Environmental sensors equipped with climate monitors and Audiomoth microphones record sound at our research sites. Each sensor station is run with a Raspberery pi computer, which controls sampling protocols and pre-processes some of the collected data. For example, our stations are coded to only save sound files when bird calls are detected, and discard non-bird noises, such as human voices or traffic noise.

Once collected, we use machine learning algorithms to match known bird calls to our recordings, allowing us to identify the species of bird that has been detected. By monitoring bioacoustics in the environment over long-term time scales, we can better understand what birds are present in these coastal habitats across space and time. 

Collaborative biodiversity monitoring projects like eBird allow individuals to report bird sightings by submitting checklists of bird species identified while visiting a location. By accessing these datasets, we can obtain information on which bird species are observed at our research sites over time, in addition to giving us an idea of how many people may be visiting the site for recreational birding.

Ecotourism and bird festivals associated with migration stopover habitats have substantial economic impacts for local communities, and emphasize the cultural value of migratory birds for those engaging with them. By combining recreational birding data with bird occurrence records compiled from these observations, we can infer the association between migratory bird movement through coastal habitats and the impact they have on local communities. 

Our work is part of an international collaborative network of radio telemetry stations, the Motus Wildlife Tracking System. Through radio transmitter tagging, this network tracks more than 44,000 tagged organisms spanning 348 species, the majority of which are migratory birds. Each time a tagged animal passes within 2-15 km of a MOTUS station, a record is taken.

By establishing MOTUS stations in Port Aransas at the UT Marine Science Institute and at Fennessey Ranch, we can collect data on the identity and timing of migratory species presence in the region. In collaboration with the larger MOTUS network, which includes more than 1,700 stations globally, we can trace the migratory path that tagged birds follow before, during, and after appearing at our stations along the Gulf Coast.

For example, we detected a Franklin's Gull at Fennessey ranch on April 18, 2025. The previous detection for this individual was at the Estación Biológica Maritza in Costa Rica on November 17, 2024, which is a 2,279km journey! The insights gained from these collaborative connections help us better understand migratory bird flyways and the role of stop-over habitats in fueling birds on the move. More of our detections can be found on our MOTUS dashboard page.

Figure via Eschliman & Horton 2024

Weather radars work by emitting pulses of radio waves and collecting information on how the pulse is reflected back. The number and size of moving objects can be identified by quantifying their reflectivity. Velocity can be used to distinguish among objects. For example, birds generally fly at a velocity of 8-12 m/s, allowing them to be targeted and background noise, such as precipitation, to be removed. Additional metrics such as time of year, time of day, roost emergence patterns, and geographic range can be used to separate birds from other flying animals, such as bats and insects. Using this technology allows us to estimate the volume and timing of migratory bird movement through the Gulf Coast at the landscape scale.