Conservation groups have sued the National Marine Fisheries Service for loosening regulations on Hawaii-based longline swordfish fishers that are designed to protect sea turtles.

The environmental law firm Earthjustice said the lawsuit filed Wednesday in federal court challenges the rule change to allow the fishery to accidentally capture a maximum of 46 threatened loggerhead sea turtles each year. That is up from 17.

Earthjustice says the new rule conflicts with the agency's own assessment that the turtle is in danger of extinction.

The fisheries service said when it issued the rule Dec. 10 that it optimizes the U.S. harvest of swordfish and other fish species, without jeopardizing the continued existence and recovery of threatened and endangered sea turtles.