Here's how extreme weather is affecting animal migration

Many species of animals migrate as different seasons come and go, often undertaking long and arduous journeys to other parts of the planet that will offer them a more suitable environment.

But as Earth continues to heat up, widespread changes to weather patterns and shifting seasons are having an impact on animal migration.

With global average temperatures soaring to a new record in September 2023 by 'a huge margin', it's no surprise that increasing numbers of species – including non-migratory ones – are leaving their habitats for cooler, more agreeable environments.

In fact, around half of all species are on the move – from moose and bears to frogs and squirrels – according to researchers at the University of Southern California (USC).

Where are they going? Largely speaking, further north and to higher ground. But different species migrate at different speeds because of biological and environmental factors, the USC researchers explain.

It’s this “dispersal rate” that will ultimately determine a species’ fate – whether they can get to where they need to be within increasingly shifting timelines.

The data on this has been incorporated into a new computer modelling tool, the MegaSDM, which is helping to provide more accurate mapping of animal movements and identification of those at most risk of extinction.

One animal it is tracking is the pika, an alpine mammal closely related to the rabbit, which can overheat in temperatures as mild as 25.6°C, according to the USC. Its migration patterns are likely to change as temperatures rise in its traditional habitats.

Here’s how the climate crisis is affecting the migration movements of several other species around the world.

“Elephants know no boundaries – they are moving in search of food and water.”

This was how Tinashe Farawo, spokesman for the Zimbabwe Parks and Wildlife Management Authority, explained the recent movement of many elephants from Zimbabwe to Botswana, as reported by The Guardian.

Overpopulation in some national parks and lack of rainfall are cited as the main reasons behind this change in elephant behaviour.

The UK’s wild bird population has been falling since the 1970s, with half of all species in decline as a result of biodiversity loss, pesticide use and other pressures, reports the BBC.

Extreme weather is creating major pressure for migratory birds, according to the British Trust for Ornithology. This includes cuckoos, which tend to leave Britain in June for Africa, but are now often struggling to make it back over the Sahara due to lack of food, the BBC says.

Changing environmental conditions are also enabling British species like the Cetti’s warbler to spend more time in Europe, and for non-native bird species such as the European bee-eater to set up home in the UK.

A population of mule deer in the American West has sparked greater hope of animals being able to adapt as climate change continues “messing with nature’s alarm clocks”, new research shows.

In the Wyoming desert, springtime signals to migrate can be inconsistent, reports the US Geological Survey. Yet each year the deer continue travelling to higher elevations – taking advantage of abundant foodstuff en route – and are reaching their destination within an average six-day window, researchers say.

How? By naturally adjusting their timing, either speeding up or slowing down during the journey.

The only way to ensure a healthy existence for animals – and humans – on the planet is to drastically reduce the damage we are inflicting upon it.

Half of the world's top ten global risks in the next two years are environmental, as the World Economic Forum highlights in its 2023 Global Risks Report, with biodiversity loss and ecosystem collapse one of the most significant threats over the next decade.

Progress is being made, such as the landmark deal to protect nature agreed at the COP15 UN Biodiversity Conference last year. It promises to protect 30% of the Earth’s nature by 2030

But more needs to be done to reverse rises in global temperatures. The International Energy Agency (IEA) says “almost all countries need to bring forward their targeted net zero dates” – although it also sees some hope for a more sustainable future given the extraordinary rise of clean energy.

“The pathway to 1.5°C has narrowed in the past two years, but clean energy technologies are keeping it open,” IEA Executive Director Fatih Birol says. “With international momentum building behind key global targets such as tripling renewable capacity and doubling energy efficiency by 2030 … the COP28 climate summit in Dubai is a vital opportunity to commit to stronger ambition and implementation in the remaining years of this critical decade.”