18 research outputs found
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The evolution of mapping habitat for northern spotted owls (Strix occidentalis caurina): A comparison of photo-interpreted, Landsat-based, and lidar-based habitat maps
Wildlife habitat mapping has evolved at a rapid pace over the last few decades. Beginning with simple, often subjective,
hand-drawn maps, habitat mapping now involves complex species distribution models (SDMs) using
mapped predictor variables derived from remotely sensed data. For species that inhabit large geographic areas,
remote sensing technology is often essential for producing range wide maps. Habitat monitoring for northern
spotted owls (Strix occidentalis caurina), whose geographic covers about 23 million ha, is based on SDMs that
use Landsat Thematic Mapper imagery to create forest vegetation data layers using gradient nearest neighbor
(GNN) methods. Vegetation data layers derived from GNN are modeled relationships between forest inventory
plot data, climate and topographic data, and the spectral signatures acquired by the satellite. When used as predictor
variables for SDMs, there is some transference of the GNN modeling error to the final habitat map.
Recent increases in the use of light detection and ranging (lidar) data, coupled with the need to produce spatially
accurate and detailed forest vegetation maps have spurred interest in its use for SDMs and habitat mapping. Instead
of modeling predictor variables from remotely sensed spectral data, lidar provides direct measurements of
vegetation height for use in SDMs. We expect a SDM habitat map produced from directly measured predictor variables
to be more accurate than one produced from modeled predictors.
We used maximum entropy (Maxent) SDM modeling software to compare predictive performance and estimates
of habitat area between Landsat-based and lidar-based northern spotted owl SDMs and habitat maps.
We explored the differences and similarities between these maps, and to a pre-existing aerial photo-interpreted
habitat map produced by local wildlife biologists. The lidar-based map had the highest predictive
performance based on 10 bootstrapped replicate models (AUC = 0.809 ± 0.011), but the performance of
the Landsat-based map was within acceptable limits (AUC = 0.717 ± 0.021). As is common with photo-interpreted
maps, there was no accuracy assessment available for comparison. The photo-interpreted map produced
the highest and lowest estimates of habitat area, depending on which habitat classes were included
(nesting, roosting, and foraging habitat = 9962 ha, nesting habitat only = 6036 ha). The Landsat-based map
produced an estimate of habitat area that was within this range (95% CI: 6679–9592 ha), while the lidar-based
map produced an area estimate similar to what was interpreted by local wildlife biologists as nesting (i.e., high
quality) habitat using aerial imagery (95% CI: 5453–7216). Confidence intervals of habitat area estimates from
the SDMs based on Landsat and lidar overlapped.
We concluded that both Landsat- and lidar-based SDMs produced reasonable maps and area estimates for northern
spotted owl habitat within the study area. The lidar-based map was more precise and spatially similar to
what local wildlife biologists considered spotted owl nesting habitat. The Landsat-based map provided a less precise
spatial representation of habitat within the relatively small geographic confines of the study area, but habitat
area estimates were similar to both the photo-interpreted and lidar-based maps.
Photo-interpreted maps are time consuming to produce, subjective in nature, and difficult to replicate. SDMs provide
a framework for efficiently producing habitat maps that can be replicated as habitat conditions change over
time, provided that comparable remotely sensed data are available. When the SDM uses predictor variables extracted
from lidar data, it can produce a habitat map that is both accurate and useful at large and small spatial scales. In comparison, SDMs using Landsat-based data are more appropriate for large scale analyses of amounts
and general spatial patterns of habitat at regional scales.Keywords: GNN,
Landsat TM,
Northern spotted owl,
Maxent,
Species distribution modeling,
Lidar,
Habitat suitabilit
Range-Wide Declines of Northern Spotted Owl Populations in the Pacific Northwest: A Meta-Analysis
The northern spotted owl (Strix occidentalis caurina) inhabits older coniferous forests in the Pacific Northwest and has been at the center of forest management issues in this region. The immediate threats to this federally listed species include habitat loss and competition with barred owls (Strix varia), which invaded from eastern North America. We conducted a prospective meta-analysis to assess population trends and factors affecting those trends in northern spotted owls using 26 years of survey and capture-recapture data from 11 study areas across the owls\u27 geographic range to analyze demographic traits, rates of population change, and occupancy parameters for spotted owl territories. We found that northern spotted owl populations experienced significant declines of 6–9% annually on 6 study areas and 2–5% annually on 5 other study areas. Annual declines translated to ≤35% of the populations remaining on 7 study areas since 1995. Barred owl presence on spotted owl territories was the primary factor negatively affecting apparent survival, recruitment, and ultimately, rates of population change. Analysis of spotted and barred owl detections in an occupancy framework corroborated the capture-recapture analyses with barred owl presence increasing territorial extinction and decreasing territorial colonization of spotted owls. While landscape habitat components reduced the effect of barred owls on these rates of decline, they did not reverse the negative trend. Our analyses indicated that northern spotted owl populations potentially face extirpation if the negative effects of barred owls are not ameliorated while maintaining northern spotted owl habitat across their range
The past and future roles of competition and habitat in the range-wide occupancy dynamics of Northern Spotted Owls
Slow ecological processes challenge conservation. Short-term variability can obscure the importance of slower processes that may ultimately determine the state of a system. Furthermore, management actions with slow responses can be hard to justify. One response to slow processes is to explicitly concentrate analysis on state dynamics. Here, we focus on identifying drivers of Northern Spotted Owl (Strix occidentalis caurina) territorial occupancy dynamics across 11 study areas spanning their geographic range and forecasting response to potential management actions. Competition with Barred Owls (Strix varia) has increased Spotted Owl territory extinction probabilities across all study areas and driven recent declines in Spotted Owl populations. Without management intervention, the Northern Spotted Owl subspecies will be extirpated from parts of its current range within decades. In the short term, Barred Owl removal can be effective. Over longer time spans, however, maintaining or improving habitat conditions can help promote the persistence of northern spotted owl populations. In most study areas, habitat effects on expected Northern Spotted Owl territorial occupancy are actually greater than the effects of competition from Barred Owls. This study suggests how intensive management actions (removal of a competitor) with rapid results can complement a slower management action (i.e., promoting forest succession)
Range-wide sources of variation in reproductive rates of northern spotted owls
We conducted a range-wide investigation of the dynamics of site-level reproductive rate of northern spotted owls using survey data from 11 study areas across the subspecies geographic range collected during 1993–2018. Our analytical approach accounted for imperfect detection of owl pairs and misclassification of successful reproduction (i.e., at least one young fledged) and contributed further insights into northern spotted owl population ecology and dynamics. Both nondetection and state misclassification were important, especially because factors affecting these sources of error also affected focal ecological parameters. Annual probabilities of site occupancy were greatest at sites with successful reproduction in the previous year and lowest for sites not occupied by a pair in the previous year. Site-specific occupancy transition probabilities declined over time and were negatively affected by barred owl presence. Overall, the site-specific probability of successful reproduction showed substantial year-to-year fluctuations and was similar for occupied sites that did or did not experience successful reproduction the previous year. Site-specific probabilities for successful reproduction were very small for sites that were unoccupied the previous year. Barred owl presence negatively affected the probability of successful reproduction by northern spotted owls in Washington and California, as predicted, but the effect in Oregon was mixed. The proportions of sites occupied by northern spotted owl pairs showed steep, near-monotonic declines over the study period, with all study areas showing the lowest observed levels of occupancy to date. If trends continue it is likely that northern spotted owls will become extirpated throughout large portions of their range in the coming decades
Neglected diseases of neglected populations: Thinking to reshape the determinants of health in Latin America and the Caribbean
BACKGROUND: People living in poverty throughout the developing world are heavily burdened with neglected communicable diseases and often marginalized by the health sector. These diseases are currently referred to as Neglected Diseases of Neglected Populations. The neglected diseases create social and financial burdens to the individual, the family, the community, and the nation. DISCUSSION: Numerous studies of successful individual interventions to manage communicable disease determinants in various types of communities have been published, but few have applied multiple interventions in an integrated, coordinated manner. We have identified a series of successful interventions and developed three hypothetical scenarios where such interventions could be applied in an integrated, multi-disease, inter-programmatic, and/or inter-sectoral approach for prevention and control of neglected diseases in three different populations: a slum, an indigenous community, and a city with a mix of populations. SUMMARY: The objective of this paper is to identify new opportunities to address neglected diseases, improve community health and promote sustainable development in neglected populations by highlighting examples of key risk and protective factors for neglected diseases which can be managed and implemented through multi-disease-based, integrated, inter-programmatic, and/or inter-sectoral approaches. Based on a literature review, analysis and development of scenarios we visualize how multiple interventions could manage multiple disease problems and propose these as possible strategies to be tested. We seek to stimulate intra- and inter-sectoral dialogue which will help in the construction of new strategies for neglected diseases (particularly for the parasitic diseases) which could benefit the poor and marginalized based on the principle of sustainability and understanding of key determinants of health, and lead to the establishment of pilot projects and activities which can contribute to the achievement of the Millennium Development Goals
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The effects of habitat, climate, and Barred Owls on long-term demography of Northern Spotted Owls
Estimates of species' vital rates and an understanding of the factors affecting those parameters over time and space can provide crucial information for management and conservation. We used mark–recapture, reproductive output, and territory occupancy data collected during 1985–2013 to evaluate population processes of Northern Spotted Owls (Strix occidentalis caurina) in 11 study areas in Washington, Oregon, and northern California, USA. We estimated apparent survival, fecundity, recruitment, rate of population change, and local extinction and colonization rates, and investigated relationships between these parameters and the amount of suitable habitat, local and regional variation in meteorological conditions, and competition with Barred Owls (Strix varia). Data were analyzed for each area separately and in a meta-analysis of all areas combined, following a strict protocol for data collection, preparation, and analysis. We used mixed effects linear models for analyses of fecundity, Cormack-Jolly-Seber open population models for analyses of apparent annual survival (ϕ), and a reparameterization of the Jolly-Seber capture–recapture model (i.e. reverse Jolly-Seber; RJS) to estimate annual rates of population change (λ[subscript]RJS) and recruitment. We also modeled territory occupancy dynamics of Northern Spotted Owls and Barred Owls in each study area using 2-species occupancy models. Estimated mean annual rates of population change (λ) suggested that Spotted Owl populations declined from 1.2% to 8.4% per year depending on the study area. The weighted mean estimate of λ for all study areas was 0.962 (± 0.019 SE; 95% CI: 0.925–0.999), indicating an estimated range-wide decline of 3.8% per year from 1985 to 2013. Variation in recruitment rates across the range of the Spotted Owl was best explained by an interaction between total winter precipitation and mean minimum winter temperature. Thus, recruitment rates were highest when both total precipitation (29 cm) and minimum winter temperature (−9.5°C) were lowest. Barred Owl presence was associated with increased local extinction rates of Spotted Owl pairs for all 11 study areas. Habitat covariates were related to extinction rates for Spotted Owl pairs in 8 of 11 study areas, and a greater amount of suitable owl habitat was generally associated with decreased extinction rates. We observed negative effects of Barred Owl presence on colonization rates of Spotted Owl pairs in 5 of 11 study areas. The total amount of suitable Spotted Owl habitat was positively associated with colonization rates in 5 areas, and more habitat disturbance was associated with lower colonization rates in 2 areas. We observed strong declines in derived estimates of occupancy in all study areas. Mean fecundity of females was highest for adults (0.309 ± 0.027 SE), intermediate for 2-yr-olds (0.179 ± 0.040 SE), and lowest for 1-yr-olds (0.065 ± 0.022 SE). The presence of Barred Owls and habitat covariates explained little of the temporal variation in fecundity in most study areas. Climate covariates occurred in competitive fecundity models in 8 of 11 study areas, but support for these relationships was generally weak. The fecundity meta-analysis resulted in 6 competitive models, all of which included the additive effects of geographic region and annual time variation. The 2 top-ranked models also weakly supported the additive negative effects of the amount of suitable core area habitat, Barred Owl presence, and the amount of edge habitat on fecundity. We found strong support for a negative effect of Barred Owl presence on apparent survival of Spotted Owls in 10 of 11 study areas, but found few strong effects of habitat on survival at the study area scale. Climate covariates occurred in top or competitive survival models for 10 of 11 study areas, and in most cases the relationships were as predicted; however, there was little consistency among areas regarding the relative importance of specific climate covariates. In contrast, meta-analysis results suggested that Spotted Owl survival was higher across all study areas when the Pacific Decadal Oscillation (PDO) was in a warming phase and the Southern Oscillation Index (SOI) was negative, with a strongly negative SOI indicative of El Niño events. The best model that included the Barred Owl covariate (BO) was ranked 4th and also included the PDO covariate, but the BO effect was strongly negative. Our results indicated that Northern Spotted Owl populations were declining throughout the range of the subspecies and that annual rates of decline were accelerating in many areas. We observed strong evidence that Barred Owls negatively affected Spotted Owl populations, primarily by decreasing apparent survival and increasing local territory extinction rates. However, the amount of suitable owl habitat, local weather, and regional climatic patterns also were related to survival, occupancy (via colonization rate), recruitment, and, to a lesser extent, fecundity, although there was inconsistency in regard to which covariates were important for particular demographic parameters or across study areas. In the study areas where habitat was an important source of variation for Spotted Owl demographics, vital rates were generally positively associated with a greater amount of suitable owl habitat. However, Barred Owl densities may now be high enough across the range of the Northern Spotted Owl that, despite the continued management and conservation of suitable owl habitat on federal lands, the long-term prognosis for the persistence of Northern Spotted Owls may be in question without additional management intervention. Based on our study, the removal of Barred Owls from the Green Diamond Resources (GDR) study area had rapid, positive effects on Northern Spotted Owl survival and the rate of population change, supporting the hypothesis that, along with habitat conservation and management, Barred Owl removal may be able to slow or reverse Northern Spotted Owl population declines on at least a localized scale.Keywords: Northern Spotted Owl,
occupancy,
population change,
Strix varia,
Strix occidentalis caurina,
fecundity,
Barred Owl,
surviva
The Behavioral Responses of Utah Prairie Dogs (Cynomys parvidens) to Translocation
In cases where refuge acquisition or captive breeding programs are not practical or justifiable, wild caught animals are frequently translocated into areas of suitable habitat. Such management programs seldom are designed to account for the behavioral responses of translocated animals to an unfamiliar habitat, breakup of social units, and/or interactions with existing social units in the new habitat. Ongoing efforts to translocate threatened Utah prairie dogs (Cynomys parvidens) from areas where conflicts with other land uses are occurring to public land sites have met with limited success. This could be due, in part, to behavioral responses associated with disrupting social units and placing animals in an unfamiliar environment.
The purpose of this research was to test a series of hypotheses regarding the behavioral responses of Utah prairie dogs to translocation. Focal animal sampling was used to estimate the durations and frequencies of five behavioral variables and five interaction types at four treatments: control, new site, supplemental site, and new population. In Chapter 1, activity budgets were compared among control animals, animals released into a new site versus a supplemental site, and animals already present at a supplemental site. The objective was to evaluate the relative effects of new and supplemental translocations and the effects of translocations on resident animals. In Chapter 2, the frequencies of interactions were compared among these same treatments to evaluate the effects of translocation on the sociality of Utah prairie dogs as reflected by changes in the frequencies of greeting displays, dominance/subordinance displays, and amicable and agonistic interactions. Chapter 3 compares the activity budgets of animals released at a site containing natural burrows (i.e., new population) and animals released into a site containing artificial burrows (i.e., new site) to a control. Habitat measurements for these treatments were also compared to evaluate the importance of habitat characteristics typical of prairie dog colonies to translocated animals. Hotelling\u27s T2 analyses were used to compare behavioral durations between treatments and log-linear analyses were use to compare behavioral frequencies among treatments. Activity budgets were altered by translocation through tradeoffs between the amount of time spent foraging, being vigilant, exploring the unfamiliar habitat, and minimizing conspicuousness. Predicted changes in interactions frequencies as a result of translocations were not observed.
Activity budgets of animals released into the site containing natural burrows did not differ from those of control animals . The most important behavioral consideration is the effects of burrow and habitat characteristics in providing centers of activity and effective predator detection and avoidance
The past and future roles of competition and habitat in the range-wide occupancy dynamics of Northern Spotted Owls
Slow ecological processes challenge conservation. Short-term variability can obscure the importance of slower processes that may ultimately determine the state of a system. Furthermore, management actions with slow responses can be hard to justify. One response to slow processes is to explicitly concentrate analysis on state dynamics. Here, we focus on identifying drivers of Northern Spotted Owl (Strix occidentalis caurina) territorial occupancy dynamics across 11 study areas spanning their geographic range and forecasting response to potential management actions. Competition with Barred Owls (Strix varia) has increased Spotted Owl territory extinction probabilities across all study areas and driven recent declines in Spotted Owl populations. Without management intervention, the Northern Spotted Owl subspecies will be extirpated from parts of its current range within decades. In the short term, Barred Owl removal can be effective. Over longer time spans, however, maintaining or improving habitat conditions can help promote the persistence of northern spotted owl populations. In most study areas, habitat effects on expected Northern Spotted Owl territorial occupancy are actually greater than the effects of competition from Barred Owls. This study suggests how intensive management actions (removal of a competitor) with rapid results can complement a slower management action (i.e., promoting forest succession)
Swimming against the stream: investigating psychosocial flows through mindful awareness
In this paper, we extend psychosocial research methodology by integrating a breaching experiment, influenced by ethnomethodological sociology, with aspects of mindfulness practice, influenced by Buddhist traditions. We offer an empirical investigation of what happens when researcher-participants subtly ‘swim against the stream’ of normative public social conduct in a capital city setting. Our qualitative analysis explores a single case from a corpus of 172 first-person retrospective accounts of standing still and ‘doing nothing’ in a busy, public place. We investigate the qualitative aspects of how one researcher-participant arguably adopted a mindful, ‘beginner’s mind’ orientation toward the flow of psychosocial consciousness. We empirically investigate this psychosocial orientation of mindfulness by integrating Wetherell’s concept of affective-discursive practice with James’ stream of consciousness. Mindfulness offers a specific, embodied reorientation toward psychosocial flows. We discuss the methodological implications and limitations of this reorientation for psychosocial research
Range-wide declines of northern spotted owl populations in the Pacific Northwest: A meta-analysis
The northern spotted owl (Strix occidentalis caurina) inhabits older coniferous forests in the Pacific Northwest and has been at the center of forest management issues in this region. The immediate threats to this federally listed species include habitat loss and competition with barred owls (Strix varia), which invaded from eastern North America. We conducted a prospective meta-analysis to assess population trends and factors affecting those trends in northern spotted owls using 26 years of survey and capture-recapture data from 11 study areas across the owls\u27 geographic range to analyze demographic traits, rates of population change, and occupancy parameters for spotted owl territories. We found that northern spotted owl populations experienced significant declines of 6–9% annually on 6 study areas and 2–5% annually on 5 other study areas. Annual declines translated to ≤35% of the populations remaining on 7 study areas since 1995. Barred owl presence on spotted owl territories was the primary factor negatively affecting apparent survival, recruitment, and ultimately, rates of population change. Analysis of spotted and barred owl detections in an occupancy framework corroborated the capture-recapture analyses with barred owl presence increasing territorial extinction and decreasing territorial colonization of spotted owls. While landscape habitat components reduced the effect of barred owls on these rates of decline, they did not reverse the negative trend. Our analyses indicated that northern spotted owl populations potentially face extirpation if the negative effects of barred owls are not ameliorated while maintaining northern spotted owl habitat across their range