Sometimes scientists study current problems. Scientists also study problems that may occur in the future. To study what may happen in the future, scientists look at current evidence and make predictions about what might happen.

In this study, the scientists were interested in how a changing climate may affect wildlife in the future. Scientists have tried to figure out the effects of climate change using several different methods. The method the scientists used in this study was to create a vulnerability index. A vulnerability index predicts how much a species might be affected by changes to their habitat. The scientists used this vulnerability index to predict which species of wildlife were likely to be the most vulnerable to climate change. This process enables people who work to conserve wildlife to make better decisions.

Have you heard the term “climate change?” Climate change refers to how Earth’s climate may be changing over time. In the past few years, most scientists have agreed that measured and recorded changes in Earth’s climate over the past 100 or more years point to a warming of Earth’s surface.

Scientists are researching questions related to the possible effects of climate change. One question is: How do different plant and animal species respond to a changing climate? In this study, scientists were interested in how some vertebrates may respond to climate change (figure 1).

Identifying which species may be the most vulnerable to a changing climate is important. This information can help people make decisions about how to best manage the land. It can also help make better decisions to support wildlife. In this study, the scientists wanted to learn more about species living in and around the Coronado National Forest (CNF) (figure 2).

The CNF is located in southeast Arizona and southwest New Mexico (figure 3). The scientists identified 30 species to study.

The 30 species the scientists studied included reptiles, amphibians, birds, and mammals (figures 4, 5a, & 5b). Some of these 30 species were important to study because they were considered at risk of extinction. Some of the species were already listed as an Endangered Species or a Federal Species of Concern.

The scientists in this study were interested in discovering how climate change may affect the 30 species they studied. The scientists wanted to figure out how vulnerable the species may be to climate change.

To figure out which species were likely to be the most vulnerable to the effects of climate change, the scientists used a vulnerability index. The scientists answered 25 questions for each species. The 25 questions were grouped into four categories.

The four categories were habitat, physiology (fi zē ä lə jē), phenology (fi nä lə jē), and biotic (bī ä tik) interactions. The habitat category covered topics about where an animal lives. The physiology category covered topics related to the function and activities of the animal.

Phenology is the study of the relationship between climate and events in the annual life cycle of plants and animals. Example topics in the phenology category are bird migration and plant flowering. Migration is when an animal moves from one region or climate to another for feeding or breeding.

Biotic interactions are the ways that living things interact with each other. The questions in this category related to how these interactions might change due to a changing climate. Examples of the types of questions the scientists answered are shown in figure 6.

The scientists answered these types of questions for each of the species in their study. Each question was scored a point value depending on the answer to the question. The scientists calculated an overall score for each species using points from answers to all 25 questions.

The scientists also calculated a score for each species in each of the four categories (using points from only the questions within the category).

In addition, the scientists calculated a score for the four different taxonomic groups they studied. They calculated this score by taking the average of the overall score for each species in a taxonomic group. The four taxonomic groups that were studied were birds, mammals, amphibians, and reptiles.

In summary, the scientists calculated three scores: 1) an overall score for each species; 2) a score for each category for each species; and 3) a taxonomic group score.

The scientists found that most of the species were vulnerable to climate change. The overall score ranged from -0.4 to 9.9. The larger the overall score, the more vulnerable the species was to a changing climate.

Sixty-seven percent of the species identified had a score over 5. These were the species most vulnerable to climate change. The two species with the largest scores were the elegant trogon (trō gän) and the Tarahumara (ta rə hü mär ə) frog (figures 7 & 8). The lowest scoring species were the mesquite mouse, the desert bighorn sheep (see photo, upper right), and Slevin’s bunchgrass lizard. These three species were predicted to be the least vulnerable to climate change.

Scientists calculated scores for each species within the four categories. The scores ranged from -2.3 to 5 for habitat, physiology, and phenology. The closer the score was to 5, the more vulnerable the species was predicted to be in that category (figure 9).

When the scientists looked at the different taxonomic groups they studied, they found that the bird group had the highest average overall score and the reptile group had the lowest average overall score (figure 10).

The scientists concluded that most of the 30 species are vulnerable to a changing climate. The scientists suggested that the scores for each species may be used as a guide. These scores may help guide which species should be studied more right now. Also, the scientists believe it is important to look at the individual characteristics of each species. These individual characteristics may have an impact on the vulnerability of a species.

The scientists also said it was important to consider the overall score as well as the scores within the categories (habitat, phenology, physiology, and biotic interactions). For example, the elegant trogon and Tarahumara frog had the same overall score. However, they had different scores within the four categories. The scores within the categories may help scientists know which areas need more study.