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The author discusses the effort to improve understanding of forest birds and how management activities may be affecting breeding success and populations. He cites a research project by Dan Welsh on forest songbirds to study the long-term effects of forest management on breeding songbirds. According to the author, forest birds are widely investigated because they are good subjects for investigation and results are often directly applicable to forest or other resource management. Funding agencies that supported projects across Canada are mentioned.

Editorial. Focuses on the old growth forest policy of Canada. Decline of forests; Rate of deforestation; Public perception of forest management in Canada.

The probability of prey encounter, attack, capture, and kill are often hypothesized to depend on habitat structure, but field evidence in terrestrial systems is rare. We tested whether predation efficiency by the American marten (Manes americana) and fear of predation by their primary prey, the red-backed vole (Clethrioiwmys gapperi), differed between 20- to 50-year-old regenerating forest stands and older uncut stands. Our results showed that the frequency of prey encounter, prey attack, and prey kill were higher in old uncut forests, despite the fact that small-mammal density was similar to that in younger logged forests. These differences in predation efficiency were linked to higher abundance of coarse woody debris, which seems to offer sensory cues to martens, thereby increasing the odds of hunting success. Red-backed voles in regenerating forest stands exhibited increased wariness compared to voles living in old uncut forest, suggestive of a behavioral response to habitat-mediated variation in predation risk. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate the osteoconductivity of bovine bone mineral in humans. Fifteen patients referred to a private specialist surgical practice were treated consecutively for the repair of alveolar defects, and/or ridge maintenance at the site of extraction sockets, prior to implantation. Bio-Oss xenograft (Geistlich Pharma, Wolhusen, Switzerland) was utilized as the principal grafting material. Bone cores were trephined out at the time of implant placement and processed and examined to evaluate the tissue response under the light microscope. A total of 22 trephines were processed for histomorphometric evaluation to calculate the mean percentage of bone, residual graft and connective tissue by area. In addition, the mean percentage bone-to-graft contact was also calculated. The mean percentage area of new bone formation was 26.9%, and the percentage of residual graft and connective tissue as 25.6% and 47.4% respectively. The mean percentage contact length between bone and residual graft was 34%. One implant placed into a site, which was histologically identified as having little new bone and, unusually, an inflammatory infiltrate, failed with mobility at abutment connection. All other implants were restored into function, with a survival rate at baseline of 97%. To cite this article: Norton MR, Odell EW, Thompson ID, Cook RJ. Efficacy of bovine bone mineral for alveolar augmentation: a human histologic study. Clin. Oral Impl. Res. 14, 2003, 775–783 [ABSTRACT FROM AUTHOR]

Adult female survival and calf recruitment influence population dynamics, but there is limited information on calving and neonatal mortality of boreal woodland caribou (Rangifer tarandus caribou; caribou) in Ontario, Canada. We identified calf parturition sites and 5‐week neonatal mortality using a movement‐based approach across 3 northern Ontario study regions (Pickle Lake, Nakina, and Cochrane) that vary in their capacity to support caribou populations. In comparing 22 caribou‐years of video‐collar footage during 2010–2013 to predictions of the movement‐based approach, we found live parturition events were 100% correctly classified, date of parturition was within 1.08 ± 0.28 (x¯ ± SE) days, and mortality events up to 5 weeks postpartum were 88% correctly classified. Across study regions, 87% of 186 caribou were pregnant and 76% of 107 caribou‐years indicated birth events with median parturition dates a week later in Cochrane (23 May) than in Pickle Lake (17 May) and Nakina (16 May). Based on selection ratios of caribou‐years with calves‐at‐heel (n = 80), caribou consistently selected for lowlands and closed‐canopied forests and mostly against early‐seral stands (<20 yrs old) and areas near linear features during the neonatal and the post‐neonatal period (up to 35 days postpartum). Based on the video footage and movement models, 30% of 81 caribou‐years that indicated live births also showed females lost their calf within the first 5 weeks postpartum, with higher risk of neonatal mortality associated with increased use of lowlands and greater postpartum movement rates. This study provides informative metrics of caribou reproduction across northern Ontario that will contribute to future population modeling and identifies important landscape features to be considered in future industrial development and land use planning for caribou conservation. © 2020 The Wildlife Society. Parturition and neonatal mortality rates can be predicted accurately from movement rates. Caribou selected calving (neonatal and post‐neonatal) areas to minimize predation risk, but greater use of lowlands and increased movement rates postpartum increased risk of neonatal mortality. [ABSTRACT FROM AUTHOR]

One of the most challenging tasks in wildlife conservation and management is to clarify how spatial variation in land cover due to anthropogenic disturbance influences wildlife demography and long‐term viability. To evaluate this, we compared rates of survival and population growth by woodland caribou (Rangifer tarandus caribou) from 2 study sites in northern Ontario, Canada that differed in the degree of anthropogenic disturbance because of commercial logging and road development, resulting in differences in predation risk due to gray wolves (Canis lupus). We used an individual‐based model for population viability analysis (PVA) that incorporated adaptive patterns of caribou movement in relation to predation risk and food availability to predict stochastic variation in rates of caribou survival. Field estimates of annual survival rates for adult female caribou in the unlogged (x¯= 0.90) and logged (x¯= 0.76) study sites recorded during 2010–2014 did not differ significantly (P > 0.05) from values predicted by the individual‐based PVA model (unlogged: x¯ = 0.87; logged: x¯= 0.79). Outcomes from the individual‐based PVA model and a simpler stage‐structured matrix model suggest that substantial differences in adult survival largely due to wolf predation are likely to lead to long‐term decline of woodland caribou in the commercially logged landscape, whereas the unlogged landscape should be considerably more capable of sustaining caribou. Estimates of population growth rates (λ) for the 2010–2014 period differed little between the matrix model and the individual‐based PVA model for the unlogged (matrix model x¯ = 1.01; individual‐based model x¯ = 0.98) and logged landscape (matrix model x¯ = 0.88; individual‐based model x¯ = 0.89). We applied the spatially explicit PVA model to assess the viability of woodland caribou across 14 woodland caribou ranges in Ontario. Outcomes of these simulations suggest that woodland caribou ranges that have experienced significant levels of commercial forestry activities in the past had annual growth rates <0.89, whereas caribou ranges that had not experienced commercial forestry operations had population growth rates >0.96. These differences were strongly related to regional variation in wolf densities. Our results suggest that increased wolf predation risk due to anthropogenic disturbance is of sufficient magnitude to cause appreciable risk of population decline in woodland caribou in Ontario. © 2020 The Authors. The Journal of Wildlife Management published by Wiley Periodicals, Inc. on behalf of The Wildlife Society. We used matrix and individual‐based population viability assessment models to compare the demography of woodland caribou populations in Ontario in unlogged landscapes with those in logged landscapes. Our results suggest that increased wolf predation risk due to anthropogenic disturbance is of sufficient magnitude to cause appreciable risk of population decline in woodland caribou in Ontario. [ABSTRACT FROM AUTHOR]

ABSTRACT: Habitat loss has been implicated in the decline of forest‐dwelling caribou (Rangifer tarandus caribou), but it is unknown how biting insects, potentially important components of boreal forest habitat for caribou, influence the activity of this threatened species. During summers in 2011 and 2012 in northern Ontario, Canada, we quantified the relative abundance of black flies, mosquitoes, and tabanids in boreal forest stands of different ages and related their abundance to caribou activity. We counted insects in young (25–35 yrs since forest harvesting), intermediate (36–69 yrs), and old (≥70 yrs) stands using sweep nets and counts on human subjects. We related the daily variation in abundance of these insect families, along with daily maximum temperature, to the activity of female caribou, determined by accelerometers in global positioning system collars. We found higher insect abundance in young versus old stands. During the first 5 minutes in a forest stand, the rate of accumulation of mosquitoes and black flies on human subjects increased, but at a decelerating rate, whereas tabanid abundance declined over time. On days when tabanids were more numerous, female caribou were less active, possibly a response to reduce exposure and harassment. To a lesser extent, mosquitoes and black flies also tended to elicit lower activity of caribou. Our study reveals that biting flies can alter the behavior of female caribou in the boreal forest. Loss of old stands may accentuate the potential for insect harassment. © 2018 The Wildlife Society. [ABSTRACT FROM AUTHOR]

Although local variation in territorial predator density is often correlated with habitat quality, the causal mechanism underlying this frequently observed association is poorly understood and could stem from facultative adjustment in either group size or territory size., To test between these alternative hypotheses, we used a novel statistical framework to construct a winter population-level utilization distribution for wolves ( Canis lupus) in northern Ontario, which we then linked to a suite of environmental variables to determine factors influencing wolf space use. Next, we compared habitat quality metrics emerging from this analysis as well as an independent measure of prey abundance, with pack size and territory size to investigate which hypothesis was most supported by the data., We show that wolf space use patterns were concentrated near deciduous, mixed deciduous/coniferous and disturbed forest stands favoured by moose ( Alces alces), the predominant prey species in the diet of wolves in northern Ontario, and in proximity to linear corridors, including shorelines and road networks remaining from commercial forestry activities., We then demonstrate that landscape metrics of wolf habitat quality - projected wolf use, probability of moose occupancy and proportion of preferred land cover classes - were inversely related to territory size but unrelated to pack size., These results suggest that wolves in boreal ecosystems alter territory size, but not pack size, in response to local variation in habitat quality. This could be an adaptive strategy to balance trade-offs between territorial defence costs and energetic gains due to resource acquisition. That pack size was not responsive to habitat quality suggests that variation in group size is influenced by other factors such as intraspecific competition between wolf packs. [ABSTRACT FROM AUTHOR]

Primary cortical areas normally have a single mapping of the receptor array arising from a ‘point-to-point’ projection from the thalamus. We show that, for the visual cortex, this simple mapping rule breaks down when retinal input to the thalamus is altered. We utilize the monocular enucleation paradigm, which alters subcortical mappings ipsilateral to the remaining eye. We show that this manipulation produces an altered visuotopic map in area 17 with two separated, mirror-imaged representations of the central visual field. Furthermore, thalamic point-to-point connectivity is dramatically changed. There are now two overlapping geniculocortical projections: the predominant projection maps with apparently normal topography, and a second projection maps with the opposite polarity. The plane of symmetry of the duplicated anatomical projection coincides precisely with the functional map reversal and, notably, geniculocortical magnification factors are identical in the two projections. We suggest that the duplicated, abnormal geniculocortical projection is retinotopically matched to the normal projection. We speculate that aberrant geniculocortical terminals are stabilized because they have coherent activity patterns with topographically normal terminals. [ABSTRACT FROM AUTHOR]

To understand bat biology and appreciate their dependence on and role within forested ecosystems, the biological resolution at which studies are directed must elucidate species and gender patterns. We studied species- and gender-specific aspects of summer range extent and stand selection in northern long-eared bats (Myotis septentrionalis) and little brown bats (M. lucifugus) in the Greater Fundy Ecosystem, New Brunswick, Canada, using trapping, radiotelemetry, and ultrasonic monitoring. Our results suggested that this 2-species system is comprised of 4 ecologically distinct groups with respect to site selection and range extent for roosting and foraging. All bats exhibited an affinity to specific roosting areas. Myotis septentrionalis roosted and foraged in the forest interior. The roosting and foraging areas for females were 6.1 times and 3.4 times larger, respectively, than for males. Both genders foraged in site types in proportion to their availability. Myotis lucifugus females roosted in buildings outside the cote study area, and those captured in the forested landscape were transients. Compared to male and female M. septentrionalis, male M. lucifugus had intermediate-sized roosting areas but the largest foraging areas. Water sites were selected during foraging more than expected. Bat foraging activity, measured acoustically at 8 site types, was greatest at lakes and least above the forest canopy. Male M. lucifugus activity levels were positively associated with temperature and the amount of mature coniferous forest and water within 1 km of the sampling site, and they were negatively associated with the amount of mature deciduous forest within 1 km of the site. Our results suggested that understanding gender effects is crucial for accurate characterization of forest bat habitats. Studies of bats that combine data for genders, species, or guilds may produce spurious results and may be of minimal value for, or actually hinder, bat conservation and management programs. [ABSTRACT FROM AUTHOR]

Summary: During development of the retinocollicular projection in mouse, retinal axons initially overshoot their future termination zones (TZs) in the superior colliculus (SC). The formation of TZs is initiated by interstitial branching at topographically appropriate positions. Ephrin-As are expressed in a decreasing posterior-to-anterior gradient in the SC, and they suppress branching posterior to future TZs. Here we investigate the role of an EphA7 gradient in the SC, which has the reverse orientation to the ephrin-A gradient. We find that in EphA7 mutant mice the retinocollicular map is disrupted, with nasal and temporal axons forming additional or extended TZs, respectively. In vitro, retinal axons are repelled from growing on EphA7-containing stripes. Our data support the idea that EphA7 is involved in suppressing branching anterior to future TZs. These findings suggest that opposing ephrin-A and EphA gradients are required for the proper development of the retinocollicular projection. [Copyright &y& Elsevier]

Lesion studies suggest that primary auditory cortex (A1) is required for accurate sound localization by carnivores and primates. In order to elucidate further its role in spatial hearing, we examined the behavioural consequences of reversibly inactivating ferret A1 over long periods, using Elvax implants releasing the GABAA receptor agonist muscimol. Sub-dural polymer placements were shown to deliver relatively constant levels of muscimol to underlying cortex for >5 months. The measured diffusion of muscimol beneath and around the implant was limited to 1 mm. Cortical silencing was assessed electrophysiologically in both auditory and visual cortices. This exhibited rapid onset and was reversed within a few hours of implant removal. Inactivation of cortical neurons extended to all layers for implants lasting up to 6 weeks and throughout at least layers I–IV for longer placements, whereas thalamic activity in layer IV appeared to be unaffected. Blockade of cortical neurons in the deeper layers was restricted to ≤ 500 µm from the edge of the implant, but was usually more widespread in the superficial layers. In contrast, drug-free Elvax implants had little discernible effect on the responses of the underlying cortical neurons. Bilateral implants of muscimol–Elvax over A1 produced significant deficits in the localization of brief sounds in horizontal space and particularly a reduced ability to discriminate between anterior and posterior sound sources. The performance of these ferrets gradually improved over the period in which the Elvax was in place and attained that of control animals following its removal. Although similar in nature, these deficits were less pronounced than those caused by cortical lesions and suggest a specific role for A1 in resolving the spatial ambiguities inherent in auditory localization cues. [ABSTRACT FROM AUTHOR]

Objective: To describe student use and perceptions of online simulated prescription analysis following integration of supplemental and replacement models into pharmacy practice teaching., Methods: Strathclyde Computerized Randomized Interactive Prescription Tutor (SCRIPT) is a simulated prescription analysis tool designed to support a pharmacy practice competency class. In 2008-2009, SCRIPT scenarios were released to coincide with timetabled teaching as the supplemental model. In 2009-2010, SCRIPT also replaced one-sixth of the taught component of the class as the replacement model. Student use and performance were compared, and their perceptions were documented., Results: In both cohorts, the majority of use (over 70%) occurred immediately before assessments. Remote access decreased from 6409 (supplemental) to 3782 (replacement) attempts per 100 students. There was no difference in student performance between the cohorts, Students reported group and individual use and 4 targeted approaches using SCRIPT., Conclusion: E-learning can reduce the staff time in pharmacy practice teaching without affecting student performance. SCRIPT permits flexible learning that suits student preferences.

Lichens are an important component of the boreal forest, where they are long lived, tend to accumulate in older stands, and are a major food source for the threatened woodland caribou (Rangifer tarandus caribou). To be fully sustainable, silvicultural practices in the boreal forest must include the conservation of ecological integrity. Dominant forest management practices, however, have short-term negative effects on lichen diversity, particularly the application of herbicides. To better understand the long-term effects of forest management, we examined lichen regeneration in 35 mixed black spruce (Picea mariana) and jack pine (Pinus banksiana) forest stands across northern Ontario to determine recovery following logging and postharvest silvicultural practices. Our forest stands were 25-40 years old and had undergone 3 common sivilcultural treatments that included harvested and planted; harvested, planted, and treated with N-[phosphonomethyl] glycine (glyphosate); and harvested, planted, and treated with 2,4-dichlorophenoxyacetic acid (2,4-D). Forest stands with herbicide treatments had lower lichen biomass and higher beta and gamma diversity than planted stands that were not treated chemically or control stands. In northwestern Ontario, planted stands that were not treated chemically had significantly greater (p < 0.05) alpha diversity than stands treated with herbicides or control stands. Our results show that common silvicultural practices do not emulate natural disturbances caused by wildfires in the boreal forest for the lichen community. We suggest a reduction in the amount of chemical application be considered in areas where lichen biomass is likely to be high and where the recovery of woodland caribou is an objective., (© 2013 Society for Conservation Biology.)

Unnecessary over-preparation of carious enamel often occurs clinically during operative caries management. The working hypothesis to be investigated in this study is the potential for bio-active glass air abrasion to remove selectively only demineralised enamel in artificial enamel lesions when compared to equivalent alumina air abrasion, so potentially minimising cavity over-preparation. Bisected artificial, paired smooth surface enamel lesions on ethics-approved, extracted sound human molars were created and subsequently air abraded with 27 μm alumina (n = 19) and bio-active glass (n = 19). The difference between pre-operative lesion boundary and post-operative cavity margin was calculated following optical confocal fluorescent assessment of the lesion boundary. Data indicated mean% over-preparation (sound enamel removal) of 176% with alumina and 15.2% for bio-active glass (p = 0.005). Bio-active glass abrasion removed completely the demineralised enamel from artificial lesions with clinically insignificant over-preparation of sound tissue, indicating technique selectivity towards grossly demineralised enamel. Alumina air abrasion resulted in substantial enamel removal in both sound and demineralised tissues indicating the operator selectivity required to use the techniques effectively in clinical practice.

The assumption that mortality risk increases with dispersal distance has rarely been tested. We compared patterns of natal dispersal in the American marten (Martes americana) between a large regenerating forest landscape and an uncut landscape that was dominated by more mature forest to test whether mortality risk increased with dispersal distance, and whether variation in mortality risk influenced dispersal distance. Mortality risk increased with dispersal distance in both landscape treatments, but the distance-dependent increase in mortality in the regenerating landscape was twice that in the uncut landscape. Differences in body condition, supported by other data on foraging efficiency, suggested that juveniles from the regenerating landscape were less able to cope with the energetic demands of dispersal compared with juveniles from older forests. Juveniles travelled shorter distances in the regenerating versus uncut landscape. These results implied that dispersal was costly in terms of juvenile survival and that mean dispersal distance was shaped, in part, by mortality risk.

A growing number of surface treated titanium implants are routinely used in dental and orthopaedic surgery, with a view to enhancing integration capacity with osseous tissue. This study examines the use of bioactive glass 45S5 as an alternative abrasive and osteoproductive surface modification material. Abrasive blasting of commercially pure titanium with bioactive glass 45S5 produced an irregular finish with a surface roughness average (S(a)) of 1.1 microm as determined by white light interferometry, backscattered and secondary electron microscopy. The roughness attained compares favourably with currently used implant designs. Further, Energy Dispersive X-ray Analysis (EDXA) and backscattered electron microscopy demonstrated that bioactive glass was distributed across the titanium surface and retained within fissures and roughened surface features. Being an osteoproductive material, this is advantageous as it is expected that the modified metallic surfaces will acquire osteopromotive properties, and thus be of benefit to the process of implantation in osseous tissue.

The general principles of scale and coarse and fine filters have been widely accepted, but management agencies and industry are still grappling with the question of what to monitor to detect changes in forest biodiversity following forest management. Part of this problem can be attributed to the lack of focused questions for monitoring including absence of null models and predicted effects, a certain level of disconnect between research and management, and recognition that monitoring can be designed as a research question. Considerable research from the past decade has not been adequately synthesized to answer important questions, such as which species or forest attributes might be the best indicators of change. A disproportionate research emphasis has been placed on community ecology, and mostly on a few groups of organisms including arthropods, amphibians, migratory songbirds, and small mammals, while other species, including soil organisms, lichens, bats, raptors, some carnivores, and larger mammals remain less well-known. In most studies of community ecology, the question of what is the importance, if any, of the regularly observed subtle changes in community structures, and causes of observed changes is usually not answered. Hence, our ability to deal with questions of persistence is limited, and demographic research on regionally-defined key species (such as species linked to processes, species whose persistence may be affected, species with large home ranges, species already selected as indicators, and rare and threatened species) is urgently needed. Monitoring programs need to be designed to enable managers to respond to unexpected changes caused by forest management. To do this, management agencies need to articulate null models for monitoring that predict effects, focus fine-scale monitoring on key species (defined by local and regional research) in key habitats (rare, declining, important) across landscapes, and have a protocol in place to adapt management strategies to changes observed. Finally, agencies must have some way to determine and define when a significant change has occurred and to predict the persistence of species; this too should flow from a well-designed null model.

Neurons in the deeper layers of the superior colliculus (SC) have spatially tuned receptive fields that are arranged to form a map of auditory space. The spatial tuning of these neurons emerges gradually in an experience-dependent manner after the onset of hearing, but the relative contributions of peripheral and central factors in this process of maturation are unknown. We have studied the postnatal development of the projection to the ferret SC from the nucleus of the brachium of the inferior colliculus (nBIC), its main source of auditory input, to determine whether the emergence of auditory map topography can be attributed to anatomical rewiring of this projection. The pattern of retrograde labeling produced by injections of fluorescent microspheres in the SC on postnatal day (P) 0 and just after the age of hearing onset (P29), showed that the nBIC-SC projection is topographically organized in the rostrocaudal axis, along which sound azimuth is represented, from birth. Injections of biotinylated dextran amine-fluorescein into the nBIC at different ages (P30, 60, and 90) labeled axons with numerous terminals and en passant boutons throughout the deeper layers of the SC. This labeling covered the entire mediolateral extent of the SC, but, in keeping with the pattern of retrograde labeling following microsphere injections in the SC, was more restricted rostrocaudally. No systematic changes were observed with age. The stability of the nBIC-SC projection over this period suggests that developmental changes in auditory spatial tuning involve other processes, rather than a gross refinement of the projection from the nBIC., (Copyright 2005 Wiley-Liss, Inc.)

The cytoarchitectonically-uniform dorsal lateral geniculate nucleus (dLGN) can be biochemically and anatomically subdivided in wild-type mice: The nucleus' dorsolateral 'shell' region contains the majority of cells positive for the calcium-binding protein calbindin-D28k, and receives the strongest concentration of inputs from the superior colliculus. This subdivision remains normal in mice lacking the beta2 subunit of the nicotinic acetylcholine receptor. Although in these animals the dLGN contains fewer calbindin-positive cells, those cells are predominantly situated in the dorsolateral portion of the nucleus, and this region remains preferentially targeted by the colliculogeniculate projection.

Once sensory stimuli become able to alter firing patterns in the developing brain, they can influence the maturation of neuronal circuits. Recent experimental studies add to our understanding of precisely which developmental events are affected by early experience. In particular, it appears that experience of the external environment can affect the brain earlier in development and at earlier stages of sensory processing than previously thought. These studies emphasise the developmental importance of the patterning of neuronal firing produced either by sensory stimuli or by spontaneous activity. The timing of action potentials is also an important aspect of several exciting studies describing the mechanisms - anatomical, synaptic, and molecular - by which early experience brings about alterations in the maturation of sensory circuitry. Importantly, this kind of approach can lead to predictions concerning the nature of sensory stimulation that is most effective in instructing brain development.

We examined variation in diet choice by marten (Martes americana) among seasons and between sexes and ages from 1980-1985. During this period prey populations crashed simultaneously, except for ruffed grouse (Bonasa umbellus) which was common at the beginning and end of the study, and masked shrews (Sorex cinereus) which were abundant in 1983. Marten were catholic in selection of prey and made use of most available mammalian prey, ruffed grouse, passerine birds, berries, and insects. Diet niche was widest during the latter three years when prey was scare, particularly in late winter. Diet niche breadth was negatively correlated with abundance of all common prey species. Proportion of small prey species in the diet was correlated with absolute abundance of those species, but proportion of some large prey was related to their relative abundance. Diet choice varied among years and among seasons. Berries and insects were common in summer diets while large prey, particularly varying hare (Lepus americanus), were more frequent in winter diet than in summer diet. We found little evidence that any small mammal species was a preferred prey. Sexual size dimorphism between the sexes did not affect prey choice, nor did age. Reduced foraging effort in winter resulted in a wider diet niche only when prey was scarce. The only prediction of optimal foraging models fully supported by our data was a wider diet niche with reduced prey abundance. However, among the three most profitable prey species choice was dependent on the absolute abundance of the most profitable type (varying hare). We suggest that marten primarily forage for large prey but employ a strategy which results in encounters with small prey as well. These small prey are eaten as they provide energy at minimal cost, between captures of large prey.