Elevated glucocorticoids during the ovarian follicular phase predict conception in wild female chacma baboons.

Mating related behavior during ovarian cycling can be energetically demanding and constitute a significant stressor, requiring physiological responses to mediate investment in reproduction. To better understand the proximate mechanisms underlying these responses, we examine hormonal and behavioral variation across the ovarian cycle during conceptive and nonconceptive cycles in wild female chacma baboons (Papio ursinus). We quantified immunoreactive fecal estradiol, progesterone, and cortisol metabolites for 21 adult females, and calculated activity budgets and rates of received aggression from over 5000 15-min behavioral samples. We found conception to be associated with higher concentrations of both estradiol and cortisol during the follicular phase, but no difference in progesterone between conceptive and nonconceptive cycles for either the follicular or luteal phase. While females spent less time feeding during the follicular compared to the luteal phase, we found no difference in time spent feeding, moving, or copulating between conceptive and nonconceptive cycles of the same phase. Rates of received aggression also were similar across the ovarian cycle, with no difference between conceptive and nonconceptive cycles. Finally, we found positive associations between cortisol and estradiol, indicating that glucocorticoids (GCs) do not suppress hypothalamic-pituitary-gonadal (HPG) activity and reproductive function in this context. Overall, our results suggest that elevated GCs may play an adaptive role in mobilizing energy during sexually receptive periods of ovarian cycling.

Social status and helminth infections in female forest guenons (Cercopithecus mitis).

OBJECTIVE: When resource competition within primate social groups is effective, high-ranking individuals generally gain fitness benefits. Contrary to expectations, female Cercopithecus mitis form linear dominance hierarchies without evidence for rank-related variation in fitness-relevant measures, raising questions about the evolution of guenon social structure. Here, we test whether social status predicts gastrointestinal helminth infections, known to influence health and morbidity in other mammalian hosts. In addition, we assess whether infections contribute to stress responses as indicated by fecal glucocorticoid (fGC) levels. METHODS: We quantified infections and hormone levels in 382 fecal samples from 11 adult female Sykes' monkeys (C. m. albogularis) over four months in one wild study group at Gede Ruins, Kenya. Using a generalized estimating equations technique, we modeled the odds of infection, relative infection intensity, and fGC variation. RESULTS: High-ranking females were less likely infected with Trichuris and Trichostrongylus, had lower fecal egg counts for both taxa, and overall lower helminth richness than low-ranking females. An inverse relationship between rank and Trichuris egg counts existed also in a study population of blue monkeys (C. m. stuhlmanni), where we collected comparable data over a shorter period. Regardless of rank, lactating females were more likely than non-lactating females to be infected with Trichuris, and had higher fecal egg counts for both Trichuris and Oesophagostomum. Lastly, we report evidence that Trichuris infections exacerbated energetic stress and that food supplementation by tourists increased infection levels. CONCLUSION: Our findings suggest that high-rank may provide long-term health and energetic benefits for female C. mitis, with potential fitness implications.

Mean fecal glucocorticoid metabolites are associated with vigilance, whereas immediate cortisol levels better reflect acute anti-predator responses in meerkats.

Adrenal hormones likely affect anti-predator behavior in animals. With experimental field studies, we first investigated associations between mean fecal glucocorticoid metabolite (fGC) excretion and vigilance and with behavioral responses to alarm call playbacks in free-ranging meerkats (Suricata suricatta). We then tested how vigilance and behavioral responses to alarm call playbacks were affected in individuals administered exogenous cortisol. We found a positive association between mean fGC concentrations and vigilance behavior, but no relationship with the intensity of behavioral responses to alarm calls. However, in response to alarm call playbacks, individuals administered cortisol took slightly longer to resume foraging than control individuals treated with saline solution. Vigilance behavior, which occurs in the presence and absence of dangerous stimuli, serves to detect and avoid potential dangers, whereas responses to alarm calls serve to avoid immediate predation. Our data show that mean fGC excretion in meerkats was associated with vigilance, as a re-occurring anti-predator behavior over long time periods, and experimentally induced elevations of plasma cortisol affected the response to immediate threats. Together, our results indicate an association between the two types of anti-predator behavior and glucocorticoids, but that the underlying mechanisms may differ. Our study emphasizes the need to consider appropriate measures of adrenal activity specific to different contexts when assessing links between stress physiology and different anti-predator behaviors.

"Mayday mayday mayday", the millennium ark is sinking!

Despite exceptional advances in ensuring the health and well-being of animals in human care, zoos of the twenty-first century are ill-prepared and overwhelmed by the sheer number of species requiring conservation support. Furthermore, small population management paradigms have failed to achieve the demographic and genetic targets required to sustain most endangered species in human care. Predictions made in the 1980s regarding the potential of a "millennium ark"-aided by the use of assisted reproductive technologies (ARTs)-for saving species have proven to be wildly over-optimistic. ARTs continue to be touted as a panacea for saving endangered species and even for resurrecting extinct ones. And yet, while the first successful interspecies embryo transfer in a wildlife species occurred 30 years ago, there still is not a single example of embryo-based technologies being used to consistently manage a conservation-reliant species. The limited contribution of ARTs to species conservation to date principally stems from the lack of knowledge of species biology, as well as inadequate facilities, space, expertise, and funding needed for their successful application. ARTs could and should be an important tool in our conservation toolbox, but we cannot fall into the trap of believing that we can "assist" or clone our way out of the present biodiversity crisis. Reproductive technologists overstate the potential of ARTs for saving endangered species, zoos overestimate their ability to sustain genetically and demographically viable captive populations with existing resources, and conservationists underestimate their need for zoos in the face of failing efforts to sustain species in nature. Unless all parties concerned-reproductive technologists, zoo biologists and conservationists-adopt parallel efforts to sustain wild populations and places, zoos risk becoming living museums exhibiting relic species that no longer exist in nature.

FAIR Island: real-world examples of place-based open science.

The relationship between people, place, and data presents challenges and opportunities for science and society. While there has been general enthusiasm for and work toward Findable, Accessible, Interoperable, and Reusable (FAIR) data for open science, only more recently have these data-centric principles been extended into dimensions important to people and place-notably, the CARE Principles for Indigenous Data Governance, which affect collective benefit, authority to control, responsibility, and ethics. The FAIR Island project seeks to translate these ideals into practice, leveraging the institutional infrastructure provided by scientific field stations. Starting with field stations in French Polynesia as key use cases that are exceptionally well connected to international research networks, FAIR Island builds interoperability between different components of critical research infrastructure, helping connect these to societal benefit areas. The goal is not only to increase reuse of scientific data and the awareness of work happening at the field stations but more generally to accelerate place-based research for sustainable development. FAIR Island works reflexively, aiming to scale horizontally through networks of field stations and to serve as a model for other sites of intensive long-term scientific study.

Abnormal reproductive patterns in Przewalski's mares are associated with a loss in gene diversity.

The ex situ population of the Przewalski's horse (Equus ferus przewalskii) is not self-sustaining (20% foaling rate), and the demography is skewed toward aging individuals with low gene diversity. We designed the present study to gain a better understanding of the reproductive biology of the Przewalski's mare and to determine whether age and gene diversity influenced reproductive function. Urine samples were collected 3-7 days/wk from 19 mares from May to September, and ultrasound examinations of follicular structures were performed 3 days/wk for 5 wk from May through July in nine individuals. A high proportion of mares exhibited abnormal (endocrine, 5 [26.3%] of 19; follicular, 2 [22.2%] of 9) or acyclic (endocrine, 4 [21.1%] of 19; follicular, 3 [33.3%] of 9) reproductive patterns. In four cyclic mares, estrous cycle length was 25.1 ± 1.2 days, with 12.2 ± 0.9 days of diestrus. Follicles in cyclic mares grew 1.2 ± 0.6 mm per day and ovulated after reaching 40.4 ± 8.9 mm. Mares with a high coefficient of inbreeding excreted reduced levels of mean urinary estrogens (r(2) = 0.476, P < 0.05), but age had no significant impact on reproductive patterns in this population. Overall, these data suggest that long-term genetic management of this population is necessary to maintain reproductive fitness.

Reproductive rate, not dominance status, affects fecal glucocorticoid levels in breeding female meerkats.

Glucocorticoid hormones (GCs) have been studied intensively to understand the associations between physiological stress and reproductive skew in animal societies. However, we have little appreciation of the range of either natural levels within and among individuals, or the associations among dominance status, reproductive rate and GCs levels during breeding. To address these shortcomings, we examined variation in fecal glucocorticoid metabolites (fGC) during breeding periods in free-ranging female meerkats (Suricata suricatta) over 11 years. The vast majority of variation in fGC levels was found within breeding events by the same female (~87%), with the remaining variation arising among breeding events and among females. Concentrations of fGC generally tripled as pregnancy progressed. However, females with a high reproductive rate, defined as those conceiving within a month following parturition (mean = 9 days postpartum), showed significant reductions in fGC in the final 2 weeks before parturition. Despite these reductions, females with a high reproductive rate had higher fGC levels at conception of the following litter than those breeding at a low rate. After controlling for the higher reproductive rate of dominants, we found no association between levels of fGC and either age or dominance status. Our results suggest that one should be cautious about interpreting associations between dominance status, reproductive skew and GCs levels, without knowledge of the natural variation in GCs levels within and among females.

Adrenal activity and anxiety-like behavior in fur-chewing chinchillas (Chinchilla lanigera).

Due to its complexity, in combination with a lack of scientific reports, fur-chewing became one of the most challenging behavioral problems common to captive chinchillas. In the last years, the hypothesis that fur-chewing is an abnormal repetitive behavior and that stress plays a role in its development and performance has arisen. Here, we investigated whether a relationship existed between the expression and intensity of fur-chewing behavior, elevated urinary cortisol excretion and anxiety-related behaviors. Specifically, we evaluated the following parameters in behaviorally normal and fur-chewing animals of both sexes: (1) mean concentrations of urinary cortisol metabolites and (2) anxiety-like behavior in an elevated plus-maze test. Urinary cortisol metabolites were higher only in females that expressed the most severe form of the fur-chewing behavior (P≤0.05). Likewise, only fur-chewing females exhibited increased (P≤0.05) anxiety-like behaviors associated with the elevated plus-maze test. Overall, these data provided additional evidence to support the concept that fur-chewing is a manifestation of physiological stress in chinchilla, and that a female sex bias exists in the development of this abnormal behavior.

Testes size, testosterone production and reproductive behaviour in a natural mammalian mating system.

1. Testosterone (T) is a key mediator in the expression of numerous morphological and behavioural traits in mammals, but the factors underlying individual variation in circulating T levels are poorly understood. 2. The intimate structural integration of sperm and T production within the testes, alongside the dependency of sperm production on high levels of T, suggests that T requirements for spermatogenesis could be an important driver of individual differences in T. 3. To test this hypothesis, we examine how male capacity for sperm production (as indicated by their testes size) is associated with T levels in a feral population of Soay sheep, resident on St. Kilda, Scotland, during their rutting season. 4. We found a strong positive relationship between an individual's testes size (as measured before their seasonal enlargement) and the levels of circulating T during their rut, suggesting that T requirements for spermatogenesis has a prominent influence on the production of this androgen. 5. In contrast, body condition and competitive ability did not independently predict T levels, findings that are inconsistent with conventional 'condition-dependent' and 'challenge' hypotheses of T production. 6. This influence of male's capacity for sperm production on T appeared to be substantial enough to be biologically relevant, as testes size also predicted male aggression and mate-seeking behaviour. 7. Our results suggest that a male's inherent capacity for sperm and T production is tightly phenotypically integrated, with potential consequences for a wide range of other T-mediated reproductive traits.