PORTLAND, Maine — Top lobster scientists are meeting to look at fundamental changes that have affected lobsters in recent years after a summer that featured a potentially ­record-breaking haul in Maine and Canada and a crash in wholesale prices.

The Maine Sea Grant program at the University of Maine is hosting a conference in Portland beginning Tuesday focusing on issues such as warming ocean temperatures, the changing food web, and seafood economics. About 135 people have registered, including scientists from the United States, Canada, and Europe; regulators; and industry representatives.