A Framework for Understanding Ecological Traps and an Evaluation of Existing Evidence

When an animal settles preferentially in a habitat within which it does poorly relative to other available habitats, it is said to have been caught in an “ecological trap.” Although the theoretical possibility that animals may be so trapped is widely recognized, the absence of a clear mechanistic understanding of what constitutes a trap means that much of the literature cited as support for the idea may be weak, at best. Here, we develop a conceptual model to explain how an ecological trap might work, outline the specific criteria that are necessary for demonstrating the existence of an ecological trap, and provide tools for researchers to use in detecting ecological traps. We then review the existing literature and summarize the state of empirical evidence for the existence of traps. Our conceptual model suggests that there are two basic kinds of ecological traps and three mechanisms by which traps may be created. To this point in time, there are still only a few solid empirical examples of ecological traps in the published literature (although those few examples suggest that both types of traps and all three of the predicted mechanisms do exist in nature). Therefore, ecological traps are either rare in nature, are difficult to detect, or both. An improved library of empirical studies will be essential if we are to develop a more synthetic understanding of the mechanisms that can trigger maladaptive behavior in general and the specific conditions under which ecological traps might occur

Is Selectively Harvested Forest an Ecological Trap for Olive-Sided Flycatchers?

Disturbance-dependent species are assumed to benefit from forestry practices that mimic the appearance of postdisturbance landscapes. However, human activities that closely mimic the appearance but not the fundamental quality of natural habitats could attract animals to settle whether or not these habitats are suitable for their survival or reproduction. We examined habitat selection behavior and nest success of Olive-sided Flycatchers (Contopus cooperi) in a naturally occurring burned forest and an anthropogenically created habitat type-selectively harvested forest. Olive-sided Flycatcher density and nestling provisioning rates were greater in the selectively harvested landscape, whereas estimated nest success in selectively harvested forest was roughly half that found in naturally burned forest. Reduced nest success was probably a result of the relatively high abundance of nest predators found in the artificially disturbed forest. These results are consistent with the hypothesis that selectively harvested forest can act as an ecological trap by attracting Olive-sided Flycatchers to a relatively poor-quality habitat type. This highlights the importance of considering animal behavior in biodiversity conservation

CBLAST 2003 field work report

The long-range scientific objective of the Coupled Boundary Layer Air Sea Transfer (CBLAST) project is to observe and understand the temporal and spatial variability of the upper ocean, to identify the processes that determine that variability, and to examine its predictability. Air-sea interaction is of particular interest, but attention is also paid to the coupling of the sub-thermocline ocean to the mixed layer and to both the open ocean and littoral regimes. We seek to do this over a wide range of environmental conditions with the intent of improving our understanding of upper ocean dynamics and of the physical processes that determine the vertical and horizontal structure of the upper ocean. Field work for CBLAST was conducted during the summers of 2001, 2002, and 2003 off the south shore of Martha’s Vineyard, Massachusetts. The 2003 field work was conducted from the following platforms: heavy moorings, light moorings, drifters, F/V Nobska, CIRPAS Pelican aircraft, and an IR Cessna Aircraft. This report documents the 2003 field work and includes field notes, platform descriptions, discussion of data returns, and mooring logs. The 2003 Intensive Operating Period (IOP) was very successful and a high data return was seen.Funding was provided by the Office of Naval Research under contract numbers N00014-01-1-0029 and N00014-05-10090

Application of Design of Experiments to Flight Test: a Case Study

Modern flight test tends to be a complex, expensive undertaking so any increases in efficiency would result in considerable savings. Design of experiments is a statistical methodology which enables a highly efficient investigation where only the samples needed are collected and analyzed. the application of design of experiments to the design of flight test can result in a significant increase in test efficiency. Increased information is garnered from the data collected while the number of data points required to understand the system is reduced. in this effort, an actual flight test program serves as a case study to compare and contrast five different designs to explore the flight test envelope: the classic subject-matter-expert (SME) generated survey method, the SME-generated points augmented to a relatively fine mesh orthogonal analysis of variance design, an axial central composite design (CCD), a face-centered CCD plus simplex design, and a Simpson-Landman embedded face-centered CCD. the axial CCD is further expanded by a single point to illustrate the flexibility of the design in response to the interests of the test team. the case study data are analyzed using each designed experiment, and the results are compared and contrasted as a cost-benefit relationship between flight test resources expended (i.e. flight hours) and system understanding gained (i.e. statistical confidence and power). the design of experiments methodologies, as applied to this case study, generally show a 50 to 80 percent reduction in flight test resources expended to gain similar levels of understanding of the system under test. These savings can be applied to other programs, used to educate design changes before testing an improved system, allow for flexible investigation into areas of interest to the test team, or replicate the test points resulting in a better understanding of systemic error. in an era of restricted budgets and timelines, careful design and thoughtful analysis of flight test experiments can make the difference between a failed or cancelled flight test program and the successful fielding of a needed capability

Psychometric Properties of the Self-Efficacy for Exercise Questionnaire in a Diverse Sample of Men and Women

Background: Self-efficacy is a consistent correlate of physical activity, but most self-efficacy measures have not been validated in diverse populations. This study examined the construct, criterion-related, and convergent validity and internal consistency of the Self-Efficacy for Exercise Questionnaire. Methods: African American and Caucasian adults (N = 1919) from two adjacent counties in South Carolina were identified through a list-assisted random digit-dialed telephone survey. Psychometric properties of the measure were assessed by gender, race, age, education, and body weight subgroups. Results: Across all subgroups, a single-factor solution explained 93 to 98% of the common variance in an exploratory factor analysis, and all 14 items had factor loadings exceeding 0.40. Higher exercise self-efficacy was significantly associated with greater physical activity, younger age, male gender, higher education, and lower body weight, as predicted. Internal consistency was high for all subgroups (α = 0.90 to 0.94). Conclusion: The Self-Efficacy for Exercise Questionnaire appears to be a valid and reliable measure for use with diverse populations

Reliability of a Brief Intercept Survey for Trail Use Behaviors

Purpose: This study assessed test-retest reliability of an interviewer-administered trail survey. Methods: An intercept survey was conducted with adults using 2 paved trails in Indiana and South Carolina (N = 295; mean age = 46.9 ± 18 y). The survey included items on frequency and duration of trail use for recreation and transportation, other patterns of trail use, and sociodemographic characteristics. Fiftyfive adults completed the survey twice (2–16 d apart; mean = 7.4 ± 2.6 d). Test-retest reliability was assessed with Spearman rank correlation coefficients, Kappa coefficients, and percent agreement. Results: Kappa coefficients and percent agreement for 9 categorical items ranged from 0.65 to 0.96 and from 64.0% to 98.2%, respectively. Among these items, the lowest Kappas were found for perceived safety (0.65) and reported duration of visits for recreational purposes (0.67). Spearman rank correlation coefficients for travel distance to and on the trail and frequency of trail use during the past 7 days and past 4 weeks ranged from 0.62 to 0.93. Conclusion: Though further assessments of this survey with different populations and types of trails may be warranted, its overall high reliability indicates it can be used by researchers and practitioners in its current form

On-treatment follow-up in real-world studies of direct oral anticoagulants in atrial fibrillation: Association with treatment effects.

Background Numerous observational studies support the safety and effectiveness of the direct oral anticoagulants (DOAC) for stroke prevention in atrial fibrillation (AF), but these data are often limited to short duration of follow-up. We aimed to assess the length of on-treatment follow-up in the accumulated real-world evidence and the relationship between follow-up duration and estimates of DOAC effectiveness and safety. Methods We searched the literature for observational studies reporting comparative effectiveness and safety outcomes of DOACs versus warfarin. In random-effects meta-analyses, we assessed associations of specific DOACs vs warfarin for stroke/systematic embolism (SE) and major bleeding. In meta-regression analyses, we assessed the correlation between the reported on-treatment follow-up with the effect sizes for stroke/SE and major bleeding outcomes. Results In 45 eligible observational studies, the average on-treatment follow-up was <1 year for all DOACs. In meta-analyses, all DOACs showed significantly lower risks of stroke/SE, but only dabigatran and apixaban showed lower risks for major bleeding compared to warfarin. There was no correlation between follow-up duration and magnitude of stroke/SE reduction for any of the DOACs. Longer follow-up correlated with greater major bleeding reduction for dabigatran (p = 0.006) and rivaroxaban (p = 0.033) as compared to warfarin, but it correlated with smaller major bleeding reduction for apixaban (p = 0.004). Conclusions The numerous studies of DOAC effectiveness and safety in the routine AF practice pertain to short treatment follow-up. Study follow-up correlates significantly with DOAC-specific vs warfarin associations for major bleeding

SecNav / CBLAST 2002 field experiment deployment / recovery cruises and data report, F/V Nobska, June 19-20, 2002, F/V Nobska, September 4 and 9, 2002, mooring data, June 19 - September 9, 2002

During the summer of 2002, six surface moorings and one subsurface mooring were deployed south of Martha's Vineyard, Cape Cod, Massachusetts. The moorings were deployed from June to September 2002 to collect meteorological and oceanographic data. This was done both to support the Coupled Boundary Layered Air-Sea Transfer Low wind (CBLAST-Low) cooperative experiment and to address the question of regional predictability in the littoral regime under research supported by a Secretary of the Navy/Chief of Naval Operations (CNO) Chair. The aim was to capture the mesoscale development and response of inner shelf waters to local synoptic atmospheric, tidal and larger scale oceanic forcing under predominantly low wind conditions. This report covers the operational aspects of the 2002 experiment, including deployment, recovery, and mooring setups, as well as basic data returns.Funding was provided by the Office of Naval Research under Contract Numbers N00014-01-1-0029 and N00014-99-1-0090

A New Forest Fire Paradigm: The Need for High-Severity Fires

Forest fires, particularly those that burn at mixed and high severity (collectively called ‘severe’), have been traditionally perceived as catastrophic events, directing public attention and immense forest management budgets toward fire prevention and suppression. These fires may indeed be catastrophic when measured by losses of human lives and property. However, severe fires in wildland areas are both natural and necessary to maintain the integrity of dynamic, disturbance-adapted forest systems. We propose a change in the current paradigm—which holds that severe forest fires are always harmful—to a new one that embraces their ecological necessity