SMC professor researches effect of genetics, climate change on birds
Allison Sanchez | Thursday, September 15, 2016
Saint Mary’s assistant biology professor Joel Ralston is studying a population of northern boreal forest birds to determine if climate-driven changes will impact species distributions and genetic diversity. He has been using a field study of wild birds, genetics and computer modeling to test what influence climate change will have on the population.
“It is generally thought that as climates warm, species will move northward or up in elevation to track their ideal conditions,” Ralston said. “This means that populations at the southern edge of their current ranges may be the first to disappear due to climate change and any unique genetic diversity held in those populations could be lost.”
Ralston said his interest in species distributions had made it nearly impossible to avoid climate change.
“Warming temperatures are already having big effects on wildlife,” he said. “Distributions are changing, populations are declining, birds are migrating earlier each year and some studies have shown that nearly half of all North American birds are threatened by climate change.”
Saint Mary’s seniors Kathryn Marshall, Emily Crimmins and Emilie Vanneste have given Ralston aid in this study, as well as colleagues around the country and student participants from Ralston’s previous college (Editor’s note: Marshall is a News writer for The Observer).
A portion of the summer was spent capturing birds in 30- to 40-foot mist nets with Marshall, Ralston said.
“We placed the nets in the bird’s appropriate habitat and opened them up really early in the morning — just before sunrise usually — so that it is still dark enough that the birds couldn’t see the net,” he said. “Then we’d wait patiently for a bird to fly through and crash into the net.”
Ralston said it is important to study birds because they are vital for the ecosystems they live in and can be used as a means to study the effects of environmental pollutants, human urban development and climate change.
“Bird study is also very important in providing early warnings of issues that may be affecting ecosystems as a whole,” he said. “Because birds are relatively easy to observe, biologists often notice changes in bird populations before other types of organisms.”
In a recent study, Ralston and his colleagues found that certain species of birds are disappearing from their current distributions and are unable to move to new sites as a response to climate change.
“I think this [study] is important because it shows that you can help birds persist through climate change,” he said. “By taking actions that we know help birds — keeping your cats indoors, preventing window collisions, putting out bird feeders, planting native plants in your yards — we will be building up bird populations and helping them naturally respond to climate change.”