They would become the most commonly seen species to receive federal protection if the proposal is adopted.

Federal wildlife officials proposed on Tuesday that monarch butterflies receive protection as a threatened species.

The flashy orange and black butterflies, which flutter forth each year on an epic migration that spans thousands of miles and multiple generations, are found from coast to coast in the United States during warmer months. Despite precipitous declines, they are still prevalent enough that, if the proposal goes through, they would become the most commonly seen species to receive federal protection.

That means officials are walking a tightrope with the proposal. Restrict too few activities that harm monarchs, and officials risk creating a merely symbolic listing that does little to stave off further declines. Restrict too many, and they could trigger a political backlash.

Tight rules could also backfire by dissuading people from creating butterfly habitat on their property, because the

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