Cod and chips could soon be off the menu! Popular fish will become less common and harder to catch amid rising sea temperatures caused by climate change, study warns

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It's the go-to meal for a visit to the seaside, but cod and chips could soon be off the menu, according to a new study.

Researchers from Rutgers University have warned that rising sea temperatures will mean fewer popular fish species will be available to catch over the next 200 years.

'While the species we fish today will be there tomorrow, they will not be there in the same abundance,' warned Dr Malin Pinsky, co-author of the study.

It's the go-to meal for a visit to the seaside, but cod and chips could soon be off the menu, according to a new study

In the study, the team set out to understand how warming waters will affect the abundance of popular fish, such as cod.

They suggest that as sea temperatures rise, fish will be forced out of their natural geographic ranges, making it more difficult for fishermen to catch them.

Meanwhile, larger-bodied top predators will stay in their habitats for longer than smaller prey, in part because of the arrival of new food sources to their pre-warming ranges, according to the team. 

'What that suggests from a fisheries perspective is that while the species we fish today will be there tomorrow, they will not be there in the same abundance. In such a context, overfishing becomes easier because the population growth rates are low,' explained Dr Pinsky.

'Warming coupled with food-web dynamics will be like putting marine biodiversity in a blender.'

While previous research has looked at the direct impacts of climate change on individual species, few studies have looked at the wider implications for ocean communities.

In the new study, the team used computer models to assess trophic interactions - the process of one species being nourished at the expense of another.

The models suggest that warming waters because of climate change will cause a huge species reshuffle.

Smaller fish will seek out cooler waters towards the poles, in a 'dramatic reorganisation of life on Earth', according to the team.

Larger predators will stay in place for longer, laying in wait for the next batch of small fish to arrive. 

'The model suggests that over the next 200 years of warming, species are going to continually reshuffle and be in the process of shifting their ranges,' explained Dr E.W Tekwa, who led the study.

'Even after 200 years, marine species will still be lagging behind temperature shifts, and this is particularly true for those at the top of the food web.'

Worryingly, the team suggests that these changes are likely to affect fish around the world.

'These dynamics will not only be in one place but globally,' Dr Pinsky added. 'That does not bode well for marine life, and this is not an effect that has been widely recognized.'

The study comes shortly after researchers revealed that rising sea temperatures are shrinking our favourite commercial fish including cod and haddock in the North Sea and West of Scotland.

The researchers suggest that as sea temperatures rise, fish will be forced out of their natural geographic ranges, making it more difficult for fishermen to catch them (stock image)

Experts from Aberdeen analysed 30 years of trawl survey data on cod, haddock, whiting and saith from the International Council for the Exploration of the Sea.

They found that while juvenile fish in the North Sea and the West of Scotland have been getting bigger faster, the size of adults has been decreasing.

Furthermore, these changes in size are correlated with the increases in bottom sea  temperatures in both areas, the analysis concluded. 

According to the researchers, the data predicts a reduction in commercial fishery yields in the short term — with the long-term forecast presently unclear. 

Fisheries will need to factor temperature changes into their forecasts, the team added, as to mitigate the effects of global warming and maximise sustainable yields.  

SHRINKING SPECIES: EXPERTS PREDICT GLOBAL WARMING WILL CAUSE CREATURES TO SHRINK

A recent study in Canada found that over the last century, the beetles in the region have shrunk.

By looking at eight species of beetle and measuring the animals from past and present they found that some beetles were adapting to a reduced body size.

The data also showed that the larger beetles were shrinking, but the smaller ones were not. 

Around 50 million years ago the Earth warmed by three degrees Celsius (5.4°F) and as a result, animal species at the time shrunk by 14 per cent. 

Another warming event around 55 million years ago - called the Paleocene-Eocene Thermal Maximum (PETM) - warmed the earth by up to eight degrees Celsius (14.4°F).

In this instance, animal species of the time shrunk by up to a third. 

Woolly mammoths were a victim of warming climate, shrinking habitat and increased hunting from a growing early-human population which drove them to extinction - along with many large animals

Shrinking in body size is seen from several global warming events.

With the global temperatures set to continue to rise, it is expected the average size of most animals will decrease. 

As well as global warming, the world has seen a dramatic decrease in the amount of large animals. 

So called 'megafauna' are large animals that go extinct. With long life-spans and relatively small population numbers, they are less able to adapt to rapid change as smaller animals that reproduce more often. 

Often hunted for trophies or for food, large animals like the mastadon, mammoths and the western black rhino, which was declared extinct in 2011, have been hunted to extinction.