Climate Change Impact Threatens Habitats of Migratory Birds, New Study Finds

A flock of blackbirds search for trees to perch on in the town on Hopkinsville, Kentucky February 16, 2013. (Reuters)
A flock of blackbirds search for trees to perch on in the town on Hopkinsville, Kentucky February 16, 2013. (Reuters)
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Climate Change Impact Threatens Habitats of Migratory Birds, New Study Finds

A flock of blackbirds search for trees to perch on in the town on Hopkinsville, Kentucky February 16, 2013. (Reuters)
A flock of blackbirds search for trees to perch on in the town on Hopkinsville, Kentucky February 16, 2013. (Reuters)

The global impact of climate change is threatening the habitats of some migratory birds along their migration route in the eastern Atlantic Ocean, reported the German news agency.

Based on the findings of a recent study, the Joint Wadden Sea Secretariat in Wilhelmshaven announced Monday that the rising sea level in northwestern Europe is one of the main challenges facing migratory birds.

The Wadden Sea off the coasts of Denmark, Germany and the Netherlands is considered the hub of East Atlantic bird migration.

Millions of birds eat up food reserves for their onward flight between Africa and the Arctic in the UNESCO-listed wetland.

“Climate change affects most coastal regions. For example, in addition to sea level rise in the Wadden Sea, extreme weather events such as heavy rain and storms are increasingly affecting the resting and breeding birds,” explained Kristine Meise, program manager for Migration and Biodiversity at the Wadden Sea Secretariat.

“The consequences of climate change, for example the erosion of coasts, are already being felt in the main wintering area off West Africa,” she added.

According to the study, other factors such as overfishing, shipping, and logging have an even greater influence there.

The assessment of habitat’s exertion was part of a study published in late April.

The project has been counting migratory bird populations along the East Atlantic bird migration route every three years since 2014.

The last census in 2020 involved more than 13,000 people in 36 countries.

According to Meise, these regular statistics are of great importance to spot the changing numbers of birds in an early stage, but “the process is difficult because birds normally don’t stay in one place, and sometimes, change their flying routes. This means that one species could be shrinking in the Wadden Sea, but stable or even growing in other parts of the world.”

She noted that counting requires synchronous statistics in all the locations of those birds.

Compared to data from the past decades, the 2020 census shows an increase in the number of 83 migratory groups. The population of birds was stable in 16 percent of these groups, while the researchers recorded a decrease in 30 percent of them, such as the waders that breed in the Siberian Arctic.

Meise suggested the changing climate conditions are the culprit behind those uneven numbers.

“The migratory birds have adapted to schedules over thousands of years. Due to climate change, spring, and thus snowmelt and insects hatching in the Arctic are beginning earlier. This would result in poorer breeding and rearing conditions for young birds, and a lower breeding success.” she said.

To face these threats and preserve migratory birds, the study’s authors have called for protecting the birds’ favorite habitats and applying sustainable preservation measures.



Researchers Document Huge Drop in African Elephants in a Half Century

 Elephants walk at the Amboseli National Park in Kajiado County, Kenya, April 4, 2024. REUTERS/Monicah Mwangi/File Photo
Elephants walk at the Amboseli National Park in Kajiado County, Kenya, April 4, 2024. REUTERS/Monicah Mwangi/File Photo
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Researchers Document Huge Drop in African Elephants in a Half Century

 Elephants walk at the Amboseli National Park in Kajiado County, Kenya, April 4, 2024. REUTERS/Monicah Mwangi/File Photo
Elephants walk at the Amboseli National Park in Kajiado County, Kenya, April 4, 2024. REUTERS/Monicah Mwangi/File Photo

African elephants are Earth's largest land animals, remarkable mammals that are very intelligent and highly social. They also are in peril. Fresh evidence of this comes in a study that documents alarming population declines at numerous sites across the continent over about a half century.

Researchers unveiled on Monday what they called the most comprehensive assessment of the status of the two African elephant species - the savanna elephant and forest elephant - using data on population surveys conducted at 475 sites in 37 countries from 1964 through 2016.

The savanna elephant populations fell by about 70% on average at the surveyed sites and the forest elephant populations dropped by about 90% on average at the surveyed sites, with poaching and habitat loss the main drivers. All told, there was a 77% population decrease on average at the various surveyed sites, spanning both species, Reuters reported.

Elephants vanished at some sites while their populations increased in other places thanks to conservation efforts.

"A lot of the lost populations won't come back, and many low-density populations face continued pressures. We likely will lose more populations going forward," said George Wittemyer, a Colorado State University professor of wildlife conservation and chair of the scientific board of the conservation group Save the Elephants, who helped lead the study published in the journal Proceedings of the National Academy of Sciences.

Poaching typically involves people killing elephants for their tusks, which are sold illegally on an international black market driven mostly by ivory demand in China and other parts of Asia. Agricultural expansion is the top factor in habitat loss.

The forest elephant population is estimated to be about a third that of savanna elephants. Poaching has affected forest elephants disproportionately and has ravaged populations of both species in northern and eastern Africa.

"We have lost a number of elephant populations across many countries, but the northern Sahel region of Africa - for example in Mali, Chad and Nigeria - has been particularly hard hit. High pressure and limited protection have culminated in populations being extirpated," Wittemyer said.

But in southern Africa, elephant populations rose at 42% of the surveyed sites.

"We have seen real success in a number of places across Africa, but particularly in southern Africa, with strong growth in populations in Botswana, Zimbabwe and Namibia. For populations showing positive trends, we have had active stewardship and management by the governments or outside groups that have taken on a management role," Wittemyer said.

The study did not track a continent-wide population tally because the various surveys employed different methodologies over different time frames to estimate local elephant population density, making a unified head count impossible. Instead, it assessed population trends at each of the surveyed sites.

A population estimate by conservationists conducted separately from this study put the two species combined at between 415,000 and 540,000 elephants as of 2016, the last year of the study period. It remains the most recent comprehensive continent-wide estimate.

"The loss of large mammals is a significant ecological issue for Africa and the planet," said conservation ecologist and study co-author Dave Balfour, a research associate in the Centre for African Conservation Ecology at Nelson Mandela University in South Africa.

The world's third extant elephant species, the slightly smaller Asian elephant, faces its own population crisis, with similar factors at play as in Africa.

Of African elephants, Wittemyer said, "While the trends are not good, it is important to recognize the successes we have had and continue to have. Learning how and where we can be successful in conserving elephants is as important as recognizing the severity of the decline they have experienced."

Wittemyer added of these elephants: "Not only one of the most sentient and intelligent species we share the planet with, but also an incredibly important part of ecosystems in Africa that structures the balance between forest and grasslands, serves as a critical disperser of seeds, and is a species on which a multitude of other species depend on for survival."