Hagen Lab

Sage-Grouse Mega-Wildfire & Juniper Removal

Evaluating population response and dynamics related to disturbance and management

In the summer of 2012, wildfires burned more than 475,000 ha of sagebrush habitat in southeastern Oregon and northeastern Nevada. The Holloway fire alone burned > 186,000 ha, including the entire Trout Creek Mountain sage-grouse core area which hosted one of the densest sage-grouse populations in Oregon. While the effects of wildfire on sage-grouse populations have been studied for small wildfires, generally multiple years after the fire, or on prescribed burns, there is currently no information on the short-term (acute) response of sage-grouse populations to large scale wildfire (>100,000 ha).

Two months post-fire Oregon Department of Fish and Wildlife began to evaluate the effects of the Holloway fire on local sage-grouse populations.  They initiated a pilot study, placing VHF radio-transmitters on 20 sage-grouse captured in Oregon within the Holloway fire boundary in October 2012.  The pilot project evolved (in collaboration with Co-PI, Katie Dugger) into marking female sage-grouse (~30 per year) with GPS-PTT transmitters to examine demographic rates, movements and space use in a post catastrophic wildfire landscape. We marked >236 females since then resulting in >250,000 locations.

In 2009, we began a Before-After Control-Impact (BACI) study where ~10,000 ha of early encroaching trees were to be removed on BLM and private lands in the Warner Mountains.   Initially, we used VHF transmitters, annually marking ~40 female grouse in each the treatment and control areas, we transitioned to GPS-Transmitters in 2015.  The patterns of avoidance to existing encroachment is evident, we are anxiously awaiting the results of bird response to tree removal. We marked >793 females since then resulting in >500,000 locations.

Both of these studies collected data for 10 years or more. We aim to use these extensive and contemporaneous datasets to disentangle questions about population dynamics as they relate to large scale disturbance and conservation actions. We will be using integrated population models to evaluate how grouse respond to these changes.

Population Bottleneck in Central Oregon’s Declining Sage-Grouse Population

What are the limiting factors?

Greater sage-grouse have experienced population declines due to loss and fragmentation of habitat. In the Great Basin the primary driver has been conifer encroachment. Little research has been conducted to specifically evaluate the effect. Western juniper distribution in the Great Basin has increased ~10-fold since pre-European settlement, but, although juniper management is becoming more widespread, there is a paucity of data regarding how juniper encroachment and management may actually affect sage-grouse. One of the key stressors for sage-grouse in the Great Basin is conversion of sagebrush habitat to annual grasses.  Southeast Oregon is part of one of the largest contiguous sage-brush steppe habitats remaining within the extant range of greater sage-grouse. 

Understanding mechanisms influencing sage-grouse habitat use and demographic rates related to large scale habitat loss and fragmentation, including pinyon–juniper and invasive annual grasses, is essential to ensure long-term effective restoration success.

This project is intended to be carried out hierarchically by: 1) quantifying sage-grouse population-level responses at local and landscape scales 2) identifying population bottlenecks in declining and stable populations, and 3) measuring responses of individual birds to juniper removal and annual grass invasion. Recent rangewide analyses indicated that in Oregon Brothers Priority Area of Conservation has been in decline and warrants further assessment and management actions.  Alternatively, the Paulina PAC, which is adjacent to Brothers has remained stable.  Both of these PACs are managed by Prineville District of the Bureau of Land Management. While each PAC faces slightly different threats, both juniper encroachment and invasive annual grasses are threats held in common.

Maintaining Resilient Sagebrush & Rural Communities

A west-wide evaluation of factors effecting grouse and rural communities that they cohabitate

Resilience in social-environmental systems (SES) is “the capacity to tolerate, absorb, cope with, and adjust to changing social or environmental conditions.” The intrinsic linkages between people and nature necessitate that resilience of either human or ecological communities is affected by the resilience of the other. Because humans and nature are deeply intertwined and cannot be disentangled, holistic investigations focused on complex interactions between people and nature offer the greatest opportunity to address these problems and advance human knowledge about SES. Responding to this challenge, our team will conduct a transdisciplinary study of socioeconomic and ecological resilience in the sagebrush (Artemisia spp.) biome, one of the largest SESs in the U.S. and contains some of our nation’s fastest growing human population centers. Our study will 1) identify thresholds for transformative changes in human and ecological communities; and 2) elucidate options for fortifying socioeconomic resilience to help rural communities thrive in the new rural West, where socioeconomics are less-dominated by livestock ranching as energy and exurban development accelerates.

This project is perhaps one of our most exciting collaborations as a transdisciplinary NIFA project: Maintaining Resilient Sagebrush Systems and Rural Communities. This team includes sociologists, micro- and macroeconomists, and both field and quantitative ecologists from 9 land grant institutions (including OSU) from across the West. The broad scale goal is to enhance our understanding as to how land management for imperiled species affects rural communities (i.e., socially, economically, and environmentally), and how actions of the community affects those species. By leveraging existing empirical field studies across the distribution of sage-grouse, and combining it with new socio-economic surveys we have the potential to unravel the complex story as to how best to manage ecosystems for imperiled species.

Lower Klamath & Tule Lake National Wildlife Refuge

 Permanent emergent wetlands and breeding waterbird communities

At its peak, the Klamath Basin was considered to be the heart of the Pacific Flyway for breeding and migratory waterfowl habitat. Since then, substantial changes to the landscape have occurred due to water management decisions, drought and agricultural expansion. Tule Lake and Lower Klamath National Wildlife Refuge must base their annual habitat management decisions on water availability. Unfortunately, these wetlands are typically looked at as a water loss through evapotranspiration and their larger ecological value has not been considered in local water management decisions. These decisions have led to both Tule Lake and Lower Klamath drying completely for the first time since their creation. Although these circumstances are unfortunate, there is a unique opportunity at hand to assess the seed bank and vegetation viability in response to prolonged drought. 

Our research is focused on understanding the effects of prolonged drought on wetland plant seeds and root systems. Specifically, we are assessing the viability of submerged aquatic plant seeds and emergent plant rhizomes in response to drought severity, to estimate response when water returns to the system. As both emergent and submerged aquatic plants are essential for a productive wetland, it is important to know how these plants are affected by extended periods of drought. Findings from this research will be beneficial to all permanent and semi-permanent wetlands and wetland managers working in the face of climate change.

Determining Yellow Rail Distribution and Abundance

 A secretive marsh bird is “a canary in the coal mine” of emergent wetland health

Yellow Rails are a species of conservation concern because of their specialized habitat needs within shallow wetland systems.  In particular, the core of the western Yellow Rail population resides in Klamath Marsh NWR and its persistence is reliant on perennial wetland conditions.  Little is known about western Yellow Rail ecology and distribution outside of the Klamath Marsh and a few surrounding wetlands. Importantly, Yellow Rail depend on wetland habitats associated with flooded riparian and perennial wet meadow systems. The species share this habitat with other wetland dependent species of concern including the Oregon Spotted Frog and Sandhill Crane (and in some places including Klamath Marsh and the Wood River Valley overlap with redband trout, and several species of endemic lamprey. These wetland systems are not only critical to the persistence of these species they provide essential ecosystem services that drive watershed nutrient and water budgets.  The population trend of Yellow Rail and other wetland dependent species is a critical metric for the overall health and well-being of the larger watershed.

To reduce the uncertainty regarding the species distribution, metapopulation trends/dynamics, and about the species conservation future, considerable work is needed to survey similar wetland habitats across a broader landscape to determine site occupancy and abundance. Such efforts will create a reference point and accurate distribution map from which to begin to understand how global stressors may be affecting Yellow Rail and its habitat in western North America. Our goals are three-fold: 1) develop a regional map of shallow wetland systems upon which Yellow Rail depend, 2) design a survey methodology using Automated Recording Units that could be deployed across a broader region, and 3) from those surveys and shallow-wetland map develop a regional Yellow Rail occupancy model that would inform a species distribution map.

Reducing Avian x Wind Turbine Collision with Strokes of a Brush

Measuring the effectiveness of painted rotor blades in reducing avian collision

Since the emergence of utility-scale wind energy production, efforts to reduce collision risk between flying animals and turbines have been challenged by the biological and technological complexities. Birds and bats vary widely in their habits and flight behavior, and animal monitoring and identification systems designed to detect and curtail such impacts are complex, expensive, require ongoing maintenance, and may interfere with energy production. Nonetheless, federal and state regulatory agencies are mandated to respond to legal protections for flying animals (e.g., Endangered Species Act, Migratory Bird Treaty Act, Bald and Golden Eagle Protection Act). This challenge is compounded by forecasted growth in terrestrial and offshore wind energy production of 435% between 2020 and 2050, which, in turn, will increase hazards posed to birds from both the increase in the number and size of turbines. There is a growing need to identify ways for birds and bats to safely coexist with cost effective wind energy production.

Our first objective will determine whether there is an effect on mortality rate of eagles (bald and golden) from painting turbine blades. Second, we aim to determine if there is an effect on mortality rates of flying animals that are not eagles (all bats, all other bird species). This second objective is essential to ensuring that blade painting does not somehow increase non-eagle mortality even as it may reduce eagle mortality. Understanding potential impacts to non-eagle birds and bats will be important as regulatory agencies will desire information on impacts to the broad suite of species that may be susceptible to turbine-related collisions.

“Dead Birds Flying”-the Role of Rehabilitated Raptors in Conservation and Mitigation

Evaluating the plausibility of rehabilitated raptors replacing individuals lost to industry take

A growing body of evidence suggests that current rates of human-caused golden eagle mortality may be unsustainable. Best available science indicates the sources of eagle mortality are unusually diverse, including car strikes, wind turbine strikes, electrocution, lead poisoning due to ingestion of shot carcasses, shooting, nest site disturbance and more.

These trends have prompted the USFWS to adopt a rule of ‘‘net benefit, or at minimum, no net loss’’ within the Eagle Conservation Plan Guidance Module for land-based wind energy. The provisions within this rule require any permitted eagle take must be mitigated by the permit holder with a quantifiable conservation action that minimizes impacts or compensates for take. Recent analyses suggest golden eagle take should remain below 5% to maintain population stability. Permit holders face challenges complying with the rule due to the lack of options. Currently, the USFWS provides only one compensatory option – power pole protection retrofits. Formalizing a suite of mitigation alternatives may assist in meeting the offset requirements within a specific project or region.

Our goal is to assess the plausibility of using rehabilitated birds of prey as a mitigation offset for birds killed via electricity generated from wind energy facilities or other industry sectors. Our objectives are 1) to provide rigorous survival estimates for birds of prey that are frequent admissions to raptor rehab facilities across North America, 2) assemble productivity estimates from extensive literature review, and 3) develop models that project the contribution of rehabbed individuals to offset take as it relates to energy infrastructure.

Trees, cows and drought, oh my!

Developing science to guide lesser prairie chicken conservation.

My previous role as Science Advisor to the US Department of Agriculture, Natural Resources Conservation Service’s Lesser Prairie-Chicken Initiative (LPCI) lead to a number of research projects some of which are still being finalized and written up. In this capacity I had two primary directives 1) to develop spatially explicit decision support tools to guide where and when conservation activities should occur, and 2) collaborate with independent researchers to evaluate the outcomes of these broad-scale conservation actions.  In a nutshell, it was a 3-tiered monitoring scheme: I) fine-scaled highly detailed bird work “petri-dish studies,” measuring bird response to specific management prescriptions (e.g., grazing management, tree removal); II) mid-scale using GIS and spatial modelling to evaluate regional outcomes; and III) using hierarchical occupancy modelling to assess distributional shifts of birds as a function of habitat and conservation actions range-wide.

Since 2012, science-based tools have been implemented to target the removal of invasive eastern redcedar, invasive honey mesquite, and identifying native prairie and CRP landscapes at greatest risk of conversion to tillage agriculture for short- and long-term easements. These tools were developed at a regional scale (tier-II) such that the extent and potential cost of each threat could be quantified. As we begin to wind down our monitoring efforts, a meta-analysis of the demography of prairie-chickens has been completed. A collaboration with Colorado State University, Kansas State University, Oklahoma State University, New Mexico State University, Texas Tech, and the 5 state wildlife agencies has resulted in a range-wide Integrated Population Model that synthesizes lek count data and detailed demographic data collected from field studies on radio-telemetered birds. A first of its kind!