Field testing an "acoustic lighthouse": Combined acoustic and visual cues provide a multimodal solution that reduces avian collision risk with tall human-made structures.

Billions of birds fatally collide with human-made structures each year. These mortalities have consequences for population viability and conservation of endangered species. This source of human-wildlife conflict also places constraints on various industries.

Ontogeny of Flight Capacity and Pectoralis Function in a Precocial Ground Bird (Alectoris chukar).

Flight is the defining characteristic of birds, yet the mechanisms through which flight ability develops are only beginning to be understood. Wing-assisted incline running (WAIR) and controlled flapping descent (CFD) are behaviors that may offer significant adaptive benefits to developing birds. Recent research into these forms of locomotion has focused on species with precocial development, with a particularly rich data set from chukar partridge (Alectoris chukar).

3D for the people: multi-camera motion capture in the field with consumer-grade cameras and open source software.

Ecological, behavioral and biomechanical studies often need to quantify animal movement and behavior in three dimensions. In laboratory studies, a common tool to accomplish these measurements is the use of multiple, calibrated high-speed cameras. Until very recently, the complexity, weight and cost of such cameras have made their deployment in field situations risky; furthermore, such cameras are not affordable to many researchers.

Flapping before Flight: High Resolution, Three-Dimensional Skeletal Kinematics of Wings and Legs during Avian Development.

Some of the greatest transformations in vertebrate history involve developmental and evolutionary origins of avian flight. Flight is the most power-demanding mode of locomotion, and volant adult birds have many anatomical features that presumably help meet these demands. However, juvenile birds, like the first winged dinosaurs, lack many hallmarks of advanced flight capacity.

The mechanics and behavior of cliff swallows during tandem flights.

Cliff swallows (Petrochelidon pyrrhonota) are highly maneuverable social birds that often forage and fly in large open spaces. Here we used multi-camera videography to measure the three-dimensional kinematics of their natural flight maneuvers in the field. Specifically, we collected data on tandem flights, defined as two birds maneuvering together.

A protocol and calibration method for accurate multi-camera field videography.

Stereo videography is a powerful technique for quantifying the kinematics and behavior of animals, but it can be challenging to use in an outdoor field setting. We here present a workflow and associated software for performing calibration of cameras placed in a field setting and estimating the accuracy of the resulting stereoscopic reconstructions. We demonstrate the workflow through example stereoscopic reconstructions of bat and bird flight.

The broad range of contractile behaviour of the avian pectoralis: functional and evolutionary implications.

Wing-assisted incline running (WAIR) in birds combines the use of the wings and hindlimbs to ascend otherwise insurmountable obstacles. It is a means of escape in precocial birds before they are able to fly, and it is used by a variety of juvenile and adult birds as an alternative to flight for exploiting complex three-dimensional environments at the interface of the ground and air. WAIR and controlled flapping descent (CFD) are the bases of the ontogenetic-transitional wing hypothesis, wherein WAIR and CFD are proposed to be extant biomechanical analogs for incremental adaptive stages in the evolutionary origin of flight.

Scaling of mechanical power output during burst escape flight in the Corvidae.

Avian locomotor burst performance (e.g. acceleration, maneuverability) decreases with increasing body size and has significant implications for the survivorship, ecology and evolution of birds.

When hatchlings outperform adults: locomotor development in Australian brush turkeys (Alectura lathami, Galliformes).

Within Galliformes, megapods (brush turkey, malleefowl, scrubfowl) exhibit unique forms of parental care and growth. Hatchlings receive no post-hatching parental care and exhibit the most exaggerated precocial development of all extant birds, hatching with fully developed, flight-capable forelimbs. Rather than flying up to safety, young birds preferentially employ wing-assisted incline running.

Precocial development of locomotor performance in a ground-dwelling bird (Alectoris chukar): negotiating a three-dimensional terrestrial environment.

Developing animals are particularly vulnerable to predation. Hence, precocial young of many taxa develop predator escape performance that rivals that of adults. Ontogenetically unique among vertebrates, birds transition from hind limb to forelimb dependence for escape behaviours, so developmental investment for immediate gains in running performance may impair flight performance later.

A fundamental avian wing-stroke provides a new perspective on the evolution of flight.

The evolution of avian flight remains one of biology's major controversies, with a long history of functional interpretations of fossil forms given as evidence for either an arboreal or cursorial origin of flight. Despite repeated emphasis on the 'wing-stroke' as a necessary avenue of investigation for addressing the evolution of flight, no empirical data exist on wing-stroke dynamics in an experimental evolutionary context. Here we present the first comparison of wing-stroke kinematics of the primary locomotor modes (descending flight and incline flap-running) that lead to level-flapping flight in juvenile ground birds throughout development.