Landscape Partnership Resources Library
Seasonal Neighbors: Residential Development Encroaches on Mule Deer Winter Range in Central Oregon
Mule deer populations in central Oregon are in decline, largely because of habitat loss. Several factors are likely contributors. Encroaching juniper and invasive cheatgrass are replacing deer forage with high nutritional value, such as bitterbrush and sagebrush. Fire suppression and reduced timber harvests mean fewer acres of early successional forest, which also offer forage opportunities. Human development, including homes and roads, is another factor. It is this one that scientists with the Pacific Northwest Research Station and their collaborators investigated in a recent study. As part of an interagency assessment of the ecological effects of resort development near Bend, Oregon, researchers examined recent and potential development rates and patterns and evaluated their impact on mule deer winter range. They found that residential development in central Oregon is upsetting traditional migratory patterns, reducing available habitat, and possibly increasing stress for mule deer. Many herds of mule deer spend the summer in the Cascade Range and move to lower elevations during the winter. An increasing number of buildings, vehicle traffic, fencing, and other obstacles that accompany human land use are making it difficult for mule deer to access and use their winter habitat. The study provides valuable information for civic leaders, land use planners, and land managers to use in weighing the ecological impact of various land use decisions in central Oregon.
Thinking Big: Linking Rivers to Landscapes
Exploring relationships between landscape characteristics and rivers is an emerging field of study, bolstered by the proliferation of satellite data, advances in statistical analysis, and increased emphasis on largescale monitoring. Climate patterns and landscape features such as road networks, underlying geology, and human developments determine the characteristics of the rivers flowing through them. A multiagency team of scientists developed novel modeling methods to link these landscape features to instream habitat and to abundance of coho salmon in Oregon coastal streams. This is the first comprehensive analysis of landscape-scale data collected as part of the state’s Oregon Plan for Salmon and Watersheds. The research team found that watershed characteristics and human activities far from the river’s edge influence the distribution and habitats of coho salmon. Although large-scale landscape characteristics can predict stream reaches that might support greater numbers of coho salmon, smaller scale features and random chance also play a role in whether coho spawn in a particular stream and in a particular year. The team developed new models that successfully predicted the distribution of instream habitat features. Volume of instream wood and pool frequency were the features most influenced by human activities. Studying these relationships can help guide large-scale monitoring and management of aquatic resources.
Mount St. Helens: Still Erupting Lessons 31 Years Later
The massive volcanic eruption of Mount St. Helens 31 years ago provided the perfect backdrop for studying the earliest stages of forest development. Immediately after the eruption, some areas of the blast area were devoid of life. On other parts of the volcanic landscape, many species survived, although their numbers were greatly reduced. Reassembly began at many different starting points along the spectrum of disturbance. Within the national volcanic monument, natural regeneration generally has been allowed to proceed at its own pace. Charlie Crisafulli and Fred Swanson, scientists with the Pacific Northwest Research Station, along with numerous collaborators, have found that the sunlit environment, dominated by shrubs, herbs, and grasses that characterize early-seral ecosystems, supports complex food webs involving numerous herbivores. These biologically rich areas provide habitat for plant and animal species that are either found only in these early-seral ecosystems or reach their highest densities there. Although much of the focus of forest ecosystem management over the past 20 years in the Pacific Northwest has been on protecting old forests and hastening development of conditions associated with older forests, the research on Mount St. Helens points to the ecological value of allowing a portion of a managed landscape to develop characteristics of a complex early-seral ecosystem
Linked in: Connectiong Riparian areas to support Forest Biodiversity
Many forest-dwelling species rely on both terrestrial and aquatic habitat for their survival. These species, including rare and little-understood amphibians and arthropods, live in and around headwater streams and disperse overland to neighboring headwater streams. Forest management policies that rely on riparian buffer strips and structurebased management—practices meant to preserve habitat—address only some of these habitat needs. They generally do not consider the overland connectivity necessary for these species to successfully move across a landscape to maintain genetically diverse populations. Management in headwater areas also can affect downstream salmon habitat. Landslides and debris flows initiated in these areas can severely degrade habitat by dumping too much sediment and not enough large wood into the stream. Carefully managing sensitive headwater areas can aid not only amphibians and arthropods, but also threatened salmon populations and other forest organisms. Pacific Northwest Research Station scientists are exploring scenarios for protecting headwaters by extending riparian buffers and connecting them over ridgelines to neighboring drainages. A range of management practices designed to achieve multiple objectives may be appropriate in these protected areas to facilitate cost-effective, ecologically integrated management plans. Headwater links could piggyback on lands that are already protected and could consider such factors as sensitivity to debris flows and landslides, land ownerships and objectives, and climate change.
From Ocean to Stratosphere
Rising tropical sea surface temperatures alter atmospheric dynamics at heights of 16 kilometers or more. SCIENCE VOL 322 3 OCTOBER 2008
Seeds of Change for Restoration Ecology
FORESTS PROVIDE A WIDE VARIETY OF ECOSYSTEM SERVICES, INCLUDING PROVISIONS SUCH AS food and fuel and services that affect climate and water quality (1). In light of the increasing global population pressure, we must not only conserve, but also restore forests to meet the increasing demands for ecosystem services and goods that they provide (2). Ecological restoration has recently adopted insights from the biodiversity-ecosystem function (BEF) perspective (3). This emphasis on functional rather than taxonomic diversity (3, 4), combined with increasing acceptance of perennial, global-scale effects on the environment (5, 6) and the associated species gains and losses (“Terrestrial ecosystem responses to species gains and losses,” D. A. Wardle et al., Review, 10 June, p. 1273), may be the beginning of a paradigm shift in forest conservation and restoration ecology. As a result, we may see increased tolerance toward and the use of nonnative tree species in forests worldwide 8 JULY 2011 VOL 333 SCIENCE
Rapid Range Shifts of Species Associated with High Levels of Climate Warming
The distributions of many terrestrial organisms are currently shifting in latitude or elevation in responseto changing climate. Using a meta-analysis, we estimated that the distributions of species haverecently shifted to higher elevations at a median rate of 11.0 meters per decade, and to higher latitudes at a median rate of 16.9 kilometers per decade. These rates are approximately two and three times faster than previously reported. The distances moved by species are greatest in studies showing thehighest levels of warming, with average latitudinal shifts being generally sufficient to track temperature changes. However, individual species vary greatly in their rates of change, suggesting that the range shift of each species depends on multiple internal species traits and external drivers of change. Rapid average shifts derive from a wide diversity of responses by individual species.
Rescuing Wolves from Politics: Wildlife as a Public Trust Resource
Long-term conservation of gray wolves is possible if states recognize a legal obligation to conserve species as a public trust resource
Human Evolution Out of Africa: The Role of Refugia and Climate Change
Although an African origin of the modern human species is generally accepted, the evolutionary processes involved in the speciation, geographical spread, and eventual extinction of archaic humans outside of Africa are much debated. An additional complexity has been the recent evidence of limited interbreeding between modern humans and the Neandertals and Denisovans. Modern human migrations and interactions began during the buildup to the Last Glacial Maximum, starting about 100,000 years ago. By examining the history of other organisms through glacial cycles, valuable models for evolutionary biogeography can be formulated. According to one such model, the adoption of a new refugium by a subgroup of a species may lead to important evolutionary changes.
The Greening of Synfuels
An old, dirty technology to make transportation fuels from coal could fight global warming, say proponents. The trick is using more biomass and burying the carbon dioxide that’s generated 18 APRIL 2008 VOL 320 SCIENCE
How Does Climate Change Affect Biodiversity?
The most recent and complex bioclimate models excel at describing species’ current distributions. Yet, it is unclear which models will best predict how climate change will affect their future distributions. 8 SEPTEMBER 2006 VOL 313 SCIENCE
Not All About Consumption
Resource exploitation can lead to increased ecological impacts even when overall consumption levels stay the same 15 March 2013 VOL 339 SCIENCE
Freshwater Methane Emissions Offset the Continental Carbon Sink
Acornerstone of our understanding of the contemporary global carbon cycle is that the terrestrial land surface is an important greenhouse gas (GHG) sink (1, 2). The global land sink is estimated to be 2.6 T 1.7 Pg of C year−1 (variability T range, excluding C emissions because of deforestation) (1). Lakes, impoundments, and rivers are parts of the terrestrial landscape, but they have not yet been included in the terrestrial GHG balance (3, 4). Available data suggest, however, that freshwaters can be substantial sources of CO2 (3, 5) and CH4 (6). Over time, soil carbon reaches freshwaters by lateral hydrological transport, where it can meet several fates, including burial in sediments, further transport to the sea, or evasion to the atmosphere as CO2 or CH4 (7). CH4 emissions may be small in terms of carbon, but CH4 is a more potent GHG than CO2 over century time scales. This study indicates that global CH4 emissions expressed as CO2 equivalents correspond to at least 25% of the estimated terrestrial GHG sink.
Status and Ecological Effects of the World’s Largest Carnivores
The largest terrestrial species in the order Carnivora are wide-ranging and rare because of their positions at the top of food webs. They are some of the world’s most admired mammals and, ironically, some of the most imperiled. Most have experienced substantial population declines and range contractions throughout the world during the past two centuries. Because of the high metabolic demands that come with endothermy and large body size, these carnivores often require large prey and expansive habitats. These food requirements and wide-ranging behavior often bring them into confl ict with humans and livestock. This, in addition to human intolerance, renders them vulnerable to extinction. Large carnivores face enormous threats that have caused massive declines in their populations and geographic ranges, including habitat loss and degradation, persecution, utilization, and depletion of prey. We highlight how these threats can affect the conservation status and ecological roles of this planet’s 31 largest carnivores.
From Past to Future Warming
Analyses of past observations help to predict the human contribution to future climate change. 21 FEBRUARY 2014 VOL 343 SCIENCE
Wildlife decline and social conflict
Policies aimed at reducing wildlife-related conflict must address the underlying causes
The Global Plight of Pollinators
Wild pollinators are in decline, and managed honeybees cannot compensate for their loss. 29 MARCH 2013 VOL 339 SCIENCE
Marine Taxa Track Local Climate Velocities
Organisms are expected to adapt or move in response to climate change, but observed distribution shifts span a wide range of directions and rates. Explanations often emphasize biological distinctions among species, but general mechanisms have been elusive. We tested an alternative hypothesis: that differences in climate velocity—the rate and direction that climate shifts across the landscape—can explain observed species shifts. We compiled a database of coastal surveys around North America from 1968 to 2011, sampling 128 million individuals across 360 marine taxa. Climate velocity explained the magnitude and direction of shifts in latitude and depth much more effectively than did species characteristics. Our results demonstrate that marine species shift at different rates and directions because they closely track the complex mosaic of local climate velocities. SCIENCE VOL 341 13 SEPTEMBER 2013
Is Embracing Change Our Best Bet?
Restoration ecology and conservation biology are both under pressure to adapt to accelerated anthropogenic global change. Pristine areas free from human infl uence no longer exist and, arguably, have not for thousands of years ( 1). Major landcover transformations for agriculture affected vast territories more than 3000 years ago ( 2). Large mammal extinctions in the late Pleistocene (circa 12,000 years ago) were related to human expansion ( 3). And relocation of nowwidespread naturalized species was already happening 4230 years ago, when domestic dogs (dingos) were introduced into Australia by way of southeast Asia ( 4). Thus, humansculpted landscapes are what we have been mostly managing for millennia. Because the rate of alteration has dramatically increased over the past 200 years, those ancient localized impacts now affect most of the world. Additionally, other indirect impacts act at a planetary scale—e.g., increased carbon dioxide concentration and nitrogen deposition
Pathways for Conservation
NEXT WEEK, CONSERVATION SCIENTISTS WILL GATHER AT THE INTERNATIONAL CONGRESS FOR Conservation Biology (ICCB) in Baltimore, Maryland, to grapple with the challenges of preserving our natural world in the face of a growing and increasingly consumptive human population. The natural world provides countless services, such as clean water, protection from fl ooding, and carbon sequestration, while offering opportunities for new medicines, foods, and energy production. Yet these valuable services and opportunities are disappearing along with the species and natural areas that supply them. The needs of a growing human population must be met while conserving the planet’s natural systems. Accomplishing both will depend on making clearer connections between scientifi c results regarding issues such as biodiversity loss and the critical decisions that must be made about conditions that underlie change, such as greenhouse gas emissions and freshwater availability. The good news is that today’s conservation scientists are developing innovative tools and strategies. SCIENCE VOL 341
