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While the eddy covariance (EC) technique is a well-established method for measuring water fluxes (i.e., evaporation or 'evapotranspiration’, ET), the measurement is susceptible to many uncertainties. One such issue is the potential underestimation of ET when relative humidity (RH) is high (>70%), due to low-pass filtering with some EC systems. Yet, this underestimation for different types of EC systems (e.g. open-path or closed-path sensors) has not been characterized for synthesis datasets such as the widely used FLUXNET2015 dataset. Here, we assess the RH-associated underestimation of latent heat fluxes (LE, or ET) from different EC systems for 163 sites in the FLUXNET2015 dataset. We found that the LE underestimation is most apparent during hours when RH is higher than 70%, predominantly observed at sites using closed-path EC systems, but the extent of the LE underestimation is highly site-specific. We then propose a machine learning based method to correct for this underestimation, and compare it to two energy balance closure based LE correction approaches (Bowen ratio correction, BRC, and attributing all errors to LE). Our correction increases LE by 189% for closed-path sites at high RH (>90%), while BRC increases LE by around 30% for all RH conditions. Additionally, we assess the influence of these corrections on ET-based transpiration (T) estimates using two different ET partitioning methods. Results show opposite responses (increasing vs. slightly decreasing T-to-ET ratios, T/ET) between the two methods when comparing T based on corrected and uncorrected LE. Overall, our results demonstrate the existence of a high RH bias in water fluxes in the FLUXNET2015 dataset and suggest that this bias is a pronounced source of uncertainty in ET measurements to be considered when estimating ecosystem T/ET and WUE.

A 2012 attempt to remove two rat species (Rattus tanezumi and R. exulans) from Wake Atoll was partially successful. R. tanezumi was eradicated from all three islands (Wake, Wilkes, and Peale), and R. exulans was eradicated from Peale. However, R. exulans remained on Wake and Wilkes and have since recovered to very high densities. In 2013, a panel of experts reviewed the eradication operation and offered a list of possible causes of the partial failure. Since that time, further research has been conducted to address several of the issues identified in the review. In this paper, we conduct a current review of the remedial studies, identify remaining knowledge gaps, and make recommendations for ensuring the feasibility of a future operation to remove R. exulans from Wake and Wilkes Islands.

Island rodent eradication operations have been remarkably successful at eliminating damages caused by these harmful vertebrate pests. As efforts increase in scale and complexity, so does risk of eradication failure. In this paper we present the example of a partially successful rodent eradication project to highlight how best practices and lessons learned are being integrated to reduce risk of failure during a second attempt. In 2012 the U.S. Air Force (USAF) commissioned an attempted eradication of two rat species from Wake Atoll in the Western Pacific. Asian house rats were successfully eradicated, but it was soon confirmed that some Polynesian rats survived; population numbers have since soared. A panel of outside experts was asked to review the project and identify factors that may have contributed to failure. The USAF and Wildlife Services National Wildlife Research Center (NWRC) have used this report as a road map for further studies addressing issues including bait delivery strategies, bait application rates, and alternate bait formulations. A subsequent data gap analysis conducted by USAF, NWRC, and Island Conservation documented technical advances in the intervening years that address risk factors identified in the original review, and highlighted remaining needs including development of a community outreach component and refinement of baiting strategies for inhabited areas and abandoned structures. This exchange of knowledge and expertise among cooperating organizations is helping to refine feasibility assessments and address lingering knowledge gaps. These efforts include a review of other failed rodent eradications that were redone successfully. Ongoing studies continue to resolve areas of uncertainty, and results are being integrated into operational planning for a subsequent eradication effort on Wake Atoll. This process highlights the importance of ongoing refinement of best practices, incorporation of lessons learned, and transfer of knowledge to the wider eradication community.

Objective: Increasing reliance on numerical simulation models to help inform management and restoration choices benefits from careful consideration of critical early steps in model development. Along the northern coast of the Gulf of Mexico, the eastern oyster Crassostrea virginica fulfills important ecological and economic roles. Using the eastern oyster as an example, we draw on several recent frameworks outlining best practices for model development and application for restoration, conservation, and management. Methods: We identify priority model questions, outline a conceptual ecological model (CEM) to guide numerical model development, and use this framework to identify uncertainties and research needs. Result: The CEM uses a nested design, identifying explicit vital rates, processes, attributes, and outcomes for the species (oysters), population, and metapopulation (i.e., network of populations) levels in response to drivers of species, population, and metapopulation changes and changing environmental factors. Most management actions related to oyster restoration and harvest affect population attributes directly, but many coastal management actions and changes (i.e., climate change and coastal and water resource engineering) impact environmental factors that alter vital rates and attributes of oysters, populations, and metapopulations. Conclusion: Investment in studies targeting individual oyster‐ and population‐level multi‐stressor responses (filtration, respiration, growth, and reproduction) and improving hydrodynamic and environmental models targeting drivers that influence metapopulation vital rates and attributes (i.e., connectivity and substrate persistence) would contribute to reducing uncertainties. Development of numerical models covering the entire oyster life cycle and connectivity of populations using hydrodynamic models of current and predicted conditions to provide key abiotic and biotic factors influencing larval movement, recruitment, and on‐reef oyster vital rates would assist in balancing the goals of conservation, restoration, and fisheries management of this foundational estuarine species. Impact statementManaging fisheries species of conservation, production, and habitat value relies increasingly on the development of numerical models. We develop a tiered conceptual ecosystem model to guide model development for the eastern oyster and to highlight key uncertainties in vital rates and outcomes. This tiered approach provides a flexible framework to guide numerical model development, and highlight key uncertainties influencing modeled outputs. [ABSTRACT FROM AUTHOR]

Background: The American Academy of Orthopaedic Surgeons (AAOS) has developed a clinical practice guideline (CPG) for management of anterior cruciate ligament (ACL) injuries. Primary studies such as randomized controlled trials (RCTs) are cited as evidence for the guidelines. Given the influence that these trials have on patient care, adherence to standardized protocols for conducting and reporting RCTs is essential. Purpose: To evaluate the CONSORT (Consolidated Standards of Reporting Trials) Extension for Harms–related reporting of RCTs cited as supporting evidence for the AAOS CPG on the management of ACL tears. Study Design: Cross-sectional study. Methods: The reference section of the AAOS guideline for ACL tears was first screened for RCTs cited in the CPG. Next, each RCT was evaluated for adherence to the CONSORT Extension for Harms checklist. Both identification of RCTs and assessment of adherence were performed in a masked and duplicate process. Descriptive statistics were used to summarize adherence to CONSORT Extension for Harms items. A Pearson correlation test was conducted to assess the relationship between the year of publication and adherence to CONSORT harms reporting. Results: The sample included 113 RCTs, of which 16 (14.2%) were published before the CONSORT Extension for Harms was implemented in 2004. Sample sizes ranged from 24 to 4564 participants, with a mean of 228. None of the included RCTs included all 18 items in the CONSORT Extension for Harms checklist. The mean number of checklist items reported was 4 (of 18; 22.2%). A moderate, positive, and statistically significant correlation was found between the RCT publication year and the adherence with reporting of the CONSORT Extension for Harms (t 111 = 3.54; P <.001) (r = 0.32; 95% CI, 0.14-0.47). Conclusion: Harms were infrequently reported in RCTs cited as supporting evidence in the AAOS CPG for the management of ACL tears. One encouraging finding was the positive correlation between the year when RCTs were published and how well they adhered to reporting harms. Efforts to improve adverse event reporting are warranted, as RCTs are commonly used to make clinical decisions in orthopaedic surgery. [ABSTRACT FROM AUTHOR]

Rodent eradications undertaken on tropical islands have had a lower success rate than those attempted in temperate regions. A recent project undertaken to eradicate Rattus tanezumi and R. exulans from the 3 islands comprising Wake Atoll is illustrative. R. tanezumi was successfully removed from all 3 islands. R. exulans was permanently eradicated on Peale Island (95 ha) and temporarily on Wilkes Island (76 ha). R. exulans eradication on Wake Island (525 ha) was unsuccessful and the species has since repopulated Wake Island and recolonized Wilkes Island. We completed a detailed review of the project in an attempt to isolate potential causes of eradication failure. Based on the evidence available, we were not able to positively identify a single factor to explain why R. exulans survived on Wake Island. However, monitoring after the operation points to a sequence of events that comprised delayed mortality amongst a subset of breeding females and the emergence of young rats after bait was no longer readily available. Such an event was likely influenced by an abundance of natural food resources throughout the treatment area, a high density of rats, interspecific competition for toxic bait, and rapid disappearance of bait because of consumption by non-target consumers (land crabs). These factors are common to many tropical islands. We provide recommendations for addressing these factors in a future attempt to remove rats from Wake Atoll.

Feral cats have significant negative impacts on island ecosystems and are a major threat to resident seabird populations. In an attempt to restore populations of Brandt’s Cormorants, western gulls, and other native species on San Nicolas Island, California, feral cats were targeted for eradication. In over 83 successful feral cat eradications from islands, removal by padded leg-hold traps was the most commonly used eradication technique. However, the size of San Nicolas, 5,896 ha (14,562 acres) and the presence of >600 diminutive (average 1.7 kg) endemic island fox presented challenges. A telemetry-based trap monitoring system was developed to remotely check trap status, decrease staff time spent checking traps, and decrease response time to captured animals to limit fox injuries and mortalities due to exposure. This system enabled a team of 6 staff to maintain daily checks of approximately 250 traps and have a response time to captures of

Feral cats are considered one of the most detrimental invasive species within island ecosystems. Non-native feral cats have been on San Nicolas Island (5,896 ha, or 14,562 acres) since at least 1952. In an effort to counter the negative impacts of feral cats on marine and terrestrial birds, the San Nicolas seabird restoration project, with the goal of eradicating cats, was initiated in June 2009. Although aimed at seabird restoration, feral cat eradication is expected to aid in the protection of endemic terrestrial species, including the federally threatened island night lizard, federally threatened western snowy plover, a subspecies of deer mouse, and the state threatened island fox. Methods including the use of altered padded leg-hold live traps, detection dogs, and hunting are being utilized to deliver a successful eradication within a short window of opportunity. In addition, a trap monitoring system, operated in tandem with field PCs and GIS, has proven effective in managing large numbers of traps. Since initiation, a rotation of staff has provided an average of 6 field personnel on-island at any one time to staff the project continuously over 10 months. Eradication was complicated by the similarly sized island fox, rugged topography, restricted access to parts of the island by Navy activities, marine mammal presence on the beaches, and sea and shore birds nesting and roosting. Island eradications require multiple methods to effectively remove all cats, and operations on larger islands benefit from the intensive use of management tools such as GIS. The systems developed on the San Nicolas Seabird Restoration Project will advance the global effort to reduce the threats of invasive species, particularly feral cats.

The author, chairman of the Department of Sociology and Social Work at Casper College in Casper, Wyoming, examines how the proportion of students who participate in schooling as a real--as opposed to a virtual--undertaking has shrunk through the growth of online courses. This situation could be a tragedy or it could be acceptable. At the moment, we do not know. Little research is conducted on the meaning of the campus experience; we have been left to simply watch it disappear, without the ability to comprehend the consequence of its absence. This article examines how we came to where we stand today in terms of the valuation of spending time within the walls and on the grounds of our institutions. The author suggests shifting efforts in outcomes assessment toward the question of what it means to spend real time with classmates, and a teacher, in the name of education.

In the past 20 years, scholars and practitioners have committed to measuring the cognitive outcomes of education. In this chapter, the author assesses the movement that focuses on cognition, to the exclusion of other outcomes. An identity-based framework is offered as an alternative.

This chapter describes some of the forces that worked to move the 2-year college away from the liberal arts and toward vocational programs. The analysis centers on agencies that made job training a priority.