Cod and Haddock Go North Due to Warming UK Seas, as Foreign Fish Arrive

Desdemona Despair

Cod and Haddock Go North Due to Warming UK Seas, as Foreign Fish Arrive – “In a few decades, the temperature of our seas is likely to be roughly the same as those found in the waters around Portugal at the turn of the last century”

By Robin McKie
2 September 2017

(The Observer) – Britain must prepare itself for invasions of growing numbers of foreign sea creatures attracted by our warming waters, a new report has warned. Some newcomers could have devastating effects, others could be beneficial, say the researchers.

Examples provided by the team include slipper limpets that could destroy mussel and oyster beds. By contrast, new arrivals such as the American razor clam and Pacific oyster could become the bases of profitable industries for British fishermen.

The team’s research also stresses that Britons will have to change their ideas about the seafood they eat as favourites will disappear from UK waters. Haddock and cod are being forced polewards as ocean temperatures rise, while flatfish like sole and plaice have nowhere suitable to go. At the same time, cuttlefish and sardines are being caught in rising numbers and are destined to become the fish of the future for Britain.

The latest report, published in Aquatic Conservation: Marine and Freshwater Ecosystems, provides a crystal ball that could highlight which parts of our coastlines will be most vulnerable to climate change triggered by rising atmospheric levels of greenhouse gas emissions produced by cars, factories and power plants. Sea temperatures around Britain have already risen by more than 1.5C in the past 30 years because of these changes, and scientists have warned this trend could continue for much of the rest of the century.

“In a few decades the temperature of our seas is likely to be roughly the same as those found in the waters around Portugal at the turn of the last century – so we can expect to find the kind of marine life that existed there in British seas in the near future,” said marine biologist Professor Stephen Simpson, of Exeter University. “Apart from cuttlefish and sardines – which are already moving into our waters – we can expect fish like red mullet and john dory to be more common. By contrast the haddock is already disappearing from the southern North Sea, while plaice and sole are also becoming less and less prevalent. Fortunately, cod appears to be more resilient.” [more]

Cod and haddock go north due to warming UK seas, as foreign fish arrive

ABSTRACT: 1. Climate change can affect the survival, colonization and establishment of non-native species. Many non-native species common in Europe are spreading northwards as seawater temperatures increase. The similarity of climatic conditions between source and recipient areas is assumed to influence the establishment of such species, however, in a changing climate those conditions are difficult to predict.

2. A risk assessment methodology has been applied to identify non-native species with proven invasive qualities that have not yet arrived in north-west Europe, but which could become problematic in the future. Those species with the highest potential to become established or be problematic have been taken forward, as well as some that may be economically beneficial, for species distribution modelling to determine future potential habitat distributions under projected climate change.

3. In the past, species distribution models have usually made use of low resolution global environmental datasets. Here, to increase the local resolution of the distribution models, downscaled shelf seas climate change model outputs for north-west Europe were nested within global outputs. In this way the distribution model could be trained using the global species presence data including the species’ native locations, and then projected using more comprehensive shelf seas data to understand habitat suitability in a potential recipient area.

4. Distribution modelling found that habitat suitability will generally increase further north for those species with the highest potential to become established or problematic. Most of these are known to be species with potentially serious consequences for conservation. With caution, a small number of species may present an opportunity for the fishing industry or aquaculture. The ability to provide potential future distributions could be valuable in prioritizing species for monitoring or eradication programmes, increasing the chances of identifying problem species early. This is particularly important for vulnerable infrastructure or protected or threatened ecosystems.

Non-native marine species in north-west Europe: Developing an approach to assess future spread using regional downscaled climate projections