Developing an Integrated Population Model for Pronghorn in Texas
Request for Proposals November 2025

Introduction

Pronghorn restoration in the Trans-Pecos is a well-known conservation success story. Management and conservation of this population requires continued efforts, including additional translocations, predator removal, and habitat management, thereby inducing continued financial costs associated with these actions. Moreover, the Trans-Pecos experiences substantial environmental shifts and limitations that may influence vital metrics of the local pronghorn population. The source population for many of the translocations to the Trans-Pecos is from the northern Texas Panhandle, an area presumed to have a healthy pronghorn population when range conditions are good. Despite much attention towards Trans-Pecos pronghorn, very little research has been conducted on pronghorn in the Panhandle. Nonetheless, the Texas Panhandle continues to be a source for translocation efforts and understanding drivers of population dynamics for this important source herd is essential to maintaining translocation efforts to the Trans-Pecos and other areas in the state.

Texas Parks and Wildlife Department (TPWD) manages these two regional pronghorn populations somewhat differently based on population status and management goals. The Trans-Pecos population exists in an intensive management strategy, where more of a hands-on approach is taken. For instance, in 2025, around $134,000 was spent to remove coyotes during coyote breeding season (January to March) and prior to pronghorn fawning (May) in most herd units, and around $2,800,000 was spent over the last year and another $2,000,000 will be spent in the next 2 years to restore grasslands and modify/replace restrictive fencing to aid in long-term population success. Conversely, the Panhandle population has been managed in more of a hands-off approach relative to the Trans-Pecos. Panhandle pronghorn vital metrics are assumed to sustain the population as a source for translocation efforts in the absence of drought.

Many ungulates, including pronghorn, suffer fluctuations in population vital rates in response to environmental shifts and human induced changes to land cover. Nonetheless, adult survival tends to be stable in ungulate populations despite these climatic or landscape limitations, and juvenile survival is the primary indicator for overall population performance. To date, little information exists on juvenile survival and recruitment within Texas pronghorn populations.

Some recent research has been conducted in the Panhandle studying the influence of agriculture on pronghorn populations in the northwest and northeast Panhandle; however, fawn survivorship and more robust female survival, influences on fawn and female survival, and habitat use/movement data are needed for the Panhandle region to develop an accurate and functional Integrated Population Model (IPM). Therefore, objective 1 below will take place in the Panhandle first and foremost. More pronghorn data is available for the Trans-Pecos from recent research projects compared to the Panhandle, but more information in the Trans-Pecos, especially fawn survivorship, could be needed to better develop appropriate IPMs. Thus, objective 2 will address any additional data needed for the IPM for the Trans-Pecos.

Justification

The 2024 Land and Water Resource Conservation and Recreation plan contains three specific goals. Research to further our knowledge of influences on pronghorn neonate recruitment would fall within goal one and associated objectives:

• Practice, encourage and enable science-based conservation and stewardship of natural and cultural resources.
  • Be an exemplary steward of the public's lands and waters by using the best available science for ecosystem-based management.
  • Maintain the highest level of scientific validity and credibility.

Research Objectives

An expansive research project should be conducted to develop a functional IPM to improve management efficacy in pronghorn populations within the Panhandle and Trans-Pecos ecoregions under current management activities. The study design should address these main objectives:

1. Collect at least 3 years of pronghorn fawn and adult doe survival data in the Panhandle. Quantify fawn and adult doe survival and identify the most important environmental, landscape, population, or individual level predictors of mortality hazard.
2. As needed to supplement the existing data, collect at least 3 years of pronghorn fawn and adult doe survival data in the Trans-Pecos. Quantify fawn and adult doe survival and identify the most important environmental, landscape, population, or individual level predictors of mortality hazard.
3. Combine (1) existing Texas Panhandle and Trans-Pecos movement and survival data, (2) movement and survival data collected for this project, and (3) other movement and survival data in similar areas to develop an integrated population model (IPM) and use it to evaluate limiting factors that influence pronghorn population performance and thereby management decisions (i.e., permit issuance, surplus for translocations, most efficacious time to conduct predator management actions).

Expected Management Implications

This research project would deliver a detailed model that predicts pronghorn fawn and adult doe vital rates based on identified important variables (thereby annual estimates of population lambda) which can be used to determine management actions on an annual basis. Ultimately, this project should develop a combined Texas-specific integrated population model to predict population sustainability under varying climatic, landscape, predator, and management scenarios to be used as a tool for informed decision making.