Wetland Focal Strategies
Abstract: The Intermountain West Joint Venture (IWJV) is the largest and most ecologically diverse of the U.S. Habitat Joint Ventures and provides habitat for birds across all major annual cycle events. Due to the immense scale of conservation needs in the Intermountain West it is essential that limited resources be allocated strategically in ways that maximize the integrity of priority landscapes. Thus, the IWJV has embraced a strategic framework to guide planning efforts and achieve long-term avian conservation goals in the Intermountain West. This document is identifies how IWJV science resources and planning activities will be prioritized over the next 5 years (2013–2018).
The conservation of wetland habitats has been a focus of the IWJV since its inception and wetlands were identified as a high priority for enhanced conservation planning (see Habitat Prioritizaton). Wetlands are widely dispersed across the Intermountain West and characterized by high biological diversity and productivity which make them among the most important wildlife habitats in the Intermountain West. Over 80% of wildlife species common to the region depend on wetlands to meet some part of their annual cycle needs though they encompass a small footprint in the Intermountain West. Wetlands also provide a variety of ecological goods and services and are important components of ranching and agricultural economies in the Intermountain West. However, most wetland systems in the Intermountain West have been impacted by anthropogenic factors due to their high biological productivity and association with water resources in a predominately xeric landscape.
Despite the significance of wetland resources to society and wildlife in the Intermountain West, especially migratory birds, significant information gaps remain regarding inventories to adequately assess regional distribution and trends of wetland resources. Consequently, we are challenged to measure or understand the cumulative impacts of wetland loss or conservation at landscape scales. Additional science investments are required to develop the information which will inform effective conservation strategies for wetland resources in the Intermountain West that are linked to continental and regional avian objectives.
A two-phase approach was used to identify priority strategies for further IWJV wetland science and planning.
- Phase-I involved a number of data summaries and analyses to evaluate wetland abundance, distribution, and land ownership patterns across the region. Digital NWI data was used to summarize wetland density by measuring wetland abundance within an array of 16 km² grid cells across the IWJV. This identified a clear pattern of wetland clustering across the region and indicated approximately 87% of wetland abundance across the Intermountain West occurs in only 10% of the landscape area. An evaluation of surface ownership across the IWJV indicated only 30% of surface ownership is privately owned yet 70% of emergent wetland resources in the region occur on privately owned lands. Wetland resources on private lands are likely more susceptible to environmental threats than those that occur on public lands. Thus, the potential impact to wetlands is substantial when considering issues of current and projected water supply and demand across the West. An evaluation of broad-scale anthropogenic impacts indicated human settlement patterns in the Intermountain West has disproportionately affected wetland dominated landscapes which are commensurate with areas of high biological productivity and biodiversity. The results of these summaries were used as data inputs to complete conceptual landscape prioritization models in Phase-II.
- In Phase-II, an evaluation of wetland clustering patterns and supporting documentation of important wetland areas identified a suite of 18 wetland landscapes that aligned with landscapes identified in prior IWJV and existing partner planning documents. These 18 wetlands landscapes alone encompass approximately 50% of wetland abundance in the Intermountain West. We used a modeling approach consistent with Structured Decision Making to evaluate relative landscape value via a suite of avian species with high population reliance (i.e., strong continental scale linkage) on Intermountain West habitats and landscapes and that represented the diversity of wetland and aquatic habitats within the IWJV. Landscape values were assessed by individual species dependence and utilization during major annual cycle events (breeding, migration, winter).
Evaluation of model scores identified two landscapes with distinctly high values, the Great Salt Lake (GSL) and Southern Oregon-Northeast California (SONEC). These two landscapes alone comprised 49% of the wetland area among the 18 landscapes and approximately 25% of overall wetland abundance in the IWJV occurs in GSL and SONEC landscapes. These two landscapes should be considered high priority for science-based planning and conservation by the IWJV in both near and long-term planning horizons. However, not all species may be equally served by focusing on two ecoregions. Thus, a landscape species approach to conservation planning was identified as a suitable alternative planning framework.
The use of landscape species confers an important umbrella role in securing the habitat conservation needs of many other species, species assemblages, and larger-scale ecological processes. To identify an appropriate landscape species, a set of variables were developed which sought to characterize, across a suite of species, their geopolitical connectivity, relevance to conservation partners, population dependence within the Intermountain West, and degree of population/habitat information available for planning efforts.
This evaluation identified Sandhill Cranes as a suitable landscape species to serve as a vehicle for wetland conservation in the Intermountain West. Among those species evaluated, Sandhill Cranes had the broadest connectivity to partners across the Intermountain West, had high population reliance on Intermountain West landscapes, exhibited strong relationships to wetland habitats amenable to existing conservation programs, and possessed sufficient population-habitat data to inform planning models.
Conservation science investments in SONEC, Great Salt Lake, and Greater Sandhill Crane strategies are anticipated to yield high conservation returns at multiple scales. These priorities define the geographic and contextual scope of science-based conservation investments the IWJV will facilitate over the next 5 years. However, these priority strategies do not identify more detailed habitat objectives or information needs.
Development of more detailed conservation objectives within SONEC, Great Salt Lake, and Greater Sandhill Crane strategies will require engagement of regional, local, and issue-based stakeholders. These steps will help ensure conservation actions that occur at local levels have relevant conservation impacts (i.e., support population goals and habitat objectives) at regional and continental scales. Working groups for each strategy will be developed to guide and inform habitat conservation strategies.
Executive Summary of IWJV Technical Plans: