Ventana Wildlife Society Biologist Mike Stake and Conservation Ecologist Dr. Brian Woodward conduct a Raptor survey on The Preserve. Photo by Alix Soliman.
March 25, 2022
By Alix Soliman
Soaring overhead on rising thermals, dive-bombing rodents in the rolling grasslands with their piercing screeches echoing off of the hills – birds of prey are a striking sight in the Santa Lucia Mountains. Raptors, or predatory birds, have characteristically hooked beaks, sharp talons, and powerful eyesight that give them the ability to zero in on their prey. In fact, the word raptor stems from the Latin rapere, which means to seize or plunder. It’s raptor breeding season right now, which makes it an especially good time to venture out and observe these birds as they mate and nest.
Each year, the Conservancy partners with Mike Stake, Senior Wildlife Biologist at Ventana Wildlife Society, to conduct surveys on The Santa Lucia Preserve in an effort to monitor raptor populations. Understanding how populations of sky-faring predators change over time gives us a better idea of what’s happening with their prey species on the ground. As key indicator species, “understanding raptor populations also indirectly helps us understand rodent populations,” Conservation Ecologist Dr. Brian Woodward says. Giving us one piece of the larger ecological picture, this data helps the Conservancy evaluate whether our efforts to protect habitat and promote conservation-compatible residences are working, particularly in our grasslands and oak savannas.
For instance, if enough Preserve residents were to use rodenticides rather than the recommended Integrated Pest Management (IPM), we could see a cascading negative impact on raptor populations, among other predators. That said, we must also grasp that raptors on The Preserve don’t exist in a vacuum; populations here often reflect what scientists are seeing at a regional level and may also be tied to climatic factors.
The survey method is relatively simple. We visit the same 34 locations (known as “raptor points”) in February, April, and June, making sure to get all of the points done within the same 4 hour window over a period of two days in order to decrease the potential for variation in the data. As with all scientific methods, “the goal is standardization,” Mike says with his eyes on the horizon. “If we can keep everything the same every year, we can get a better idea of how the population has changed over time.”
At each raptor point, we set a timer for 5 minutes and scan the surrounding landscape 360 degrees with our binoculars, especially the tops of trees and other high perch locations, recording the species and number of each raptor we see or hear. Situated within a major north-south bird migration path known as the Pacific Flyway, 28 species of raptors have been documented on the Santa Lucia Preserve over the years. Of those species, here is a selection of 7 common species that you can learn to identify: