Originally published 2019-04-02.
The famous purple-line map that went viral in 2019 shows the routes of 20 young steppe eagles tagged in western Kazakhstan in 2018, each line tracing one bird over roughly ten months. It is not, as many posts claimed, the journey of a single eagle over twenty years. The routes loop south through Russia, Kazakhstan, Iran, Iraq and Saudi Arabia, and they bend around the Caspian Sea and the Red Sea rather than crossing them. That detour is not a mystery: steppe eagles are soaring birds that depend on rising warm air, and warm air rises over land, not over open water.
Here is how the map came to light, what it really shows, and what years of satellite tracking have taught scientists about one of Eurasia's great migrating raptors.
How a dead eagle in Saudi Arabia started it all
The story began in Saudi Arabia, where a man named Fahd Qash came across a dead eagle among rocks. Fixed to its back was a small electronic transmitter with a label asking whoever found it to get in touch by email. Qash posted photos of the bird and the device in Arabic. A friend contacted the American wildlife biologist Todd Katzner, whose team had fitted the tracker, and Katzner replied with an image of the migration routes of all the birds in the study.
The eagle as it was found, and the tag on its back. The bird is a steppe eagle (Aquila nipalensis), one of the larger eagles of Eurasia, with a wingspan that can reach well over two metres in the biggest individuals. Transmitters like this one sit on the bird's back, held by a light harness, and report the eagle's position to researchers via satellite.
The finder holding the transmitter, and a close-up of its label with a contact address and serial number. Tags like this exist precisely so that anyone who recovers a bird can tell researchers what happened, which helps them understand where and why eagles die.
As the post spread and was translated, a mistake crept in. Versions on Facebook claimed the map showed one eagle's travels across twenty years. The Russian ornithologist Elena Schneider, who took part in the study, corrected this in a Facebook post on 4 March 2019: the map shows 20 tagged juveniles, and, as she pointed out, GPS tracking at this level of detail did not even exist twenty years earlier. The fact-checking site Fact Crescendo later confirmed her account.
What the map actually shows
Each purple line is one young eagle tracked by satellite after leaving its breeding grounds in western Kazakhstan in 2018. The lines run down both sides of the Caspian Sea, through Iran and Iraq, into Saudi Arabia and as far as Yemen and the Horn of Africa. Katzner told reporters that some of the birds died in Arabia or Africa, while others went on towards Asia. For young raptors on their first migration, losses like this are sadly normal.
A steppe eagle up close. In the breeding season these birds hunt mainly ground squirrels and other small burrowing mammals on the open steppes of Russia, Kazakhstan, Mongolia and China. In winter they are far less picky and will feed on insect swarms, carrion and even rubbish dumps.
Why the eagles avoid crossing the sea
The most talked-about feature of the map is that the eagles go around large bodies of water instead of over them. There is a well-understood reason. Eagles, vultures, buzzards and storks are soaring migrants. Instead of flapping all the way, they climb in thermals, columns of warm air that form when the sun heats the ground, and then glide long distances before finding the next thermal.
Thermals form over land, not over the sea, and large soaring birds cannot keep up powered, flapping flight for long. A wide stretch of water is therefore a real obstacle. That is why soaring migrants gather at narrow crossings and land bridges: the Strait of Gibraltar, the Bosphorus, Eilat in Israel, Suez, and Bab-el-Mandeb at the southern tip of the Red Sea. For steppe eagles heading to Africa, autumn passage is concentrated at Bab-el-Mandeb and spring passage at Suez. The map shows exactly this behaviour.
Readers online came up with their own theories, some sharp and some just for fun.
A reader guessed the eagle could not see the far shore of the Red Sea; another correctly pointed out that birds do not get rising warm air over water. The second answer is the one ornithologists would give.
A joke about a "Nokia brick" transmitter with a twenty-year battery, playing on the false claim that the map covered two decades. As Elena Schneider noted, satellite tracking at this level of detail did not exist twenty years before the study.
Some readers were simply sad about the dead bird, while others answered with a Monty Python "pining for the fjords" joke and a nod to the imagined twenty-year journey.
A tongue-in-cheek comment suggesting the eagle avoided Iran for political reasons. In fact, several of the tracked birds flew straight through Iran, as the map clearly shows.
Another reader wondered whether the bird had avoided Pakistan. The study was run by American and Russian scientists working in Kazakhstan, not by Pakistani parks, which shows how quickly details get scrambled when a picture goes viral.
What earlier satellite tracking revealed
The 2018 study was not the first to follow steppe eagles from space. A paper in the journal British Birds, titled "Steppe Eagle migration strategies – revealed by satellite telemetry", reported on 16 steppe eagles fitted with transmitters, fifteen of them in Saudi Arabia and one in South Africa. The researchers received 3,734 location fixes. (British Birds is the journal that published the work, not the name of the research team, as some write-ups suggested.)
Some of the findings are striking:
- Long days in the air. The longest mean daily flight distance among the tracked birds was about 355 km.
- Epic journeys. One adult took almost eight weeks to fly 9,543 km from Botswana to Kazakhstan, about 177 km a day.
- A year split three ways. One adult male followed for a full year in 1998 spent 31.5% of it in its wintering area in Ethiopia and Sudan, 41.9% on its breeding grounds in Kazakhstan, and 26.6% on migration.
- Young birds take it slow. Immature eagles stayed on their wintering grounds much longer than adults, typically about six months, and returned north later, in mid-May rather than late March or early April.
Put simply, a steppe eagle spends roughly a quarter of its life travelling, and much of that time is spent following land routes that keep it close to the thermals it needs.
Why this tracking matters: an endangered eagle
The steppe eagle is not just a curiosity. It is listed as Endangered on the IUCN Red List, and its population is thought to have fallen by well over half. The main threats include electrocution on badly designed power lines, especially in Kazakhstan, steppe fires, nests trampled by livestock, and persecution. Tracking studies show researchers where birds die, which routes they share, and which stopover sites need protecting, information that is almost impossible to gather any other way.
That is also why the label on the transmitter matters. If you ever find a bird with a ring or a tag, note where and when you found it, photograph the tag, and contact the address printed on it or a local bird conservation group. A single message, like the one from Saudi Arabia, can fill in a gap in a scientific dataset and, as this story shows, spark the curiosity of millions.
Sources: Photos first shared by Fahd Qash and reposted via Faifa Online and Pikabu; reader comments from the original viral thread; Fact Crescendo: This map shows tracking of 20 eagles over a ten-month period; British Birds: Steppe Eagle migration strategies – revealed by satellite telemetry; Wikipedia: Steppe eagle; Wikipedia: Bird migration.
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