A simplified protocol for detecting two systemic bait markers (Rhodamine B and iophenoxic acid) in small mammals

We developed a method of quantifying levels of fluorescence in the whiskers of wild stoats (Mustela erminea) using fluorescence microscopy and Axiovision 3.0.6.1 software. The method allows for discrimination between natural fluorescence present in or on a whisker, and the fluorescence resulting from the ingestion of the systemic marker Rhodamine B (RB), although some visual judgement is still required. We also developed a new high performance liquid chromatography (HPLC) protocol for detecting the systemic marker iophenoxic acid (IPA) in the blood of laboratory rats (Rattus norvegicus) and wild stoats. With this method, the blood of an animal that has consumed IPA can be tested for the presence of the foreign IPA compound itself. This is a more reliable test than the previous method, which measured the raised level of natural blood protein-bound iodine correlated with IPA absorption. The quantity of blood required from animal subjects is very small (10 μl), so the testing is less intrusive and the method can be extended to smaller species. The extraction technique uses methanol, rather than acids and heavy metal salts, thereby simplifying the procedure. Recovery of IPA is quantitative, giving a highly reliable reading. In experiments on captive rats the IPA method proved successful. Of 12 positively marked carcasses, two that had not been frozen for the 24 h before blood samples were taken showed relatively lower IPA levels. The same IPA detection method, as well as the whisker analysis for RB, was applied successfully to a population of wild stoats to which both Rhodamine B and IPA were made available at bait stations. The presence of both bait markers was detectable in rats for at least 21 days and in stoats for at least 27 days

A moral panic over cats

Some conservationists believe that free-ranging cats pose an enormous risk to biodiversity and public health and therefore should be eliminated from the landscape by any means necessary. They further claim that those who question the science or ethics behind their arguments are science deniers (merchants of doubt) seeking to mislead the public. As much as we share a commitment to conservation of biodiversity and wild nature, we believe these ideas are wrong and fuel an unwarranted moral panic over cats. Those who question the ecological or epidemiological status of cats are not science deniers, and it is a false analogy to compare them with corporate and right-wing special interests that perpetrate disinformation campaigns over issues, such as smoking and climate change. There are good conservation and public-health reasons and evidence to be skeptical that free-ranging cats constitute a disaster for biodiversity and human health in all circumstances. Further, there are significant and largely unaddressed ethical and policy issues (e.g., the ethics and efficacy of lethal management) relative to how people ought to value and coexist with cats and native wildlife. Society is better served by a collaborative approach to produce better scientific and ethical knowledge about free-ranging cats

Acceptance of Simulated Oral Rabies Vaccine Baits by Urban Raccoons

In summer 1986, a study was conducted to evaluate raccoon (Procyon lotor) acceptance of oral baits that could be used for rabies vaccination, One thousand wax-coated sponge bait cubes were filled with 5 mg of a seromarker (iophenoxic acid), placed in polyethylene bags, and hand-distributed in an 80 ha area within an urban National Park in Washington, D.C. (USA), After 3 wk, target and nontarget animals were trapped and blood samples collected to evaluate bait uptake. Thirty-three of 52 (63%) raccoons had elevated blood iodine levels indicating they had eaten at least one bait, 13 (25%) were negative, and six (12%) had marginal values, These results indicate that sponge baits hand-placed at a density of 12,4/ha can reach a significant proportion of an urban raccoon population. Implications for oral rabies vaccination of raccoons are discussed

Estrogen and Progestogen Correlates of the Structure of Female Copulation Calls in Semi-Free-Ranging Barbary Macaques (Macaca sylvanus)

Females of many Old World primates produce conspicuous vocalizations in combination with copulations. Indirect evidence exists that in Barbary macaques (Macaca sylvanus), the structure of these copulation calls is related to changes in reproductive hormone levels. However, the structure of these calls does not vary significantly around the timing of ovulation when estrogen and progestogen levels show marked changes. We here aimed to clarify this paradox by investigating how the steroid hormones estrogen and progesterone are related to changes in the acoustic structure of copulation calls. We collected data on semi-free-ranging Barbary macaques in Gibraltar and at La Forêt des Singes in Rocamadour, France. We determined estrogen and progestogen concentrations from fecal samples and combined them with a fine-grained structural analysis of female copulation calls (N = 775 calls of 11 females). Our analysis indicates a time lag of 3 d between changes in fecal hormone levels, adjusted for the excretion lag time, and in the acoustic structure of copulation calls. Specifically, we found that estrogen increased the duration and frequency of the calls, whereas progestogen had an antagonistic effect. Importantly, however, variation in acoustic variables did not track short-term changes such as the peak in estrogen occurring around the timing of ovulation. Taken together, our results help to explain why female Barbary macaque copulation calls are related to changes in hormone levels but fail to indicate the fertile phase

Investigating determinants of yawning in the domestic (Equus caballus) and Przewalski (Equus ferus przewalskii) horses

International audienceYawning is rare in herbivores which therefore may be an interesting group to disentangle the potential function(s) of yawning behaviour. Horses provide the opportunity to compare not only animals living in different conditions but also wild versus domestic species. Here, we tested three hypotheses by observing both domestic and Przewalski horses living in semi-natural conditions: (i) that domestic horses may show an elevated rate of yawning as a result of the domestication process (or as a result of life conditions), (ii) that individuals experiencing a higher level of social stress would yawn more than individuals with lower social stress and (iii) that males would yawn more often than females. The study involved 19 Przewalski horses (PHs) and 16 domestic horses (DHs) of different breeds living in large outdoor enclosures. The results showed that there was no difference between the PH and DH in yawning frequency (YF). PHs exhibited much higher levels of social interactions than DHs. There was a positive correlation between yawning frequency and aggressive behaviours in PHs, especially males, supporting the idea that yawning may be associated with more excitatory/stressful social situations. A correlation was found between yawning frequency and affiliative behaviours in DHs, which supports the potential relationship between yawning and social context. Finally, the entire males, but not castrated males, showed much higher levels of yawning than females in both species. The intensity (rather than the valence) of the interaction may be important in triggering yawning, which could therefore be a displacement activity that helps reduce tension

Testing the arousal hypothesis of neonatal imitation in infant rhesus macaques

Neonatal imitation is the matching of (often facial) gestures by newborn infants. Some studies suggest that performance of facial gestures is due to general arousal, which may produce false positives on neonatal imitation assessments. Here we examine whether arousal is linked to facial gesturing in newborn infant rhesus macaques (Macaca mulatta). We tested 163 infants in a neonatal imitation paradigm in their first postnatal week and analyzed their lipsmacking gestures (a rapid opening and closing of the mouth), tongue protrusion gestures, and yawn responses (a measure of arousal). Arousal increased during dynamic stimulus presentation compared to the static baseline across all conditions, and arousal was higher in the facial gestures conditions than the nonsocial control condition. However, even after controlling for arousal, we found a condition-specific increase in facial gestures in infants who matched lipsmacking and tongue protrusion gestures. Thus, we found no support for the arousal hypothesis. Consistent with reports in human newborns, imitators’ propensity to match facial gestures is based on abilities that go beyond mere arousal. We discuss optimal testing conditions to minimize potentially confounding effects of arousal on measurements of neonatal imitation

URBAN GRAY SQUIRREL DAMAGE AND POPULATION MANAGEMENT: A CASE HISTORY

Lafayette Park, a 3.0 hectare national park located across the street from the White House in Washington D.C., has had a gray squirrel (Sciurus carolinensis) density as high as 50 animals/hectare. In recent years this large population caused significant damage to mature trees and other vegetation. In keeping with the legislative mandate to protect and preserve the historic landscape in Lafayette Park, the National Park Service implemented a squirrel management program following an Integrated Pest Management (IPM) approach. The population was studied and monitored to determine the ecological bases for high squirrel numbers. Action was taken through a program of squirrel relocation and habitat modification to reduce available den sites. These programs were coordinated to minimize impact on the existing population, and continued monitoring has been used to evaluate efficacy. The implications of this program for resolving people-wildlife conflicts in urban environments are discussed

“Nuisance” Wildlife Control Trapping: Another Perspective

Urban wildlife control is a rapidly growing profession in which many practitioners apparently still come from a recreational or commercial trapping background. Perhaps for that reason, much of the “control” in resolving human-wildlife conflicts in cities and suburbs seems to revolve around the use of lethal traps to eliminate “problem” animals. Although some states allow relocation and most apparently allow for nuisance animals to be released on site, the extent to which these practices occur is little known. Further, the biological impacts of continual trapping cycles on urban wildlife populations remain little known as well. An alternative approach to trapping is to exclude problem animals, as is the generally accepted protocol with bats, taking care to avoid separating young from their mothers, or employing techniques to reunite mother and young through a carefully crafted reunion strategy. AAA Wildlife Control is a large wildlife control business based out of Toronto, Canada, that employs almost exclusively an exclusion-reunion strategy. This paper addresses the rationale for that approach and the general strategies the company uses for common problem species. Exclusion-reunion is arguably the most humane and biologically sound approach to wildlife conflict resolution, at least from the animal’s perspective, but questions will be raised about the potential transfer of “problems” from one site to another. These and other implications of this approach are raised and discussed based on multiple years of customer service

“Nuisance” Wildlife Control Trapping: Another Perspective

Urban wildlife control is a rapidly growing profession in which many practitioners apparently still come from a recreational or commercial trapping background. Perhaps for that reason, much of the “control” in resolving human-wildlife conflicts in cities and suburbs seems to revolve around the use of lethal traps to eliminate “problem” animals. Although some states allow relocation and most apparently allow for nuisance animals to be released on site, the extent to which these practices occur is little known. Further, the biological impacts of continual trapping cycles on urban wildlife populations remain little known as well. An alternative approach to trapping is to exclude problem animals, as is the generally accepted protocol with bats, taking care to avoid separating young from their mothers, or employing techniques to reunite mother and young through a carefully crafted reunion strategy. AAA Wildlife Control is a large wildlife control business based out of Toronto, Canada, that employs almost exclusively an exclusion-reunion strategy. This paper addresses the rationale for that approach and the general strategies the company uses for common problem species. Exclusion-reunion is arguably the most humane and biologically sound approach to wildlife conflict resolution, at least from the animal’s perspective, but questions will be raised about the potential transfer of “problems” from one site to another. These and other implications of this approach are raised and discussed based on multiple years of customer service

The “nuisance” wildlife control industry: animal welfare concerns

The recent and rapid growth of the private “nuisance” wildlife control industry follows the unparalleled current period of urban and suburban expansion. Nuisance wildlife control businesses range from simple home-based services to sophisticated franchised businesses. The nuisance wildlife control operator may hold an advanced degree in the wildlife sciences, or simply be an entrepreneur without formal education or even background experience in wildlife. State and federal agencies may participate directly or indirectly in nuisance wildlife control, in activities ranging from dissemination of advice or information to actual participation in programs that may lead to removal of animals. Naturally, all of the activities associated with nuisance wildlife control concern the many individuals and organizations in North America that are interested in animal welfare and protection. This paper addresses some of their concerns. We present a survey, summary, and critical analysis of the nuisance wildlife control industry with a special emphasis on what we view as its most problematic and troubling aspects. We discuss model standards, based primarily on existing best practices, and speculate about the future of this activity