FEMALE COMPETITION AND THE ROLE OF TESTOSTERONE IN A POLYGYNOUS SYSTEM

Testosterone plays an important role in male competitive ability, and it may play a similar function in females. Female-female competition for resources is often associated with high testosterone, both within females and in comparison to males. Positive associations between testosterone and competition are most likely to be seen in systems with high female-female competition. Resource defense polygyny may be one such system since females congregate on high-quality nutrient sources, leading to substantial opportunities for interference competition. I studied female Grant’s gazelle (Nanger granti), a classic resource defense polygynous species, to investigate female competition and its relationship to testosterone. I found substantial evidence for competition between females. Females frequently engaged in agonistic behavior, on average initiating over two agonistic bouts per hour, and higher-ranking females initiated more agonism than lower-ranking females. Testosterone appeared to play an important role in competitive ability. Immunoreactive fecal testosterone metabolites (fT) were strongly positively correlated to both dominance rank and number of agonistic bouts initiated per hour, but only agonism was associated with fT when dominance and agonism were accounted for simultaneously. Females had similar fT concentrations as males. fT was positively associated with immunoreactive fecal glucocorticoid metabolites (fGCM), and this relationship was not due to associations between dominance and fGCM. Month also influenced testosterone physiology. Females had lower fT during a drought than after rains had begun. In addition, fT increased more from August to November in high-ranking females than in low-ranking females. My results suggest that female-female competition may be substantial in resource defense polygynous systems. Testosterone might play an important role in mediating competitive ability in females, but it was also associated with higher glucocorticoid secretion. Future studies on females would be well served to investigate the consequences of testosterone secretion and how they relate to female competition

CORE ZONES, LIVESTOCK AND POPULATION ECOLOGY OF ARGALI IN MONGOLIA’S GOBI STEPPE

Core zones are established to reduce anthropogenic disturbance under the assumption that they protect biodiversity, yet this assumption has rarely been tested. In Central Asia, increasing livestock density threatens 70% of large mammals including in protected areas where livestock often constitute ~95% of ungulate biomass. A resulting conundrum is that local pastoralists are both key threats and crucial allies to conservation. Core zones, which reduce disturbance in small areas of important habitat, offer a potential solution to support wildlife and indigenous livelihoods. For my dissertation, I capitalize on a manipulation spanning 12 years to evaluate wild argali sheep (Ovis ammon) responses to reducing livestock density by 40% inside a core zone in Mongolia’s Gobi steppe. I investigate direct and indirect pathways through which pastoralists affect argali; quantify effects of livestock reduction on argali birth mass, survival, and population growth; and improve methods for monitoring argali populations throughout Central Asia. Because pastoralists influence plant, herbivore, and predator communities, they can affect argali through diverse pathways. Pastoralists alter predation pressure from both native and introduced carnivores, and their livestock probably compete with argali for food. I found that livestock reduction strongly affected argali, increasing argali birth mass by 18%, increasing juvenile survival from pre-reduction 19% to post-reduction 51%, and increasing argali population growth by 9% annually from 0.91 to 1.00. I found clear signals that argali are resource limited, since livestock reduction plus normalized difference vegetation index (NDVI) explained 97% of the annual variation in cohort lamb survival and explained 90% of the annual variation in asymptotic population growth. My analyses therefore reveal that livestock detrimentally affect argali and simultaneously provide empirical evidence that core zones can mitigate these effects. I also develop methods for monitoring argali populations using lamb:ewe ratios, from which I can infer population trend if adult survival at my study site is incorporated as a ceiling that can be attained but not surpassed at other locations. Lamb:ewe ratios are simple, inexpensive and can engage local communities in conservation efforts. In totality my dissertation advances conservation of argali while broadly yielding insight on a complex ecological process, interspecific competition

Multi-Objective Modeling as a Decision-Support Tool for Free-Roaming Horse Management

Decisions related to controversial problems in natural resource management receive the greatest support when they account for multiple objectives of stakeholders in a structured and transparent fashion. In the United States, management of free-roaming horses (Equus caballus; horses) is a controversial multiple-objective problem because disparate stakeholder groups have varying objectives and opinions about how to manage fast-growing horse populations in ways that sustain both natural ecosystems and healthy horses. Despite much decision-support research on management alternatives that prevent excessive population size or cost, horse management decisions still receive resistance from a variety of stakeholder groups, potentially because decisions fail to explicitly or transparently account for multiple objectives of diverse stakeholders. Here, we used a predictive model for horse populations to evaluate the degree to which alternative management strategies involving removals and fertility control treatment with the immunocontraceptive vaccine PZP-22 maximize 4 objectives in horse management: maximize ecosystem health, maximize horse health, minimize effects on horse behavior, and minimize management cost. We simulated scenarios varying in management action, frequency, magnitude, and starting population size over a 10-year interval and evaluated scenario performance with a weighted multiple-objective utility reward function. Management involving high-magnitude removals along with PZP-22 treatment generally outperformed other alternatives by achieving higher reward relative to alternatives in 2 scenario analyses. Simulation of 1,372 scenarios at 5 starting population sizes generally found that management with biannual removals and 2 doses of PZP-22 treatment for half of eligible females during years 1 and 5 generated the most rewarding outcomes. However, a removal scenario with more frequent PZP-22 application generated the greatest reward when starting population size was already within target population size range. Our paper demonstrates how values and objectives of diverse stakeholders can be used to support management decisions in ways that might lead to greater acceptance of decisions by a broad array of stakeholder groups

Emerging Tools to Control Feral Horse Populations in the Western USA

The U.S. Geological Survey (USGS) has been conducting research to support the Bureau of Land Management (BLM) Wild Horse and Burro Program since 1996 and is currently engaged in testing additional tools to curb high population growth of feral horses. Horses are protected by the Wild and Free-Roaming Horses and Burros Act of 1971 and are managed to maintain populations at appropriate management level (AML). With no natural predators, many populations double in 4-5 years. Population size is controlled primarily with “gathers” in which horses are rounded up and made available for adoption by the public. This is a costly enterprise in which animals are housed in holding facilities while they await potential adoption and many horses are never adopted. Today ~48,000 horses remain in holding facilities across the USA, and facilities are now full. There are approximately 72,000 horses on public lands across the west, which is almost 3 times range wide AML. Horses have profound impacts on habitat and other wildlife, and the situation is becoming critical on western landscapes. With holding facilities at capacity, BLM is forced to leave excess animals on public lands, leading to rangeland degradation and impacts to sage grouse and other wildlife. Solutions are needed quickly to address exponential population growth of horses. USGS partnered with Oklahoma State University (OSU) and Colorado State University (CSU), respectively, to conduct studies testing the efficacy of intrauterine devices (IUD) for horses, and gelding a proportion of males in a population. The IUD study was conducted on 20 domestic mares that were housed with stallions at OSU. Fifteen mares retained IUDs for the 18-month duration of the trial before IUDs were removed. Mares who received progesterone at the time of IUD insertion retained their IUDs, and no mares with an IUD became pregnant. Next we will test IUDs in free-roaming mares. In the gelding study with CSU, there were no differences in individual behavior or movement rates between gelded and non-gelded harem stallions or bachelors after the first breeding season. Gelded harem stallions did not lose their mares at a higher rate than intact stallions, and mares joined gelded harem stallions as often as they joined intact stallions. Preliminary results indicate little if any change to social structure or individual behavior of stallions or mares compared to controls. We will determine after the summer 2019 birthing season if gelding males affects population growth rate. USGS proposed a field study to determine behavior and population growth reduction of sterilizing mares but the study was litigated and postponed. Modeling by USGS indicates sterilization is the most effective and promising tool to reduce herds to AML and would potentially save BLM \u3e$1 billion annually in direct operational costs. The environmental cost to habitat and other wildlife associated with keeping excess horses on the range, as well as direct economic costs, have not yet been calculated for comparison

Patient characteristics of the Accident and Emergency Department of Kenyatta National Hospital, Nairobi, Kenya: a cross-sectional, prospective analysis

Background Resource-limited settings are increasingly experiencing a ‘triple burden’ of disease, composed of trauma, non-communicable diseases (NCDs) and known communicable disease patterns. However, the epidemiology of acute and emergency care is not well characterised and this limits efforts to further develop emergency care capacity. Objective To define the burden of disease by describing the patient population presenting to the Accident and Emergency Department (A&E) at Kenyatta National Hospital (KNH) in Kenya. Methods We completed a prospective descriptive assessment of patients in KNH’s A&E obtained via systematic sampling over 3 months. Research assistants collected data directly from patients and their charts. Chief complaint and diagnosis codes were grouped for analysis. Patient demographic characteristics were described using the mean and SD for age and n and percentages for categorical variables. International Classification of Disease 10 codes were categorised by 2013 Global Burden of Disease Study methods. Results Data were collected prospectively on 402 patients with an average age of 36 years (SD 19), and of whom, 50% were female. Patients were most likely to arrive by taxi or bus (39%), walking (28%) or ambulance (17%). Thirty-five per cent of patients were diagnosed with NCDs, 24% with injuries and 16% with communicable diseases, maternal and neonatal conditions. Overall, head injury was the single most common final diagnosis and occurred in 32 (8%) patients. The most common patient-reported mechanism for head injury was road traffic accident (39%). Conclusion This study estimates the characteristics of the A&E population at a tertiary centre in Kenya and highlights the triple burden of disease. Our findings emphasise the need for further development of emergency care resources and training to better address patient needs in resource-limited settings, such as KNH

Retrospective Review of the Patient Cases at a Major Trauma Center in Nairobi, Kenya and Implications for Emergency Care Development

Introduction Low- and middle-income countries (LMICs) are continuing to experience a “triple burden” of disease - traumatic injury, non-communicable diseases (NCDs), and communicable disease with maternal and neonatal conditions (CD&Ms). The epidemiology of this triad is not well characterised and poses significant challenges to resource allocations, administration, and education of emergency care providers. The data collected in this study provide a comprehensive description of the emergency centre at Kenya\u27s largest public tertiary care hospital. Methods This study is a retrospective chart review conducted at Kenyatta National Hospital of all patient encounters over a four-month period. Data were collected from financial and emergency centre triage records along with admission and mortality logbooks. Chief complaints and discharge diagnoses collected by specially trained research assistants were manually converted to standardised diagnoses using International Classification of Disease 10 (ICD-10) codes. ICD-10 codes were categorised into groups based on the ICD-10 classification system for presentation. Results A total of 23,941 patients presented to the emergency centre during the study period for an estimated annual census of 71,823. The majority of patients were aged 18-64 years (58%) with 50% of patients being male and only 3% of unknown sex. The majority of patients (61%) were treated in the emergency centre, observed, and discharged home. Admission was the next most common disposition (33%) followed by death (6%). Head injury was the overall most common diagnosis (11%) associated with admission. Conclusions Trends toward NCDs and traumatic diseases have been described by this study and merit further investigation in both the urban and rural setting. Specifically, the significance of head injury on healthcare cost, utilisation, and patient death and disability points to the growing need of additional resources at Kenyatta National Hospital for acute care. It further demonstrates the mounting impact of trauma in Kenya and throughout the developing world

Sex and age differences in juvenile social priorities in female philopatric, nondespotic blue monkeys

Juveniles should choose social partners on the basis of both current and future utility. Where one sex is philopatric, one expects members of that sex to develop greater and sex-typical social integration with group-mates over the juvenile period. Where a partner's position in a dominance hierarchy is not associated with services it can provide, one would not expect juveniles to choose partners based on rank, nor sex differences in rank-based preferences. We tested these ideas on 39 wild juvenile (3.2–7.4 years) blue monkeys ( Cercopithecus mitis stuhlmanni), cercopithecines with strict female philopatry and muted hierarchies. We made focal animal observations over 6 months, and computed observed:expected amounts of proximity time, approaches and grooming given to various social partners. Overall, our results agree with the hypothesis that juvenile blue monkeys target social partners strategically. Spatial proximity, approaches and active grooming showed similar patterns regarding juvenile social preferences. Females were far more sociable than males, groomed more partners, reciprocated grooming more frequently, and preferred—while males avoided—infants as partners. Older juveniles (5–7 years) spent more time than younger juveniles (3–4 years) near others, and older females were especially attracted to infants. Close kin, especially mothers and less consistently adult sisters, were attractive to both male and female juveniles, regardless of age. Both sexes also preferred same-sex juveniles as social partners while avoiding opposite-sex peers. Juveniles of both sexes and ages generally neither preferred nor avoided nonmaternal adult females, but all juveniles avoided adult males. Partner's rank had no consistent effect on juveniles' preference, as expected for a species in which dominance plays a weak role. Juveniles' social preferences likely reflect both future and current benefits, including having tolerant adult kin to protect them against predators and conspecifics, same-sex play partners, and, for females, infants on which to practice mothering skills. Am. J. Primatol. 72:193–205, 2010. © 2009 Wiley-Liss, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/64898/1/20768_ftp.pd