A future food boom rescues the negative effects of early-life adversity on adult lifespan in a small mammal.

Early-life adversity, even when transient, can have lasting effects on individual phenotypes and reduce lifespan across species. If these effects can be mitigated by a high-quality later-life environment, then differences in future resources may explain variable resilience to early-life adversity. Using data from over 1000 wild North American red squirrels, we tested the hypothesis that the costs of early-life adversity for adult lifespan could be offset by later-life food abundance. We identified six adversities that reduced juvenile survival in the first year of life, though only one-birth date-had continued independent effects on adult lifespan. We then built a weighted early-life adversity (wELA) index integrating the sum of adversities and their effect sizes. Greater weighted early-life adversity predicted shorter adult lifespans in males and females, but a naturally occurring food boom in the second year of life ameliorated this effect. Experimental food supplementation did not replicate this pattern, despite increasing lifespan, indicating that the buffering effect of a future food boom may hinge on more than an increase in available calories. Our results suggest a non-deterministic role of early-life conditions for later-life phenotype, highlighting the importance of evaluating the consequences of early-life adversity in the context of an animal's entire life course.

Anthropogenic subsidies influence resource use during a mange epizootic in a desert coyote population.

Colonization of urban areas by synanthropic wildlife introduces novel and complex alterations to established ecological processes, including the emergence and spread of infectious diseases. Aggregation at urban resources can increase disease transfer, with wide-ranging species potentially infecting outlying populations. The garrison at the National Training Center, Fort Irwin, California, USA, was recently colonized by mange-infected coyotes (Canis latrans) that also use the surrounding Mojave Desert. This situation provided an ideal opportunity to examine the effects of urban resources on disease dynamics. We evaluated seasonal space use and determined the influence of anthropogenic subsidies, water sources, and prey density on urban resource selection. We found no difference in home range size between healthy and infected individuals, but infected residents had considerably more spatial overlap with one another than healthy residents. All coyotes selected for anthropogenic subsidies during all seasons, while infected coyotes seasonally selected for urban water sources, and healthy coyotes seasonally selected for urban areas with greater densities of natural prey. These results suggest that while all coyotes were selecting for anthropogenic subsidies, infected resident coyotes demonstrated a greater tolerance for other conspecifics, which could be facilitating the horizontal transfer of sarcoptic mange to non-resident coyotes. Conversely, healthy coyotes also selected for natural prey and healthy residents exhibited a lack of spatial overlap with other coyotes suggesting they were not reliant on anthropogenic subsidies and were maintaining territories. Understanding the association between urban wildlife, zoonotic diseases, and urban resources can be critical in determining effective responses for mitigating future epizootics.

The glucocorticoid response to environmental change is not specific to agents of natural selection in wild red squirrels.

Evolutionary endocrinology aims to understand how natural selection shapes endocrine systems and the degree to which endocrine systems themselves can induce phenotypic responses to environmental changes. Such responses may be specialized in that they reflect past selection for responsiveness only to those ecological factors that ultimately influence natural selection. Alternatively, endocrine responses may be broad and generalized, allowing organisms to cope with a variety of environmental changes simultaneously. Here, we empirically tested whether the endocrine response of female North American red squirrels (Tamiasciurus hudsonicus) was specialized or generalized. We first quantified the direction and magnitude of natural selection acting on three female life history traits (parturition date, litter size, offspring postnatal growth rate) during 32 years of fluctuations in four potential ecological agents of selection (food availability, conspecific density, predator abundance, and temperature). Only three of the four variables (food, density, and predators) affected patterns of natural selection on female life history traits. We then quantified fecal glucocorticoid metabolites (FGMs) across 7 years and found that all four environmental variables, regardless of their effects on patterns of selection, were associated with glucocorticoid production. Our results provide support for a generalized, rather than specific, glucocorticoid response to environmental change that can integrate across multiple co-occurring environmental stressors.

Propagule size and sex ratio influence colonisation dynamics after introduction of a non-native lizard.

The composition of founding populations plays an important role in colonisation dynamics and can influence population growth during early stages of biological invasion. Specifically, founding populations with small propagules (i.e. low number of founders) are vulnerable to the Allee effect and have reduced likelihood of establishment compared to those with large propagules. The founding sex ratio can also impact establishment via its influence on mating success and offspring production. Our goal was to test the effects of propagule size and sex ratio on offspring production and annual population growth following introductions of a non-native lizard species (Anolis sagrei). We manipulated propagule composition on nine small islands, then examined offspring production, population growth and survival rate of founders and their descendants encompassing three generations. By the third reproductive season, per capita offspring production was higher on islands seeded with a relatively large propagule size, but population growth was not associated with propagule size. Propagule sex ratio did not affect offspring production, but populations with a female-biased propagule had positive growth, whereas those with a male-biased propagule had negative growth in the first year. Populations were not affected by propagule sex ratio in subsequent years, possibly due to rapid shifts towards balanced (or slightly female biased) population sex ratios. Overall, we show that different components of population fitness have different responses to propagule size and sex ratio in ways that could affect early stages of biological invasion. Despite these effects, the short life span and high fecundity of A. sagrei likely helped small populations to overcome Allee effects and enabled all populations to successfully establish. Our rare experimental manipulation of propagule size and sex ratio can inform predictions of colonisation dynamics in response to different compositions of founding populations, which is critical in the context of population ecology and invasion dynamics.

Age Predicts Risky Investment Better Than Residual Reproductive Value.

AbstractLife-history theory predicts that investment in reproduction should increase as future reproductive potential (i.e., residual reproductive value [RRV]) decreases. Researchers have thus intuitively used age as a proxy for RRV and assume that RRV decreases with age when interpreting age-specific investment. Yet age is an imperfect proxy for RRV and may even be a poor correlate in some systems. We used a 31-year study of the nesting ecology of painted turtles (Chrysemys picta) to assess how age and RRV compare in explaining variation in a risky investment behavior. We predicted that RRV would be a better predictor of risky investment than age because RRV accounts for variation in future reproductive potential across life. We found that RRV was high in early life, slowly decreased until midlife, and then steadily decreased to terminal reproduction. However, age predicted risky behavior better than RRV. This finding suggests that stronger correlates of age (e.g., size) may be more responsible for this behavior in turtles. This study highlights that researchers should not assume that age-specific investment is driven by RRV and that future work should quantify RRV to more directly test this key element of life-history theory.

Urbanization's influence on the distribution of mange in a carnivore revealed with multistate occupancy models.

Increasing urbanization and use of urban areas by synanthropic wildlife has increased human and domestic animal exposure to zoonotic diseases and exacerbated epizootics within wildlife populations. Consequently, there is a need to improve wildlife disease surveillance programs to rapidly detect outbreaks and refine inferences regarding spatiotemporal disease dynamics. Multistate occupancy models can address potential shortcomings in surveillance programs by accounting for imperfect detection and the misclassification of disease states. We used these models to explore the relationship between urbanization, slope, and the spatial distribution of sarcoptic mange in coyotes (Canis latrans) inhabiting Fort Irwin, California, USA. We deployed remote cameras across 180 sites within the desert surrounding the populated garrison and classified sites by mange presence or absence depending on whether a symptomatic or asymptomatic coyote was photographed. Coyotes selected flatter sites closer to the urban area with a high probability of use (0.845, 95% credible interval (CRI): 0.728, 0.944); site use decreased as the distance to urban areas increased (standardized [Formula: see text] = - 1.354, 95% CRI - 2.423, - 0.619). The probability of correctly classifying mange presence at a site also decreased further from the urban area and was probably related to the severity of mange infection. Severely infected coyotes, which were more readily identified as symptomatic, resided closer to the urban area and were most likely dependent on urban resources for survival; urban resources probably contributed to sustaining the disease. Multistate occupancy models represent a flexible framework for estimating the occurrence and spatial extent of observable infectious diseases, which can improve wildlife disease surveillance programs.

Becoming creatures of habit: Among- and within-individual variation in nesting behaviour shift with age.

The quantification of repeatability has enabled behavioural and evolutionary ecologists to assess the heritable potential of traits. For behavioural traits that vary across life, age-related variation should be accounted for to prevent biasing the microevolutionary estimate of interest. Moreover, to gain a mechanistic understanding of ontogenetic variation in behaviour, among- and within-individual variance should be quantified across life. We leveraged a 30-year study of painted turtles (Chrysemys picta) to assess how age contributes to variation in the repeatability of nesting behaviours. We found that four components of nesting behaviour were repeatable and that accounting for age increased the repeatability estimate for maternal choice of canopy cover over nests. We detected canalization (diminished within-individual variance with age) of canopy cover choice in a reduced data set despite no shift in repeatability. Additionally, random regression analysis revealed that females became more divergent from each other in their choice of canopy cover with age. Thus, properly modelling age-related variance should more precisely estimate heritable potential, and assessing among- and within-individual variance components in addition to repeatability will offer a more mechanistic understanding of behavioural variation across age.

Do Covariances Between Maternal Behavior and Embryonic Physiology Drive Sex-Ratio Evolution Under Environmental Sex Determination?

Fisherian sex-ratio theory predicts sexual species should have a balanced primary sex ratio. However, organisms with environmental sex determination (ESD) are particularly vulnerable to experiencing skewed sex ratios when environmental conditions vary. Theoretical work has modeled sex-ratio dynamics for animals with ESD with regard to 2 traits predicted to be responsive to sex-ratio selection: 1) maternal oviposition behavior and 2) sensitivity of embryonic sex determination to environmental conditions, and much research has since focused on how these traits influence offspring sex ratios. However, relatively few studies have provided estimates of univariate quantitative genetic parameters for these 2 traits, and the existence of phenotypic or genetic covariances among these traits has not been assessed. Here, we leverage studies on 3 species of reptiles (2 turtle species and a lizard) with temperature-dependent sex determination (TSD) to assess phenotypic covariances between measures of maternal oviposition behavior and thermal sensitivity of the sex-determining pathway. These studies quantified maternal behaviors that relate to nest temperature and sex ratio of offspring incubated under controlled conditions. A positive covariance between these traits would enhance the efficiency of sex-ratio selection when primary sex ratio is unbalanced. However, we detected no such covariance between measures of these categories of traits in the 3 study species. These results suggest that maternal oviposition behavior and thermal sensitivity of sex determination in embryos might evolve independently. Such information is critical to understand how animals with TSD will respond to rapidly changing environments that induce sex-ratio selection.

Patterns in artisanal coral reef fisheries revealed through local monitoring efforts.

Sustainable fisheries management is key to restoring and maintaining ecological function and benefits to people, but it requires accurate information about patterns of resource use, particularly fishing pressure. In most coral reef fisheries and other data-poor contexts, obtaining such information is challenging and remains an impediment to effective management. We developed the most comprehensive regional view of shore-based fishing effort and catch published to date, to show detailed fishing patterns from across the main Hawaiian Islands (MHI). We reveal these regional patterns through fisher "creel" surveys conducted by local communities, state agencies, academics, and/or environmental organizations, at 18 sites, comprising >10,000 h of monitoring across a range of habitats and human influences throughout the MHI. All creel surveys included in this study except for one were previously published in some form (peer-reviewed articles or gray literature reports). Here, we synthesize these studies to document spatial patterns in nearshore fisheries catch, effort, catch rates (i.e., catch-per-unit-effort (CPUE)), and catch disposition (i.e., use of fish after catch is landed). This effort provides for a description of general regional patterns based on these location-specific studies. Line fishing was by far the dominant gear type employed. The most efficient gear (i.e., highest CPUE) was spear (0.64 kg h-1), followed closely by net (0.61 kg h-1), with CPUE for line (0.16 kg h-1) substantially lower than the other two methods. Creel surveys also documented illegal fishing activity across the studied locations, although these activities were not consistent across sites. Overall, most of the catch was not sold, but rather retained for home consumption or given away to extended family, which suggests that cultural practices and food security may be stronger drivers of fishing effort than commercial exploitation for coral reef fisheries in Hawai'i. Increased monitoring of spatial patterns in nearshore fisheries can inform targeted management, and can help communities develop a more informed understanding of the drivers of marine resource harvest and the state of the resources, in order to maintain these fisheries for food security, cultural practices, and ecological value.

Interobserver Variability in Histologic Evaluation of Liver Fibrosis Using Categorical and Quantitative Scores.

Objectives: The aim of the study was to investigate the interobserver agreement for categorical and quantitative scores of liver fibrosis. Methods: Sixty-five consecutive biopsy specimens from patients with mixed liver disease etiologies were assessed by three pathologists using the Ishak and nonalcoholic steatohepatitis Clinical Research Network (NASH CRN) scoring systems, and the fibrosis area (collagen proportionate area [CPA]) was estimated by visual inspection (visual-CPA). A subset of 20 biopsy specimens was analyzed using digital imaging analysis (DIA) for the measurement of CPA (DIA-CPA). Results: The bivariate weighted κ between any two pathologists ranged from 0.57 to 0.67 for Ishak staging and from 0.47 to 0.57 for the NASH CRN staging. Bland-Altman analysis showed poor agreement between all possible pathologist pairings for visual-CPA but good agreement between all pathologist pairings for DIA-CPA. There was good agreement between the two pathologists who assessed biopsy specimens by visual-CPA and DIA-CPA. The intraclass correlation coefficient, which is equivalent to the κ statistic for continuous variables, was 0.78 for visual-CPA and 0.97 for DIA-CPA. Conclusions: These results suggest that DIA-CPA is the most robust method for assessing liver fibrosis followed by visual-CPA. Categorical scores perform less well than both the quantitative CPA scores assessed here.

Fat, weather, and date affect migratory songbirds' departure decisions, routes, and time it takes to cross the Gulf of Mexico.

Approximately two thirds of migratory songbirds in eastern North America negotiate the Gulf of Mexico (GOM), where inclement weather coupled with no refueling or resting opportunities can be lethal. However, decisions made when navigating such features and their consequences remain largely unknown due to technological limitations of tracking small animals over large areas. We used automated radio telemetry to track three songbird species (Red-eyed Vireo, Swainson's Thrush, Wood Thrush) from coastal Alabama to the northern Yucatan Peninsula (YP) during fall migration. Detecting songbirds after crossing ∼1,000 km of open water allowed us to examine intrinsic (age, wing length, fat) and extrinsic (weather, date) variables shaping departure decisions, arrival at the YP, and crossing times. Large fat reserves and low humidity, indicative of beneficial synoptic weather patterns, favored southward departure across the Gulf. Individuals detected in the YP departed with large fat reserves and later in the fall with profitable winds, and flight durations (mean = 22.4 h) were positively related to wind profit. Age was not related to departure behavior, arrival, or travel time. However, vireos negotiated the GOM differently than thrushes, including different departure decisions, lower probability of detection in the YP, and longer crossing times. Defense of winter territories by thrushes but not vireos and species-specific foraging habits may explain the divergent migratory behaviors. Fat reserves appear extremely important to departure decisions and arrival in the YP. As habitat along the GOM is degraded, birds may be limited in their ability to acquire fat to cross the Gulf.

Tumour islet Foxp3+ T-cell infiltration predicts poor outcome in nonsmall cell lung cancer.

The impact of host immunity on outcome in nonsmall cell lung cancer (NSCLC) is controversial. We examined the relationship between lymphoid infiltration patterns in NSCLC and prognosis.Tumour- and stroma-infiltrating CD3(+), CD8(+) and forkhead box P3 (Foxp3)(+) T-lymphocytes were identified using immunohistochemistry and a novel image analysis algorithm to assess total, cytotoxic and regulatory T-lymphocyte counts, respectively, in 196 NSCLC cases. The median cell count was selected as a cut-point to define patient subgroups and the ratio of the corresponding tumour islet:stroma (TI/S) counts was determined.There was a positive association between overall survival and increased CD8(+) TI/S ratio (hazard ratio (HR) for death 0.44, p<0.001) but an inverse relationship between Foxp3(+) TI/S ratio and overall survival (HR 4.86, p<0.001). Patients with high CD8(+) islet (HR 0.48, p<0.001) and Foxp3(+) stromal (HR 0.23, p<0.001) counts had better survival, whereas high CD3(+) and CD8(+) stromal counts and high Foxp3(+) islet infiltration conferred a worse survival (HR 1.55, 2.19 and 3.14, respectively). By multivariate analysis, a high CD8(+) TI/S ratio conferred an improved survival (HR 0.48, p=0.002) but a high Foxp3(+) TI/S ratio was associated with worse survival (HR 3.91, p<0.001).Microlocalisation of infiltrating T-lymphocytes is a powerful predictor of outcome in resected NSCLC.

Turbines and Terrestrial Vertebrates: Variation in Tortoise Survivorship Between a Wind Energy Facility and an Adjacent Undisturbed Wildland Area in the Desert Southwest (USA).

With the recent increase in utility-scale wind energy development, researchers have become increasingly concerned how this activity will affect wildlife and their habitat. To understand the potential impacts of wind energy facilities (WEF) post-construction (i.e., operation and maintenance) on wildlife, we compared differences in activity centers and survivorship of Agassiz's desert tortoises (Gopherus agassizii) inside or near a WEF to neighboring tortoises living near a wilderness area (NWA) and farther from the WEF. We found that the size of tortoise activity centers varied, but not significantly so, between the WEF (6.25 ± 2.13 ha) and adjacent NWA (4.13 ± 1.23 ha). However, apparent survival did differ significantly between the habitat types: over the 18-year study period apparent annual survival estimates were 0.96 ± 0.01 for WEF tortoises and 0.92 ± 0.02 for tortoises in the NWA. High annual survival suggests that operation and maintenance of the WEF has not caused considerable declines in the adult population over the past two decades. Low traffic volume, enhanced resource availability, and decreased predator populations may influence annual survivorship at this WEF. Further research on these proximate mechanisms and population recruitment would be useful for mitigating and managing post-development impacts of utility-scale wind energy on long-lived terrestrial vertebrates.

Using motion-sensor camera technology to infer seasonal activity and thermal niche of the desert tortoise (Gopherus agassizii).

Understanding the relationships between environmental variables and wildlife activity is an important part of effective management. The desert tortoise (Gopherus agassizii), an imperiled species of arid environments in the southwest US, may have increasingly restricted windows for activity due to current warming trends. In summer 2013, we deployed 48 motion sensor cameras at the entrances of tortoise burrows to investigate the effects of temperature, sex, and day of the year on the activity of desert tortoises. Using generalized estimating equations, we found that the relative probability of activity was associated with temperature (linear and quadratic), sex, and day of the year. Sex effects showed that male tortoises are generally more active than female tortoises. Temperature had a quadratic effect, indicating that tortoise activity was heightened at a range of temperatures. In addition, we found significant support for interactions between sex and day of the year, and sex and temperature as predictors of the probability of activity. Using our models, we were able to estimate air temperatures and times (days and hours) that were associated with maximum activity during the study. Because tortoise activity is constrained by environmental conditions such as temperature, it is increasingly vital to conduct studies on how tortoises vary their activity throughout the Sonoran Desert to better understand the effects of a changing climate.

Multiparametric magnetic resonance for the non-invasive diagnosis of liver disease.

BACKGROUND & AIMS: With the increasing prevalence of liver disease worldwide, there is an urgent clinical need for reliable methods to diagnose and stage liver pathology. Liver biopsy, the current gold standard, is invasive and limited by sampling and observer dependent variability. In this study, we aimed to assess the diagnostic accuracy of a novel magnetic resonance protocol for liver tissue characterisation. METHODS: We conducted a prospective study comparing our magnetic resonance technique against liver biopsy. The individual components of the scanning protocol were T1 mapping, proton spectroscopy and T2* mapping, which quantified liver fibrosis, steatosis and haemosiderosis, respectively. Unselected adult patients referred for liver biopsy as part of their routine care were recruited. Scans performed prior to liver biopsy were analysed by physicians blinded to the histology results. The associations between magnetic resonance and histology variables were assessed. Receiver-operating characteristic analyses were also carried out. RESULTS: Paired magnetic resonance and biopsy data were obtained in 79 patients. Magnetic resonance measures correlated strongly with histology (r(s)=0.68 p<0.0001 for fibrosis; r(s)=0.89 p<0.001 for steatosis; r(s)=-0.69 p<0.0001 for haemosiderosis). The area under the receiver operating characteristic curve was 0.94, 0.93, and 0.94 for the diagnosis of any degree of fibrosis, steatosis and haemosiderosis respectively. CONCLUSION: The novel scanning method described here provides high diagnostic accuracy for the assessment of liver fibrosis, steatosis and haemosiderosis and could potentially replace liver biopsy for many indications. This is the first demonstration of a non-invasive test to differentiate early stages of fibrosis from normal liver.

MRI characteristics of lipoma and atypical lipomatous tumor/well-differentiated liposarcoma: retrospective comparison with histology and MDM2 gene amplification.

PURPOSE: To review the reliability of MR imaging features for the purpose of distinguishing lipoma and atypical lipomatous tumor/well-differentiated liposarcoma (ALT/WDL). MATERIALS AND METHODS: A retrospective review of 87 patients with histologically proven lipomatous tumors was performed. All underwent MR imaging, assessing lipomatous content, septation, and nodules. The associations between these features and tumor diagnosis based on morphology and the presence or absence of MDM2 amplification were explored. The age of the patient and the size and location of the lesion were also recorded for statistical analysis. RESULTS: Of the 87 patients, 54 were classified as lipomas and 33 as ALT/WDL. MR identified ALT/WDL with a sensitivity of 90.9 % (CI 74.5-97.6) and a specificity of 37.0 % (CI 24.6-51.3). The positive and negative predictive values were 46.9 % (CI 34.5-59.7) and 86.9 % (CI 65.3-96.6), respectively. The mean age of patients with ALT/WDL was greater (60 years [range 40-83 years]) than those with lipoma (52 years [range 10-79 years]) (p = 0.025). The mean size of ALT/WDL (18.7 cm [range 5-36 cm]) was significantly greater than lipoma (13.9 cm [range 3-32 cm]) (p = 0.003). Features that increased the likelihood of ALT/WDL included: patient age over 60 years, maximal lesion dimension over 10 cm, location in lower limb, and presence of non-fatty areas, by a factor of 2.61-6.25 times. CONCLUSIONS: ALT/WDL and lipoma have overlapping MR imaging characteristics. The most reliable imaging discriminators of ALT/WDL were size of lesion and lipomatous content, but due to the overlap in the MRI appearances of lipoma and ALT/WDL, discrimination should be based on molecular pathology rather than imaging.

Sensitivity of MDM2 amplification and unexpected multiple faint alphoid 12 (alpha 12 satellite sequences) signals in atypical lipomatous tumor.

This study assessed whether analysis of MDM2 copy number by fluorescence in situ hybridization (FISH) would help distinguish lipomas from atypical lipomatous tumors, otherwise referred to as well-differentiated liposarcomas, using a commercially available MDM2 FISH kit. 227 lipomatous and 201 non-lipomatous tumors were analyzed to assess its sensitivity and specificity. Of 178 mature lipomatous tumors, 86 were classified histologically as lipoma and 92 as atypical lipomatous tumor. Two of the lipomas harboring MDM2 amplification were reclassified as atypical lipomatous tumors. Overall, 13 atypical lipomatous tumors did not reveal MDM2 or CDK4 amplification, although this was reduced to 12 following analysis of multiple slides. Three of these cases revealed very occasional tumor cells harboring high-level MDM2 amplification, two had a dedifferentiated component, and MDM2 amplification was detected when one tumor recurred. The remaining six cases exhibited reactive/inflammatory features and were reclassified as lipomas. The findings indicate that MDM2 amplification is 93.5% sensitive for diagnosing atypical lipomatous tumor. A total of 2 of the 20 dedifferentiated liposarcomas failed to reveal MDM2 amplification. All atypical lipomatous tumors measured >10 cm, two dedifferentiated liposarcoma presented de novo at <10 cm, and ~50% of lipomas measured >10 cm. Spindle cell lipomas, lipoblastomas, hibernomas and pleomorphic liposarcomas did not reveal MDM2 amplification. Of 201 non-lipomatous tumors, eight revealed MDM2 amplification or multiple faint alphoid 12 signals and were reclassified as dedifferentiated liposarcoma. Multiple faint alphoid 12 signals were observed in nine tumors from seven patients, an observation not previously reported on paraffin sections: these included four atypical lipomatous tumors, and three dedifferentiated liposarcomas, one previously diagnosed as a myxofibrosarcoma, all of which also revealed amplification of CDK4, although two lacked MDM2 amplification. MDM2 FISH test is a useful adjunct to histology for distinguishing lipoma from atypical lipomatous tumor. The limitations of molecular genetic tests must be known before introducing them into a clinical service.

Accuracy of using visual identification of white sharks to estimate residency patterns.

Determining the residency of an aquatic species is important but challenging and it remains unclear what is the best sampling methodology. Photo-identification has been used extensively to estimate patterns of animals' residency and is arguably the most common approach, but it may not be the most effective approach in marine environments. To examine this, in 2005, we deployed acoustic transmitters on 22 white sharks (Carcharodon carcharias) in Mossel Bay, South Africa to quantify the probability of detecting these tagged sharks by photo-identification and different deployment strategies of acoustic telemetry equipment. Using the data collected by the different sampling approaches (detections from an acoustic listening station deployed under a chumming vessel versus those from visual sightings and photo-identification), we quantified the methodologies' probability of detection and determined if the sampling approaches, also including an acoustic telemetry array, produce comparable results for patterns of residency. Photo-identification had the lowest probability of detection and underestimated residency. The underestimation is driven by various factors primarily that acoustic telemetry monitors a large area and this reduces the occurrence of false negatives. Therefore, we propose that researchers need to use acoustic telemetry and also continue to develop new sampling approaches as photo-identification techniques are inadequate to determine residency. Using the methods presented in this paper will allow researchers to further refine sampling approaches that enable them to collect more accurate data that will result in better research and more informed management efforts and policy decisions.

Lymphoepithelioma-like carcinoma of the colon.

An 85-year old female had a polypoid tumour in the sigmoid colon that histologically conformed to a lymphoepithelioma-like (LEL) carcinoma. The tumour was arranged in cords, chains, clusters and microalveoli of pleomorphic, irregular cells set within a dense intratumoral lymphocytic stroma. The tumour was EBV-negative and showed loss of MLH-1 and PMS-2 mismatch repair proteins. The patient did not fulfil the criteria for HNPCC. Only 5 other cases of primary colonic LEL carcinoma have been described previously and only one case appears to have an unequivocal association with EBV. In addition, one of the cases was encountered in a HNPCC patient. This is an unusual morphologic variant of a microsatellite unstable tumour with a LEL pattern, not associated with EBV.