The year is 2024. With the world's population continuously rising, man has looked to the sea for increased food supply and energy resources. Nirai Island - also known as Standard Blue - is the largest artificial island in the world. Near its waters the Ushio Sea Service operates, finding anything from lost pets to salvage quickly and accurately - for a price. Its crew is led by the elderly Taizou and a band of seafaring misfits, plus one new addition: Shiki, Taizou's granddaughter. She has run away from home to help cope with a personal tragedy four years ago, and slowly but surely gets in touch with the sea. Alongside the crew of the Ushio Sea Service, Shiki helps rescue dolphins and save stranded people in distress, but she soon will face her most difficult and dangerous challenge yet...

[Source: Anime-planet]