David J. Lawrence

National Park Service | NPS · Climate Change Response Program

Large-river decision makers are charged with maintaining diverse ecosystem services through unprecedented social-ecological transformations as climate change and other global stressors intensify. The interconnected, dendritic habitats of rivers, which often demarcate jurisdictional boundaries, generate unique complex management challenges. Here, w...

Anticipating and managing climate-induced ecosystem transformations in large rivers is particularly challenging given their inherently complex socio-ecological dynamics that often cross jurisdictional boundaries. We examine how the Resist-Accept-Direct (RAD) framework can facilitate informed decision making and a more cohesive and proactive approac...

Biological invasions represent an important and unique case of ecological transformation that can strongly influence species and entire ecosystems. Challenges in managing invasions arise on multiple fronts, ranging from diverse and often divergent values associated with native and introduced species, logistical constraints, and transformation via o...

Fisheries management is a complex task made even more challenging by rapid and unprecedented socioecological transformations associated with climate change. The Resist‐Accept‐Direct (RAD) framework can be a useful tool to support fisheries management in facing the high uncertainty and variability associated with aquatic ecosystem transformations. H...

Natural resource managers worldwide face a growing challenge: Intensifying global change increasingly propels ecosystems toward irreversible ecological transformations. This nonstationarity challenges traditional conservation goals and human well-being. It also confounds a longstanding management paradigm that assumes a future that reflects the pas...

Earth is experiencing widespread ecological transformation in terrestrial, freshwater, and marine ecosystems that is attributable to directional environmental changes, especially intensifying climate change. To better steward ecosystems facing unprecedented and lasting change, a new management paradigm is forming, supported by a decision-oriented f...

Resource managers face mounting challenges when it comes to the implementation of climate change adaptation strategies. Novel adaptation strategies, such as managed relocation, frequently entail embracing substantial risk of unintended harm to the focal ecosystems, in an effort to alleviate serious threats to biological diversity (e.g. extinction)....

Scenario planning has emerged as a widely used planning process for resource management in situations of consequential, irreducible uncertainty. Because it explicitly incorporates uncertainty, scenario planning is regularly employed in climate change adaptation. An early and essential step in developing scenarios is identifying “climate futures”—de...

Ecosystem transformation involves the emergence of persistent ecological or social–ecological systems that diverge, dramatically and irreversibly, from prior ecosystem structure and function. Such transformations are occurring at increasing rates across the planet in response to changes in climate, land use, and other factors. Consequently, a dynam...

Executive Summary Changing climate and introduced species are placing an increasing number of species at risk of extinction. Increasing extinction risk is increasing calls to protect species by relocating, or translocating, them to locations with more favorable biotic or climatic conditions. Managed relocation, or assisted migration, of species ent...

Assessing the vulnerability of species to climate change serves as the basis for climate‐adaptation planning and climate‐smart conservation, and typically involves an evaluation of exposure, sensitivity, and adaptive capacity (AC). AC is a species’ ability to cope with or adjust to changing climatic conditions, and is the least understood and most...

Ecosystem transformation can be defined as the emergence of a self‐organizing, self‐sustaining, ecological or social–ecological system that deviates from prior ecosystem structure and function. These transformations are occurring across the globe; consequently, a static view of ecosystem processes is likely no longer sufficient for managing fish, w...

The National Park Service (NPS) manages hundreds of parks in the United States, and many contain important aquatic ecosystems and/or threatened and endangered aquatic species vulnerable to hydro-climatic change. More effective management of park resources under future hydro-climatic uncertainty requires information on both baseline conditions and t...

Non‐native Smallmouth Bass Micropterus dolomieu are increasingly sympatric with juvenile spring Chinook Salmon Oncorhynchus tshawytscha in rivers of western North America. Understanding the potential effects of introduced Smallmouth Bass is essential to efficiently direct salmon management efforts, especially given the potential for upstream range...

Assessing flood risk using stationary flood frequency analysis techniques is commonplace. However, it is increasingly evident that the stationarity assumption of these analyses does not hold as anthropogenic climate change could shift a site’s hydroclimate beyond the range of historical behaviors. We employ nonstationary flood frequency models usin...

The US National Park Service has embraced participatory scenario planning as core process for conducting climate change adaptation. Here, we describe how NPS uses scenario planning, use of climate futures, and a range of approaches from "scenario lite" through an intensive, deep-dive scenario driven adaptation process.

Brown trout (Salmo trutta) are widely introduced in western North America where their presence has led to declines of several native species. To assist conservation efforts aimed at early detection and eradication of this species, we developed a quantitative PCR marker to detect the presence of brown trout DNA in environmental samples. The marker s...

Many ecologists have called for mechanism‐based investigations to identify the underlying controls on species distributions. Understanding these controls can be especially useful to construct robust predictions of how a species range may change in response to climate change or the extent to which a non‐native species may spread in novel environment...

Development of skills in science communication is a well-acknowledged gap in graduate training, but the constraints that accompany research (limited time, resources, and knowledge of opportunities) make it challenging to acquire these proficiencies. Furthermore, advisors and institutions may find it difficult to support graduate students adequately...

Predicting how climate change is likely to interact with myriad other stressors that threaten species of conservation concern is an essential challenge in aquatic ecosystems. This study provides a framework to accomplish this task in salmon-bearing streams of the northwestern United States, where land-use related reductions in riparian shading have...

1. Smallmouth bass ( Micropterus dolomieu ) have been widely introduced to fresh waters throughout the world to promote recreational fishing opportunities. In the Pacific Northwest (U.S.A.), upstream range expansions of predatory bass, especially into subyearling salmon‐rearing grounds, are of increasing conservation concern, yet have received litt...

Background/Question/Methods Humans have a rich history of introducing piscivorous non-native fishes to provide food subsidies and support recreational fishing opportunities in freshwater ecosystems throughout the world. Smallmouth bass (Micropterus dolomieu), a cool-water fish native to central North America, provide a compelling example of the p...

Climate change will likely have profound effects on cold-water species of freshwater fishes. As temperatures rise, cold-water fish distributions may shift and contract in response. Predicting the effects of projected stream warming in stream networks is complicated by the generally poor correlation between water temperature and air temperature. Spa...

We assessed the representation of freshwater fish diversity provided by the National Park Service (NPS) and the potential for parks to serve as freshwater protected areas (FPAs) in the United States. Although most parks were not designed with freshwater conservation in mind, nearly two-thirds (62%) of native U.S. fishes reside in national parks. Ho...

Smallmouth bass (Micropterus dolomieu) have been widely introduced throughout the Pacific Northwest and the potential for climate-related range expansions of bass, especially into juvenile salmon rearing grounds, is of increasing conservation concern. Prior studies examining the impact of smallmouth bass on salmonids in the Pacific Northwest have l...

The movement and release of non-indigenous species (NIS) in ship ballast water is a global threat to the conservation of native aquatic species and habitats. One key to successful NIS establishment in coastal waters is propagule pressure – the size and frequency of NIS inoculations. We estimated propagule pressure of high-risk coastal zooplankton d...

Oceanographic characteristics and the presence of international shipping in Puget Sound, Washington, USA contribute to its vulnerability to non‐indigenous species (NIS) invasions. To evaluate NIS arriving in ballast water, zooplankton was sampled in 380 ballast tanks of ships after they entered Puget Sound. Taxa were classified into a higher risk g...

The potential problems of organisms introduced by ballast water are well documented. In other settings, electrolytic generation of sodium hypochlorite from sea-water has proven to be a simple and safe method of handling and injecting a biocide into water. After the hypochlorite oxidizes organisms, it reverts back to the chloride ion. Mesocosm-scale...

The potential problems of organisms introduced by ballast water are well documented. In other settings, electrolytic generation of sodium hypochlorite from seawater has proven to be a simple and safe method of handling and injecting a biocide into water. After the hypochlorite oxidizes organisms, it reverts back to the chloride ion. Mesocosm-scale...

Calanoid copepod abundance and distribution were measured by monthly plankton tows from May through November in 1998 and March through August in 1999 in three subestuaries of the Waquoit Bay estuarine system. There was a dramatic seasonal change in the composition of calanoids in Waquoit Bay with a spring community consisting of Acartia hudsonica,...

The world's ten largest rivers transport approximately 40% of the fresh water and particulate materials entering the ocean. The impact of large rivers is important on a regional/continental scale (e.g. the Mississippi drains ∼40% of the conterminous US and carries approximately 65% of all the suspended solids and dissolved solutes that enter the oc...

During the winter months (December to April), the SE United States is influenced by continental air masses from the north or northwest which pass at approximately 4 to 7 d intervals. These wind events can cause suspension of bottom sediments in Florida Bay. Over a 9 d period in March 2001, we examined the effects of a wind-mixing event on the pelag...

Some decades ago Margalef speculated that study of the exchanges across boundaries that separate different types of ecological systems would provide significant insights about properties and processes within the units that make up ecological mosaics. Although such boundaries might be difficult to define, it seemed likely that such exchanges among u...