Is Earth on track for a mass extinction? More than 20% of migratory animals are now at risk of being wiped out, report warns
- Report warns human activity is causing overall decline in species that migrate
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From sea turtles to elephants, migratory animals include some of the most iconic species on the planet.
They can travel for thousands of miles depending on the time of year, often to breed, find food, or otherwise simply survive.
Unfortunately, these incredible animals are at risk of being wiped out – and it's humans who are largely to blame.
A new report warns that 22 per cent of the world's migratory species are threatened with extinction and almost half are at least declining in numbers.
The two greatest threats to these animals are overexploitation and habitat loss – both the result of human activity.
The new report names 260 migratory species (22 per cent) as threatened with extinction, including the hawksbill turtle and the addax, a spiral-horned antelope
The new 'State of the World's Migratory Species' report is published today by the Convention on the Conservation of Migratory Species of Wild Animals (CMS).
'Today's report clearly shows us that unsustainable human activities are jeopardizing the future of migratory species,' said Inger Andersen, executive director of the UN Environment Programme.
'Creatures who not only act as indicators of environmental change but play an integral role in maintaining the function and resilience of our planet's complex ecosystems.'
Billions of animals make migratory journeys each year on land, in rivers and oceans, and in the skies.
They cross national boundaries and continents, with some travelling thousands of miles across the globe to feed and breed.
Migratory species play an essential role in maintaining the world's ecosystems, and provide various benefits, such as pollinating plants and transporting nutrients.
The report relied on species datasets and contributions from institutions including BirdLife International, the International Union for Conservation of Nature (IUCN) and the Zoological Society of London (ZSL).
Pictured, sociable lapwing, an endangered migratory bird, which breeds in Kazakhstan and winters in the Middle East, Indian Subcontinent and Sudan
Other endangered migratory species include the European eel, which starts in the Sargasso Sea near Bermuda and takes it across the Atlantic Ocean to Europe and then back again
IUCN publishes its famous Red List, the world's most comprehensive inventory of the global conservation status of biological species.
Out of 1,189 animal species recognised by CMS as needing international protection, 260 species (22 per cent) are considered threatened with extinction, while 44 per cent (520) are showing declines in populations.
The 260 threatened with extinction have been assessed as either 'Critically Endangered' (68), 'Endangered' (78) or 'Vulnerable' (114) on the IUCN Red List.
Among them are the Hawksbill turtle, notable for its narrow, pointed beak and a distinctive pattern of overlapping scales on its shell.
The critically endangered turtle species is found throughout the world's tropical oceans, largely in coral reefs, and has been historically hunted by humans.
It migrates long distances – typically 90 miles (150km) – between foraging areas and nesting beaches.
Also threatened is the scalloped hammerhead shark, which is overfished and prized for its fins by illegal traders.
It's believed the shark species migrates to deeper waters to find food until it reaches full adult size and eventually returns to its original location.
The critically endangered Hawksbills are found mainly throughout the world's tropical oceans, mostly in coral reefs
Conservation scientists consider the scalloped hammerhead (pictured) to be endangered with extinction
In terms of land animals, the list includes the addax, a spiral-horned antelope native to the Sahara Desert.
It's thought to migrate south to Africa's Sahel savanna zone during the hot season in order to meet the first showers and rain-generated pastures.
Other endangered migratory species include the European eel, which starts in the Sargasso Sea near Bermuda and crosses the Atlantic Ocean to Europe and then back again.
There's also the North Atlantic right whale, also hunted to the brink of extinction by the 1890s.
According to the report, human-built obstacles, like bridges and roads, are acting as physical barriers to migration for many of these animals.
This lowers the chances of a successful migration, which in turn lowers the chances of survival.
Even 'non-physical' barriers such as disturbance from industrial development and shipping traffic, represent 'formidable barriers to migratory populations'.
The addax is thought to migrate south to Africa's Sahel savanna zone during the hot season in order to meet the first showers and rain-generated pastures
The North Atlantic right whale (pictured) was hunted to the brink of extinction by the 1890s
Removing or mitigating physical obstacles to an animal's migration, such as roads and bridges, vital in ensuring the survival of migratory species
Out of 1,189 animal species recognised by CMS as needing international protection, 260 species (22 per cent) are considered threatened with extinction
Other factors include pollution, including pesticides, plastics, heavy metals and excess nutrients, as well as underwater noise and light pollution.
In particular, the current situation for fish is of 'particular concern', with a whopping 97 per cent of CMS-listed fish species threatened with extinction.
Researchers say 'coordinated international action' is 'urgently needed' to reverse population declines and preserve these species and their habitats.
'The global community has an opportunity to translate this latest science of the pressures facing migratory species into concrete conservation action,' said Andersen.
'Given the precarious situation of many of these animals, we cannot afford to delay, and must work together to make the recommendations a reality.'