LAKE TAHOE, Calif. – The iconic monarch butterfly, known for its striking orange and black coloration, migratory patterns, and love of milkweed, was recently proposed for federal protections by the U.S. Fish and Wildlife Service. But butterflies all over the West have been declining, according to Matt Forister, professor of ecology at the University of Nevada, Reno (UNR). Forister highlights that nearly 30 species of mountain butterflies face the same threats that monarch butterflies do, and hopes that people will recognize their importance and rally around them too.

In the U.S. Fish and Wildlife Service’s press release, they highlighted the threats to monarchs as “loss and degradation of breeding, migratory and overwintering habitat; exposure to insecticides; and the effects of climate change.” Forister noted that montane species of butterflies undergo these same issues.

Forister has known about butterflies and other insects since he was a child—his father was an entomologist. And while Forister studied English in college, he eventually returned to ecology and biology because of its scope. Since the early 2000s, entomologists have seen the decline of insects due to pesticides and building development—like in the common sooty-wing (Pholisora catullus), which thrived in weedy lots from Sacramento to Tahoe until chemicals began killing them off. Surprisingly though, at higher elevations, mountain species seemed to be doing just fine.

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“There are almost 400 species of butterflies in the western US and more than a hundred species can be seen in the northern Sierra Nevada including the Tahoe area. And that biodiversity is really amazing,” said Forister. “We hoped, 20 years ago, that the butterflies would be more resilient and adapt to changes in the climate, either by moving up the slopes or by utilizing available microclimates.”

Unfortunately, that was not the case. As climate change sparked the megadroughts of 2011 to 2015 in California, butterflies suffered. Plants, their primary food source and nesting habitats withered as water became scarce. Seasons shifted, the rain and snow coming later and later in the year, disrupting life cycles dependent on weather. And constant heat stress led to an early grave for caterpillars and butterflies alike. While all these factors are important, scientists are still trying to pin down which ones have the largest impacts.

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“Butterflies are really good for the study of ecology because they’re easily observable and they can have some strong indicators for changes in the environment,” said Forister. Because they feed on plants, with life cycles tied so innately to the environment and seasons, changes in their populations can indicate larger ecological changes.

For example, as butterfly populations decline, pollination for plants in the area suffers. And birds, reptiles, and other larger insects that predate on caterpillars and butterflies have less to eat. Forister also emphasized the importance of having healthy insect biodiversity. “All these species do subtly different things. They have different active times which means different predators can have food sources at different times of the year, different proboscis sizes and body shapes which leads them to visit and sometimes pollinate different plants, and importantly, they also have different types of resilience to stressors.”

One of the major findings Forister noted about mountain species is their reliance on the snowpack. “We think that butterflies that spend the winter as eggs are suffering the most in the mountains around us,” said Forister. Not every butterfly migrates like the monarch butterfly—in fact, many in the area spend the winter as eggs and hatch in the springtime. “But when the snowpack is more ephemeral, those caterpillars might be hatching too early” Then, those caterpillars perish when available resources including plants aren’t right.

Migration can still play a role for butterflies in the mountains, though. “That’s something we see in mountain populations of some species, where interestingly, they rely on the movement of individuals from lower elevations each year,” said Forister.

Forister acknowledged the difficulty of tackling conservation from a new angle. “Conservation biology used to focus most on insect species with small geographic ranges, which only lived for example in a small area. You could put up signs or protect those areas. But now, we’re moving to an era of climate change and other challenges facing natural populations where insects and other species are declining across huge swathes of land, and you have to think of new solutions. It’s not enough to simply put up fences.”

But there’s still hope for montane butterflies in your backyard. The number one way to help that Forister suggests is stopping use of pesticides. “You can manage the land you have access to, whether that’s your apartment balcony or a big garden you’ve got in the front yard. Stopping the use of pesticides, especially in cases where it’s just to improve the appearance of a yard is an easy thing I always put first, because it’s something everyone can do.”

Forister also notes that if you have the ability to, planting native plants is another huge help, as it restores the preferred food and habitats of these threatened species.

Lastly, Forister encourages helping out with research through citizen science. “Documenting these butterflies with an app like iNaturalist or other online tools helps scientists understand the ranges of these animals. And butterflies, unlike most other insects, are more easily identified by pictures that people can take with their phones.” Donner Summit is one of the local regions where butterflies have been studied for nearly 150 years.

Some local montane species like the large marble (Euchloe ausonides) have been proposed for legal protections, just like the monarch butterfly. But the fight to preserve these beautiful bugs will continue to need conservation efforts from a local, state, and federal level.