The word ‘Hurricane’ puts everyone on alert and the next thing we know we are preparing for it indoors or leaving town. Well, the birds react just like us. They either stay and prepare for it or leave the place and migrate.
Life has beautiful phenomenons and the beauty of nature is that the birds come to know before time regarding the coming of a hurricane and begin their preparation.
So what exactly do the birds do during a hurricane? Are they not susceptible and vulnerable against the high-speed cyclones? Let us delve into the awesome world of birds to understand what they do during a hurricane.
Firstly, hurricanes are big-time storms that swirl with winds of 120+ km per hour.
Hurricanes form in the oceans and move towards land. They bring ocean water on land apart from rain, thunder, and high winds. Hurricanes are known as cyclones in the Indian Ocean and typhoons in the northwest Pacific.
There are three to four techniques that the birds follow.
Let us go through them.
Leave the Area in Advance of an Approaching Hurricane
Birds are quite sensitive to the barometric pressure of the atmosphere and can understand infrasounds.
As soon as the birds sense the information, they start engaging in a feeding spree eating voraciously before the onset of the storm. The birds try to get food while they can and make themselves healthy to prepare for the tough onwards journey ahead.
Some migratory birds like white-throated sparrows migrate sooner than their usual time when they sense a drop in barometric pressure.
Gulls, terns, and other coastal species fly inland. Some of them take advantage of the strong winds on the forefront of the storm to abandon the area and fly away.
Some birds fly towards a storm and successfully detour around the storm to the other side, using the storm as a tailwind to fly away from it. In other words, the birds use storms to push them faster. The birds also used the updrafts to help them carry higher with less effort on their part.
A good example is a bar-headed goose that successfully times its early migration flight to the breeding grounds in sync with the updrafts. This enables it to fly over 27,825 feet over the Himalayas successfully.
Fly into or Through the Storm
In 2017 when hurricane IRMA approached the Atlantic coast of the United States, Bradley Wilkinson had GPS trackers on 18 pelicans and found that some of them weathered the storm by staying close to their ground while other pelicans moved behind barrier islands to hide and avoid the storm.
Certain birds like whimbrels flew into hurricane Irene. She had a satellite tracker that was initially put on her to watch her progress as she migrated from Canada to winter in South America.
Another satellite act whimbrel also flew into the tropical storm and successfully emerged from the middle of the storm. She was however pushed by the strong tailwinds and returned to her original starting point.
The dangers of flying into or being caught in the storm are very much real as the bird species can get trapped inside the hurricane for many days without food and the constant movement can exhaust the birds.
The migrating birds can also be thrown many kilometers away to places where they are not usually found and the lack of fresh water and food can kill the birds.
There have been many cases of American birds ending up in Europe and the offshore and Caribbean birds ending up inland in Massachusetts.
An example being Hurricane sandy in 2012 when brown pelicans and bridled terns and other sea birds were brought to Massachusetts which is more than a thousand miles from the coast!
During the time of Hurricane Sandy, Northern lapwings that are native to Scandinavia and migrate to the African coast for winters were found in North America while Pelicans were swept from Florida to New England.
Pelagic birds and ocean-faring fowls fly into the eye of the hurricane- the calm area in between and move with it while waiting for the storm to be over. This way they get dispersed thousands of miles.
They enter the edge of the spiral hurricane and work their way inwards. Once they are in the eye, there is calmness and serenity. However, they get trapped within the eye till the hurricane gets dissipated and are forced to fly without food or rest.
The North American chimney swifts traveled in the eye of hurricane Wilma and were deposited seven hundred miles in Western Europe in 2005.
Stay Back and Take Shelter
Many birds that do not migrate stay back and prepare just like us for the hurricane. This is especially true for birds that have dependent chicks or eggs.
The birds seek refuge in thick bushes and strong trees. Thick bushes and sturdy trees keep them dry and provide good protection from strong winds.
As it is the bird’s nature to perch on a branch while sleeping, holding on to the branch is not difficult for them. A bird’s anatomy gives them strong leg muscles for a good and strong talon clutch. This way they do not need to exert any pressure while holding on to the trees.
When the leg is bent, the tendons stretch and the toes tighten around the branch. Even if the branch sways, they will sway along but the grip does not loosen. The birds will need to make an effort to unclench their toes if they want to disentangle from the branch.
Birds find cover wherever they feel safe. It can be in man-made houses, tunnels, underneath bridges, and even taxis. During Hurricane Harvey, an injured Cooper’s hawk took refuge in a taxi in Houston.
Parrots and woodpeckers seek shelter in nest holes made in trees or other cavities. This method makes these birds very much at risk (trees can get uprooted and floodwaters entering the cavity).
Burrowing owls and similar species usually burrow into the ground. However, when the hurricane is due, they just go near a thick and sheltered space till the storm is over. Some examples are behind thick hedges, alcoves that are protected, building awnings, and any place sturdy and thick.
After the storm, you will observe many owls returning to their burrows and clearing debris.
Hummingbirds are unique and tend to survive hurricanes and storms due to their small size. They end up taking shelter in the most unlikely places of the hedge, building, etc. Due to their good metabolic rate, they eat a lot even during the hurricane while they can find food.
Sedentary Species of Birds May End up Dying
Researchers have found a strong correlation between injured sedentary bird species in Caribbean islands and the number of tropical storms. (https://peerj.com/articles/3287.pdf)
It strongly points to a correlation between annual death rates and storms suggesting a good mortality rate in sea birds due to the occurrence of hurricanes.
Hurricane Wilma decreased the chimney swifts population by half.
Puerto Rican parrots were driven to the point of extinction with just 22 parrots remaining after Hurricane Hugo in 1989.
Another critically endangered songbird ‘Toxostoma guttatum’, was hit by double hurricanes ‘Emily’ and ‘Wilma’ in 2005, after which this species has not been found.
Birds caught in the eye of the storm also become exhausted and can get injured while entering or exiting a hurricane. Exhaustion and injury can also kill the birds.
Flooding destroys their habitat which again forces them to fly away and seek food. Those birds that become weak and injured die due to lack of food after the hurricane.
How do the birds navigate back?
Birds have a tracking feature in their beaks that is unique to them. They have magnetite (iron oxide) receptors on the beaks.
These receptors keep the birds on the right path when they fly. This avian ‘map’ mechanism is irrespective of hurricanes. It also works when the birds migrate and return helping them to determine their course.
Iron-rich structures most likely mediate information on some magnetic intensity to the birds. The receptors on the beaks, in turn, pass the information to the brain by the ophthalmic and trigeminal nerve and help the birds fly in a particular direction.
This navigational map helps homing pigeons within their land as well as migrant birds to and from their breeding grounds.
To put it simply, if the bird gets blown away to a far distant place by a hurricane, the built-in GPS in its beak enables them to find their way back.
Birds have been prepping up for storms for thousands of years and some live in areas with yearly hurricanes.
They sense the change in barometric pressure and arrival of hurricanes and develop different strategies just like humans. Whether or not they migrate, they start eating voraciously.
Some birds stay back especially those with dependant chicks and eggs and seek shelter together as a family.
Some fly into the storm and take refuge in its eye. Some take advantage of the winds and take a detour around the hurricane using it as a strong tailwind. And some unfortunate ones get blown away or drown due to flooding and uprooting of trees.
In the end, the birds do the best they can and hope to survive the most storms and hurricanes in their lifetimes.
Other articles you may also like: