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As global temperatures rise, many species are scrambling to adapt—or risk extinction. Scientists refer to these animals as "species on the move," but new research suggests the scientific community may be overlooking the wide variety of ways these species are adapting.

In a May 8 "idea paper" in Trends in Ecology & Evolution, UC Santa Cruz marine ecologist Alexa Fredston and a team of international researchers argue that most studies of species on the move focus on a single climate adaptation strategy—like northward migrations or shifting breeding times—while ignoring others.

That narrow lens, they warn, can obscure how species are really coping with climate change and lead to less effective conservation efforts. Their paper outlines a new framework for capturing how species use a combination of climate adaptations and offers tools researchers can use to make their work more comprehensive and actionable.

"The picture that we all have in our heads for species on the move, we're arguing, is not quite sophisticated enough," Fredston said.

Overlooking adaptations

The authors divide climate adaptations employed by species on the move into strategies across space—such as traveling north to find cooler climates or traveling vertically, to higher altitudes—and time, such as migrating earlier in the year or venturing out later in the day.

When researchers plan a study, they have to decide on which things to observe, and the methods they choose can vary broadly based on that decision. In their paper, the authors illustrate these decisions using the study of tree frogs as an example.

One researcher might choose to measure whether the frogs are moving farther north, another researcher might examine whether the frogs are moving higher into the breezy tree canopy and a third researcher might explore whether the frogs are shifting their mating season to cooler months. Any one of these studies could fail to detect whether the tree frog species is using a different adaptation strategy, or a combination of strategies.

Humans, Fredston pointed out, are an example of a species that adapts to climate using a combination of strategies. "You might not go outside in the middle of the day when it's really hot, or you might move states if you don't like your climate anymore," she said. "And you could do one or the other, or neither or both."

The authors of the paper, including UC Santa Cruz ecology and evolutionary biologist Malin Pinsky, implore researchers to design studies that can capture multiple climate response strategies.

Monte Neate-Clegg, a postdoctoral fellow at UC Santa Cruz and co-author on the paper, has applied this way of thinking to his own research. In a previous study of birds adapting to climate change conducted at UC Los Angeles, Neate-Clegg measured three adaptation strategies: How far various species were shifting their habitat northward, how much they were moving to higher elevations across mountain ranges and whether they were shifting the timing of their breeding season.

He found that the birds were using a combination of these adaptation strategies, but that the breeding season shift accounted for two-thirds of their overall adaptation. Had Neate-Clegg only studied the birds' spatial strategies, he would have missed a majority of the animals' approach to surviving climate change.

"This more holistic approach tells us their overall ability to track climate change and emphasizes which aspects of climate tracking are potentially easier for different species," Neate-Clegg said.

Understanding the most important adaptation strategy for a species can help shape conservation efforts, Neate-Clegg said. For example, if a species seeking cooler temperatures is more likely to move up in altitude rather than farther north, conservationists can maximize their efforts to help that species find a home further off the ground.

"We can target conservation towards that particular strategy," Neate-Clegg said.

A new approach to research

In addition to pointing out the pitfalls of current research methods, the authors introduce a number of ways scientists can broaden their studies to account for multiple adaptation strategies. One suggestion is to expand annual surveys to occur multiple times per year, allowing researchers to detect how species may be changing their seasonal behavior.

The authors also suggest that researchers studying species shifting their habitats across large geographic regions could also measure changes in altitude and depth within those regions.

Given that expanding the scope of a research study can require additional time and money, the authors suggest making it easier to combine observations from multiple studies. This will require scientists to publish their data with sufficient documentation so that other researchers can easily merge multiple datasets.

Researchers could use more sophisticated analysis methods in order to glean findings from these expansive datasets, including machine learning and artificial intelligence tools.

Supplementing observational research with findings from experimental studies can determine the adaptation strategies species are likely to use with a higher degree of accuracy.

This paper aims to build on existing research by proposing a more comprehensive approach to studying species on the move, Fredston explained. "More than anything, we're critiquing our own past work and challenging ourselves to do better."