Marine species are edging closer to Earth’s poles at an average pace of 3.7 miles per year as climate change causes global sea temperatures to rise
- Experts reviewed 258 studies into shifting habitat ranges with climate change
- They used this to make a database, BioShifts, that covers some 12,000 species
- Marine species are moving poleward six times faster than their land-based peers
- This could ultimately see many animals run out of viable habitats in the future
Marine species are edging closer to Earth’s poles at an average pace of 3.7 miles per year as climate change causes global ocean temperatures to rise, a study has found.
It has long been known that the impact of global warming has been forcing animals to leave their normal habitats behind as their environmental conditions change.
However, analysis by French researchers have revealed that marine species are migrating northward around six times faster than their land-based counterparts.
Experts warn that these migrations could see species riding an ‘escalator to extinction’ as their viable habitat ranges grow more and more limited.
Marine species are edging closer to Earth’s poles at an average pace of 3.7 miles per year as climate change causes global ocean temperatures to rise, a study has found (stock image)
In their study, Jonathan Lenoir of the Université de Picardie Jules Verne in France and colleagues reviewed 258 existing studies, comparing more than 30,000 habitat shifts from more than 12,000 species of animals, bacteria, fungi and plants.
They used this information to create a database of climate-driven species movements — a resource which they have dubbed ‘BioShifts’.
The researchers found that terrestrial — or land-dwelling — animals are also moving polewards as the climate warms — but ‘at a pace that is much slower than expected, especially in areas with warm climates.’
The team found that amphibians are moving towards higher latitudes at a rate of around 39.7 feet (12 metres) a year — with reptiles moving their habitats at the slower rate of around 21.3 (6.5 metres) on an annual basis.
Insects, meanwhile — which can serve as a vector for many diseases — were found to be headed poleward at a rate of around 11.5 miles (18.5 kilometres) per year.
Overall, the researchers found that marine species were migrating their habits at an average pace of around 3.72 (6 kilometres) a year — compared to the comparatively slower pace of 5.9 feet (1.8 metres) each year for land-based species.
The team found that amphibians are moving towards higher latitudes at a rate of around 39.7 feet (12 metres) a year — with reptiles moving their habitats at the slower rate of around 21.3 (6.5 metres) on an annual basis. Insects, pictured — which can serve as a vector for many diseases — were found to be headed poleward at a rate of around 11.5 miles per year
According to Dr Lenoir and colleagues, various factors could explain these discrepancies — from how water conducts heat 25 times more effectively than the air, to how land animals are typically better at regulating their body temperature.
This means that marine species are likely more motivated to shift their habitat ranges — and also more capable of doing so than their terrestrial counterparts, who may be impeded by human activities, which may force movements in the ‘wrong’ direction.
‘On land, habitat loss and fragmentation due to land use changes may impede the ability of terrestrial species to track shifting isotherms [lines of constant temperature],’ the researchers wrote in their paper.
‘These complex interactions need to be accounted for to improve scenarios of biodiversity redistribution and its consequences on human well-being under future climate change.’
The researchers have cautioned, however, that — despite its size — the BioShifts database is limited by only covering around 0.6 per cent of the known life on Earth, and has an inherent bias towards those species that live in the northern hemisphere.
Nevertheless, the database may still help experts track habitat shifts — with the potential to help us predict what changes we might face in the future.
The full findings of the study were published in the journal Nature Ecology & Evolution.
EXTINCTION LOOMS FOR MORE THAN ONE MILLION SPECIES
Nature is in more trouble now than at any time in human history with extinction looming over one million species of plants and animals, experts say.
That’s the key finding of the United Nations’ (UN) first comprehensive report on biodiversity – the variety of plant and animal life in the world or in a particular habitat.
The report – published on May 6, 2019 – says species are being lost at a rate tens or hundreds of times faster than in the past.
Many of the worst effects can be prevented by changing the way we grow food, produce energy, deal with climate change and dispose of waste, the report said.
The report’s 39-page summary highlighted five ways people are reducing biodiversity:
– Turning forests, grasslands and other areas into farms, cities and other developments. The habitat loss leaves plants and animals homeless. About three-quarters of Earth’s land, two-thirds of its oceans and 85% of crucial wetlands have been severely altered or lost, making it harder for species to survive, the report said.
– Overfishing the world’s oceans. A third of the world’s fish stocks are overfished.
– Permitting climate change from the burning of fossil fuels to make it too hot, wet or dry for some species to survive. Almost half of the world’s land mammals – not including bats – and nearly a quarter of the birds have already had their habitats hit hard by global warming.
– Polluting land and water. Every year, 300 to 400 million tons of heavy metals, solvents and toxic sludge are dumped into the world’s waters.
– Allowing invasive species to crowd out native plants and animals. The number of invasive alien species per country has risen 70 per cent since 1970, with one species of bacteria threatening nearly 400 amphibian species.