West of I-25 SE Deer Data Analysis Units Herd Management Plan

CPW is revising herd management plans for the five mule deer herds located west of I-25 in Southeastern Colorado. Public engagement will help identify significant management issues as well as assist in determining acceptable management actions for these herds. Feedback will be accepted from August 15 to September 19, 2025, and input can be provided in the form below.

Background

Colorado Parks and Wildlife (CPW) manages five mule deer herds west of I-25 in the Southeast Region (see descriptions and map below). CPW is currently revising the herd management plans (HMPs) for these five herds. The HMPs will identify desired population and buck-to-doe ratio objectives that will guide mule deer management for a 10-year time frame. Public input is an important part of the planning process, and we are interested in your input on mule deer management in these herds. The information you provide will help guide the management of the five SE Region West of I-25 mule deer herds from 2026-2036.

SE Region West of I-25 Mule Deer Herds

Cottonwood Creek D-15 Mule Deer Herd

• Game Management Units 48, 56, 481, and 561.

• Primarily located in western Chaffee County in central Colorado.

• Bounded on the north and west by the Continental Divide, on the east by the Arkansas River, and on the south by the divide between the Arkansas and Rio Grande drainages and the Chaffee/Fremont county line

Cripple Creek D-16 Mule Deer Herd

• Game Management Units 49, 57, 58, and 581

• Includes portions of Park, Teller, Fremont, Chaffee, and Lake Counties

• Bounded on the north by the Continental Divide, Colorado Hwy 9, and U.S. Hwys 285 and 24; on the east by Colorado Hwy 67 and the Phantom Canyon Road (Fremont County Road 67); on the south by U.S. Hwy 50 and the Arkansas River; and on the west by the Arkansas River.

Trinidad D-32 Mule Deer Herd

• Game Management Units 85, 140, and 851.

• Includes portions of Costilla, Huerfanom, and Las Animas Counties

• Bounded on the north by US highway 69, Interstate 25, and Colorado 160; on the east by Colorado 389; on the south by the New Mexico and Colorado State line; and on the west by the Sangre de Cristo Divide, Huerfano County Roads #570 and #572 (Pass Creek Road) and Huerfano County Road #555 (Muddy Creek Road).

Wet Mountain D-34 Mule Deer Herd

• Game Management Units 69, 84, 86, 691, and 861

• Includes portions of Fremont, Custer, Huerfano, and Pueblo Counties

• Bounded on the north by US Highway 50; on the east by Interstate 25; on the south by Colorado 69, Huerfano County Road #555 (Muddy Creek Road and Huerfano County Roads #570 and #572 (Pass Creek Road); and on the west by the Sangre de Cristo Divide.

Rampart D-50 Mule Deer Herd

• Game Management Units 59, 511, 512, and 591

• Includes portions of El Paso, Teller, Fremont, and Pueblo Counties

• Bounded on the north by the Teller/Douglas county line; on the east by Interstate 25; on the south by Highway 50; and on the west by the Platte River, Highway 24, Highway 67 and the Phantom Canyon Road.

Reason for prioritizing the revision of these five deer herd management plans now

Deer HMPs incorporate public input, habitat capabilities, chronic wasting disease management, and herd considerations into management objectives. There is a need to update population and buck-to-doe ratio objectives for the five SE Region mule deer herds to better align with the purpose of HMPs and guide CPW’s deer management practices. Population models and field data indicate that current objectives are not biologically realistic for these five herds. Three of herds have remained static after decades of low female harvest and have not approached the current population objectives. Therefore, the revised objectives will align population objectives with herd carrying capacity.

CPW is completing the Upper Arkansas Lion-Deer Predator Study in D-16 and D-34 and during this time the management strategies, including objectives, were left unchanged for the two deer herds. Since the research is finishing, management strategies for these herds can now be revised. These two herds, along with D-15, are chronically below the current population objectives.

Another important consideration is Chronic Wasting Disease (CWD) management. 2024 was a mandatory testing year for D-15 and D-50 deer herds, as well as several eastern plains deer herds. During this time the first CWD positive deer was detected in D-15. Except D-50, CWD rates are generally low for the deer herds west of I-25 in the SE Region, but there is concern about the disease continuing to march west. Additionally, there is the need to update the buck-to-doe ratio objectives. Management for buck-to-doe objectives helps with CWD management and three herds are chronically below current objectives.

Current Engagement and Next Steps

CPW will be accepting feedback on revising herd management plans for the five mule deer herds located west of I-25 in Southeastern Colorado from August 15 to September 19, 2025 and input can be provided in the form below. The next step will be to prepare the draft plan for a 30 day comment period.