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

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

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

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

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

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

Reduced engagement with social stimuli in 6-month-old infants with later Autism Spectrum Disorder: a longitudinal prospective study of infants at high familial risk

Background: Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder that affects more than 1% of the population, and close to 20% of prospectively studied infants with an older sibling with ASD. Although significant progress has been made in characterizing the emergence of behavioral symptoms of ASD, far less is known about the underlying disruptions to early learning. Recent models suggest that core aspects of the causal path to ASD may only be apparent in early infancy. Here, we investigated social attention in 6- and 12-month-old infants who did and did not meet criteria for ASD at 24 months using both cognitive and electrophysiological methods. We hypothesized that a reduction in attention engagement to faces would be associated with later ASD. Methods: In a prospective longitudinal design, we used measures of both visual attention (habituation) and brain function (event-related potentials to faces and objects) at 6 and 12 months, and investigated the relationship to ASD outcome at 24 months. Results: High-risk infants who met criteria for ASD at 24 months showed shorter epochs of visual attention, faster but less prolonged neural activation to faces, and delayed sensitization responses (increases in looking) to faces at 6 months; these differences were less apparent at 12 months. These findings are consistent with disrupted engagement of sustained attention to social stimuli. Conclusions: These findings suggest that there may be fundamental early disruptions to attention engagement that may have cascading consequences for later social functioning

Recent Shift in Climate Relationship Enables Prediction of the Timing of Bird Breeding

Large-scale climate processes influence many aspects of ecology including breeding phenology, reproductive success and survival across a wide range of taxa. Some effects are direct, for example, in temperate-zone birds, ambient temperature is an important cue enabling breeding effort to coincide with maximum food availability, and earlier breeding in response to warmer springs has been documented in many species. In other cases, time-lags of up to several years in ecological responses have been reported, with effects mediated through biotic mechanisms such as growth rates or abundance of food supplies. Here we use 23 years of data for a temperate woodland bird species, the great tit (Parus major), breeding in deciduous woodland in eastern England to demonstrate a time-lagged linear relationship between the on-set of egg laying and the winter index of the North Atlantic Oscillation such that timing can be predicted from the winter index for the previous year. Thus the timing of bird breeding (and, by inference, the timing of spring events in general) can be predicted one year in advance. We also show that the relationship with the winter index appears to arise through an abiotic time-lag with local spring warmth in our study area. Examining this link between local conditions and larger-scale processes in the longer-term showed that, in the past, significant relationships with the immediately preceding winter index were more common than those with the time-lagged index, and especially so from the late 1930s to the early 1970s. However, from the mid 1970s onwards, the time-lagged relationship has become the most significant, suggesting a recent change in climate patterns. The strength of the current time-lagged relationship suggests that it might have relevance for other temperature-dependent ecological relationships

Face scanning and spontaneous emotion preference in Cornelia de Lange syndrome and Rubinstein-Taybi syndrome

Background Existing literature suggests differences in face scanning in individuals with different socio-behavioural characteristics. Cornelia de Lange syndrome (CdLS) and Rubinstein-Taybi syndrome (RTS) are two genetically defined neurodevelopmental disorders with unique profiles of social behaviour. Methods Here, we examine eye gaze to the eye and mouth regions of neutrally expressive faces, as well as the spontaneous visual preference for happy and disgusted facial expressions compared to neutral faces, in individuals with CdLS versus RTS. Results Results indicate that the amount of time spent looking at the eye and mouth regions of faces was similar in 15 individuals with CdLS and 17 individuals with RTS. Both participant groups also showed a similar pattern of spontaneous visual preference for emotions. Conclusions These results provide insight into two rare, genetically defined neurodevelopmental disorders that have been reported to exhibit contrasting socio-behavioural characteristics and suggest that differences in social behaviour may not be sufficient to predict attention to the eye region of faces. These results also suggest that differences in the social behaviours of these two groups may be cognitively mediated rather than subcortically mediated