Panorama’s very own Susanne Heim, Senior Environmental Scientist/Project Manager presented at the Wildlife Society Conference on the topic of habitat distribution models. The presentation, Evaluation of Desert Tortoise Habitat Suitability Model Predictions in the Soda Mountain Area, San Bernardino County takes a look at a desert tortoise habitat suitability model developed by the U.S. Geological Survey (USGS).

The presentation highlights the limitations of habitat suitability models. Susanne showed in her presentation that the desert tortoise habitat suitability model was not able to adequately predict the suitability of habitat within the Soda Mountain Valley. The results of multiple surveys that covered 100% of the Soda Mountain Valley  showed a lack of habitat. Only one tortoise was observed in four surveys. These survey results do not match the predictions made by the habitat suitability model, which predicts that the Soda Mountain Valley is highly suitable habitat for Desert Tortoise. 

Susanne identified that the model has some limitations, which could explain the discrepancy between the model prediction and the results of the field surveys. For example, the model does not take into account anthropogenic impacts, such as the four-lane highway, I-15, which divides the Soda Mountain Valley in half. The model also does not take into account the low incidence of tortoises near such a large highway. 

If you are interested in learning more about this subject, be sure to take a look at  Susanne’s presentation and Panorama’s white paper on the subject.