Inventory & Monitoring Partnerships Aim to Improve Park Forest Health from Coast to Coast

A whitebark pine monitoring team counts pinecones at Yellowstone National Park.

NPS / Jacob W. Frank

Introduction

Across the National Park System, the National Park Service’s Inventory and Monitoring (I&M) Division is helping park managers improve the health and function of forest ecosystems. In the Northeast, the Resilient Forests Initiative is providing park staff with the tools and connections necessary to address regionwide threats to forests. In the West, multiple networks are collaborating across agency lines for conservation of whitebark pine. And in Hawaiʻi, innovative efforts to protect forest birds from avian malaria are showing promising results. These partnerships are helping parks exchange information, leverage funding sources, and collectively administer actions to deliver cross-scale scientific outcomes. All three projects are now set to enhance their scope of impact with funding from the US Bipartisan Infrastructure Law and Inflation Reduction Act.

Resilient Forests Initiative

Stony Man Trail at Shenandoah National Park in the Mid-Atlantic Network, a participant in the Resilient Forests Initiative.

NPS / D. Ippilito

In November 2022, 120 National Park Service (NPS) biologists, invasive plant management teams, regional leaders, I&M network staff, partners, and collaborators came together to learn about and address major challenges to northeastern forests. Over three days, participants discussed changing climate, overabundant deer, novel pests and pathogens, invasive plants, and altered disturbance regimes. Since then, staff from five I&M networks (Eastern Rivers and Mountains, Northeast Temperate, Mid-Atlantic, National Capital, and Northeast Coastal and Barrier) have engaged in collaborative partnerships with parks, supporting programs, and external organizations to address a wide variety of threats affecting the function and diversity of eastern forests.

A recent analysis of 12 years of monitoring data on forest regeneration found that forests in 27 of 39 (69%) eastern parks were in imminent or probable danger of regeneration failure. A range of interacting stressors, especially over-abundant white-tailed deer, invasive plants, and insect pests, are reducing forest sustainability. Many parks lack the seedlings and saplings needed to replace canopy trees as they die, and increasingly abundant non-native plants further suppress tree regeneration. A manuscript documenting the work was published in the journal Ecological Applications. Park-specific resource briefs highlighting the research findings are also available from the Schoodic Institute.

Biologists from the National Capital Region Network collect data about new growth by measuring the girth of trees and saplings, and counting seedlings.

NPS / Claire Hassler

That analysis, and its resultant publications, are just the beginning of the collaborative I&M effort to help more than 25 parks sustain their forests. In 2024, a follow-up virtual workshop again brought park staff together to share resources and strategies for sustainable forest management. The Resilient Forests Initiative and trainings laid the groundwork for multiple successful proposals for Bipartisan Infrastructure Law (BIL) and Inflation Reduction Act (IRA) funding to address climate change and other impacts to forests. Projects include restoration focusing on invasive shrub removal, planting of climate- and pest-adapted native trees, deer management, promoting oak regeneration, protecting forests in historic battlefield and cultural landscapes, responding to insect pests, and protecting high-quality streams.
Read more about the Resilient Forests Initiative

Preventing the Extinction of Hawaiian Forest Birds

'i'iwi on 'iliahi (Haleakalā sandalwood), Haleakalā National Park.

NPS / David Yates

At Haleakalā National Park, the Pacific Island Network is leading a multi-agency effort to prevent the extinction of Hawaiian forest birds. The network has led all aspects of acquiring, planning, and allocating $13.2 million in funding to launch a novel program using the incompatible insect technique (IIT) to protect forest birds from avian malaria. Mosquitoes and avian malaria are non-native to Hawaiʻi, and native forest birds have no resistance to the disease. While forest birds previously found refuge at elevations where it was too cold for mosquitoes (and avian malaria) to survive, the warming climate has allowed mosquitoes to creep higher into the birds’ range. Many Hawaiian forest bird species have already gone extinct or disappeared from the lower portions of their ranges. Without immediate action, several endangered species will go extinct entirely within the next decade, and ultimately 12 of 17 remaining native species will be lost.

The IIT works by preventing mosquito reproduction. About half of all insects carry an intracellular parasite called Wolbachia. Mosquitoes infected with different strains of Wolbachia are reproductively incompatible. When they mate, the eggs are nonviable, and do not hatch. Using the IIT, scientists release 500,000 incompatible male mosquitoes a week to swarm wild females. When this occurs, eggs produce no offspring. Over time, the mosquito population declines—along with rates of avian malaria.

This is the first time IIT has been used for conservation purposes. The program required extensive technical and regulatory work under an aggressive timeline. Its success has been a direct result of I&M monitoring data, scientific expertise, and partnerships developed by the Pacific Island Network over the past decade. Now, landscape-scale management has the potential to quickly protect the vast majority of endangered forest bird habitat at Haleakalā. This program lays the groundwork for standing up similar programs in Hawaiʻi Volcanoes National Park and other critical habitat in Hawaiʻi, and provides a model for how the NPS can use innovative techniques to address a wide range of invasive species and human health concerns in parks. This project has received funding from BIL, IRA, and a number of other partner sources, including the US Department of Interior, the State of Hawaiʻi, and non-governmental organizations.
Read more about protecting Hawaiian forest birds

Conservation of Whitebark Pine Across the West

Long-term whitebark pine monitoring plots at Yellowstone National Park.

NPS / Jacob W. Frank

In some high-elevation areas from the Sierra Nevada to the Pacific Northwest and northern Rocky Mountains, whitebark pine (Pinus albicaulis) can make all the difference between barren treeless slopes and diverse plant and animal communities. A hardy tree that can tolerate the harsh and dry conditions near treeline, whitebark pine is a keystone species that enhances its environment for other species. Stands of whitebark pine slow erosion, and the seeds found in pinecones are a valuable high-energy food source for birds and mammals. But whitebark pine populations are on the decline. Stressors like white pine blister rust, native mountain pine beetle, and intense wildfire—all exacerbated by climate change—contributed to the species’ listing as “Threatened” under the Endangered Species Act in January 2023. Because of its importance to alpine ecosystems, whitebark pine is the subject of long-term vital signs monitoring in multiple I&M networks.

The Greater Yellowstone Network leads a longstanding multiagency collaboration to monitor whitebark pine trends and conditions on NPS, US Forest Service, and Bureau of Land Management lands within the Greater Yellowstone Ecosystem. Network data and staff expertise contributed not only to the Species Status Assessment that led to the listing, but also to the US Fish and Wildlife Service’s Recovery Action Plan. The network has also engaged in collaborative research on how much white pine blister rust cankers grow from year to year, co-led the NPS Five-Needle Pine team, and helped to secure BIL and IRA funding for whitebark pine restoration that includes a strong collaboration with the non-profit, American Forests. Network vegetation ecologists shared their knowledge with the public by publishing collaborative research about white pine blister rust. They also participated in films by American Forests, the Ricketts Foundation, and the Cornell Lab of Ornithology, such as Hope and Restoration: Saving the Whitebark Pine.

A young whitebark pine growing next to an Englemann spruce at Glacier National Park.

NPS photo

Although whitebark populations in the Sierra Nevada Network (SIEN) remained relatively healthy until recently, emerging mortality and dieback have prompted increased attention from the network. Network staff have worked with partners from the US Geological Survey and US Forest Service (USFS) to launch an I&M-led study to identify the causes and distribution of mortality in Yosemite, Sequoia, and Kings Canyon national parks. Data from the study will contribute to the development of remote-sensing tools for early detection currently being tested by USFS specialists. These tools would complement the I&M plot-based monitoring program.

In the wake of the federal listing of whitebark pine, the network participated in the development of a multi-park, cross-network assessment of proposed restoration and recovery projects at Devils Postpile National Monument and Lassen Volcanic, Kings Canyon, Sequoia, and Yosemite national parks. The assessment relied heavily on I&M inventory products and monitoring data, as well as the experience of I&M and USFS colleagues. This document will set the stage for park managers to proceed with research, restoration, recovery, and management actions in whitebark pine habitat throughout the Sierra. Further north, the North Coast and Cascades Network secured funding to identify high-priority whitebark pine individuals for conservation, cone collection, and management tools across Mount Rainier, North Cascades, and Olympic national parks.

Other networks involved in collaborative five-needle pine monitoring (whitebark, bristlecone, foxtail, and limber pine) include the Klamath, Mojave Desert, Rocky Mountain, and Upper Columbia Basin networks. The NPS Five-Needle Pine Team (17 parks, 6 networks) has provided a forum for parks with five-needle pines to share information, collaborate on projects, and engage in real-time problemsolving. The team’s projects have received more than $2M in BIL and IRA funding to support seed collection, plant blister rust-resistant seeds and saplings, and do modeling to determine the best locations for planting.
Read more about whitebark pine conservation efforts

Science for Management: Making a Difference

To learn more about how the Inventory & Monitoring Division is helping strengthen the sustainability and resilience of national park ecosystems, visit Making a Difference.