple multi-level logistic regression models were developed to determine the association between independent variables of interest and each pattern of resource guarding. Dogs with higher levels of impulsivity were more likely to display avoidance, rapid ingestion and aggressive RG (p < 0.001), and dogs with higher levels of fearfulness were also more likely to display RG aggression (p < 0.001). Neutered males (p < 0.01) and mixed breeds (p < 0.05) were more likely to be RG aggressive compared to dogs of other sexes, neuter statuses, and breeds. Teaching dogs to reliably "drop" items when requested was associated with a reduced likelihood of RG aggression (p < 0.01) and avoidance (p < 0.001). Furthermore, the addition of palatable bits of food during mealtime was associated with an increased likelihood of less severe RG behaviour (p < 0.01), whereas removal of the food dish during mealtime was associated with an increased likelihood of expressing more severe or frequent RG behaviours (p < 0.05). Relationships between the three types of RG patterns were varied, suggesting that RG behaviour patterns are flexible when humans are involved. The results highlight various factors that might predispose dogs to RG behaviour and potential methods for prevention of RG aggression, and can serve as a basis for future longitudinal RG research to establish causation. [ABSTRACT FROM AUTHOR]

Some shelters in the United States consider dogs identified as food aggressive during behavioral evaluations to be unadoptable. We surveyed adopters of dogs from a New York shelter to examine predictive abilities of shelter behavioral evaluations and owner surrender profiles. Twenty of 139 dogs (14.4%) were assessed as resource guarding in the shelter. We found statistically significant associations between shelter assessment as resource guarding and guarding reported in the adoptive home for three situations: taking away toys, bones or other valued objects; taking away food; and retrieving items or food taken by the dog. Similarly, owner descriptions of resource guarding on surrender profiles significantly predicted guarding in adoptive homes. However, positive predictive values for all analyses were low, and more than half of dogs assessed as resource guarding either in the shelter or by surrendering owners did not show guarding post adoption. All three sources of information regarding resource guarding status (surrender profile, shelter behavioral evaluation, and adopter report) were available for 44 dogs; measures of agreement were in the fair range. Thus, reports of resource guarding by surrendering owners and detection of guarding during shelter behavioral evaluations should be interpreted with caution because neither source of information consistently signaled guarding would occur in adoptive homes.

The terms possessive aggression and resource guarding are often used interchangeably to describe behavior patterns used by a dog to control primary access to a perceived valuable item. The use of inconsistent terminology may impact the effectiveness of communication between dog owners and clinicians, affect treatment and management success for the behavior, and inhibit research progress. The aim of this study was to explore the opinions of canine behavior experts on the meaning of and preference for the terms possessive aggression and resource guarding, as well as to develop and propose an operational ethological definition for the preferential term identified. Eighty-five individuals met the inclusion criteria and were invited to participate in a two-stage online survey. Results from the two-stage survey found that the majority of participants preferred the term resource guarding. Detailed exploration of meaning and definitions required in-depth discussion beyond traditional survey methods, therefore, respondents from the second stage of the survey were invited to participate in an online discussion board. Following content analysis of the data from the discussion board, we conclude that the majority of participants preferred the term resource guarding. Considering 100% consensus was not reached regarding terminology among experts in the field, future authors and clinicians should provide clear definitions where terms are applied to ensure effective communication between all parties and to ensure consistency in canine behavior research. Based on expert contributions, we define resource guarding as “the use of avoidance, threatening, or aggressive behaviors by a dog to retain control of food or non-food items in the presence of a person or other animal.”

Some domestic dogs aggressively guard resources. Canine resource guarding impacts public health through dog bites and affects dog welfare through adoption and euthanasia policies at animal shelters. However, little is known about the demographic characteristics and adoption success of dogs assessed as resource guarders during shelter behavioral evaluations. I reviewed nearly five years of records from a New York (NY) SPCA and categorized 1016 dogs by sex; age; size; reproductive status; and resource guarding. I then examined how these characteristics influenced the returns of dogs by adopters. The prevalence of resource guarding in this shelter dog population was 15%. Resource guarding was more common in adult and senior dogs than in juvenile dogs; and it was more common in small and large dogs than medium-sized dogs. Spayed females were more likely than intact females to guard food; neutered males and intact males did not differ in their likelihood of food guarding. Most dogs identified as resource guarders showed mild to moderate guarding. Severe guarders were more likely to be returned by adopters; although almost all were eventually re-adopted and not returned to the shelter. Data presented here provide the most comprehensive description of resource guarders in a shelter dog population and show the successful re-homing of most.

Two household dogs, a 2 year, 8-month-old, spayed female, mixed-breed dog, and a 4 year, 1-month-old, spayed female, mixed-breed dog, presented with a history of aggression toward each other, when in possession of food or other high-value items, and when one approached the other while resting. They responded satisfactorily to treatment with serotonergic drugs, avoidance of provocative situations, and environmental and behavioral modification. [ABSTRACT FROM AUTHOR]

Nicrophorine beetles use small vertebrate carrion for breeding resource. While Nicrophorus spp. have highly developed biparental care, no form of parental care is recorded for Ptomascopus spp. We examined two effects of resource guarding by Ptomascopus morio. The presence of parents, especially the female, reduced the number of fly larvae on chicken carrion. Parents also enhanced the survival of brood faced with predation by the rove beetle, Ontholestes gracilis. In 6 out of 20 trials, the rove beetle predators were killed by Ptomascopus morio parents. We conclude that Ptomascopus morio has a simple, and possibly primitive form of parental care.

1. Oviposition site preference and its relation to offspring performance have received much attention in studies of herbivorous insects. Although this relationship is of great ecological significance, its presence in predacious and omnivorous insects has hardly been explored. When selecting an oviposition site, omnivores are expected to respond to both prey availability and, even more strongly, to plant traits that affect both females and their offspring. 2. In this study, females of Orius albidipennis (Heteroptera: Anthocoridae) showed a strong preference for oviposition at the vein origin site of cotton leaves. It appears that this site is a limited resource for ovipositing females, because they defend it against conspecific intruders. This defensive behaviour was significantly more pronounced on nitrogen-rich than nitrogen-poor plants. 3. The females' defensive behaviour on nitrogen-rich leaves corresponds with offspring performance; the nymphs developed faster and enjoyed higher survival on nitrogen-rich than on nitrogen-poor leaves. At the between-plant level, oviposition preference was not significantly correlated with offspring performance, and egg hatching rate did not differ significantly between nitrogen treatments. 4. Oviposition site selection by this omnivorous bug appears, however, to be correlated positively with offspring performance at the within-leaf level. This is supported by the significantly higher hatching success of eggs deposited at the preferred vein origin site as compared with those deposited on other parts of the leaf. [ABSTRACT FROM AUTHOR]

Simple Summary: Some domestic dogs guard resources and display behaviors such as growling, snarling, or biting when approached. Most animal shelters test for food-related aggression and some consider dogs assessed as food aggressive to be unadoptable and candidates for euthanasia. We surveyed adopters of 139 dogs assessed as either resource guarding (n = 20) or non-resource guarding (n = 119) at a New York (NY) shelter to determine whether shelter identification as food aggressive was associated with guarding in adoptive homes. We also examined whether description of resource guarding in owner reports completed when surrendering a dog to the shelter predicted guarding in adoptive homes. Statistically, shelter assessment as resource guarding and owner-supplied information indicating resource guarding were each associated with guarding in adoptive homes. However, more than half of dogs either assessed by shelter staff or described by surrendering owners as resource guarding did not guard in adoptive homes. Our data indicate that information from surrendering owners, while potentially helpful, is not always predictive of a dog's behavior in an adoptive home, and most importantly, that shelters should not consider all dogs assessed as resource guarding to be unadoptable because many of these dogs do not display guarding behavior post adoption. Some shelters in the United States consider dogs identified as food aggressive during behavioral evaluations to be unadoptable. We surveyed adopters of dogs from a New York shelter to examine predictive abilities of shelter behavioral evaluations and owner surrender profiles. Twenty of 139 dogs (14.4%) were assessed as resource guarding in the shelter. We found statistically significant associations between shelter assessment as resource guarding and guarding reported in the adoptive home for three situations: taking away toys, bones or other valued objects; taking away food; and retrieving items or food taken by the dog. Similarly, owner descriptions of resource guarding on surrender profiles significantly predicted guarding in adoptive homes. However, positive predictive values for all analyses were low, and more than half of dogs assessed as resource guarding either in the shelter or by surrendering owners did not show guarding post adoption. All three sources of information regarding resource guarding status (surrender profile, shelter behavioral evaluation, and adopter report) were available for 44 dogs; measures of agreement were in the fair range. Thus, reports of resource guarding by surrendering owners and detection of guarding during shelter behavioral evaluations should be interpreted with caution because neither source of information consistently signaled guarding would occur in adoptive homes. [ABSTRACT FROM AUTHOR]

Simple Summary: Canine aggression over resources such as food or edible chews is commonly termed food guarding or food aggression. Food aggression directed at humans is relatively common in dogs, including dogs that enter animal shelters. While food aggression is part of dogs' normal behavior, little is known about why some dogs show food aggression, but others do not. Common animal shelter "lore" suggests that dogs that are underweight or were previously starved are more likely than normal-weight dogs to show aggression toward a human that approaches while the dog is eating. It is assumed that the value of food to the dog is increased by experience with food scarcity, and the value remains elevated even after food is no longer scarce. We tested this common belief by analyzing data from 900 dogs from criminal cruelty cases to look for a relationship between the dogs' weight and human-directed food aggression. Contrary to common belief, we found that underweight dogs were not more likely than normal-weight dogs to be food aggressive. Based on these results, human-directed food aggression is not a reliable indicator of past food scarcity. This has implications for criminal proceedings, as dogs can have previously experienced starvation without obvious residual behavioral indications in the shelter. It is commonly believed that underweight or emaciated dogs are predisposed to food aggression toward humans. Each year, the American Society for the Prevention of Cruelty to Animals (ASPCA) receives hundreds of dogs from criminal cruelty cases. The dogs range from emaciated to overweight. We analyzed existing data from 900 such dogs to examine the relationship between body condition score and food and chew item aggression toward humans. Across all types of cruelty cases, 9.2% of dogs were aggressive over the food, chew, or both, which is a lower prevalence than that previously reported among shelter dogs. Dogs from cruelty cases originating in New York City were more likely to show aggression over food (z = 3.91, p < 0.001) and chew items (z = 2.61, p = 0.01) than dogs from large-scale cruelty cases, although it is unclear why. Female dogs were less likely to show food (z = −3.75, p < 0.001) and chew item (z = −2.25, p = 0.02) aggression compared to males. Underweight dogs were not more likely to display food aggression, but when they did, the aggression was no more severe than that of normal-weight dogs (Fisher's exact tests = 0.41 and 0.15 for the Food Bowl and Chew Item scenarios, respectively). Breed type was not a significant predictor of aggression. Canine food aggression does not appear to be an aberrant behavior caused by a history of food scarcity but may be related to biological factors such as sex. These findings could prove useful for animal behavior subject matter experts testifying in court or consulting on cruelty cases, as they could speak with scientific validity to the question of whether there is a link between previous food scarcity and the likelihood of food aggression in dogs. [ABSTRACT FROM AUTHOR]

Birds of prey are highly complex and intelligent species with many of their activities deeply rooted in modal action patterns, such as foraging, courtship and nest building, migration, bathing, or preening. Raptors in managed care are susceptible to presenting undesired behavior when the environment provides antecedents for these behaviors and consequences to maintain them. This article aims to describe concepts of behavior in birds of prey in managed care, with inferences from their wild counterparts, to assist in understanding the etiologies and management of undesired behaviors., Competing Interests: Disclosure The authors have nothing to disclose., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Simple Summary: Dogs that aggressively guard resources, such as food, toys, and sleeping sites, can pose risk to people unfamiliar with canine communication. Such dogs also present challenges to animal shelters, which typically screen for food-related guarding during behavioral evaluations. Some shelters euthanize dogs that aggressively guard food, whereas others restrict adoptions. However, few studies have examined the characteristics and adoption success of dogs that guard food in shelters. I analyzed demographic data and adoption success of dogs assessed as resource guarders at a shelter in New York (NY) over a nearly five-year period. Fifteen percent of the dog population was identified as resource guarders during shelter behavioral evaluations. Resource guarding was more common in adults and seniors than in juveniles, and it was more common in small and large dogs than medium-sized dogs. While spayed females were more likely than intact females to guard food, neutered males and intact males did not differ in their propensity to guard food. Dogs that showed severe guarding were more likely to be returned by adopters, but almost all were successfully re-adopted. These findings provide a detailed description of food guarders in a shelter dog population and show that most such dogs were successfully re-homed. Some domestic dogs aggressively guard resources. Canine resource guarding impacts public health through dog bites and affects dog welfare through adoption and euthanasia policies at animal shelters. However, little is known about the demographic characteristics and adoption success of dogs assessed as resource guarders during shelter behavioral evaluations. I reviewed nearly five years of records from a New York (NY) SPCA and categorized 1016 dogs by sex; age; size; reproductive status; and resource guarding. I then examined how these characteristics influenced the returns of dogs by adopters. The prevalence of resource guarding in this shelter dog population was 15%. Resource guarding was more common in adult and senior dogs than in juvenile dogs; and it was more common in small and large dogs than medium-sized dogs. Spayed females were more likely than intact females to guard food; neutered males and intact males did not differ in their likelihood of food guarding. Most dogs identified as resource guarders showed mild to moderate guarding. Severe guarders were more likely to be returned by adopters; although almost all were eventually re-adopted and not returned to the shelter. Data presented here provide the most comprehensive description of resource guarders in a shelter dog population and show the successful re-homing of most. [ABSTRACT FROM AUTHOR]

The terms possessive aggression and resource guarding are often used interchangeably to describe behavior patterns used by a dog to control primary access to a perceived valuable item. The use of inconsistent terminology may impact the effectiveness of communication between dog owners and clinicians, affect treatment and management success for the behavior, and inhibit research progress. The aim of this study was to explore the opinions of canine behavior experts on the meaning of and preference for the terms possessive aggression and resource guarding , as well as to develop and propose an operational ethological definition for the preferential term identified. Eighty-five individuals met the inclusion criteria and were invited to participate in a two-stage online survey. Results from the two-stage survey found that the majority of participants preferred the term resource guarding . Detailed exploration of meaning and definitions required in-depth discussion beyond traditional survey methods, therefore, respondents from the second stage of the survey were invited to participate in an online discussion board. Following content analysis of the data from the discussion board, we conclude that the majority of participants preferred the term resource guarding . Considering 100% consensus was not reached regarding terminology among experts in the field, future authors and clinicians should provide clear definitions where terms are applied to ensure effective communication between all parties and to ensure consistency in canine behavior research. Based on expert contributions, we define resource guarding as "the use of avoidance, threatening, or aggressive behaviors by a dog to retain control of food or non-food items in the presence of a person or other animal."