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Environmental Change Network: Current and Future Zonation PrioritizationZonation is a spatial conservation planning software tool that can take into account multiple species to create a hierarchical prioritization of the landscape. This is in contrast to other spatial conservation planning tools which may require predefined conservation targets or areas. Here, we used 199 California landbirds along with Zonation’s “core-area” algorithm to prioritize the California landscape. Species were weighted according to the California Bird Species of Special Concern criteria and probability of occurrence was discounted by distribution model and climate model uncertainty surfaces.The dataset provides priority areas for “current”...
This set of elevation models was developed to understand current (2010) conditions of San Francisco salt marshes and for input into sea-level rise prediction models. These elevation models were built by interpolating surveyed elevation points. The elevation surveys were conducted with a Leica RX1230 Real-Time Kinematic GPS which is capable of < 2 cm vertical accuracy.
The vulnerability of species at risk from climate change is recognized as an important issue in California as well as globally. Assessing vulnerability requires information on the long-term viability of populations and understanding the influences on that viability, due to environmental drivers as well as impacts of management action. We developed population-dynamic models to assess and better understand the long-term population viability of four key, tidal marsh-dependent species, under a variety of environmental conditions, including climate change impacts. In the San Francisco Estuary, each species is represented by one or more subspecies that is entirely or mainly confined to the tidal marsh habitat in the region:...
Bird community turnover for current and future climate (GFDL) based on maxent models for 198 land bird species.
These maps display the magnitude of projected future climate change in relation to the interannual variability in late 20th century CA climate. The maps show the standardized Euclidean distance between the late 20th century climate at each pixel and the future climate at each pixel. The standardization puts all of the climate variables included on the same scale and down weights changes in future climate which have had large year to year variation historically. Warmer colors indicate greater climate change and cooler colors indicate less extreme climate change.
Priority areas for conservation of tidal marsh birds given current and future environmental conditions. Maps were created using Zonation, a spatial conservation planning software tool that can take into account multiple species and scenarios to create a hierarchical prioritization of the landscape.The current (2010) and future (2030-2110) prioritization is based upon distribution and abundance models for five tidal marsh bird species which utilized avian observation data (2000 - 2009), a marsh accretion model, and physical variables (e.g. salinity, distance to nearest channel, slope, etc). Values represent the rank in which pixels were removed from the landscape using Zonation Conservation Planning software with...
In California, the near-shore area where the ocean meets the land is a highly productive yet sensitive region that supports a wealth of wildlife, including several native bird species. These saltmarshes, mudflats, and shallow bays are not only critical for wildlife, but they also provide economic and recreational benefits to local communities. Today, sea-level rise, more frequent and stronger storms, saltwater intrusion, and warming water temperatures are among the threats that are altering these important habitats.To support future planning and conservation of California’s near-shore habitats, researchers examined current weather patterns, elevations, tides, and sediments at these sites to see how they affect plants...
Salt marsh elevation and geomorphic stability depends on mineral sedimentation. Many Mediterranean-climate salt marshes along southern California, USA coast import sediment during El Niño storm events, but sediment fluxes and mechanisms during dry weather are potentially important for marsh stability. We calculated tidal creek sediment fluxes within a highly modified, sediment-starved, 1.5-km2 salt marsh (Seal Beach) and a less modified 1-km2 marsh (Mugu) with fluvial sediment supply. We measured salt marsh plain suspended sediment concentration and vertical accretion using single stage samplers and marker horizons. At Seal Beach, a 2014 storm yielded 39 and 28 g/s mean sediment fluxes and imported 12,000 and 8800...
Full Title: Environmental Change Network: Current and Projected VegetationThe current vegetation layer is derived from the vegetation map developed as part of the California Gap Analysis project. The derivation takes the California Wildlife Habitat Relationships (CWHR) habitat classification provided in the California Gap Analysis layer, generalizes the classes to a set of broader habitat types, and rasterizes it at 800 meter resolution.The future vegetation layers for both the GFDL and CCSM GCM models are derived using a random forest model of the vegetation classification. The original CWHR classification has been generalized to 12 classes for ease in modeling. Inputs to the model include eight bioclimatic variables...
Marsh accretion was modeled by ESA PWA using the Marsh-98 model, described here. The model assumes that rates of marsh plain elevation change depend on the availability of suspended sediment and organic material, water depth, and duration of inundation periods. If enough suspended sediment is available, then tidal marsh elevations can keep pace with increased inundation. Model outputs were linearly interpolated in 10-cm increments for starting elevations ranging from -3.7 to 1.7 m (relative to mean higher high water, or MHHW), and applied to a composite 5-m elevation grid (see below) for SF Bay. Results for each possible combination of projected sea level rise, sediment and organic material availability, and target...
In the Pacific Northwest, coastal wetlands support a wealth of ecosystem services including habitat provision for wildlife and fisheries and flood protection. The tidal marshes, mudflats, and shallow bays of coastal estuaries link marine, freshwater, and terrestrial habitats, and provide economic and recreational benefits to local communities. Climate change effects such as sea-level rise are altering these habitats, but we know little about how these areas will change over the next 50–100 years. Our study examined the effects of sea-level rise on nine tidal marshes in Washington and Oregon between 2012 and 2015, with the goal of providing scientific data to support future coastal planning and conservation. We compiled...
The development of sophisticated species distribution modeling techniques provides an opportunity to examine the potential effects of climate change on bird communities. Using these modeling approaches, we are relating bird data to environmental layers to generate robust predictions of current (1971–2000) and projected future species occurrence. Future bird distributions are based on regional climate model projections for the periods 2038–2070 (IPCC Scenario A2). Bird species distributions were created using the Maxent modeling technique: Maxent (Phillips et al. 2006), which is able to model non-linear responses to environmental variables. Map values represent the predicted habitat suitability; the higher the values,...
Densities for five key tidal marsh-dependent bird species were modeled using boosted regression trees (Elith et al. 2008). The models are able to fit non-linear functions between environmental variables and the presence/absence or density of a species. Map values represent the probability of occurrence of a species or the density (birds/ha). Higher values in a map indicate a higher likelihood that a species will be present at a site. Bird species modeled: Common yellowthroat, black rail, clapper rail, marsh wren, song sparrow. Model outputs: Probably of occurrence, density (birds per hectare)
The coastal region of California supports a wealth of ecosystem services including habitat provision for wildlife and fisheries. Tidal marshes, mudflats, and shallow bays within coastal estuaries link marine, freshwater and terrestrial habitats, and provide economic and recreational benefits to local communities. Climate change effects such as sea-level rise (SLR) are altering these habitats, but we know little about how these areas will change over the next 50–100 years. Our study examined the projected effects of three recent SLR scenarios produced for the West Coast of North America on tidal marshes in California. We compiled physical and biological data, including coastal topography, tidal inundation, plant...
Workshops were held in each of the 3-6 areas to present study results and solicit visits with managers over 2-3 days. In addition, stakeholder involvement was recruited at 1-3 areas to develop a decision-making tool that incorporates climate change projections in management alternatives.
Decision makers that are responsible for stewardship of natural resources face many challenges, which are complicated by uncertainty about impacts from climate change, expanding human development, and intensifying land uses. A systematic process for evaluating the social and ecological risks, trade-offs, and cobenefits associated with future changes is critical to maximize resilience and conserve ecosystem services. This is particularly true in coastal areas where human populations and landscape conversion are increasing, and where intensifying storms and sea-level rise pose unprecedented threats to coastal ecosystems. We applied collaborative decision analysis with a diverse team of stakeholders who preserve, manage,...
Maps of the probability of occurrence of tidal marsh plant species were created using generalized additive models (Hastie and Tibshirani 1990). Species modeled: Saltgrass, alkali-heath, SF Bay gumplant, jaumea, wirerush, pepperweed, giant reed, pickleweed, hard-stem tule, three-square bullrush, smooth cordgrass, California cordgrass, cattail.
Current and projected bird distribution and abundance layers, updated with new model that has better inputs. Point Blue Conservation Science assessed the effects of sea-level rise (SLR) and salinity changes on San Francisco Bay tidal marsh ecosystems. Tidal marshes are naturally resilient to SLR, in that they can build up elevation through the capture of suspended sediment and deposition of organic material (vegetation). Thus, a “bathtub” model approach is not appropriate for assessing impacts to this dynamic habitat. Rather, dynamic accretion potential can be modeled annually based on tidal inundation, sediment availability, and the rate of organic accumulation (related to salinity).Working with researchers at...
Understanding San Francisco Bay’s vulnerabilities to sea level rise is important for both biodiversity conservation and for management of public infrastructure. Coastal marshes provide essential ecosystem services such as water filtration and flood abatement while also providing important habitat for species of conservation concern. Improving our understanding of how tidal marsh habitats will be affected by sea level rise is important so that we maximize ecosystem services that coastal marshes provide and ensure that endemic populations of plants and animals persist into the future. For this project, marsh accretion was modeled by ESA PWA (http://www.pwa-ltd.com/index.html) using the Marsh-98 model, described here:...
Species richness indicates the number of different species predicted to be able to occur at a location. Maps show the projected species richness under current climate and two models of future climate conditions. Species richness is calculated by converting the predictions from maxent models into binary maps of presence and absence and summing the maps across all species. Higher values in the maps indicate where more bird species are projected to be able to occur.