Conservation Threats and Actions Needed
- Stabilize and expand deer populations
- Threat: Populations are small and isolated due to habitat loss and fragmentation.
- Actions Needed: Conduct translocations and population augmentations; and continue annual aerial population surveys and ground monitoring of doe-to-fawn ratios to estimate and track deer numbers.
- Habitat loss and degradation
- Threat: Loss of deciduous forested habitat.
- Actions Needed: Re-establish deciduous forested habitats (including expanding riparian vegetation, tree and shrub planting, water manipulation) available within the occupied range, and identify areas to restore deciduous forest outside the occupied range where feasible. Acquire and protect habitat. Improve habitat connectivity. Improve forage and browse availability (since body condition is related to survival and reproductive health).
- Disease response and mitigation
- Threat: Negative effects of infectious and communicable diseases.
- Action Needed: Collaborate with partners to ensure that Columbian white-tailed deer are included in emerging disease response plans.
- Climate change effects
- Threat: Loss of lowland habitat from more frequent and intense flooding.
- Actions Needed: Build and maintain water control structures on refuges, as needed, to manage water levels in sloughs and marshes. Consider construction of high-water refugia. Increase availability of and connectivity to suitable upland habitat.
- Resource information collection needs
- Threat: Suitable natural habitat is unstable and limited. There is a need to search for suitable habitat beyond what is currently occupied.
- Action Needed: Identify high quality upland habitat in areas that might support deer populations regardless of land ownership.
- Threat: Hybridization with black-tailed deer.
- Action Needed: Genetic sampling during future translocations to evaluate hybridization.
- Invasive and other problematic species
- Threat: Coyote predation causes high fawn mortality and has a disproportionate effect on small subpopulations.
- Action Needed: Continue efforts to control coyotes when needed.
- Threat: Invasive plants erode utility of habitats.
- Action Needed: Implement efforts to control invasive plants.
See the Climate vulnerability section for more information about the threats posed by climate change to this species.
Our Conservation Efforts
WDFW partners with federal and other state agencies, tribal government, conservation organizations and volunteers on various projects aimed at recovering Columbian white-tailed deer in their Columbia River range.
Partners have carried out activities to help bolster this population, including habitat protection and restoration, predator control, and translocating deer to enhance their numbers and expand their geographic range.
Recent research and conservation activities to benefit Columbian white-tailed deer have included:
- Translocation of Columbian white-tailed deer to expand deer to a new population on the Columbia Stock Ranch near Deer Island. Prior to this work, the site has undergone habitat enhancements including the planting of native trees and forage as well as the removal of non-native Himalayan blackberry. The site is owned by the Columbia Land Trust. The restoration is occurring in four phases and is expected to be completed by 2023.
- The Washington Department of Fish and Wildlife in partnership with Oregon Department of Fish and Wildlife (ODFW), U.S. Fish and Wildlife Service (USFWS), and the Cowlitz Tribe completed a Population-Habitat Viability Analysis (and a Population Viability Analysis) in 2020. This analysis (and recommendations therein) will shed light on several issues important to this species conservation and recovery.
- Recent deer counts have demonstrated that the translocation of deer from Julia Butler Hansen to Ridgefield National Wildlife Refuges appears to have been a success. In 2013 and 2014, 58 deer were translocated to the Ridgefield NWR. This population has not only grown to nearly 200 deer as of March 2020, but these deer have also moved across the river to populate areas in and around Sauvie Island in Oregon.
- The Columbian White-tailed Deer Habitat Connectivity Analysis was published the Washington Department of Transportation in October 2016. Technical support for this work came from WDFW, the Cowlitz Indian Tribe, USFWS, ODFW, and the Oregon Department of Transportation.