BATON ROUGE (AP) — Speakers at a coastal conference say the mouth of the Mississippi River is moving north, and authorities need to prepare for it.

Paul Kemp, vice president of the Louisiana Audubon Society’s Gulf Coast Initiative, says the changes present opportunities to get more sediment into eroding coastal marshes, and to make navigation channels in the river more stable.

The state and U.S. Army Corps of Engineers are studying ways to do that.

Kemp was among speakers at a conference Friday and Saturday about delta restoration.

He showed aerial photos from floods in 1985 and 2011. He said the sediment plume from last year’s flood flowed out of the channel about 15 miles upstream from where it did in 1985.