Maps of bottom type are essential to the management of marine resources and biodiversity because ... more Maps of bottom type are essential to the management of marine resources and biodiversity because of their foundational role in characterizing species’ habitats. They are also urgently needed as countries work to define marine protected areas. Current approaches are time consuming, focus largely on grain size, and tend to overlook shallow waters. Our random forest classification of almost 200,000 observations of bottom type is a timely alternative, providing maps of coastal substrate at a combination of resolution and extents not previously achieved. We correlated the observations with depth, depth-derivatives, and estimates of energy to predict marine substrate at 100 m resolution for Canada’s Pacific shelf, a study area of over 135,000 km2. We built five regional models with the same data at 20 m resolution. In addition to standard tests of model fit, we used three independent data sets to test model predictions. We also tested for regional, depth, and resolution effects. We guided...
Understanding how species are distributed in the environment is increasingly important for natura... more Understanding how species are distributed in the environment is increasingly important for natural resource management, particularly for keystone and habitat forming species, and those of conservation concern. Habitat suitability models are fundamental to developing this understanding; however their use in management continues to be limited due to often-vague model objectives and inadequate evaluation methods. Along the Northeast Pacific coast, canopy kelps (Macrocystis pyrifera and Nereocystis luetkeana) provide biogenic habitat and considerable primary production to nearshore ecosystems. We investigated the distribution of these species by examining a series of increasingly complex habitat suitability models ranging from process-based models based on species' ecology to complex Generalised Additive Models applied to purpose-collected survey data. Seeking limits on model complexity, we explored the relationship between model complexity and forecast skill, measured using both cross-validation and independent data evaluation. Our analysis confirmed the importance of predictors used in models of coastal kelp distributions developed elsewhere (i.e., depth, bottom type, bottom slope, and exposure); it also identified additional important factors including salinity, and interactions between exposure and salinity, and slope and tidal energy. Comparative results showed that cross-validation can lead to over-fitting, while independent data evaluation clearly identified the appropriate model complexity for generating habitat forecasts. Our results also illustrate that, depending on the evaluation data, predictions from simpler models can out-perform those from more complex models. Collectively, the insights from evaluating multiple models with multiple data sets contribute to the holistic assessment of model forecast skill. The continued development of methods and metrics for evaluating model forecasts with independent data, and the explicit consideration of model objectives and assumptions, promise to increase the utility of model forecasts to decision makers
As science has advanced, the depth and breadth of accumulated knowledge has led to the scattering... more As science has advanced, the depth and breadth of accumulated knowledge has led to the scattering of disciplines across the landscape of worldly mysteries. Each of us strives to understand that part of the landscape where we work, using the language developed by those who arrived there before us. We are aware of work done in other parts of the landscape, but we seldom need to engage it. That is, until we realized that to effectively manage the impacts of our activities on natural systems, an interdisciplinary effort would be required. Ecosystem-based management (EBM) strives to recognize the full array of interactions within an ecosystem that includes humans. This effort is not only interdisciplinary (involving multiple scientific disciplines) but also transdisciplinary (extending beyond science to stakeholders, and others). Given the diversity of scientific disciplines and in the broader stakeholder community, communication is critical. However, in such heterogeneous groups, communication is typically confounded by jargon. This is particularly true for something as broad and all-encompassing as EBM. We argue that EBM would advance much faster, and with less conflict, if knowledge transfer between the diverse groups was improved, and learning from past experiences enhanced. To that end, we are exploring ways of standardizing how EBM knowledge is represented, and through that how EBM efforts are represented. We begin with the assertion that any EBM context can be defined in terms of Entities - ecosystem components, activities, communities, and Relationships - impacts, benefits, processes. We argue that there exists a comprehensive set of such Entities and Relationships that, along with their attributes, would be sufficient for defining any EBM context. Once defined, this ontology (EBMView) would provide a straightforward method for standardizing and integrating the knowledge held by the groups involved. It would also serve as a framework with which to build EBMBase - a searchable, analyzable repository of EBM case studies represented in EBMView. The advantages of such a standardized representation of a diverse collection of EBM applications are myriad, all stemming from improved knowledge representation. These include streamlined communication, faster knowledge transfer, increased understanding, and reduced conflict among EBM participants
The contributors describe and discuss the application of ecosystem-based management to coastal an... more The contributors describe and discuss the application of ecosystem-based management to coastal and ocean systems. The contributors describe and discuss the application of ecosystem-based management to coastal and ocean systems.
Background / Purpose: Sea otters are widely regarded as a keystone species, able to structure nea... more Background / Purpose: Sea otters are widely regarded as a keystone species, able to structure nearshore marine environments by releasing macro-algae from grazing pressure. This restructuring can shift an invertebrate-dominated nearshore system (urchin barrens) into a kelp-dominated system, which is assumed to support a greater biomass and diversity than the urchin barrens. The nearshore ecosystem on the west coast of Vancouver Island (WCVI) is experiencing these shifts because of the reintroduction of sea otters in the 70s, affecting those who depend on the natural resources. To manage this ecosystem, an integrated understanding of the ecosystem dynamics (including human interactions) is required. Main conclusion: To contribute to this, I am building an ecosystem model using Ecopath with Ecosim (EwE), software widely used for aquatic ecosystems. The model demonstrates how to represent the indirect benefits provided by kelp forest and the reintroduction of species. The results show e...
To support the development of critical habitat designations, species recovery strategies, and hab... more To support the development of critical habitat designations, species recovery strategies, and habitat-based stock assessments, comprehensive spatial maps of the physical and biological characteristics of the nearshore (0 – 50 m) region are required. This region – termed the ‘white strip’ by marine geologists because of the lack of physical data – is dynamic, highly variable, and difficult to access. Data collection is therefore patchy and expensive. With few exceptions, the habitat analyses conducted in this ecosystem are generally done over small spatial extents, at a high resolution.We have been working to develop the concept of habitat patches (HaPs) to integrate the available physical data sets describing this region. These include depth, fetch, tidal energy, and bottom type information from dive and aerial surveys, acoustic soundings, and grab samples. The resulting spatial coverage is an integrated, variable resolution, comprehensive representation of the nearshore ecosystem b...
Maps of bottom type are essential to the management of marine resources and biodiversity because ... more Maps of bottom type are essential to the management of marine resources and biodiversity because of their foundational role in characterizing species’ habitats. They are also urgently needed as countries work to define marine protected areas. Current approaches are time consuming, focus largely on grain size, and tend to overlook shallow waters. Our random forest classification of almost 200,000 observations of bottom type is a timely alternative, providing maps of coastal substrate at a combination of resolution and extents not previously achieved. We correlated the observations with depth, depth-derivatives, and estimates of energy to predict marine substrate at 100 m resolution for Canada’s Pacific shelf, a study area of over 135,000 km2. We built five regional models with the same data at 20 m resolution. In addition to standard tests of model fit, we used three independent data sets to test model predictions. We also tested for regional, depth, and resolution effects. We guided...
Understanding how species are distributed in the environment is increasingly important for natura... more Understanding how species are distributed in the environment is increasingly important for natural resource management, particularly for keystone and habitat forming species, and those of conservation concern. Habitat suitability models are fundamental to developing this understanding; however their use in management continues to be limited due to often-vague model objectives and inadequate evaluation methods. Along the Northeast Pacific coast, canopy kelps (Macrocystis pyrifera and Nereocystis luetkeana) provide biogenic habitat and considerable primary production to nearshore ecosystems. We investigated the distribution of these species by examining a series of increasingly complex habitat suitability models ranging from process-based models based on species' ecology to complex Generalised Additive Models applied to purpose-collected survey data. Seeking limits on model complexity, we explored the relationship between model complexity and forecast skill, measured using both cross-validation and independent data evaluation. Our analysis confirmed the importance of predictors used in models of coastal kelp distributions developed elsewhere (i.e., depth, bottom type, bottom slope, and exposure); it also identified additional important factors including salinity, and interactions between exposure and salinity, and slope and tidal energy. Comparative results showed that cross-validation can lead to over-fitting, while independent data evaluation clearly identified the appropriate model complexity for generating habitat forecasts. Our results also illustrate that, depending on the evaluation data, predictions from simpler models can out-perform those from more complex models. Collectively, the insights from evaluating multiple models with multiple data sets contribute to the holistic assessment of model forecast skill. The continued development of methods and metrics for evaluating model forecasts with independent data, and the explicit consideration of model objectives and assumptions, promise to increase the utility of model forecasts to decision makers
As science has advanced, the depth and breadth of accumulated knowledge has led to the scattering... more As science has advanced, the depth and breadth of accumulated knowledge has led to the scattering of disciplines across the landscape of worldly mysteries. Each of us strives to understand that part of the landscape where we work, using the language developed by those who arrived there before us. We are aware of work done in other parts of the landscape, but we seldom need to engage it. That is, until we realized that to effectively manage the impacts of our activities on natural systems, an interdisciplinary effort would be required. Ecosystem-based management (EBM) strives to recognize the full array of interactions within an ecosystem that includes humans. This effort is not only interdisciplinary (involving multiple scientific disciplines) but also transdisciplinary (extending beyond science to stakeholders, and others). Given the diversity of scientific disciplines and in the broader stakeholder community, communication is critical. However, in such heterogeneous groups, communication is typically confounded by jargon. This is particularly true for something as broad and all-encompassing as EBM. We argue that EBM would advance much faster, and with less conflict, if knowledge transfer between the diverse groups was improved, and learning from past experiences enhanced. To that end, we are exploring ways of standardizing how EBM knowledge is represented, and through that how EBM efforts are represented. We begin with the assertion that any EBM context can be defined in terms of Entities - ecosystem components, activities, communities, and Relationships - impacts, benefits, processes. We argue that there exists a comprehensive set of such Entities and Relationships that, along with their attributes, would be sufficient for defining any EBM context. Once defined, this ontology (EBMView) would provide a straightforward method for standardizing and integrating the knowledge held by the groups involved. It would also serve as a framework with which to build EBMBase - a searchable, analyzable repository of EBM case studies represented in EBMView. The advantages of such a standardized representation of a diverse collection of EBM applications are myriad, all stemming from improved knowledge representation. These include streamlined communication, faster knowledge transfer, increased understanding, and reduced conflict among EBM participants
The contributors describe and discuss the application of ecosystem-based management to coastal an... more The contributors describe and discuss the application of ecosystem-based management to coastal and ocean systems. The contributors describe and discuss the application of ecosystem-based management to coastal and ocean systems.
Background / Purpose: Sea otters are widely regarded as a keystone species, able to structure nea... more Background / Purpose: Sea otters are widely regarded as a keystone species, able to structure nearshore marine environments by releasing macro-algae from grazing pressure. This restructuring can shift an invertebrate-dominated nearshore system (urchin barrens) into a kelp-dominated system, which is assumed to support a greater biomass and diversity than the urchin barrens. The nearshore ecosystem on the west coast of Vancouver Island (WCVI) is experiencing these shifts because of the reintroduction of sea otters in the 70s, affecting those who depend on the natural resources. To manage this ecosystem, an integrated understanding of the ecosystem dynamics (including human interactions) is required. Main conclusion: To contribute to this, I am building an ecosystem model using Ecopath with Ecosim (EwE), software widely used for aquatic ecosystems. The model demonstrates how to represent the indirect benefits provided by kelp forest and the reintroduction of species. The results show e...
To support the development of critical habitat designations, species recovery strategies, and hab... more To support the development of critical habitat designations, species recovery strategies, and habitat-based stock assessments, comprehensive spatial maps of the physical and biological characteristics of the nearshore (0 – 50 m) region are required. This region – termed the ‘white strip’ by marine geologists because of the lack of physical data – is dynamic, highly variable, and difficult to access. Data collection is therefore patchy and expensive. With few exceptions, the habitat analyses conducted in this ecosystem are generally done over small spatial extents, at a high resolution.We have been working to develop the concept of habitat patches (HaPs) to integrate the available physical data sets describing this region. These include depth, fetch, tidal energy, and bottom type information from dive and aerial surveys, acoustic soundings, and grab samples. The resulting spatial coverage is an integrated, variable resolution, comprehensive representation of the nearshore ecosystem b...
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