PORTLAND (AP) – The ferry service that links the islands of Casco Bay to Maine’s largest city plans to raise fares in response to a spike in diesel prices.

Casco Bay Lines Operations Manager Nicholas Mavadones (mah-vuh-DON’-es) says fuel costs have mushroomed, so the ferry service wants to add a 50-cent fuel surcharge on each ticket. Public hearings are scheduled Thursday and Friday to discuss the surcharge, which would take effect on April 20 before the summer tourism season.

Diesel prices have climbed above $4 nationally. AAA says that compares with $2.78 a year ago.

Without the surcharge, Casco Bay Lines projects a $259,000 shortfall.