Project period: 6 28 23-6 27 27PROJECT title: impacts of border barrier infrastructure on migratory birds along the lower RIO grande valley oftexasthe purpose of this project is to use several…

The U.S. Geological Survey (USGS) awarded a $299,995 Cooperative Agreement to the University of Delaware under the USGS Research and Data Collection program (CFDA 15.808). The project period is from June 28, 2023 to June 27, 2027. The purpose of this study is to quantify the impacts of U.S.-Mexico border barrier infrastructure on migratory bird habitat use and migration behavior in the Lower Rio Grande Valley of Texas. Key research activities include:

• Analyzing weather radar data, deploying acoustic and radio telemetry receivers, and conducting statistical analyses to determine how factors like distance from the border barrier, barrier type, land cover changes, and light pollution influence migratory bird densities and stopover habitat use.

• Developing fine-scale maps to help resource managers prioritize habitat conservation efforts for migratory birds.

• Providing recommendations to the Department of Homeland Security on mitigating potential negative impacts of the border wall infrastructure on migratory birds.

The University of Delaware, as the primary awardee, will disseminate research results through scientific publications, presentations, and public and agency reports.

Project period: 6 28 23-6 27 27PROJECT title: impacts of border barrier infrastructure on migratory birds along the lower RIO grande valley oftexasthe purpose of this project is to use several remote sensing technologies to quantify migratory bird habitat use and migration behavior in relation to barrier infrastructure along the US-mexico border within the lower RIO grande valley of texas. Will investigate how habitat modification and artificial light at night associated with the US border wall has influenced bird migration 1) at a broad spatial scale by comparing weather radar measures of bird numbers aloft during nighttime flights and on the ground during daytime stopovers before and after the installation of the wall barrier, and 2) at a fine scale by comparing differences in the diversity of bird species and the numbers of individual birds flying over walled versus unwalled segments of the border by recording the flight calls as they fly overhead at night and detecting radio-marked birds flying across the border using automated radio receivers. Will analyze weather radar data from the brownsville, TX radar (kbro) during spring and fall when birds typically migrate from 2005 to 2025. Will deploy 11 radio receivers and 11 audio recorders along the texas border to collect data during spring and fall. Will perform statistical analyses to determine how factors such as distance from border barrier, barrier type, current and recent changes in land cover, and distance from bright light at night are associated with seasonal bird densities in the air and on the ground during migration. Will develop fine-scale maps of where birds concentrate during migration and stopover within the lower RIO grande valley to help local, state, and federal resource management agencies prioritize current and future habitat acquisition, conservation, and restoration efforts targeted at migrating birds. Will use statistical models to make maps of predicted stopover use at specific areas of interest outside the weather radar domain but within the lower RIO grande valley as desired by management partners. Will also produce a dataset of acoustic and radio-tag detections of migrants by species across the array of sampling stations as well as associated metadata. Will disseminate research results to the scientific community through presentations at conferences and publication in scientific journals. Will also disseminate results via a project website to the public and via written reports to natural resource agencies. We will also provide recommendations for the department of homeland security for mitigating any negative impacts of border wall infrastructure on migratory birds. Understanding how migrating birds respond to habitat changes and light pollution will address multiple uncertainties underpinning management decisions and migratory populations identified by the gulf of mexico avian monitoring network. This project will benefit land managers and conservation planners, who have a critical need to understand how migratory bird passage and stopover habitat use are impacted by border wall infrastructure and associated light pollution and where limited funds should be invested for land protection and acquisition for passage migrants today as well as into the future.