Targeted threatened species management is a central component of efforts to prevent species extinction. Despite the development of a range of management frameworks to improve conservation outcomes ...over the past decade, threatened species management is still commonly characterised as ad hoc. Although there are notable successes, many management programs are ineffective, with relatively few species experiencing improvements in their conservation status. We identify underlying factors that commonly lead to ineffective and inefficient management. Drawing attention to some of the key challenges, and suggesting ways forward, may lead to improved management effectiveness and better conservation outcomes. We highlight six key areas where improvements are needed: 1) stakeholder engagement and communication; 2) fostering strong leadership and the development of achievable long-term goals; 3) knowledge of target species' biology and threats, particularly focusing on filling knowledge gaps that impede management, while noting that in many cases there will be a need for conservation management to proceed initially despite knowledge gaps; 4) setting objectives with measurable outcomes; 5) strategic monitoring to evaluate management effectiveness; and 6) greater accountability for species declines and failure to recover species to ensure timely action and guard against complacency. We demonstrate the importance of these six key areas by providing examples of innovative approaches leading to successful species management. We also discuss overarching factors outside the realm of management influence that can help or impede conservation success. Clear recognition of factors that make species' management more straightforward – or more challenging – is important for setting realistic management objectives, outlining strategic action, and prioritising resources. We also highlight the need to more clearly demonstrate the benefit of current investment, and communicate that the risk of under-investment is species extinctions. Together, improvements in conservation practice, along with increased resource allocation and re-evaluation of the prioritisation of competing interests that threaten species, will help enhance conservation outcomes for threatened species.
•Threatened species conservation is marred by ineffective and inefficient management.•Poor project planning, stakeholder engagement and leadership inhibit conservation.•Better management requires clear objectives and improved monitoring and accountability.•Shifts in societal values are needed to improve the conservation of some species.
The development of models of marine ecosystems in the Southern Ocean is becoming increasingly important as a means of understanding and managing impacts such as exploitation and climate change. ...Collating data from disparate sources, and understanding biases or uncertainties inherent in those data, are important first steps for improving ecosystem models. This review focuses on seals that breed in ice habitats of the Southern Ocean (i.e. crabeater seal, Lobodon carcinophaga; Ross seal, Ommatophoca rossii; leopard seal, Hydrurga leptonyx; and Weddell seal, Leptonychotes weddellii). Data on populations (abundance and trends in abundance), distribution and habitat use (movement, key habitat and environmental features) and foraging (diet) are summarised, and potential biases and uncertainties inherent in those data are identified and discussed. Spatial and temporal gaps in knowledge of the populations, habitats and diet of each species are also identified.
When estimating the size of seabird populations, count data may be biased due to various factors such as detection probability. Failing to account for detection probability in surveys may lead to an ...underestimate of population size and may compromise the ability to monitor trends if detection probability varies among surveys. Here, we use the double-observer method to estimate detection probability of cavity-nesting snow petrels (
Pagodroma nivea
) and Wilson’s storm petrels (
Oceanites oceanicus
) in East Antarctica. Estimates of single-visit detection probability of nesting/roosting adult snow petrels during the incubation stage of the breeding cycle ranged from 0.86 (SE = 0.04) to 0.87 (SE = 0.04) depending upon observers. Both observers found snow petrel chicks were easier to detect than adults, with estimated detection probability for chicks ranging from 0.92 (SE = 0.03) to 1.00 (SE = 0.34 × 10
−5
). Detection probability of adult and chick snow petrels increased as cavity volume increased. Compared to snow petrels, estimated detection probability was considerably lower for nesting/roosting Wilson’s storm petrels, ranging from 0.27 (SE = 0.09) to 0.50 (SE = 0.13) for each observer. These estimates of detection probability apply only to those individuals in the population that were potentially viewable or audible. Nevertheless, our results indicate that double-observer counts for ground surveys of cavity-nesting seabirds should improve estimates of population abundance in comparison with single-visit counts. Accounting for observer effects, habitat characteristics and stage of the breeding season on detection probability should also improve estimation of population trends.
Background:
Maximal safe resection is a primary objective in the management of gliomas. Despite this, surgeons and referring physicians may, on the basis of radiologic studies alone, assume a glioma ...to be unresectable due to its proximity to areas of presumed functional eloquence. Because non-invasive studies, including functional MRI, may not localize brain functions, such language, with particularly high fidelity, this simplistic approach may exclude some patients from what could be a safe resection. Intraoperative direct electrical stimulation (DES) allows for the accurate localization of functional areas, thereby enabling maximal resection of tumors, including those that may appear inoperable based solely on radiologic studies. Here we describe the extent of resection and functional outcomes following resections of tumors deemed inoperable by referring physicians and neurosurgeons.
Methods:
We retrospectively examined the cases of 58 adult patients who underwent glioma resections within six months of undergoing brain biopsies of supposedly inoperable gliomas at outside hospitals. We characterized the extent of resection and six-month functional outcomes for this population.
Results:
Intraoperative DES mapping was performed on 96.6% of patients (56 of 58). Nearly half of patients (46.6%, 27 of 58) underwent an awake surgical procedure with DES. Overall, the mean extent of resection was 87.6% ± 13.6% (range, 39.0% to 100%). Gross total resection (resection of >99% of the pre-operative tumor volume) was achieved in 29.3% of patients (17 of 58). Sub-total resection (95-99% resection) and partial resection (<95% resection) were achieved in 12.1% (7 of 58) and 58.6% of patients (34 of 58), respectively. Of the cases that involved partial resection, the mean extent of resection was 79.4% ± 12.2%. Six months after surgery, no patient was found to have a new post-operative neurologic deficit. The majority of patients (87.9%, 51 of 58) were free of neurologic deficits both pre- and post-operatively. The remainder of patients exhibited either residual but stable deficits (5.2%, 3 of 58), or complete correction of pre-operative deficits (6.9%, 4 of 58).
Conclusions:
The use of DES enabled maximal safe resections of tumors that were deemed inoperable by referring physicians and neurosurgeons. With rare exceptions, the resectability of a glioma cannot be determined solely by radiologic studies.
Wild canids (Canis lupus familiaris, C. l. dingo, C. l. familiaris × l. dingo and Vulpes vulpes) are considered to be major pests in several Australian land tenures. Although a suite of tools is ...available to reduce the impact of these vertebrate carnivores, the drivers and barriers that influence participation in management and adoption of new management tools are poorly understood. We therefore surveyed public and private land managers, both to record their perceptions toward wild canid management and to identify the social forces that influence the adoption of a new toxin, para-aminopropiophenone (PAPP). The results of the survey demonstrate that PAPP is well placed to overcome barriers to participation in wild canid management. The humaneness of PAPP in relation to target and non-target species, as well as the presence of an antidote, BlueHealer®, appealed to both private and public land managers. However, the adoption of PAPP will not be influenced solely by marketing these features of the toxin. The adoption of PAPP and new pest management tools in general will likely be influenced by beliefs toward the role of pest animals in the ecosystem, neighbour participation in management, and co-ordination of management across land tenures.
Quantifying prey consumption by top predators is a crucial component of ecosystem-based management in the Southern Ocean. In this study, we developed a bioenergetics model to estimate prey ...consumption by a top predator, the Adélie penguin Pygoscelis adeliae. Our model predicts prey consumption throughout the breeding season and incorporates uncertainty in model parameters using Monte Carlo simulation. The model was parameterized with data obtained at Béchervaise Island, the site of a long-term monitoring program in East Antarctica. We parameterized the model (1) using 13 yr of penguin population data, (2) for a year in which penguins successfully reared their chicks (2001−2002) and (3) for a year with low breeding success (1998−1999). Daily per capita energy consumption during the breeding season averaged 4269 kJ d−1 (95% CI: 4187−4352 kJ d−1) and 4684 kJ d−1 (95% CI: 4596−4771 kJ d−1) for males and females, respectively. Over the entire breeding season a male breeder consumes 470 MJ (95% CI: 461−479 MJ) compared to 515 MJ (95% CI: 506−525 MJ) for a female. On average, the Béchervaise Island population of 1836 breeding pairs consumes 16 447 MJ d−1 which amounts to 1 809 224 MJ during the breeding season. On the basis of variable breeding success and the proportion of krill and fish in their diet, we estimate that this population consumes 78 to 406 t of krill and 4 to 46 t of fish each breeding season. Our results demonstrate clear periods of peak consumption associated with the penguins’ breeding cycle.
The effect of varying the amount of inlet air swirl on the stability of the flow patterns in a small-scale, co-current spray dryer has been investigated. The objective of this work was better ...understanding of the effect of the vane angle on the flow patterns and to determine whether a particular vane angle provided superior performance. The dryer studied was a cylinder on cone unit, with a drying chamber 0.8 m in diameter and 1.61 m tall, and fitted with adjustable swirl vanes tightly surrounding a Delavan GA1 two-fluid atomiser. Swirl vane angles between 0° and 45°, in 5° increments, were investigated using a complementary combination of flow visualisation and laser Doppler velocimetry (LDV) techniques. No single swirl vane angle resulted in behaviour that was clearly steady throughout the dryer, but a swirl vane angle of about 25° was considered to be an appropriate selection. This vane angle, corresponding to a Swirl number of approximately 0.45, gave an observable degree of stability in much of the flow domain and good air-spray mixing without excessive spreading of the spray cloud and wall deposition. The introduction of spray had a significant effect on the flow behaviour, so that air-only studies did not adequately represent the flow conditions with spray.
Experiments have been performed on a pilot scale, cylinder-on-cone spray dryer fitted with a vaned-wheel atomiser to observe air flow patterns, with and without water spray. A combination of tufts, ...smoke streams and a laser light sheet, was used to provide information about regions of recirculation, flow stability, spray trajectories and wall deposition. While atomiser-induced swirl dominated the flow patterns under typical operating conditions, some instability was observed, although different in type, for situations with and without atomiser rotation. Clockwise eddies were observed to form and collapse between the wall and the strongly anti-clockwise swirling core created by anti-clockwise atomiser rotation. Without swirl, large portions of the recirculation zones at the walls were observed to have a weak tendency to change randomly between clockwise, anticlockwise and chaotic behaviour.
The inlet region of a pilot-scale, co-current spray dryer was simulated using the proprietary Computational Fluid Dynamics (CFD) codes, CFX4 and CFX5. Several design alternatives were considered for ...correcting uneven inlet air distribution, which is known to influence spray dryer performance and airflow patterns. The simulations were used to assess each alternative prior to construction, assuming isothermal and incompressible flow conditions. Experimental measurements were compared with the simulation results for the original and one modified design.
Drying air is supplied to this dryer via an overhead pipe feeding an annular plenum chamber, of diameter 400 mm, surrounding the atomiser. A distributor plate with two concentric rings of 50 holes, each of 5 mm diameter, forms the base of the plenum chamber. A three-dimensional grid was required to model each of the 100 holes separately and to consider the asymmetric flow behaviour. The resulting grid consisted of about 532,000 cells. The CFD simulations proved useful in predicting the trends in flow distributions in each of the designs.
Zbicinski
et al.
1 reported that increasing the inlet turbulence levels in a small tunnel dryer with the aim of process intensification resulted in an increase in drying performance using sprays ...consisting entirely of water. A pair of experiments for each set of conditions was produced by varying the inlet turbulence intensity in the second experiment while holding other conditions constant. The results of three such pairs of experiments have been studied using the computational fluid dynamics code, CFX4. The effects of varying several model parameters and conditions were considered in order to investigate the sensitivity of the model for this problem. Although the simulations consistently predicted levels of cumulative evaporation substantially below the measured values, increased cumulative evaporation was always predicted when inlet turbulence was enhanced. The simulations predicted improvements of between 5 and 11%, which are significantly less than the measured maximum improvement of 16.6% for these cases.
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