Seems pretty clear:
Surfboards
150 USD/CAD for travel to all regions (excluding Brazil, Europe, and North Africa)
150 USD, 175 CAD*, or 125 EUR* for travel to/from Europe or North Africa
100 USD for travel to/from Brazil
*CAD amount will be charged exit Canada, and EUR amount will be charged exit Europe.
Additional surfboard restrictions and exceptions are outlined below:
Delta Connection carrier surfboard acceptance and charges may vary. Contact Reservations for more information.
If the surfboard is not in a protective case, you must fill out a limited liability release before the surfboard will be accepted.
Surfboards are allowed up to two (2) boards per bag.
Bags over 70 lbs. will be charged the excess weight fee.
Between Honolulu and Maui, there is a 20 USD/CAD fee.
Boogie boards smaller than or equal to 43 inches (107 cm) will be accepted as part of the regular baggage allowance.
Surfboards over 115 linear inches are not allowed.