Sage-Grouse and Catastrophic Wildfire: Try and rebuild or find a new home?
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.
Now heading into year eight, patterns are starting to emerge. A strongly philopatric and long-lived species such as the sage-grouse can be slow to adapt, and are attempting to “rebuild” rather than find a new home. The lack of plasticity in responding to the fire has a fitness cost in terms of reproductive success and markedly reduced adult survival, resulting in reductions in population growth. Linking these demographics to space use is our next challenge in attempting to unravel how we might improve restoration efforts post-fire to benefit grouse.
Warner Mountains Juniper Removal: Are there biological benefits to sage-grouse?
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. Our goal is to assess specific effects of juniper encroachment and management on demographics and space use at multiple spatial scales.
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. The patterns of avoidance to existing encroachment is evident, we are anxiously awaiting the results of bird response to tree removal-stay tuned!
In this final phase of the BACI (2015-21) we have transitioned to GPS-PTT transmitters to acquire finer resolution movement and space use data. Again linking demography to space use: we have found both increases in usable space and improved demographic performance as it relates to the removal of juniper. This information will be vital in determining how conifer encroachment effects sage-grouse populations as well as informing management actions aimed at ecosystem restoration. More recently, we have begun to examine thermal aspects of brood use, brood survival as it pertains to juniper cover and removal. Additionally, we are examining how herbaceous forage quality and quantity is affected by these sage-grouse specific treatments, and changes in invertebrate communities. This project is a broad partnership including Lakeview Distict BLM, Cedarville BLM, NDOW, ODFW, University of Idaho, USDA-Natural Resources Conservation Service, Intermountain West Joint Venture, and Pheasants Forever.
Clear Lake National Wildlife Refuge: bringing sage-grouse back from the brink.
Clear Lake National Wildlife Refuge is a large reservoir in the middle of the high desert, surrounded by Modoc National Forest. Along with supporting a nesting colony of white pelicans, the surrounding uplands supports a small population of sage grouse. What was once a thriving population with 56 leks, now only supports 1 lek on Clear Lake NWR, whose numbers were as low as 5 males in attendance in 2005. Clear Lake NWR and Modoc NF have been greatly affected juniper encroachment, wildfire, and invasive grasses. Local landowners and federal and state agencies formed a working group to recover this population and its habitat through translocation, juniper removal, and most recently herbicide spraying for invasive grasses. From 2007-2011, the USFWS and Humbolt State University conducted a study on nest and adult female survival, and found these rates to be comparable to other populations in nearby states. However, lek numbers continue to fluctuate, and no new leks have been discovered since translocations began in 2005.
In 2019, we began a study to estimate demographic rates of the Clear Lake population and continue translocation. Adult females were translocated from Nevada in March, and resident birds were also captured on Clear Lake. However translocated females had low survival, and both groups had low nest success. Raven populations and invasive grass cover had also increased since the previous study. The research focus was shifted to resident birds and translocations were temporarily halted as a result of concerns raised regarding depressed vital rates. Current research efforts are focused on identifying limiting factors and bottlenecks in the annual life-cycle. Additionally, we are characterizing the predator community and evaluating mammal and avian probability of use through 70 camera traps and distance sampling surveys deployed throughout the study site.
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 and agricultural expansion. The loss of seasonal wetlands has had significant negative impacts on numerous waterbird populations over the last several decades. 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.
There has been little formal research conducted in this area that determines the value of these wetlands as they pertain to waterbird reproduction. In 1952, a study by California Department of Fish and Wildlife was conducted to acquire preliminary data on the activity and habitat requirements of nesting waterfowl in the Klamath Basin. Since this study, there has not been another like it on this Refuge complex, and with increasing demands on water use more information is needed on the importance of these resources for waterbird communities.
Our research is focused on understanding the importance of permanent emergent wetlands in the Klamath Basin as it pertains to waterbird reproduction and endangered fish populations. We will do this by characterizing wetland composition and waterbird communities present, the nesting activity by species, and hydrological changes. These categories will provide crucial data that can be compared to historical records in order to show the ecological value wetlands in the Klamath Basin hold for wildlife and waterbird species. Results from this research will allow for management decisions to be made in wetlands across the Pacific Flyway.
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. Several Master’s projects have been completed at Kansas State University (https://www.k-state.edu/kscfwru/Haukos/Students.html) that specifically address the effectiveness of LPCI practices to benefiting Lesser Prairie-Chicken ecology. University level field research continues to address the effects of livestock grazing, and tree removal on LEPCs, and additional work has been completed or ongoing at Oklahoma State University, Texas Tech University (http://integratedclimatettunrm.blogspot.com/p/current-projects-and-co.html), and New Mexico State University (http://web.nmsu.edu/~carleton/Scott_Carleton/Research.html).