Aspects of Key Largo woodrat ecology

Development on the island of Key Largo, Florida, has isolated the Key Largo woodrat (KLWR, Neotoma floridana smalli) on approximately 850 ha of remaining habitat. The KLWR was listed as a federally endangered species in 1984, yet there is still only a limited amount of knowledge about its ecology and population dynamics. The objective of this study was to produce reliable information on KLWR ecology to aid in its management and recovery. Specifically, the study examined (1) the trend and status of the KLWR population, (2) KLWR habitat and nesting preferences, (3) the potential of a fatal disease on KLWR, (4) the movements and ranges of the KLWR, and (5) the viability of the KLWR population. I trapped on 60 (1-ha) grids from March to September 2002 and 10 (1-ha) grids in October 2002 and January, April, and July 2003. Additionally I radio-collared 17 KLWRs and tracked them from March to November 2002. I estimated the current population of KLWR to be between 26 and 106 individuals. I found KLWR selected young hammock (disturbed > 1971) over medium (disturbed between 1940-1971) and old hammock (disturbed 1971) habitat and the creation of nesting habitat for the KLWR within these areas. I would also advocate a large-scale captive breeding and augmentation of the population along with continued research on the limiting factors that are driving the KLWR toward extinction

Domestic cats and dogs create a landscape of fear for pest rodents around rural homesteads

Using domestic predators such as cats to control rodent pest problems around farms and homesteads is common across the world. However, practical scientific evidence on the impact of such biological control in agricultural settings is often lacking. We tested whether the presence of domestic cats and/or dogs in rural homesteads would affect the foraging behaviour of pest rodents. We estimated giving up densities (GUDs) from established feeding patches and estimated relative rodent activity using tracking tiles at 40 homesteads across four agricultural communities. We found that the presence of cats and dogs at the same homestead significantly reduced activity and increased GUDs (i.e. increased perception of foraging cost) of pest rodent species. However, if only cats or dogs alone were present at the homestead there was no observed difference in rodent foraging activity in comparison to homesteads with no cats or dogs. Our results suggest that pest rodent activity can be discouraged through the presence of domestic predators. When different types of predator are present together they likely create a heightened landscape of fear for foraging rodents

Aspects of Key Largo woodrat ecology

Development on the island of Key Largo, Florida, has isolated the Key Largo woodrat (KLWR, Neotoma floridana smalli) on approximately 850 ha of remaining habitat. The KLWR was listed as a federally endangered species in 1984, yet there is still only a limited amount of knowledge about its ecology and population dynamics. The objective of this study was to produce reliable information on KLWR ecology to aid in its management and recovery. Specifically, the study examined (1) the trend and status of the KLWR population, (2) KLWR habitat and nesting preferences, (3) the potential of a fatal disease on KLWR, (4) the movements and ranges of the KLWR, and (5) the viability of the KLWR population. I trapped on 60 (1-ha) grids from March to September 2002 and 10 (1-ha) grids in October 2002 and January, April, and July 2003. Additionally I radio-collared 17 KLWRs and tracked them from March to November 2002. I estimated the current population of KLWR to be between 26 and 106 individuals. I found KLWR selected young hammock (disturbed > 1971) over medium (disturbed between 1940-1971) and old hammock (disturbed 1971) habitat and the creation of nesting habitat for the KLWR within these areas. I would also advocate a large-scale captive breeding and augmentation of the population along with continued research on the limiting factors that are driving the KLWR toward extinction

You Are What You Ate: Using Bioarchaeology to Promote Healthy Eating

YesThe You Are What You Ate project is a collaboration between historians, archaeologists, museum officers, medieval re-enactors and food scientists. We aim to encourage public debate and personal reflection on modern eating habits through exploration of the dietary choices of the medieval and early modern period. This paper will discuss our osteology workshops, aimed at adults or at school children. We use archaeological examples of diet-related conditions, including dental disease, scurvy, rickets and gout, plus those associated with obesity such as osteoarthritis and DISH, to help the public visualise how dietary choices can affect the body. This information is delivered via an introductory talk and carefully monitored bone handling sessions – and, for the children, includes the analysis of a plastic skeleton modified to display pathological conditions. Evaluation data shows that the majority of adults and all children feel they have learnt something new during the sessions, and that this has led them to think about healthy eating. The inclusion of examples of dental pathology has promoted dental hygiene to school children, although it was not one of our primary aims. It is difficult to assess if these short-term experiences translate to long-term knowledge gain or to changes in behaviour

Resuscitation and quantification of stressed Escherichia coli K12 NCTC8797 in water samples

The aim of this study was to investigate the impact on numbers of using different media for the enumeration of Escherichia coli subjected to stress, and to evaluate the use of different resuscitation methods on bacterial numbers. E. coli was subjected to heat stress by exposure to 55 °C for 1 h or to light-induced oxidative stress by exposure to artificial light for up to 8 h in the presence of methylene blue. In both cases, the bacterial counts on selective media were below the limits of detection whereas on non-selective media colonies were still produced. After resuscitation in non-selective media, using a multi-well MPN resuscitation method or resuscitation on membrane filters, the bacterial counts on selective media matched those on non-selective media. Heat and light stress can affect the ability of E. coli to grow on selective media essential for the enumeration as indicator bacteria. A resuscitation method is essential for the recovery of these stressed bacteria in order to avoid underestimation of indicator bacteria numbers in water. There was no difference in resuscitation efficiency using the membrane filter and multi-well MPN methods. This study emphasises the need to use a resuscitation method if the numbers of indicator bacteria in water samples are not to be underestimated. False-negative results in the analysis of drinking water or natural bathing waters could have profound health effects

Demographic profiles and environmental drivers of variation relate to individual breeding state in a long-lived trans-oceanic migratory seabird, the Manx shearwater

Understanding the points in a species breeding cycle when they are most vulnerable to environmental fluctuations is key to understanding interannual demography and guiding effective conservation and management. Seabirds represent one of the most threatened groups of birds in the world, and climate change and severe weather is a prominent and increasing threat to this group. We used a multi-state capture-recapture model to examine how the demographic rates of a long-lived trans-oceanic migrant seabird, the Manx shearwater Puffinus puffinus, are influenced by environmental conditions experienced at different stages of the annual breeding cycle and whether these relationships vary with an individual's breeding state in the previous year (i.e., successful breeder, failed breeder and non-breeder). Our results imply that populations of Manx shearwaters are comprised of individuals with different demographic profiles, whereby more successful reproduction is associated with higher rates of survival and breeding propensity. However, we found that all birds experienced the same negative relationship between rates of survival and wind force during the breeding season, indicating a cost of reproduction (or central place constraint for non-breeders) during years with severe weather conditions. We also found that environmental effects differentially influence the breeding propensity of individuals in different breeding states. This suggests individual spatio-temporal variation in habitat use during the annual cycle, such that climate change could alter the frequency that individuals with different demographic profiles breed thereby driving a complex and less predictable population response. More broadly, our study highlights the importance of considering individual-level factors when examining population demography and predicting how species may respond to climate change

Integrating evolution into ecological modelling: accommodating phenotypic changes in agent based models.

PMCID: PMC3733718This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Evolutionary change is a characteristic of living organisms and forms one of the ways in which species adapt to changed conditions. However, most ecological models do not incorporate this ubiquitous phenomenon. We have developed a model that takes a 'phenotypic gambit' approach and focuses on changes in the frequency of phenotypes (which differ in timing of breeding and fecundity) within a population, using, as an example, seasonal breeding. Fitness per phenotype calculated as the individual's contribution to population growth on an annual basis coincide with the population dynamics per phenotype. Simplified model variants were explored to examine whether the complexity included in the model is justified. Outputs from the spatially implicit model underestimated the number of individuals across all phenotypes. When no phenotype transitions are included (i.e. offspring always inherit their parent's phenotype) numbers of all individuals are always underestimated. We conclude that by using a phenotypic gambit approach evolutionary dynamics can be incorporated into individual based models, and that all that is required is an understanding of the probability of offspring inheriting the parental phenotype

Functional near infrared spectroscopy (fNIRS) to assess cognitive function in infants in rural Africa

Cortical mapping of cognitive function during infancy is poorly understood in low-income countries due to the lack of transportable neuroimaging methods. We have successfully piloted functional near infrared spectroscopy (fNIRS) as a neuroimaging tool in rural Gambia. Four-to-eight month old infants watched videos of Gambian adults perform social movements, while haemodynamic responses were recorded using fNIRS. We found distinct regions of the posterior superior temporal and inferior frontal cortex that evidenced either visual-social activation or vocally selective activation (vocal > non-vocal). The patterns of selective cortical activation in Gambian infants replicated those observed within similar aged infants in the UK. These are the first reported data on the measurement of localized functional brain activity in young infants in Africa and demonstrate the potential that fNIRS offers for field-based neuroimaging research of cognitive function in resource-poor rural communities

Interneuronal mechanism for Tinbergen's hierarchical model of behavioral choice

Recent studies of behavioral choice support the notion that the decision to carry out one behavior rather than another depends on the reconfiguration of shared interneuronal networks. We investigated another decision-making strategy, derived from the classical ethological literature, which proposes that behavioral choice depends on competition between autonomous networks. According to this model, behavioral choice depends on inhibitory interactions between incompatible hierarchically organized behaviors. We provide evidence for this by investigating the interneuronal mechanisms mediating behavioral choice between two autonomous circuits that underlie whole-body withdrawal and feeding in the pond snail Lymnaea. Whole-body withdrawal is a defensive reflex that is initiated by tactile contact with predators. As predicted by the hierarchical model, tactile stimuli that evoke whole-body withdrawal responses also inhibit ongoing feeding in the presence of feeding stimuli. By recording neurons from the feeding and withdrawal networks, we found no direct synaptic connections between the interneuronal and motoneuronal elements that generate the two behaviors. Instead, we discovered that behavioral choice depends on the interaction between two unique types of interneurons with asymmetrical synaptic connectivity that allows withdrawal to override feeding. One type of interneuron, the Pleuro-Buccal (PlB), is an extrinsic modulatory neuron of the feeding network that completely inhibits feeding when excited by touch-induced monosynaptic input from the second type of interneuron, Pedal-Dorsal12 (PeD12). PeD12 plays a critical role in behavioral choice by providing a synaptic pathway joining the two behavioral networks that underlies the competitive dominance of whole-body withdrawal over feeding

Functional near infrared spectroscopy (fNIRS) to assess cognitive function in infants in rural Africa

Cortical mapping of cognitive function during infancy is poorly understood in low-income countries due to the lack of transportable neuroimaging methods. We have successfully piloted functional near infrared spectroscopy (fNIRS) as a neuroimaging tool in rural Gambia. Four-to-eight month old infants watched videos of Gambian adults perform social movements, while haemodynamic responses were recorded using fNIRS. We found distinct regions of the posterior superior temporal and inferior frontal cortex that evidenced either visual-social activation or vocally selective activation (vocal > non-vocal). The patterns of selective cortical activation in Gambian infants replicated those observed within similar aged infants in the UK. These are the first reported data on the measurement of localized functional brain activity in young infants in Africa and demonstrate the potential that fNIRS offers for field-based neuroimaging research of cognitive function in resource-poor rural communities