Cardigan Bay
 

Aberaeron is centrally located on the coast of Cardigan Bay, about halfway between the larger towns of Aberystwyth in the north and Cardigan in the south. The Bay is most famously known for its Dolphins, as it has one of the largest populations of Bottlenose Dolphins anywhere around the British coast. Cardigan Bay is a large section of the Irish Sea, embraced by the west coasts of three Welsh counties, Gwynedd, Ceredigion (Cardiganshire) and Pembrokeshire. It extends from Bardsey Island,  Gwynedd to the north and south to to Strumble Head in Pembrokeshire.

Ocean currents are influenced by the rotation of the earth, with currents in northern hemisphere oceans moving clockwise. This means that water in the North Atlantic originates in the West Indies, and then flows north along the west coast of North America before crossing the Atlantic towards Europe. A major component of this water is the Gulf Stream - warm water from the Gulf of Mexico which travels through the Florida Straits before moving north.
 

The Gulf Stream has a big influence on the climate of Britain and makes it considerably more temperate than it should be at this latitude. It also brings with it a number of species normally found only in warmer waters. These include Leatherback Turtles, Sunfish and Portuguese Man of War Jellyfish, all of which are seen from time to time in Cardigan Bay. The largest turtle ever recorded was found washed up in Cardigan Bay at Harlech in 1988. It was a male Leatherback that drowned after becoming tangled in ropes. It weighed 916kg and measured 2.91 metres in length.

Historically, Cardigan Bay is famous for its Herrings. In 1808 it was reported that the fisherman of New Quay and nearby ports had caught nine million Herring in one night with catches averaging 4,000 to 5,000 fish per boat per night. 

Samuel Lewis wrote about New Quay in his Topographical Dictionary of Wales in 1833 that: 'There are at present from sixty to seventy vessels belonging to this port, averaging from forty to fifty tons' burden each, and employing from one hundred and fifty to two hundred men. Fish of very superior quality is found in abundance on this part of the coast, soles, turbots, and oysters, being taken in great numbers during the season ; a good herring fishery may also be established with advantage.' 

By the 1830's though, the catch had diminished and the fishing boats started to disappear to be replaced by larger boats designed to trade in various cargoes. The demise of the fishing industry at that time however gave birth to the shipbuilding industry for which New Quay, Aberaeron and Aberarth became famous.

As environmental pressures on fisheries and wildlife species increased, it became evident that further conservation measures should be taken in Cardigan Bay. In 1992, the 'Heritage Coast' area was created from New Quay to Tresaith. Since 1996, the sea area adjacent to the Heritage Coast, extending from south of Cardigan to Aberarth just north of Aberaeron, has been designated a Special Area of Conservation under the European Habitats Directive. A number of important species and marine features, were taken into consideration in creating this area. These include:

Bottlenose Dolphins, Tursiops truncatus The Grey Seal, Halichoerus grypus The River Lamprey, Lampetra fluviatilis The Sea Lamprey, Petromyzon marinus Sandbanks slightly covered by sea water all the time Reefs - both rocky and living (Biogenic) reefs. Submerged or partially submerged sea caves

There are now nine organisations with statutory responsibilities for the site, which are working together, as  ‘relevant authorities’ (RAs). Their aim is to establish a scheme of site management for the area.

The Bay is quite shallow, with the 40m depth contour being some 25 miles offshore. As a result, plant life in the form of marine algae can survive on the sea bed over a large area as sufficient light can penetrate to allow photosynthesis. The algae - or seaweeds, as well as the the plentiful plant plankton are, like plants on land at the base of the food chain able to pass on their biomass to the grazers and other animals that make up the complex ecosystem of the Bay.