In the mythology of New Zealand's Maori people, night-time is associated with many terrors. One of those is the bone-chilling call of the Hakawai, a huge mythical bird with startling red, black and white feathers.
Although it is rarely seen, simply hearing it is bad enough – the sound alone has been thought by many to be a bad omen. Not long ago, if a Maori caught that dreadful sound, "hakwai, hakwai, hakwai," quickly followed by a distinctive rushing noise, the hairs on the back of his neck might have stood up straight – and he would have run for his life.
Throughout human history, people have associated all kinds of animals, some real, some mythical, with evil. And there are still many examples of this today.
When ornithologist Colin Miskelly first heard the call of the Hakawai in the mid-1980s while doing fieldwork on New Zealand's Chatham Islands, the hairs on the back of his neck stood up too. But he didn't bolt for it. Miskelly was on a hunt for the Hakawai with a tape recorder in hand. His plan was to capture the sound of the bird and play it to local Maoris to see if they recognised it.
There were many accounts of muttonbirders dropping their birds
Miskelly had been told that people in the area who went muttonbirding – harvesting the chicks of seabirds – had long been familiar with the terrible night-time shriek of the Hakawai.
"There were many accounts of muttonbirders dropping their birds, the dead birds they had been harvesting, and running back to their huts because they were so scared," he recalls.
Whether his recordings sounded like the Hakawai divided opinion among the locals. That may be because Miskelly had not captured the vocalisations of a mythical beast on his tape recorder, rather, the sounds were made by a much less blood-curdling species, the Chatham Island snipe, which is just 20cm long.
The "Hakawai noise" can be heard when the snipe performs a nocturnal aerial display of two parts: a series of undulating vocalisations and then an extraordinary rushing sound that almost defies description.
The Hakawai is not the only ominous bird that appears in Maori legends
"Some people called it the chain bird, they'd liken it to the anchor chain being lowered into the hull of a boat," explains Miskelly. "Others described it as a jet plane flying overhead."
He realised that signs of unusual wear to the snipes' tail feathers revealed how such a humble bird could make such an unusual sound. The birds were diving through the air at high speeds, Miskelly hypothesised, causing their tail feathers to vibrate excessively. Over time, that wore them down.
Not only did Miskelly's investigations offer a possible explanation for old Maori stories about a dreadful bird of the night, his insights improved people's understanding of the Chatham Island snipe itself.
"At the time in the 1980s, you could actually read texts saying the New Zealand birds do not have an aerial display, almost as the opening sentence about what defines New Zealand snipe," he says. "But research has shown, yes they do, it's just they happen to do it in the middle of the night."
The Hakawai is not the only ominous bird that appears in Maori legends. Another mythical bird, called the Poukai, is said to eat humans.
Folklore about such horrors could presumably serve to keep people watchful and safe
It is not entirely clear where these stories come from. Some have wondered whether Maori tales about such creatures ultimately stem from the time of the Haast's eagle – the largest eagle ever to have lived. It became extinct around 1400 but some think it was large enough to attack and eat people.
We should perhaps be thankful these stories exist. Folklore about such horrors could presumably serve to keep people watchful and safe.
On the other hand, animals associated with the night have long been targets of suspicion and hatred in many cultures.
Take the owl in medieval England, it was often characterised in a very negative light. References to this are dotted throughout poetry of the era. In a poem called The Owl and the Nightingale for instance, the nightingale opens her argument against the owl by listing attributes like her sharp beak and shrieking howl. "You fly by night," accuses the nightingale, "you show that you're an evil creature."
Medieval literature and art is full of animal symbolism, says Brigitte Resl of the University of Hull. Nocturnal animals were inherently strange to people in those times.
"In pre-modern periods, nights were something much more scary than they became later on when they could be lit," she explains. "In those periods, the night was just dark."
Our negative ideas about animals might simply be projections of our own vices
Humans found it hard to explain how animals could navigate in such conditions. We now know that this is because of the high number of rod cells in their eyes. The pigment in these cells is very sensitive to low light and is produced at a steady rate at night, allowing these animals to see.
Other attributes could also earn innocent animals a bad reputation, such as the toad. Its sexual activity during mating season may have been frowned upon during the very religious Middle-Ages, Resl suggests: "I haven't found anything positive about toads."
Sometimes, then, our negative ideas about animals might simply be projections of our own vices.
Fortunately, these perceptions can change with time. Owls have also long been associated with wisdom. Negative prejudices about them today are much less common.
Evil animals tend to be associated with behaviours and attributes that humans can find difficult to explain
Margo Demello, an author and animal rights activist, has another surprising example of previously disliked animals – the rabbit and hare. It is hard to think of species that we consider more innocuous than these fluffy creatures, but in 18th Century Sweden, there was a belief that witches might transform themselves into hares, which would suck the milk from their neighbours' cows, draining them dry.
"It seems extraordinary and ridiculous, but there are actual court cases where women were tried and convicted on the spectral testimony of their neighbours," says Demello.
It is not always obvious why such myths develop, but there are clear themes. "Evil" animals tend to be associated with behaviours and attributes that humans can find difficult to explain – and they have also been used as vehicles for commentary on what we see as our own failings.
Today some cultures still have very deeply felt ideas about animals that they say are evil. One powerful example is the wide range of superstitions about the aye-aye, a rare lemur, native to Madagascar. Some locals, including members of the Sakalava ethnic group, believe that the aye-aye is a sign of doom, an embodiment of evil.
The aye-aye does appear slightly grisly. Its hair is wiry, black or grey and it has large, orange eyes. Most distinctive of all, however, is its unusually long and thin middle finger. This is a very useful adaptation – the aye-aye taps on tree trunks and branches with this finger, using echolocation to listen for the sonic reflection of tasty grubs and other prey inside. It can tap as quickly as eight times per second.
Generally speaking, they are thought to be evil spirits
When food is detected, the aye-aye uses its powerful teeth to chew into the log and scoop out a meal with its finger.
In 1990 Lee Durrell, widow of naturalist Gerald Durrell, accompanied her husband on an expedition to Madagascar to look for aye-ayes and, at the request of Madagascar's government, bring some to the island of Jersey for breeding at the Durrell Wildlife Park.
"By that time it was known that aye-ayes were not extinct on the mainland but they were thought to be in very, very few pockets of forest in the east," says Durrell.
Guides at the time explained how local people felt about them – there was no doubt that the animal was deeply unpopular. Although Durrell never saw this herself, it was reported that aye-ayes were sometimes killed on sight by villagers and then hung up for display.
"Generally speaking, they are thought to be evil spirits," says Durrell. Some mistook them for an actual omen of death, for instance. "If it's a small one, it might be a child who will die or if it's a grizzled, old, white-ish grey aye-aye, it'll be an old person that will die."
There were people who did not want the Hakawai to be explained
Aye-ayes are nocturnal, so perhaps they had that counting against them, but they can also cause damage to people's crops.
"The aye-ayes will come into plantings and wreak havoc – people certainly don't like that," says Durrell. "A tiny patch of sugar cane, a few plants really, and an aye-aye will come in and destroy that within a week."
This example reveals another way that an animal can get into our bad books – by doing something to us that we do not approve of.
For the aye-aye these local beliefs could prove devastating as the species is currently listed on the IUCN Red List as endangered. To combat this there are now efforts to teach villagers that it is endangered, such as the Sava Conservation Project run by Duke University.
But changing such convictions is not easy. Even Colin Miskelly heard second-hand reports from Maori people that his investigations into the Hakawai were not welcomed by all.
The world around us is full of unusual creatures
"When I started researching this in the 1980s, there were people who did not want the Hakawai to be explained," he remembers, pointing out that the myth was powerful to them exactly because it was unexplained.
If these fears seem abstract, consider that even Western city-dwellers sometimes shudder at the sight of a bat, or cringe when a black cat crosses their path. Superstitions about animals then, seem quintessentially human and are clearly widespread, with damaging consequences.
"How we think about animals is not abstract," notes Demello, "it plays itself out in reality."
The world around us is full of unusual creatures. As we continue to encroach on their habitat it is only natural that they could, in turn, threaten us or our resources. The more we understand and respect our natural world, the less likely we might be to damage it.
That being said, nature will always be capable of unnerving us. You will know the feeling when you next hear some deathly whooping in the night, making the hairs stand up on the back of your neck.
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