Long before the invention of wireless networks, carrier pigeons were widely used to send messages. We shed light on how these amazing birds performed this important function in eras when the smartphone did not exist.
What are carrier pigeons?
Carrier pigeons (Columba livia domestica) are also commonly known as homing pigeons because of their instinctive ability to find its way home after being released elsewhere. This ability also enables them to be used in the sport of pigeon racing. They are a domesticated breed of rock pigeon that is often confused with the closely related but very different passenger pigeon (Ectopistes migratorius) of North America, the last of which died in 1914.
Appearance-wise, carrier pigeons have grey heads and bodies covered in black, grey and white feathers. The neck area is typically covered with irisdescent purplish and green feathers. Besides having red, gold or orange irises, they often have red feet and grey beaks.
How do the pigeons find their way?
Pigeons are able to find their way back to places they have mentally marked as their homes. Pigeon mail works only when the sender is using the receivers pigeon, which will be able bring a message to where its home and the receiver are. This presents an inherent challenge: They have to be transported to release sites before they can be used to send messages home.
Besides visual cues such as natural landmarks, various studies have proposed that geomagnetic features, either individually or in combination, can help animals determine their location relative to a goal, serve as landmarks or as triggers for location-dependent behaviours like changes in physiology and direction. Researchers such as Viguier (1882) and Walcott & Green (1974) found evidence that pigeons are highly responsive to spatial and temporal variations in geomagnetic parameters. This particularly strong magnetoreception means carrier pigeons can use the changes they detect in the Earths magnetic field to determine their locations.
According to a study published in 2007, University of Auckland researchers who studied the flight paths of carrier pigeons
homing from sites in and around a magnetic anomaly found strong evidence that the birds detect and respond to spatial variation in the Earths magnetic field. This finding suggests that carrier pigeons potentially use this information for navigation. It has also been found that, because the Earths magnetic field is strongest at the north and south poles, they cover long distances in the north-south direction more successfully than in the eastwest direction.
However, it is not guaranteed that these aerial messengers will always reach their intended destinations. Researchers of the same 2007 study reported that the tendency for pigeons to align their flight direction with the geomagnetic field may explain how magnetic anomalies and storms disrupt the initial orientation of pigeons homing from unfamiliar release sites. In 2013, in the Journal of Experimental Biology, geophysicist Jon Hagstrum proposed that carrier pigeons follow ultra-low frquency sounds (known as infrasound) back to their lofts and impediments to this ability prevent them from homing succesfully. Predators and hunters also pose as obstacles. During World War I, civilians were ordered to shoot pigeons in German occupied territories to reduce the presence of enemy birds.
Pigeons are known to be able to fly at altitudes of 6000 feet or more and as fast as some cars at 60 to 75 miles per hour. Their highest recorded flying speed is 92.5 mph. They can fly between 600 and 700 miles a day.
Unlikely War Heroes
Carrier pigeons were commonly used as messengers during wars. Cher Ami is among the honoured war pigeons. One of 600 birds owned and flown by the U.S. Army Signal Corps in France during World War I, the black check cock carrier pigeon delivered 12 important messages within the American sector at Verdun, France. On its last mission, it managed to return to its loft with a message dangling from the ligaments of its shattered leg after being hit by enemy fire in the leg and chest. That message from Major Whittleseys Lost Battalion of the 77th Infantry Division, which had been isolated from other American forces, saved 194 surviving members of the batallion hours after its reciept.
Cher Ami was awarded the French Croix de Guerre and died in 1919 as a result of its battle wounds. It was later inducted into the Racing Pigeon Hall of Fame in 1931 and received a gold medal from the Organized Bodies of American Racing Pigeon Fanciers in recognition of his extraordinary service. Cher Ami is on display at the National Museum of American History, Behring Center, in the exhibition The Price of Freedom: Americans at War.
At the entrance of Lille Zoo in France stands a statue erected by the Fédération Nationale des Sociétés Colombophiles in 1936 to commemorate the 20,000 pigeons that served and died as well as pigeon fanciers executed for their involvement during the Battle of Verdun, the longest battle of the First World War. Awarded the Ordre de la Nation, Valiant was among these pigeons. It delivered a message to bring reinforcements to the French troops despite being gassed and badly injured. Allied forces continued to use pigeon mail in World War II and the UK military alone deployed some 250,000 pigeons to communicate with those behind enemy lines. ag
Pigeon mail works only when the sender is using the receivers pigeon, which will be able bring a message to where its home and the receiver are.