LAUSR

Climate change is leading to large‐scale shifts in species’ range limits. Mangroves, for example, are encroaching into saltmarshes at numerous tropical–temperate transition zones. However, mangrove expansion varies geographically, in large part because mangroves might not be fully occupying their fundamental niches across their range limits. Here we characterize and compare the fundamental versus realized thermal niches of two mangrove species found near their northern range limits on both coasts of North America.