Tracking large carnivore dispersal using isotopic clues in claws: An application to cougars across the Great Plains

1. Cougar (Puma concolor) populations, like other large carnivores, have increased during recent decades and may be recolonizing their former ranges in Midwestern North America. The dispersal routes taken by these animals from established populations are unknown and insight into these movements would facilitate their conservation and management. 2. We inferred the origin and migration route of four dispersing cougars using stable hydrogen (δD) and carbon (δ13C) isotope values along one of their claws. We compared isotopic variations within claws to regional and large-scale isoscapes of δD and δ13C values in prey species. Using a likelihood-based assignment approach, we predicted the most likely dispersal route of each cougar (among several least-cost dispersal paths to potential source populations) in a chronological sequence dating back from its final location. 3. Our model predicted the origin of a radio-collared short-distance disperser and inferences about the most likely dispersal corridors for two long-distance dispersers matched reported information from re-sighting events and genetic investigations. 4. Insights about the most likely migration corridors may help identify critical areas and guide future conservation efforts of cougars and other large carnivores. We encourage managers to extend regional isoscapes based on sedentary prey species as they prove to be valuable tools in isotopic tracking of long-distance migration. 5. Our isotopic approach may be extended to other metabolically inert tissues that grow continuously, to investigate dispersal paths of species of interest, providing that individuals disperse across known isotopically structured landscapes

A periodic network of neurochemical modules in the inferior colliculus

Abstract A new organization has been found in shell nuclei of rat inferior colliculus. Chemically specific modules with a periodic distribution fill about half of layer 2 of external cortex and dorsal cortex. Modules contain clusters of small glutamic acid decarboxylase-positive neurons and large boutons at higher density than in other inferior colliculus subdivisions. The modules are also present in tissue stained for parvalbumin, cytochrome oxidase, nicotinamide adenine dinucleotide phosphate-diaphorase, and acetylcholinesterase. Six to seven bilaterally symmetrical modules extend from the caudal extremity of the external cortex of the inferior colliculus to its rostral pole. Modules are from V800 to 2200 Wm long and have areas between 5000 and 40 000 Wm 2 . Modules alternate with immunonegative regions. Similar modules are found in inbred and outbred strains of rat, and in both males and females. They are absent in mouse, squirrel, cat, bat, macaque monkey, and barn owl. Modules are immunonegative for glycine, calbindin, serotonin, and choline acetyltransferase. The auditory cortex and ipsi-and contralateral inferior colliculi project to the external cortex. Somatic sensory influences from the dorsal column nuclei and spinal trigeminal nucleus are the primary ascending sensory input to the external cortex; ascending auditory input to layer 2 is sparse. If the immunopositive modular neurons receive this input, the external cortex could participate in spatial orientation and somatic motor control through its intrinsic and extrinsic projections.

An Emperor Penguin population estimate: The first global, synoptic survey of a species from space

Our aim was to estimate the population of emperor penguins (Aptenodytes fosteri) using a single synoptic survey. We examined the whole continental coastline of Antarctica using a combination of medium resolution and Very High Resolution (VHR) satellite imagery to identify emperor penguin colony locations. Where colonies were identified, VHR imagery was obtained in the 2009 breeding season. The remotely-sensed images were then analysed using a supervised classification method to separate penguins from snow, shadow and guano. Actual counts of penguins from eleven ground truthing sites were used to convert these classified areas into numbers of penguins using a robust regression algorithm. We found four new colonies and confirmed the location of three previously suspected sites giving a total number of emperor penguin breeding colonies of 46. We estimated the breeding population of emperor penguins at each colony during 2009 and provide a population estimate of ~238,000 breeding pairs (compared with the last previously published count of 135,000–175,000 pairs). Based on published values of the relationship between breeders and non-breeders, this translates to a total population of ~595,000 adult birds. There is a growing consensus in the literature that global and regional emperor penguin populations will be affected by changing climate, a driver thought to be critical to their future survival. However, a complete understanding is severely limited by the lack of detailed knowledge about much of their ecology, and importantly a poor understanding of their total breeding population. To address the second of these issues, our work now provides a comprehensive estimate of the total breeding population that can be used in future population models and will provide a baseline for long-term research

First observations of Weddell seals foraging in sponges in Erebus Bay, Antarctica

Attaching cameras to marine mammals allows for first-hand observation of underwater behaviours that may otherwise go unseen. While studying the foraging behaviour of 26 lactating Weddell seals (Leptonychotes weddellii) in Erebus Bay during the austral spring of 2018 and 2019, we witnessed three adults and one pup investigating the cavities of Rossellidae glass sponges, with one seal visibly chewing when she removed her head from the sponge. To our knowledge, this is the first report of such behaviour. While the prey item was not identifiable, some Trematomus fish (a known Weddell seal prey) use glass sponges for shelter and in which to lay their eggs. Three of the four sponge foraging observations occurred around 13:00 (NZDT). Two of the three sponge foraging adults had higher-than-average reproductive rates, and the greatest number of previous pups of any seal in our study population, each having ten pups in 12 years. This is far higher than the study population average of three previous pups (± 2.6 SD). This novel foraging strategy may have evolved in response to changes in prey availability, and could offer an evolutionary advantage to some individuals that exploit prey resources that others may not. Our observations offer new insight into the foraging behaviours of one of the world’s most studied marine mammals. Further research on the social aspects of Weddell seal behaviour may increase our understanding of the extent and mechanisms of behavioural transfer between conspecifics. Research into the specific foraging behaviour of especially successful or experienced breeders is also warranted

Climate Change Winners: Receding Ice Fields Facilitate Colony Expansion and Altered Dynamics in an Adélie Penguin Metapopulation

There will be winners and losers as climate change alters the habitats of polar organisms. For an Adelie penguin (Pygoscelis adeliae) colony on Beaufort Island (Beaufort), part of a cluster of colonies in the southern Ross Sea, we report a recent population increase in response to increased nesting habitat as glaciers have receded. Emigration rates of birds banded as chicks on Beaufort to colonies on nearby Ross Island decreased after 2005 as available habitat on Beaufort increased, leading to altered dynamics of the metapopulation. Using aerial photography beginning in 1958 and modern satellite imagery, we measured change in area of available nesting habitat and population size of the Beaufort colony. Population size varied with available habitat, and both increased rapidly since the 1990s. In accord with glacial retreat, summer temperatures at nearby McMurdo Station increased by similar to 0.50 degrees C per decade since the mid-1980s. Although the Ross Sea is likely to be the last ocean with an intact ecosystem, the recent retreat of ice fields at Beaufort that resulted in increased breeding habitat exemplifies a process that has been underway in the Ross Sea during the entire Holocene. Furthermore, our results are in line with predictions that major ice shelves and glaciers will retreat rapidly elsewhere in the Antarctic, potentially leading to increased breeding habitat for Adelie penguins. Results further indicated that satellite imagery may be used to estimate large changes in Adelie penguin populations, facilitating our understanding of metapopulation dynamics and environmental factors that influence regional populations

Evaluation of the current knowledge limitations in breast cancer research: a gap analysis

BACKGROUND A gap analysis was conducted to determine which areas of breast cancer research, if targeted by researchers and funding bodies, could produce the greatest impact on patients. METHODS Fifty-six Breast Cancer Campaign grant holders and prominent UK breast cancer researchers participated in a gap analysis of current breast cancer research. Before, during and following the meeting, groups in seven key research areas participated in cycles of presentation, literature review and discussion. Summary papers were prepared by each group and collated into this position paper highlighting the research gaps, with recommendations for action. RESULTS Gaps were identified in all seven themes. General barriers to progress were lack of financial and practical resources, and poor collaboration between disciplines. Critical gaps in each theme included: (1) genetics (knowledge of genetic changes, their effects and interactions); (2) initiation of breast cancer (how developmental signalling pathways cause ductal elongation and branching at the cellular level and influence stem cell dynamics, and how their disruption initiates tumour formation); (3) progression of breast cancer (deciphering the intracellular and extracellular regulators of early progression, tumour growth, angiogenesis and metastasis); (4) therapies and targets (understanding who develops advanced disease); (5) disease markers (incorporating intelligent trial design into all studies to ensure new treatments are tested in patient groups stratified using biomarkers); (6) prevention (strategies to prevent oestrogen-receptor negative tumours and the long-term effects of chemoprevention for oestrogen-receptor positive tumours); (7) psychosocial aspects of cancer (the use of appropriate psychosocial interventions, and the personal impact of all stages of the disease among patients from a range of ethnic and demographic backgrounds). CONCLUSION Through recommendations to address these gaps with future research, the long-term benefits to patients will include: better estimation of risk in families with breast cancer and strategies to reduce risk; better prediction of drug response and patient prognosis; improved tailoring of treatments to patient subgroups and development of new therapeutic approaches; earlier initiation of treatment; more effective use of resources for screening populations; and an enhanced experience for people with or at risk of breast cancer and their families. The challenge to funding bodies and researchers in all disciplines is to focus on these gaps and to drive advances in knowledge into improvements in patient care

Improving metabolic health in obese male mice via diet and exercise restores embryo development and fetal growth

Paternal obesity is now clearly associated with or causal of impaired embryo and fetal development and reduced pregnancy rates in humans and rodents. This appears to be a result of reduced blastocyst potential. Whether these adverse embryo and fetal outcomes can be ameliorated by interventions to reduce paternal obesity has not been established. Here, male mice fed a high fat diet (HFD) to induce obesity were used, to determine if early embryo and fetal development is improved by interventions of diet (CD) and/or exercise to reduce adiposity and improve metabolism. Exercise and to a lesser extent CD in obese males improved embryo development rates, with increased cell to cell contacts in the compacting embryo measured by E-cadherin in exercise interventions and subsequently, increased blastocyst trophectoderm (TE), inner cell mass (ICM) and epiblast cell numbers. Implantation rates and fetal development from resulting blastocysts were also improved by exercise in obese males. Additionally, all interventions to obese males increased fetal weight, with CD alone and exercise alone, also increasing fetal crown-rump length. Measures of embryo and fetal development correlated with paternal measures of glycaemia, insulin action and serum lipids regardless of paternal adiposity or intervention, suggesting a link between paternal metabolic health and subsequent embryo and fetal development. This is the first study to show that improvements to metabolic health of obese males through diet and exercise can improve embryo and fetal development, suggesting such interventions are likely to improve offspring health.Nicole O. McPherson, Hassan W. Bakos, Julie A. Owens, Brian P. Setchell, Michelle Lan

Food Habits of the Hoary Bat (Lasiurus cinereus) in Southwestern Minnesota

The hoary bat is one of the most widespread bats in North America and is the largest bat found in the state of Minnesota. However, little of the natural history is known for this species due to its solitary, tree-roosting, and lowdensity lifestyle. As part of a larger project, more than 100 hoary bat carcasses were collected during the summers of 2000-2002 at the Buffalo Ridge Wind Resource Area in southwestern Minnesota. This collection was very large and provided a unique and important opportunity to examine the food habits of the hoary bat. Gastrointestinal tracts were dissected from all bats that were not in late stages of decomposition. Contents of the stomach and fecal pellets were sorted and identified to Family by comparing the fragments in the samples to insects that were sampled and collected in the study area. There were 25 bats that were in suitable condition for examination. Preliminary data suggests that hoary bats in southwestern Minnesota feed on members of Class Insecta, primarily from Order Lepidoplera (butterflies and moths), Order Coleoptera (beetles), and Order Hemiptera (true bugs). These results are consistent with the limited reports for this species from other geographic regions

Using Distance Sampling to Estimate Densities of Deer in Minnesota\u27s Farmland Region

Estimation of the size of the white-tailed deer (Odocoileus virginianus) population is essential for proper management of the deer herd. Further, a survey of wildlife managers indicated that improved techniques were needed to monitor deer populations in Minnesota\u27s farmland region. We evaluated a new method, distance sampling, in an effort to identify a more accurate and efficient method of estimating the size of deer populations. Distance sampling is an increasingly popular method of estimating the size of animal populations due to its accuracy and logistical advantages relative to other methods. In this pilot study, we used distance sampling to estimate the pre- and post-hunt sizes of the deer population in Watonwan County. We compared mean distances and deer-group sizes between seasons and within habitats, and also estimated densities of deer using DISTANCE software. To evaluate distance sampling, 24 spotlight surveys were conducted from 18 October-28 December 2004. We observed 537 deer during 12 surveys in the pre-hunt period and 620 deer during 12 surveys in the post-hunt period. Preliminary analyses indicated that mean deer-group sizes differed (P\u3c0.001) between seasons (mean pre-season = 2.1 deer/group [SE = 0.1], mean postseason= 2.9 deer/group [SE = 0.2]). Average distance from deer to observer also differed (P\u3c0.05) between seasons (pre-hunt = 128 m [SE = 5] and post-hunt = 145 m [SE = 7]). Further analysis of our findings will likely demonstrate that distance sampling will improve current techniques and, therefore, estimates of,the size of white-tailed deer populations utilized by the Minnesota Department of Natural Resources

Using Distance Sampling to Estimate Densities of White-Tailed Deer in South-Central Minnesota

Distance sampling is a method of estimating population abundance and density used by wildlife biologists for several species because of its advantages relative to other techniques. However, few wildlife biologists have used distance sampling to estimate abundance of white-tailed deer (Odocoileus virginianus). We describe a distance sampling technique used to estimate prehunt and post-hunt population densities of deer in Watonwan County, Minnesota. Estimates of white-tailed deer density were compared between distance sampling versus population modeling, and costs for distance sampling versus aerial surveys were determined. We drove 2,704 km during 24 spotlight surveys conducted from 21 October to 28 December 2004. We observed 537 white-tailed deer during the pre-hunt period and 620 deer during the post-hunt period. Estimates of white-tailed deer density obtained via distance sampling were more than three times larger than estimates derived by population modeling. Costs for aerial surveys would have been four times greater than costs for distance sampling surveys. We concluded that wildlife biologists should consider implementing distance sampling for estimating deer density because of the advantages and lower costs of distance sampling relative to other techniques