Much of our work focuses on the biology and ecology of wildlife species associated with late successional forests in the Pacific Northwest, particularly interactions between forest-adapted predators and their prey.  A few of our projects are highlighted below.

Northern spotted owl studies

Long-term Spotted Owl Research
We study long-term population dynamics on 5 study areas in Oregon and Washington. Population monitoring documents survival, reproductive success, and annual rate of population change.

​Spotted Owl Resource Selection
We have several completed and ongoing projects to understand how owls use forests in relation to a variety of abiotic and biotic factors.  
​
Effect of Barred Owls and Wildfire
We are working to understand how wildfire and competitive interactions with barred owls affect the conservation of the northern spotted owl.

bioacoustics of pacific northwest forests

The U.S. Forest Service and other partners have monitored northern spotted owl demography in the Pacific Northwest since the early 1990s under the Northwest Forest Plan. As part of this long-term research crews broadcast recorded owl calls to elicit a response from real owls; those birds are then marked and resighted at historical territories. As spotted owl populations have declined due to habitat loss and competition from invasive barred owls, this technique has become less and less reliable. Since 2017 we have been conducting passive bioacoustics research to develop an alternative approach to monitor spotted owls and better understand avian community dynamics in Pacific Northwest Forests.

red tree vole ecology

Red tree voles (Arborimus longicaudus) are a highly specialized arboreal rodent endemic to western Oregon and northwest California. They are most abundant in old coniferous forest (>80 years old) and are associated with forest characteristics consisting of a mixture of large trees and uneven-sized trees suggesting complex branch and bole structure are important to their persistence. Despite this association with old forests, tree voles and their sign are commonly found in young forests; albeit often at low density and occupancy may be quite ephemeral. Old forest conditions are likely required for tree vole persistence, but young forest may function as habitat or as connecting matrix between tree vole populations occurring in old forest patches. We have several project to better understand what conditions in some young forests may facilitate occupancy, and underlying factors that may limit wide spread distribution in young forests. ​

Long-term Small mammal population dynamics

We are conducting a long-term study of small mammals in late-successional forests of the H.J. Andrews Experimental Forest. The importance of understanding relationships between forest-adapted predators (including northern spotted owls) and their prey has been repeatedly acknowledged in scientific literature. We know that prey communities can affect population performance and space use of predators, but few studies have been conducted to better understand those interactions. This study is designed to quantify annual variation in abundance of several small mammal species and provide information about the linkage between population performance of predators and those small mammal populations. 

Food Web dynamics in an old-growth forest

Picture
Western spotted skunk
Picture
Gray fox
Terrestrial food webs are relatively understudied in the Pacific Northwest, and a better understanding of the structure and dynamics among multiple trophic levels in these ecosystems can improve conservation and forest management. The HJ Andrews Experimental Forest is a National Science Foundation Long Term Ecological Research site with over 60 years of research on the forests, streams, and watersheds. The terrestrial food web and particularly the mammal community have not received as much research as other components of the ecosystem. Small carnivores play an important role in the functioning of Pacific Northwest forests, so Marie Tosa is investigating the interactions between small carnivores and their small mammal prey in a food webs approach focused on diet and energy flows. She is integrating carnivore and small mammal data with various other long-term data to better understand the HJ Andrews terrestrial food web. Follow Marie's blog about her adventures in this research: Skunk Tales​ 

camera trap malawi

Picture
African buffalo
As part of its mission to restore ecological function of Nkhotakota Wildlife Reserve (NWR), African Parks Malawi (APM) translocated 486 African elephants (Loxodonta africana), 100 greater kudu (Tragelaphus strepsiceros strepsiceros), 193 African buffalo (Syncerus caffer), 200 sable antelope (Hippotragus niger), 505 waterbuck (Kobus ellipsiprymnus), 25 eland (Taurotragus oryx), 25 zebra (Equus quagga), 122 impala (Aepyceros melampus), and 199 warthog (Phacochoerus africanus). These animals were translocated from other protected areas in Malawi (Majete Wildlife Reserve and Liwonde National Park) in 2016 and 2017. More translocations are being considered in the coming years, including large predators such as African lion (Panthera leo). Translocated animals were initially confined to a 19,000 ha sanctuary within NWR and after completion of the second stage of perimeter fencing in 2017 they were given access to 78,000 ha. APM anticipates that with completion of the full perimeter fence in 2018, and removal of all interior fencing, wildlife will have full access to the entire reserve. We have designed and are deploying camera traps throughout the reserve to inventory and monitor wildlife populations. ​
More information coming soon!
Lesmeister Predator-Prey Lab
USDA Forest Service, Pacific Northwest Research Station
Corvallis Forestry Sciences Laboratory
Oregon State University
3200 SW Jefferson Way
Corvallis, OR 97330
​541-750-7250