Daniel C. Dauwalter

• PhD
• Fisheries Science Director at Trout Unlimited

Apache Trout populations are influenced by both short-term, stochastic events such as wildfire and long-term non-native species and land use impacts. Because of the need to determine the status of individual populations after stochastic events as well as assessing long-term changes periodically over time, the goals and objectives outlined in this p...

The Free Round of PBR symposium was organized to bring together students, land and fisheries managers, biologists, and restoration practitioners to review the state of science around process-based restoration (PBR). Moreover, the goal was to review contemporary information and critical knowledge gaps with respect to PBR. The full-day symposium was...

Freshwater biodiversity is declining faster than terrestrial and marine biodiversity. The protection and restoration of aquatic habitats are based, in part, on stemming this decline. We conducted a spatial conservation assessment of native fishes in the Lahontan and central Nevada basins using core-area zonation. The complementarity-based assessmen...

Objective The Southwest has the hottest and driest climate in the United States, and projections show that it will only get hotter and drier into the 2100s. The Apache Trout Oncorhynchus apache is native to the Southwest and is currently listed as threatened under the U.S. Endangered Species Act. Our goals were to understand how climate factors inf...

Nonnative Brook Trout Salvelinus fontinalis often reduce the long-term persistence of native Cutthroat Trout Oncorhynchus clarkii populations in the western United States. However, there are some instances where the 2 species have co-occurred for decades, and healthy and diverse stream habitat conditions have been suggested to facilitate sympatry....

The current extinction crisis requires effective assessment and monitoring tools. Genetic approaches are appealing given the relative ease of field sampling required to estimate genetic diversity characteristics assumed related to population size, evolutionary potential, and extinction risk, and to evaluate hybridization with non‐native species sim...

Limited resources for conservation require that conservation be strategic. Spatial conservation prioritization focuses on networks of conservation areas that efficiently maximize the representation of species. The algorithms and software underlying spatial prioritization can now account for the dendritic nature of freshwater systems. As such, spati...

Stream length is measured for many fisheries management applications. Characteristics of populations and habitats measured at field sites are commonly generalized to unsampled areas using estimates of stream length or stream network length. There are many ways to measure stream length, but map‐based stream length measurements are commonly used in f...

Ambitious intentions for expansion of the Trout Unlimited (TU) Angler Science Driftless Area Program in 2020 were greatly hampered by the COVID-19 pandemic. In 2020, the Program was intended to expand from Pierce County (WI), monitored by the TU Kiap-TU-Wish Chapter in 2019, to the other 14 TU Chapters, US Fish and Wildlife (US FWS) staff, and Minn...

Trout Unlimited applied the Conservation Portfolio framework for evaluating the status and resiliency of brook trout (Salvelinus fontinalis) populations in the Great Lakes region. The assessment consists of 4 components: 1) delineating interconnected brook trout habitat patches using trout distribution information and fish passage barrier locations...

Every year Trout Unlimited volunteers and professional staff dedicate thousands of hours and millions of dollars towards restoring coldwater habitats across the country. Projects range from small, local efforts to watershed-scale endeavors. Stream restoration, which is really about reestablishing the ecological function of degraded streams and riv...

Over the past year, MobileH2O, LLC has partnered with the Kiap-TU-Wish Chapter of Trout Unlimited (TU) on a pilot project coupling citizen science and innovative water quality monitoring technology. The intent of the project was to engage anglers to better understand the quality of coldwater resources in the Driftless Area of Wisconsin while pilot...

Trout are one of the most culturally, economically, and ecologically important taxonomic groups of freshwater fishes worldwide. Native to all continents in the Northern Hemisphere, trout belong to seven genera, which are distributed across 52 countries. Despite their broad importance as societal icons and as indicators of biodiversity, many of the...

Available: https://fisheries.org/bookstore/all-titles/afs-symposia/54091c/ This book is a valuable resource for those involved in conservation of freshwater fishes that seek proactive, integrated, holistic approaches to conservation of freshwater, riparian, and upland habitats. Many case studies from freshwater systems throughout the United State...

Efficient conservation can require making strategic decisions across large landscapes. For example, two Fish Habitat Partnerships – Desert Fish Habitat Partnership (DFHP) and Western Native Trout Initiative (WNTI) – fund conservation and restoration projects across the western United States. DFHP alone serves 11 states and nearly 180 native fish sp...

Native fish conservation areas (NFCAs) are watersheds where management emphasizes proactive conservation and restoration for long-term persistence of native fish assemblages while allowing for compatible uses. Native fish conservation areas are intended to complement traditional fisheries management approaches that are often reactive to population...

Commemorative artwork by artist Alice Best commissioned for the book, illustrating a conceptual watershed with pristine (left), restored (middle), and degraded (right) tributary streams.

Population viability analysis (PVA) is a powerful conservation tool, but it remains impractical for many species, particularly species with multiple, broadly distributed populations for which collecting suitable data can be challenging. A recently developed method of multiple‐population viability analysis (MPVA), however, addresses many limitations...

Seminar delivered to Department of Natural Resource Ecology and Management and Iowa State University, Ames, IA. Advances in spatial, temporal, and spectral resolution - in addition to data availability - has facilitated the development of new approaches to multiple population viability analysis and decision support tools to guide the next generatio...

This Special Publication of the 11th Annual Driftless Area Symposium is a review of the science conducted in the Driftless Area that is relevant to stream restoration (including habitat improvement), with each section written by scientists or restoration practitioners who have worked in the region. The review is driven by an interest in understandi...

This Special Publication of the 11th Annual Driftless Area Symposium is a review of the science conducted in the Driftless Area that is relevant to stream restoration (including habitat improvement), with each section written by scientists or restoration practitioners who have worked in the region. The review is driven by an interest in understandi...

1. The Driftless Area is expected to experience higher temperatures and more intense and frequent rainfall events as climate changes (high certainty). 2. Soil moisture is expected to decline, especially when droughts occur, but effects may be offset by increases in precipitation. 3. Trout distributions are predicted to decline with warming stream t...

Riparian and aquatic habitats support biodiversity and key environmental processes in semi-arid and arid landscapes, but stressors such as conventional livestock grazing, wildfire, and drought can degrade their condition. To enhance habitat for fish and wildlife and increase resiliency in these critical areas, land managers in the interior western...

Data used for analyses. (XLSX)

Predicted effect of beaver density on NDVI under three grazing treatments. Model selection results suggested that the most-plausible linear mixed model explaining variation in NDVI as a function of covariates included a grazing treatment x beaver density interaction term (Table 3). However, exploration of this top model revealed wide confidence int...

Overview of our Goose Creek Aquatic Assessment project completed in partnership with Idaho BLM at an Idaho BLM Aquatics Program meeting.

Population viability analysis (PVA) uses concepts from theoretical ecology to provide a powerful tool for quantitative estimates of population dynamics and extinction risks. However, conventional statistical PVA requires long‐term data from every population of interest, whereas many species of concern exist in multiple isolated populations that are...

Native Fish Conservation Areas of the southwestern USA consist of springs, ciénegas, creeks, rivers, and associated watersheds uniquely valued in preservation of freshwater fish diversity. These freshwater systems were identified through a spatial prioritization approach that identifies areas critically important to the long-term persistence of foc...

Improper riparian grazing can alter riparian vegetation and reduce streambank stability, therefore negatively impacting aquatic habitat and biota. We evaluated differences in riparian and instream habitat, benthic macroinvertebrates, and fish inside versus outside seven riparian exclosures constructed from 1982 to 2005 in Idaho, U.S.A. The Normaliz...

Many species of conservation interest exist solely or largely in isolated populations, where management priorities ideally would be guided by quantitative estimates of extinction risk. However, conventional methods of demographic population viability analysis (PVA) generally model each population separately and require temporally extensive datasets...

Freshwater fishes are threatened globally, and often too little is known about threatened species to effectively guide their conservation. Habitat complexity is linked to fish species diversity and persistence, and degraded streams often lack habitat complexity. Beaver Castor spp., in turn, have been used to restore streams and increase habitat com...

Many species of conservation interest exist solely or largely in isolated populations. Ideally, prioritization of management actions among such populations would be guided by quantitative estimates of extinction risk, but conventional methods of demographic population viability analysis (PVA) model each population separately and require temporally...

The Goose Creek subbasin in the Upper Snake River Basin has a diverse native fish assemblage that reflects the presence of rare non-game species and peripheral populations of Yellowstone cutthroat trout. This assessment examines linkages between native fishes and their habitat in the Goose Creek subbasin with several key findings: 1) fish diversity...

Apache Trout populations are influenced by both short‐term, stochastic events such as wildfire and long‐term non‐native species and land use impacts. Because of the need to determine the status of individual populations after stochastic events as well as assessing long‐term changes periodically over time, the goals and objectives outlined in this p...

Remote sensing has been pivotal to our understanding of freshwater fisheries, and we review this rapidly changing field with a focus on satellite and airborne applications. Historical applications emphasized spatial variation in the environment (e.g., watershed land use and in situ primary productivity), but improved access to imagery archives faci...

Climate change is projected to increase the frequency and severity of wildfires, warm stream temperatures, and negatively impact native trout habitat. Southwestern native trouts are often isolated from nonnative salmonids above conservation barriers and have a limited ability to recolonize after disturbances or move to track changing environmental...

Efficient conservation can require making strategic decisions across large landscapes. For example, two Fish Habitat Partnerships – Desert Fish Habitat Partnership (DFHP) and Western Native Trout Initiative – fund conservation and restoration projects across western United States. DFHP alone serves 11 states and nearly 180 native fish species. Beca...

Improper riparian grazing can alter the amount and composition of riparian vegetation and reduce streambank stability, which in turn can result in wide and shallow stream channels with poor habitat for aquatic biota. Riparian exclosures are one grazing management tool used to reduce livestock access to streams and improve stream health. We evaluate...

Habitat diversity reflects the range of available habitats used by species with different niche requirements and, therefore, influences species diversity. Land use influences stream condition, and streams in poor condition are often wide, shallow, sediment-laden channels with low instream habitat diversity. Our goal was to evaluate the effect of in...

Regional climate, geology, vegetation, and land use influence hydrogeomorphic processes, which influence stream channel form and the recruitment and transport of wood in streams. We studied relationships between channel morphology and frequencies of large in-channel wood in three upland ecoregions of eastern Oklahoma where streams contain high fish...

Freshwater fishes living in streams and rivers can be affected strongly by isolation, which causes a disproportionate degree of fragmentation in such dendritic systems. Isolation disrupts important ecological and migratory processes as well as the ability to access refuge habitats during disturbances. The restoration of habitat connectivity, then,...

Models suggest changes in climate and precipitation for Wisconsin and the upper Midwest will impact stream discharge. Of particular concern is that increased high flows will lead to disasters affecting local economies, elicit mental health problems, increase stress disorders, and impact recreational and drinking water. In order to better understand...

Trout Unlimited (TU) was founded in 1959 on the banks of the Au Sable River in Michigan, USA. The 16 fisherman that initially met at the home of George Griffith were bonded by their love for fishing and growing discontent with the management of some streams. They simply thought that Michigan’s trout streams could produce far superior fish if the h...

Remote sensing products, including aerial imagery, can be used to quantify characteristics of watersheds and stream corridors that often predict the distribution and abundance of aquatic species. We conducted a supervised, object-oriented classification of imagery from the National Agricultural Imagery Program to develop a high-resolution (1-m) lan...

Executive Summary The US Bureau of Land Management (BLM) manages a substantial portion of public lands in the western United States. Many of these public lands contain significant biological and cultural resources that span not only BLM lands but private, tribal, state, and other federal lands as well. Thus, multiple-use land management (mining, gr...

Brook Trout Salvelinus fontinalis in New England coastal streams can exhibit partial anadromy, but the status of Brook Trout and anadromous behavior is unknown for much of the region. We conducted a sub-watershed-scale (~12,000 ha) assessment of coastal and anadromous Brook Trout from Maine to Long Island, New York using data from regional fisherie...

Key Points: • Fisheries education and the fisheries employment arena are changing. • Fisheries students should seek a core in both the natural and social sciences, and acquire field, laboratory, and communication skills. • Students need to be persistent in tailoring their degree program and experiences to position themselves for the job they want.

Impacts from grazing, agriculture, and other anthropogenic land uses can decrease stream habitat complexity that is important to stream biota and often is the goal of stream habitat restoration. We evaluated how microhabitat complexity structured a fish assemblage and influenced habitat selection by the Northern Leatherside Chub (Lepidomeda copei),...

Brook trout Salvelinus fontinalis in New England coastal streams can exhibit partial anadromy, but the status of brook trout and anadromous behavior is unknown for much of the region. We conducted a subwatershed-scale (~12,000 ha) assessment of coastal and anadromous brook trout from Maine to Long Island, New York using data from regional fisheries...

Brook trout in New England coastal streams can exhibit partial anadromy. However, anadromous brook trout, often called “salters,” have declined and their current status in New England is uncertain. We conducted a rangewide assessment of coastal and anadromous brook trout from Maine to Long Island, New York. Across 471 streams, brook trout are thoug...

Native Fish Conservation Areas (NFCAs) are watersheds where management emphasizes proactive conservation and restoration for long-term persistence of native fish assemblages while allowing for compatible uses. NFCAs are intended to complement traditional fisheries management that can be reactive to existing stressors and focused on single fish spec...

Energy development threatens fish and wildlife resources worldwide. This study used constrained ordinations to show fish assemblage structure associated with oil and gas well densities in the Colorado River Basin, Wyoming, but well densities explained only 6.4% of assemblage structure when compared to other factors. Threshold Indicator Taxonomic AN...

Forecasts of species distributions under future climates are inherently uncertain, but there have been few attempts to describe this uncertainty comprehensively in a probabilistic manner. We developed a Monte Carlo approach that accounts for uncertainty within generalized linear regression models (parameter uncertainty and residual error), uncertai...

Climate change is projected to increase stream temperatures, alter flow regimes, and adversely affect native trout distributions. In addition to improving contemporary habitat conditions, many stream restoration practices - such as restoring riparian vegetation, habitat diversity, or environmental flows - also have the potential to offset climate c...

Trout Unlimited (TU) developed the Conservation Success Index (CSI) as a science-based tool to help guide conservation decisions of organizational staff, volunteers, and partners. The CSI is a spatially-explicit, composite index based on four different groups of indicators used to describe the status of native salmonids: rangewide conditions, popul...

Streams and rivers along the Atlantic Coast have been impacted by human activities such as dam building, water quality impairment, and sedimentation for centuries. As a result, the suite of diadromous fish species that use them for spawning and rearing habitat, and that require access to the ocean, have declined in distribution and abundance. We us...

Broad-scale studies of climate change effects on freshwater species to date have focused mainly on temperature, ignoring critical drivers such as flow regime and biotic interactions. We used downscaled outputs from general circulation models coupled with a hydrologic model to forecast the effects of altered flows, biotic interactions, and increased...

Since 2006, with the advent of the National Fish Habitat Action Plan, there has been a concerted effort to address western fish habitats by numerous recognized National Fish Habitat Partnerships. The Western Native Trout Initiative, the Desert Fish Habitat Partnership, the California Fish Passage Forum, the Reservoir Fisheries Habitat Partnership,...

Broad-scale studies of climate change effects on freshwater species have focused mainly on temperature, ignoring critical drivers such as flow regime and biotic interactions. We use downscaled outputs from general circulation models coupled with a hydrologic model to forecast the effects of altered flows and increased temperatures on four interacti...

Freshwater fishes continue to decline at a rapid rate despite substantial conservation efforts. Native fish conservation areas (NFCAs) are a management approach emphasizing persistent native fish communities and healthy watersheds while simultaneously allowing for compatible human uses. We identified potential NFCAs in the Upper Colorado River Basi...

The upper Colorado River basin contains one of the most imperiled fish faunas in North America. Anthropogenic land use and nonnative species impacts are considered among the top reasons for imperilment. We determined the association of anthropogenic land use intensity (road density, percentage of converted land, and oil and gas well density), relat...

The fluvial system represents a nested hierarchy that reflects the relationship among different spatial and temporal scales. Within the hierarchy, larger scale variables influence the characteristics of the next lower nested scale. Ecoregions represent one of the largest scales in the fluvial hierarchy and are defined by recurring patterns of geolo...

Managers are often required to monitor networks of sites to make inferences about trends in fish populations over large geographic areas. We evaluated the statistical power of four revisit monitoring designs (always revisit design; two types of augmented serially alternating design; and serially alternating design) to detect declines in trout popul...

Broad-scale variables (i.e., geology, topography, climate, land use, vegetation, and soils) influence channel morphology. How and to what extent the longitudinal pattern of channel morphology is influenced by broad-scale variables is important to fluvial geomorphologists and stream ecologists. In the last couple of decades, there has been an increa...

Peripheral populations—generally defined as those at the geographic edge of the range—often have increased conservation value due to their potential to maximize within-species biodiversity, retain important evolutionary legacies, and provide the fodder for future adaptation. However, there has been little exploration of their conservation value in...

Broad-scale variables (i.e., geology, topography, climate, land use, vegetation, and soils) influence channel morphology. How and to what extent the longitudinal pattern of channel morphology is influenced by broad-scale variables is important to fluvial geomorphologists and stream ecologists. In the last couple of decades, there has been an increa...

Global positioning systems (GPS) are increasingly being used for habitat mapping because they provide spatially referenced data that can be used to characterize habitat structure across the landscape and document habitat change over time. We evaluated the accuracy of using a GPS for determining the size and location of habitat patches in a riverine...

Many native fishes in the Upper Colorado River Basin are in decline. The endangered large-river fishes and Colorado River cutthroat trout have received the most attention, but recent efforts have focused on three declining warmwater species – flannelmouth sucker, bluehead sucker, and roundtail chub. The National Fish and Wildlife Foundation adopted...

Freshwater species are among the most imperiled in North America. Desert aquatic habitats in the American West support half of freshwater fish species listed under the Endangered Species Act. Although individual states have Wildlife Action Plans listing species and habitat conservation priorities within their borders, only recently has a comprehens...

The electrofishing distance needed to estimate fish species richness at the stream or river reach scale is an important question in fisheries science. This distance is governed by the shape of the species accumulation curve, which, in turn, is influenced by a combination of factors, including the number of species, their overall abundances, habitat...