Bruce Marcot - Academia.edu (original) (raw)
Papers by Bruce Marcot
Biological Conservation, 2015
We describe new methods for quantifying specific in-situ activities of wildlife, in this case the... more We describe new methods for quantifying specific in-situ activities of wildlife, in this case the endangered California condor (Gymnogyps californianus). These methods extract information from hundreds of thousands of temporally continuous and spatially explicit satellite telemetry reports. Visual observations and ground-based telemetry can provide behavioral data, although the information is often spatially and temporally limited and sample sizes can be small for wideranging species. Automated satellite telemetry offers continuous position reporting and unbiased spatial coverage, but to date has lacked thematic content such as the time, place, and duration of particular activities. Procedures developed for this study use a combination of models and geographic information systems (GIS) to identify condor transit flight, perching, roosting, and nesting activity based only on hourly telemetry position reports. This approach combines the temporal and spatial advantages of automated telemetry with increased thematic quality from activity models. The analytical methods were applied to 340,694 satellite-based position records from 51 California condors which were collected from June 2005 to April 2012. We identified 31,268 extended perch locations and an additional 15,483 overnight roost locations by translating basic location, speed, and time data into characterizations of bird activities. This approach correctly identified nine of the ten known nest sites occupied by condors outfitted with telemetry transmitters based only on the telemetry data. The spatial locations of these activities were mapped using GIS. This represents a significant advantage over simple location and movement data normally associated with wildlife telemetry, and is applicable to a wide range of species. considered a flagship endangered species, representing a considerable range of conservation challenges, and serves as an example of how science, captive breeding, reintroductions, and intensive management can save a species from the brink of extinction . The condor is also a good candidate for investigating how we might mine satellite telemetry data for additional information useful for applied conservation because: (1) a large number of individuals in the population are outfitted with satellite telemetry, (2) condors use a wide variety of habitats and range over large areas, and (3) the population is expanding, meaning that it will be useful to managers if we can identify where condors are performing specific activities (e.g., nesting, perching, roosting).
Statistics in Practice, 2008
Forest …, 2010
We used novel methods for combining information from wildlife and vegetation field studies to dev... more We used novel methods for combining information from wildlife and vegetation field studies to develop guidelines for managing dead wood for wildlife and biodiversity. The DecAID Decayed Wood Adviser presents data on wildlife use of standing and down dead trees (snags and down wood) and summaries of regional vegetation plot data depicting dead wood conditions, for forests across the Pacific Northwest United States. We combined data on wildlife use by snag diameter and density and by down wood diameter and cover, across studies, using parametric techniques of meta-analysis. We calculated tolerance intervals, which represent the percentage of each species' population that uses particular sizes or amounts of snags and down wood, and rank-ordered the species into cumulative species curves. We combined data on snags and down wood from Ͼ16,000 field plots from three regional forest inventories and calculated distribution-free tolerance intervals compatible with those compiled for wildlife to facilitate integrated analysis. We illustrate our methods using an example for one vegetation condition. The statistical summaries in DecAID use a probabilistic approach, which works well in a risk analysis and management framework, rather than a deterministic approach. Our methods may prove useful to others faced with similar problems of combining information across studies in other regions or for other data types. FOR. SCI. 56(4):391-404.
The Journal of Wildlife Management, 1999
Forest Ecology and Management, 2001
We analyzed effects of three land management alternatives on 31 terrestrial vertebrates of conser... more We analyzed effects of three land management alternatives on 31 terrestrial vertebrates of conservation concern within the interior Columbia river basin study area. The three alternatives were proposed in a Supplemental Draft Environmental Impact Statement (SDEIS) that was developed for lands in the study area administered by the US Department of Agriculture (USDA) Forest Service (FS) and US Department of Interior (USDA) Bureau of Land Management (BLM). To evaluate effects of these alternatives, we developed Bayesian belief network (BBN) models, which allowed empirical and hypothesized relations to be combined in probability-based projections of conditions. We used the BBN models to project abundance and distribution of habitat to support potential populations (population outcomes) for each species across the entire study area. Population outcomes were defined in five classes, referred to as outcomes A-E. Under outcome A, populations are abundant and well distributed, with little or no likelihood of extirpation. By contrast, populations under outcome E are scarce and patchy, with a high likelihood of local or regional extirpation. Outcomes B-D represent gradients of conditions between the extremes of classes A and E. Most species (65%, or 20 of 31) were associated with outcome A historically and with outcomes D or E currently (55%, or 17 of 31). Population outcomes projected 100 years into the future were similar for all three alternatives but substantially different from historical and current outcomes. For species dependent on old-forest conditions, population outcomes typically improved one outcome class -usually from E or D to D or C -from current to the future under the alternatives. By contrast, population outcomes for rangeland species generally did not improve under the alternatives, with most species remaining in outcomes C, D, or E. Our results suggest that all three management alternatives will substantially improve conditions for most forest-associated species but provide few improvements for rangeland-associated vertebrates. Continued displacement of native vegetation by exotic plants, as facilitated by a variety of human-associated disturbances, will be an on-going challenge to the improvement of future conditions for rangeland species. #
Forest Ecology and Management, 2001
We developed procedures for using Bayesian belief networks (BBNs) to model habitat and population... more We developed procedures for using Bayesian belief networks (BBNs) to model habitat and population viability of selected at-risk ®sh and wildlife species. The BBN models represent the ecological causal web of key environmental correlates (KECs) that most in¯uence habitat capability, potential population response for each species, and in¯uence of habitat planning alternatives. BBN models represent site-speci®c KECs, habitat capability at the subwatershed level, and pattern of habitat capability across all subwatersheds. BBNs use Dirichlet prior probability distributions and standard Bayesian updating of posterior probabilities. We derived estimates of prior and conditional probabilities from a mix of empirical data and expert judgment, mostly the latter. Sensitivity analyses identi®ed planning decisions and KECs that most in¯uence species outcomes, and can help prioritize monitoring activities. BBN models, however, substitute for neither ®eld studies nor empirical, quantitative population viability analyses of population demography and genetics. Published by Elsevier Science B.V.
… -habitat Relationships in …, 2001
CHAPTER 24: WOOD LEGACIES 581 as bark piles at the base of snags, hollow living trees, and broome... more CHAPTER 24: WOOD LEGACIES 581 as bark piles at the base of snags, hollow living trees, and broomed trees. Simplified classification schemes and inventory procedures have been developed for decaying wood, particularly wood habitat structures relevant to wildlife. Wildlife species associated with wood decay, and their ecosystems are affected by management activities. Intensively managed forest plantations have replaced oldgrowth throughout most of the commercial forest land base in Oregon and Washington. 41, 42 Intensive forest management regimes have substantially altered the abundance and composition (species, size, decay class) of decaying wood in forest ecosystems in the Pacific Northwest. Managed forests, on average, have lower amounts of large down wood and snags than do natural forests. 114, 344, Furthermore, in forests east of the Cascade crest, fire suppression has altered stand dynamics and produced accumulations of fine fuels conducive to stand-replacement fires. 5, 211, 302 Forest health problems and declining populations of some vertebrate and invertebrate wildlife species have coincided with changes in forest structure. These changes have raised concerns about the future biodiversity, productivity, and sustainability of the region's forests, particularly in coastal and eastside forests.
The Condor, 2007
Page 1. THIRD ED Michael L. Morrison, Bruce G* Marcot, unci R. wiJIium Mannan Wildlife-Habitat Re... more Page 1. THIRD ED Michael L. Morrison, Bruce G* Marcot, unci R. wiJIium Mannan Wildlife-Habitat Relationships Concepts and Applications it. Page 2. Page 3. ABOUT ISLAND PRESS Island Press is the only nonprofit organization ...
Canadian Journal of Forest Research, 2006
Woodland caribou (Rangifer tarandus caribou (Gmelin)) populations are in decline throughout much ... more Woodland caribou (Rangifer tarandus caribou (Gmelin)) populations are in decline throughout much of their range. With increasingly rapid industrial, recreational, residential, and agricultural development of caribou habitat, tools are required to make clear, knowledgeable, and explainable management decisions to support effective conservation of caribou and their range. We developed a series of Bayesian belief networks to evaluate conservation policy scenarios applied to caribou seasonal range recovery areas. We demonstrate the utility of the networks to articulate ecological understanding among stakeholders, to clarify and explicitly depict threats to seasonal range. We also show how simulated forecasts of spatially explicit seasonal range can be compared with landscape potential with range under assumed conditions of natural disturbance. These tools have provided opportunities to operationally define and measure conditions for recovery of caribou in north-central British Columbia.
Canadian Journal of Forest Research, 2006
... A newer optimization model called TIMPRO-FORMAN will run on IBM-compatible personal computers... more ... A newer optimization model called TIMPRO-FORMAN will run on IBM-compatible personal computers (Cooney 1987 ... These include user-friendly information bases that may be queried with English sentences and ... A users manual for HEP accounting software for microcomputers. ...
Biological Conservation, 2015
We describe new methods for quantifying specific in-situ activities of wildlife, in this case the... more We describe new methods for quantifying specific in-situ activities of wildlife, in this case the endangered California condor (Gymnogyps californianus). These methods extract information from hundreds of thousands of temporally continuous and spatially explicit satellite telemetry reports. Visual observations and ground-based telemetry can provide behavioral data, although the information is often spatially and temporally limited and sample sizes can be small for wideranging species. Automated satellite telemetry offers continuous position reporting and unbiased spatial coverage, but to date has lacked thematic content such as the time, place, and duration of particular activities. Procedures developed for this study use a combination of models and geographic information systems (GIS) to identify condor transit flight, perching, roosting, and nesting activity based only on hourly telemetry position reports. This approach combines the temporal and spatial advantages of automated telemetry with increased thematic quality from activity models. The analytical methods were applied to 340,694 satellite-based position records from 51 California condors which were collected from June 2005 to April 2012. We identified 31,268 extended perch locations and an additional 15,483 overnight roost locations by translating basic location, speed, and time data into characterizations of bird activities. This approach correctly identified nine of the ten known nest sites occupied by condors outfitted with telemetry transmitters based only on the telemetry data. The spatial locations of these activities were mapped using GIS. This represents a significant advantage over simple location and movement data normally associated with wildlife telemetry, and is applicable to a wide range of species. considered a flagship endangered species, representing a considerable range of conservation challenges, and serves as an example of how science, captive breeding, reintroductions, and intensive management can save a species from the brink of extinction . The condor is also a good candidate for investigating how we might mine satellite telemetry data for additional information useful for applied conservation because: (1) a large number of individuals in the population are outfitted with satellite telemetry, (2) condors use a wide variety of habitats and range over large areas, and (3) the population is expanding, meaning that it will be useful to managers if we can identify where condors are performing specific activities (e.g., nesting, perching, roosting).
Statistics in Practice, 2008
Forest …, 2010
We used novel methods for combining information from wildlife and vegetation field studies to dev... more We used novel methods for combining information from wildlife and vegetation field studies to develop guidelines for managing dead wood for wildlife and biodiversity. The DecAID Decayed Wood Adviser presents data on wildlife use of standing and down dead trees (snags and down wood) and summaries of regional vegetation plot data depicting dead wood conditions, for forests across the Pacific Northwest United States. We combined data on wildlife use by snag diameter and density and by down wood diameter and cover, across studies, using parametric techniques of meta-analysis. We calculated tolerance intervals, which represent the percentage of each species' population that uses particular sizes or amounts of snags and down wood, and rank-ordered the species into cumulative species curves. We combined data on snags and down wood from Ͼ16,000 field plots from three regional forest inventories and calculated distribution-free tolerance intervals compatible with those compiled for wildlife to facilitate integrated analysis. We illustrate our methods using an example for one vegetation condition. The statistical summaries in DecAID use a probabilistic approach, which works well in a risk analysis and management framework, rather than a deterministic approach. Our methods may prove useful to others faced with similar problems of combining information across studies in other regions or for other data types. FOR. SCI. 56(4):391-404.
The Journal of Wildlife Management, 1999
Forest Ecology and Management, 2001
We analyzed effects of three land management alternatives on 31 terrestrial vertebrates of conser... more We analyzed effects of three land management alternatives on 31 terrestrial vertebrates of conservation concern within the interior Columbia river basin study area. The three alternatives were proposed in a Supplemental Draft Environmental Impact Statement (SDEIS) that was developed for lands in the study area administered by the US Department of Agriculture (USDA) Forest Service (FS) and US Department of Interior (USDA) Bureau of Land Management (BLM). To evaluate effects of these alternatives, we developed Bayesian belief network (BBN) models, which allowed empirical and hypothesized relations to be combined in probability-based projections of conditions. We used the BBN models to project abundance and distribution of habitat to support potential populations (population outcomes) for each species across the entire study area. Population outcomes were defined in five classes, referred to as outcomes A-E. Under outcome A, populations are abundant and well distributed, with little or no likelihood of extirpation. By contrast, populations under outcome E are scarce and patchy, with a high likelihood of local or regional extirpation. Outcomes B-D represent gradients of conditions between the extremes of classes A and E. Most species (65%, or 20 of 31) were associated with outcome A historically and with outcomes D or E currently (55%, or 17 of 31). Population outcomes projected 100 years into the future were similar for all three alternatives but substantially different from historical and current outcomes. For species dependent on old-forest conditions, population outcomes typically improved one outcome class -usually from E or D to D or C -from current to the future under the alternatives. By contrast, population outcomes for rangeland species generally did not improve under the alternatives, with most species remaining in outcomes C, D, or E. Our results suggest that all three management alternatives will substantially improve conditions for most forest-associated species but provide few improvements for rangeland-associated vertebrates. Continued displacement of native vegetation by exotic plants, as facilitated by a variety of human-associated disturbances, will be an on-going challenge to the improvement of future conditions for rangeland species. #
Forest Ecology and Management, 2001
We developed procedures for using Bayesian belief networks (BBNs) to model habitat and population... more We developed procedures for using Bayesian belief networks (BBNs) to model habitat and population viability of selected at-risk ®sh and wildlife species. The BBN models represent the ecological causal web of key environmental correlates (KECs) that most in¯uence habitat capability, potential population response for each species, and in¯uence of habitat planning alternatives. BBN models represent site-speci®c KECs, habitat capability at the subwatershed level, and pattern of habitat capability across all subwatersheds. BBNs use Dirichlet prior probability distributions and standard Bayesian updating of posterior probabilities. We derived estimates of prior and conditional probabilities from a mix of empirical data and expert judgment, mostly the latter. Sensitivity analyses identi®ed planning decisions and KECs that most in¯uence species outcomes, and can help prioritize monitoring activities. BBN models, however, substitute for neither ®eld studies nor empirical, quantitative population viability analyses of population demography and genetics. Published by Elsevier Science B.V.
… -habitat Relationships in …, 2001
CHAPTER 24: WOOD LEGACIES 581 as bark piles at the base of snags, hollow living trees, and broome... more CHAPTER 24: WOOD LEGACIES 581 as bark piles at the base of snags, hollow living trees, and broomed trees. Simplified classification schemes and inventory procedures have been developed for decaying wood, particularly wood habitat structures relevant to wildlife. Wildlife species associated with wood decay, and their ecosystems are affected by management activities. Intensively managed forest plantations have replaced oldgrowth throughout most of the commercial forest land base in Oregon and Washington. 41, 42 Intensive forest management regimes have substantially altered the abundance and composition (species, size, decay class) of decaying wood in forest ecosystems in the Pacific Northwest. Managed forests, on average, have lower amounts of large down wood and snags than do natural forests. 114, 344, Furthermore, in forests east of the Cascade crest, fire suppression has altered stand dynamics and produced accumulations of fine fuels conducive to stand-replacement fires. 5, 211, 302 Forest health problems and declining populations of some vertebrate and invertebrate wildlife species have coincided with changes in forest structure. These changes have raised concerns about the future biodiversity, productivity, and sustainability of the region's forests, particularly in coastal and eastside forests.
The Condor, 2007
Page 1. THIRD ED Michael L. Morrison, Bruce G* Marcot, unci R. wiJIium Mannan Wildlife-Habitat Re... more Page 1. THIRD ED Michael L. Morrison, Bruce G* Marcot, unci R. wiJIium Mannan Wildlife-Habitat Relationships Concepts and Applications it. Page 2. Page 3. ABOUT ISLAND PRESS Island Press is the only nonprofit organization ...
Canadian Journal of Forest Research, 2006
Woodland caribou (Rangifer tarandus caribou (Gmelin)) populations are in decline throughout much ... more Woodland caribou (Rangifer tarandus caribou (Gmelin)) populations are in decline throughout much of their range. With increasingly rapid industrial, recreational, residential, and agricultural development of caribou habitat, tools are required to make clear, knowledgeable, and explainable management decisions to support effective conservation of caribou and their range. We developed a series of Bayesian belief networks to evaluate conservation policy scenarios applied to caribou seasonal range recovery areas. We demonstrate the utility of the networks to articulate ecological understanding among stakeholders, to clarify and explicitly depict threats to seasonal range. We also show how simulated forecasts of spatially explicit seasonal range can be compared with landscape potential with range under assumed conditions of natural disturbance. These tools have provided opportunities to operationally define and measure conditions for recovery of caribou in north-central British Columbia.
Canadian Journal of Forest Research, 2006
... A newer optimization model called TIMPRO-FORMAN will run on IBM-compatible personal computers... more ... A newer optimization model called TIMPRO-FORMAN will run on IBM-compatible personal computers (Cooney 1987 ... These include user-friendly information bases that may be queried with English sentences and ... A users manual for HEP accounting software for microcomputers. ...