Big Bend National Park fires may benefit select bird species

By Robyn Sanders

Birds in Big Bend National Park may suffer few ill effects from climate change and wildfires in the future — and could even be better off, a Baylor study has found.

The study, published this year, was co-authored by Dr. Joseph White, associate professor of biology, Dr. Kevin Gutzwiller, professor of biology, and Dr. Wylie Barrow Jr., a research wildlife biologist at the U.S. Geological Survey.

The study is published in Conservation Biology, an online journal.

Three specific bird species — the Scaled Quail, the Rock Wren and the Loggerhead Shrike — could be less affected by climate change and wildfires in the future, according to the research.

This is because as the climate changes, the grasslands will dry out, providing more open areas for these birds to find food, as well as providing less fuel for wildfires, White said.

“The frequency of fires in deserts would go down with climate change,” White said.

As part of the research, birds were surveyed at 70 locations in Big Bend National Park over the course of three years, under the direction of Barrow.

“I spent three summers as well, mapping out the vegetation type and other characteristics. Then, using satellite data, produced maps of those,” White said. “Dr. Gutzwiller’s contribution was to take all of that information in a statistical model and build the landscape-bird-habitat relationships.”

White said the second part of his work was to write a model that used climate, vegetation types and topographical data to predict how vegetation types would change over time.

The model also simulated wildfire conditions in which the fire was, or was not, extinguished.

Using this data, a prediction was produced of how different bird species would be affected over the next 50 years by climate change and wildfires.

“I was somewhat surprised that simulated fire management (suppression) had little effect on projected vegetation composition,” Barrow wrote in an e-mail to the Lariat. “But once it was clear that there was less fuel for fire projected in the future (e.g., less projected grassland), it made sense.”

Previously there was a gap between researchers’ ability to say how vegetation might respond to changes in climate conditions and how those changes would impact wildlife, White said.

White, Barrow and Gutzwiller tried to address that gap with this research.

“If you had, say, an increase in temperature and then you said, well ‘x’ types of plants would be affected by that, the question then becomes what kind of wildlife are going to be affected either by the loss or the gain of that vegetation in a broad area, and what does that mean in terms of long-term sustainability of wildlife, particularly in a national park, because those are places that are geographically restricted,” White said.

“They have a definitive boundary, but the biology is transient because animals don’t see those borders, and climate obviously transcends it as well,” White continued.

This research was an attempt to build the connection between climate change and wildlife, White said.

“Climate change has differing effects on different species,” White said, “which could mean that common species could become even more common and more prevalent, and the rare species blink out of existence.”

White said he used satellite data from 1986 through 2000, and that during that period, the climate became drier and hotter, on average.

“So it indicates also that climate change isn’t something in the future, it’s also something from our past, and we’re in the middle of it,” White said.

The research was useful in showing how climate change can have an indirect effect on birds by affecting and influencing the vegetation in their habitat, Barrow said.

“If models, such as the one developed in this study, can accurately project responses of bird species distributions to projected changes in vegetation, then conservation biologists and land managers will be better informed in their activities to mitigate against changes in our planet’s vegetation that are anticipated due to our changing climate,” Barrow said.