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Large carnivores have been largely extirpated from Southeast Asia due to deforestation, habitat fragmentation, and poaching. Estimating the density of endangered carnivore populations, and identifying relationships between species occupancy and both environmental and anthropogenic factors, is essential for effective conservation planning. Recently, the IUCN conservation status of the Indochinese leopard (Panthera pardus delacouri) was upgraded to "Critically Endangered. " We surveyed Kweekoh Wildlife Sanctuary in Kawthoolei, an area administered by the Karen ethnic group in eastern Myanmar, to quantify (1) leopard population density using spatially explicit mark-resight (SMR) models, (2) leopard occupancy as influenced by important ecological variables, and (3) potential differences in activity between melanistic and spotted leopard morphs. Leopard density was estimated to be 1.39 +/- SE 0.22/100 km(2). Leopard occupancy (psi = 0.43; 95% credible interval: 0.26-0.67) increased further from roads, at relatively higher elevations, and in areas with higher relative abundance of wild boar. Leopard activity was cathemeral, with higher activity during night hours, and significant overlap (delta = 0.84; 95% confidence interval: 0.71-0.96) between melanistic and spotted morphs. However, melanistic leopards were more active during twilight hours than spotted individuals whose activity did not significantly vary throughout the day. Indochinese leopard density estimates in Kweekoh were among the lowest reported from Southeast Asia. Leopard occupancy was highest in the sanctuary's core areas, suggesting the presence of negative anthropogenic impacts along the sanctuary borders. We suggest our low density estimates warrant immediate and decisive conservation action, including better protection for leopards, their habitat, and their prey.

Maintaining landscape connectivity for large felids by preserving and restoring corridors between core habitats is crucial to their long-term conservation. Tiger, leopard, and clouded leopard populations occur in isolated habitat patches across the Dawna-Tanintharyi Landscape (DTL) of Kawthoolei (all Karen National Union administrative areas in Myanmar) and Thailand. We analyzed connectivity among 18 habitat patches in this transboundary region based on large felid presence and expert opinion of large felid dispersal requirements. Least-cost corridor and circuit theory analyses were used to identify corridors, determine corridor quality and their relative importance to connectivity in the landscape, and pinpoint bottlenecks to movement. Forty-eight corridors were identified. Lower resistances to dispersal were in forested montane areas. High-quality corridors remained in the northern DTL and south of Tanintharyi Nature Reserve in Kawthoolei based on cost-weighted distance to least-cost path ratio. Pairwise current pinch point analyses revealed a possible landscape level bottleneck to movement north of Thailand’s Western Forest Complex. Area corrected centrality scores indicated smaller habitat patches disproportionately contributed to landscape connectivity. The DTL may retain connectivity across the landscape if conservation actions are taken to protect integral habitats and corridors. Conservation efforts that expand the protected area network in Kawthoolei, either by increasing the size of current protected area habitats or by demarcating new protected areas in regions with confirmed felid presence, will aid DTL connectivity. The DTL should be managed to preserve connectivity on both sides of the border, entailing international governmental, indigenous community, and non-governmental collaboration.

Dietary restriction (DR), limiting calories or specific nutrients without malnutrition, extends lifespan across diverse taxa. Traditionally, this lifespan extension has been explained as a result of diet-mediated changes in the trade-off between lifespan and reproduction, with survival favoured when resources are scarce. However, a recently proposed alternative suggests that the selective benefit of the response to DR is the maintenance of reproduction. This hypothesis predicts that lifespan extension is a side effect of benign laboratory conditions, and DR individuals would be frailer and unable to deal with additional stressors, and thus lifespan extension should disappear under more stressful conditions. We tested this by rearing outbred female fruit flies (Drosophila melanogaster) on 10 different protein:carbohydrate diets. Flies were either infected with a bacterial pathogen (Pseudomonas entomophila), injured with a sterile pinprick or unstressed. We monitored lifespan, fecundity and measures of ageing. DR extended lifespan and reduced reproduction irrespective of injury and infection. Infected flies on lower protein diets had particularly poor survival. Exposure to infection and injury did not substantially alter the relationship between diet and ageing patterns. These results do not provide support for lifespan extension under DR being a side effect of benign laboratory conditions. This article is protected by copyright. All rights reserved.

The timing of volatile organic compound (VOC) emission by flowering plants often coincides with pollinator foraging activity. Volatile emission is often considered to be paced by environmental variables, such as light intensity, and/or by circadian rhythmicity. The question arises as to what extent pollinators themselves provide information about their presence, in keeping with their long co-evolution with flowering plants. Bumblebees are electrically charged and provide electrical stimulation when visiting plants, as measured via the depolarisation of electric potential in the stem of flowers. Here we test the hypothesis that the electric charge of foraging bumblebees increases the floral volatile emissions of bee pollinated plants. We investigate the change in VOC emissions of two bee-pollinated plants (Petunia integrifolia and Antirrhinum majus) exposed to the electric charge typical of foraging bumblebees. P. integrifolia slightly increases its emissions of a behaviorally and physiologically active compound in response to visits by foraging bumblebees, presenting on average 121 pC of electric charge. We show that for P. integrifolia, strong electrical stimulation (600–700 pC) promotes increased volatile emissions, but this is not found when using weaker electrical charges more representative of flying pollinators (100 pC). Floral volatile emissions of A. majus were not affected by either strong (600–700 pC) or weak electric charges (100 pC). This study opens a new area of research whereby the electrical charge of flying insects may provide information to plants on the presence and phenology of their pollinators. As a form of electroreception, this sensory process would bear adaptive value, enabling plants to better ensure that their attractive chemical messages are released when a potential recipient is present.

UK universities re-opened in September 2020, amidst the coronavirus epidemic. During the first term, various national social distancing measures were introduced, including banning groups of >6 people and the second lockdown in November; however, outbreaks among university students occurred. We aimed to measure the University of Bristol staff and student contact patterns via an online, longitudinal survey capturing self-reported contacts on the previous day. We investigated the change in contacts associated with COVID-19 guidance periods: post-first lockdown (23/06/2020–03/07/2020), relaxed guidance period (04/07/2020–13/09/2020), ‘rule-of-six’ period (14/09/2020–04/11/2020) and the second lockdown (05/11/2020–25/11/2020). In total, 722 staff (4199 responses) and 738 students (1906 responses) were included in the study. For staff, daily contacts were higher in the relaxed guidance and ‘rule-of-six’ periods than the post-first lockdown and second lockdown. Mean student contacts dropped between the ‘rule-of-six’ and second lockdown periods. For both staff and students, the proportion meeting with groups larger than six dropped between the ‘rule-of-six’ period and the second lockdown period, although was higher for students than for staff. Our results suggest university staff and students responded to national guidance by altering their social contacts. Most contacts during the second lockdown were household contacts. The response in staff and students was similar, suggesting that students can adhere to social distancing guidance while at university. The number of contacts recorded for both staff and students were much lower than those recorded by previous surveys in the UK conducted before the COVID-19 pandemic.

University students have unique living, learning and social arrangements which may have implications for infectious disease transmission. To address this data gap, we created CONQUEST (COroNavirus QUESTionnaire), a longitudinal online survey of contacts, behaviour, and COVID-19 symptoms for University of Bristol (UoB) staff/students. Here, we analyse results from 740 students providing 1261 unique records from the start of the 2020/2021 academic year (14/09/2020–01/11/2020), where COVID-19 outbreaks led to the self-isolation of all students in some halls of residences. Although most students reported lower daily contacts than in pre-COVID-19 studies, there was heterogeneity, with some reporting many (median = 2, mean = 6.1, standard deviation = 15.0; 8% had ≥ 20 contacts). Around 40% of students’ contacts were with individuals external to the university, indicating potential for transmission to non-students/staff. Only 61% of those reporting cardinal symptoms in the past week self-isolated, although 99% with a positive COVID-19 test during the 2 weeks before survey completion had self-isolated within the last week. Some students who self-isolated had many contacts (mean = 4.3, standard deviation = 10.6). Our results provide context to the COVID-19 outbreaks seen in universities and are available for modelling future outbreaks and informing policy.

IntroductionUK universities re-opened in September 2020, despite the on-going coronavirus epidemic. During the first term, various national social distancing measures were introduced, including banning groups of >6 people and the second lockdown in November. COVID-19 can spread rapidly in university-settings, and students’ adherence to social distancing measures is critical for controlling transmission.MethodsWe measured university staff and student contact patterns via an online, longitudinal survey capturing self-reported contacts on the previous day. We investigated the change in contacts associated with COVID-19 guidance periods: post-first lockdown (23/06/2020-03/07/2020), relaxed guidance period (04/07/2020-13/09/2020), “rule-of-six” period (14/09/2020-04/11/2020), and the second lockdown (05/11/2020-25/11/2020).Results722 staff (4199 responses) (mean household size: 2.6) and 738 students (1906 responses) (mean household size: 4.5) were included in the study. Contact number decreased with age. Staff in single-person households reported fewer contacts than individuals in 2-and 3-person households, and individuals in 4-and 5-person households reported more contacts.For staff, daily contacts were higher in the relaxed guidance and “rule-of-six” periods (means: 3.2 and 3.5, respectively; medians: 3) than the post-first lockdown and second lockdown periods (means: 4.5 and 5.4, respectively; medians: 2). Few students responded until 05/10/2020, after which the median student contacts was 2 and the mean was 5.7, until the second lockdown when it dropped to 3.1.DiscussionUniversity staff and students responded to national guidance by altering their social contacts. The response in staff and students was similar, suggesting that students are able to adhere to social distancing guidance while at university.

CONQUEST (COroNavirus QUESTionnaire) is an online survey of contacts, behaviour, and COVID-19 symptoms for University of Bristol (UoB) staff/students. We analysed survey results from the start of the 2020/2021 academic year, prior to the second national lockdown (14/09/2020-01/11/2020), where COVID-19 outbreaks led to lockdown of some student halls of residence. The aim of these analyses was to enhance knowledge of student contact patterns to inform infection disease mathematical modelling approaches.Responses captured information on demographics, contacts on the previous day, symptoms and self-isolation during the prior week, and COVID-19 status.740 students provided 1261 unique records. Of 42 (3%) students testing positive in the prior fortnight, 99% had been self-isolating. The median number of contacts on the previous day was 2 (interquartile range: 1-5), mode: 1, mean: 6.1; 8% had ≥20 contacts. 57% of student contacts were other UoB students/staff.Most students reported few daily contacts but there was heterogeneity, and some reported many. Around 40% of student contacts were with individuals not affiliated with UoB, indicating potential for transmission to non-students/staff.

Dietary restriction (DR), limiting calories or specific nutrients, extends lifespan across diverse taxa. This lifespan extension has been explained as diet-mediated changes in the trade-off between lifespan and reproduction, with survival favoured with scarce resources. Another evolutionary hypothesis suggests the selective benefit of the response is the maintenance of reproduction. This hypothesis predicts that lifespan extension is a side effect of benign laboratory conditions, where DR individuals are frailer and unable to deal with additional stressors, and thus lifespan extension should disappear under more stressful conditions. We tested this by rearing outbred female Drosophila melanogaster on 10 different protein:carbohydrate diets. Flies were either infected with a bacterial pathogen (Pseudomonas entomophila), injured or unstressed. We monitored lifespan, fecundity and ageing measures. DR extended lifespan and reduced reproduction irrespective of injury and infection. These results do not support lifespan extension under DR being a side effect of benign laboratory conditions.

Kawthoolei (defined as all Karen National Union administrative areas and encompassing Karen State, Myanmar), a global hotspot for biodiversity, is increasingly under threat due to deforestation, mining, human population growth, indiscriminate burning, and infrastructure development. Pinpointing biodiversity hotspots to focus conservation efforts is integral given the limited funding and capacity of local conservation actors to undertake activities throughout Kawthoolei. We obtained wildlife presence data for 23 medium-large mammal species of conservation concern from 7 years of camera trapping efforts throughout Kawthoolei and produced species distribution models, which were used to prioritize areas for conservation action. Presence only data were combined with bioclimatic, topographical, anthropogenic, land cover, and biotic interaction variables to produce Maxent models covering 87,612 km2. Species specific maps were weighted according to their IUCN Red List of Threatened Species status and combined to pinpoint areas with high biodiversity, weighing areas higher that harbored Vulnerable and Endangered species. Individual species were predicted present in 1.44–32.17 % of the study area. Priority maps classified 55.91 % of the total study area as having no species present, 25.07 % as low priority, 10.73 % as medium priority, and 8.29 % as high priority. The protected area system currently covers 26.8 % of the high priority habitats available. While most endemic species continue to persist in Kawthoolei, models demonstrated a scattered distribution of high priority areas throughout Kawthoolei, which may lack connectivity. Additional conservation actions that supplement the current protected area system may be necessary to curb extirpation risks, including the demarcation and active patrolling of additional protected areas in high priority landscapes and activities that promote connectivity between high-quality habitats.