Raptor Migration Research

I have been interested in raptors (particularly golden eagles) and their migration for many years. Through the pioneering efforts of nearby Hawk Mountain Sanctuary and other hawkwatch sites, the Kittatinny Ridge (a.k.a. Blue Mountain) in Pennsylvania is well known for its fall hawk migration. Much less is known about migration on other ridges, and on a regional scale, how migrating raptors choose their routes along the Appalachian Mountain chain. Recently I have been collaborating with scientists from The National Aviary, Powdermill Nature Reserve of Carnegie Museum of Natural History, and Hawk Mountain Sanctuary to better understand, quantify, and model how golden eagles react to terrain during migration.

     

The impetus for the work is wind energy development, rapidly occurring throughout the central Appalachian region, particularly in the higher elevations. We are focused on golden eagles as an indicator species, because available data suggests that their small, isolated eastern population may be at particular risk from ridgetop wind turbines along their migration paths and wintering area in the southern Appalachians. However, there is currently very little data on how turbines impact migrating raptors, and thus much uncertainty about the risks posed to raptors. The project has two components: 1) satellite tracking of golden eagles using state-of-the-art Argos GPS PTTs (see above left picture), and 2) mathematical modeling of migration using high resolution spatial datasets and driven by hourly weather data.

Link to FlightPath model BETA release

Further information about our project can be found at the links below:

Read our Position paper on risks posed by wind turbines to raptors

Link to Tussey Mountain Spring Eaglewatch

Recent presentation on Appalachian Wind Energy and Raptor Migration


Recent publications & presentations on raptor migration

Brandes, D. 2008. Appalachian wind energy development and migrating raptors: a collision course? Conservation through Education Lecture Series, East Stroudsburg University.

Brandes, D., Katzner, T., Miller, T., Lanzone, M., Bildstein, K., and D. Ombalski. 2007. A Terrain-based Dynamic Model for Simulating Raptor Migration through the Applachians. Raptor Research Foundation & Hawk Migration Association of North America 2007 Joint Meeting. PDF version.

Miller, T., Brandes, D., Lanzone, M., Ombalski, D., Mulvihill, R., Brooks, R., and T. Katzner. 2007. Flight Characteristics of Golden Eagles (Aquila chrysaetos) Migrating Through Eastern North America as Determined by GPS Telemetry. Raptor Research Foundation & Hawk Migration Association of North America 2007 Joint Meeting.

Lanzone, M., Miller, T., Brandes, D., Ombalski, D., Mulvihill, R., and T. Katzner. 2007. Golden Eagle(Aquila chrysaetos) Wintering Behavior in the Appalachian Mountains of Eastern North America using GPS Data from Satellite Telemetry. Raptor Research Foundation & Hawk Migration Association of North America 2007 Joint Meeting.

Brandes, D. 2007. Raptor migration and the siting of utility-scale wind energy plants in Pennsylvania. Invited presentation at the Pennsylvania Wind-Wildlife Collaborative Technical Workshop.

Brandes, D. 2006. Wind Power Development and Raptor Migration in the Central Appalachians. HMANA Hawk Migration Studies 31(2): 20-25.

Ombalski, D., and D. Brandes. 2006. Pennsylvania Comprehensive Wildlife Conservation Strategy (CWCS) Species Assessment – Golden Eagle, Aquila chrysaetos.

Brandes, D. 2005. Trickles of raptors: modeling migration with a fluid flow analogy. Invited presentation to the Raptor Society of Metropolitan Washington.

Brandes, D. and D.W. Ombalski, 2004. Modeling raptor migration pathways using a fluid flow analogy. J. Raptor Res. 38(3): 195-207. PDF version.