"Biologists and ecologists are only beginning to recognize the value of incorporating the vertical aspect into analyses, which more realistically represents the space used by an animal," added Tracy, who developed the key algorithm vital to this research.
One aspect of the study focused on learning more about the range and movements of the California condor. While its population now stands at approximately 400 birds up from only 22 in the mid- 1980s conservation efforts to reintroduce this ecologically-important species to its former habitat in the mountains of California and Mexico have been hampered by a lack of understanding about condor movement patterns and habitat use. To address this, the San Diego researchers have been attaching miniaturized GPS biotelemetry units to every condor that it releases into the wild, to gather valuable tracking data.
"We have been calculating home ranges for the tracked condors in three dimensions for the first time using this GPS location data, and our novel density estimator was used to incorporate the vertical component of animal movements into projections of space-use," said Sheppard.
Although the team successfully developed appropriate algorithms for creating 3D home ranges, actually extending animal home range volumes into 3D is computationally demanding, especially for animals tracked using highly accurate GPS telemetry devices for which high-resolution home ranges should be calculated to capitalize on the fine-scale location data collected.
"It is also highly computationally intensive to generate 3D home ranges from GPS telemetry data collected fr
|Contact: Jan Zverina|
University of California - San Diego