PORTLAND, Maine — Maine lobstermen are hauling in soft-shell lobsters earlier than usual this year in what some say is a result of a mild winter and ocean warming trends.

Soft-shell lobsters usually don’t start showing up in lobster traps until June or early July.

Their early appearance this year could have an economic impact on Maine’s iconic fishery as soft-shells tend to fetch less per pound than hard-shell lobsters because they have less meat. The upside is that their meat tends to be sweeter.

Local retailers started splitting prices — paying lower for soft shells and higher for hard shells — in late April and early May, which is also much earlier than normal.

The lobster fishery is a billion-dollar industry in Maine.