Scientists at Bangor University, working with the Welsh Fishermen's Association Natural Resources Wales and the Welsh Government, have published their findings from what they say is the world's biggest ever fishing impact study.
They chose twelve sites in Cardigan Bay where scallop fishing was halted in 2009.
The sites were fished at different intensities and compared to four areas which were left unfished. The results suggest the area can sustain a certain level of fishing.
The study could open the door for fishing to resume once a sustainable level is decided.
Marine charity Sea Watch Foundation says sightings of bottlenose dolphins in Ceredigion will increase 'week on week', as they return to the shelter of the area to protect their young.
Cardigan Bay is famous for hosting one of Europe's largest semi-resident populations of bottlenose dolphins, one of the area's most important economic assets.
This winter also saw a more unusual visitor, in the shape of the short-beaked common dolphin. This type of species is usually seen in deeper waters such as in nearby Pembrokeshire.
Since it was first recorded, the charity has continued to receive reports from other local observers.
Sea Watch Foundation monitors whales, dolphins and porpoises all over the UK.
Moving pictures of the first new-born bottlenose dolphin calves in Cardigan Bay have been released by the Sea Watch foundation.
Researchers say most births happen in July and August and that the mammals use Cardigan Bay as a safe haven during the summer.
Some will then move to places like the coast of Anglesey.