"The system's extensive matrix capabilities enable me to perform all kinds of simple stochastic simulations."

Taking Threatened Species under Our Wing

California is proud of its status as one of the states with the highest diversity of plant and animal species in the U.S. But as more and more people choose to call California home, this source of pride is in a fragile condition. One of the states with the fastest growing human population, California is now also home to one of the highest numbers of threatened and endangered species in the U.S. Without help, their next stop: extinction.

Researchers at the Institute for Bird Populations are providing the data needed to keep as many of those species as possible from disappearing. To analyze that data, research scientists like Dan Rosenberg use Mathematica.

"The data will help us get at the cause of the declines and assess possible management solutions," explains Rosenberg. "We use Mathematica to assist in estimating such things as how many birds of a given species are present in certain populations, and we've started using it as a tool to simulate population responses to changes in the birth and death rates." As a nonprofit organization focused on fostering a global approach to studies of bird populations, the Institute expects these types of simulations to contribute to bird conservation efforts worldwide.

One subject of study at the moment is the burrowing owl. Once found all over California, its habitat is now largely confined to the Central and Imperial Valley regions. Loss of habitat is likely the primary reason for the owl's demise, but intensive agriculture practices such as the use of high levels of pesticides in agricultural areas where the owls nest and forage, or the poisoning of ground squirrels who build the burrows where burrowing owls eventually nest, may also be responsible. Solutions amenable to agriculture, development, and healthy populations of burrowing owls are being sought.

Nothing can be sure, however, until researchers understand more about owl demographics such as birth, death, and movement rates. "We perform randomization tests and probability studies with Mathematica to simulate test methods for estimating how these demographic traits have and will affect population dynamics and ultimately the health of burrowing owl populations, as well as populations of other species," says Rosenberg. "I'm still a novice user, but I suspect Mathematica may become an integral part of my research as I learn more."

Hopefully researchers' results will teach us how to keep more of our feathered friends around.

Key features of Mathematica used:

• Numeric--matrix calculations, lists, statistics, probability calculations
• Graphic