Amazing Facts About Wildlife

Whales strain their ears to see

Whales and the acoustic squint
Whales strain their ears to see

How whales use SONAR to locate prey in total darkness has fallen to research, says S.Ananthanarayanan.

Toothed whales, which include dolphins, are able to precisely locate and snap up very small fish or other food that come before them, even in deep water where there is hardly any visibility. They use SONAR, or echolocation, of course, but how they achieve the uncanny accuracy has not been understood. Laura Kloepper from the University of Hawaii, USA, and her PhD adviser, Paul Nachtigall now report in the Journal of Experimental Biology, their finding that dolphin species called the false killer whale (because of its resemblance) is able to focus and adjust its beam of sound waves, to get the most crisp echoes and the best fix on its target.

Dolphin apparatus

The dolphin creates high pitched, ie, ultrasonic, ‘clicks’, for echolocation from nasal structures in a region called the melon, in its forehead. The sound is emitted by structures of fatty tissue, called monkey lips, which are made to slap together by forcing air from the lungs – to create the echolocation pulses of sound. The sound waves pass through fatty material in the melon, which minimizes reflection at the contact with water, so that the sound waves pass into the water with the least loss of energy. The rear portion of the melon is hard bone and is concave, to focus, or direct the sound waves in a beam, like a searchlight.

It has been known that toothed whales (unlike baleen whales, which filter seawater through their teeth to capture prey) are able to adapt the frequency and the intensity of the sound clicks, according to changes in the environment. Beams of sound waves, or even RADAR beams, become narrower when the radiation is of higher frequency. It was thought that variations in beam width of toothed whale sounds may be related to the frequency alone. But the bony rear surface of the melon is covered with air spaces, whose pressure and size are variable and do change during emission of clicks, and these could act to focus the beam independent of frequency. The fatty material that fills the melon could also behave like a lens to widen or narrow the beam. The array of muscles and tendons that surround the melon strongly suggest that this is the case, although actual changes in the echolocation beam, according to need, had not been demonstrated.

Experiment

Kloepper and Nachtigal decided to find out with the help of Kina, a trained and well adapted false killer whale that has lives within the Marine Mammal Research Program at the University of Hawaii. The experimental set up consisted of 2 pens, separated by an opening like a hoop. Kina was trained to take position in one pen, with her head inside the hoop up to her first fin, and try to locate a specific object placed in the other pen. Line of sight to the object was blocked by a screen that allowed no light and another screen that was opaque to sound enabled the experiment, with sound waves, to start and stop. Kina was trained to touch a response lever when she spotted the standard target object, or to stay still if she spotted a different object. The standard object was an aluminium cylinder, about 5 inches long and the other objects were similar cylinders, of lesser and even lesser thickness. Kina was rewarded with a fish every time she identified the object correctly, as the standard or different cylinder. An array of underwater microphones also picked up the sounds emitted by Kina and recorded the strength of the sound beam at different points, to estimate how narrow or wide the beam was during each echolocation event. 

The standard object was one that Kina was able to identify comfortably, during trials, while the cylinders of lesser thickness were ‘difficult’ and ‘more difficult’ targets, as revealed in trials. The experiment was then to get Kina to identify the 3 objects, randomly presented at different distances, 2.5, 4 and 7 metres, over the period of some weeks. And during the attempts, to record the frequency and spread of the sound beam that Kina used in the effort.

Discovery

The first look at the results showed that beams of higher frequency were narrower in all cases, which is hardly significant because such narrowing or widening is the property of acoustic beams. But what was significant was that the frequencies were not evenly distributed over different distances and levels of difficulty. Analysis of the beam width at the same frequency and different difficulty levels or at different distances revealed that the changes in beam area did not correlate in all cases to the frequency alone. It was seen that beam areas decreased for difficult targets and increased for greater distances.

The results are consistent with a tendency to concentrate the beam width, so that there is more reflected information, in the case of a difficult target.  Such concentration may be by using a higher frequency, which also leads to better resolution of images. But statistical analysis was able to distinguish the widening that was because of the change of frequency and to identify a positive widening which was not related to frequency, but came about with increasing distance. Although the beam appeared to widen at the array which was placed close to Kina, plotting the path of sound waves revealed that the beams that appeared widest at the array were not spreading out but were focused on farthest targets, while narrow beams aught then to be focused at shorter distances. The results thus showed that Kina was able to adjust both the frequency and the focus of the sound beam so that the maximum energy could be reflected back by the target object, for the best identification.

 
The results reported are a first confirmation that there is actual and constructive focusing of the sound beam by the dolphin. The anatomy of the animal strongly suggests that the action is by varying reflectivity of the concave cavity behind the source of sound, by the action of muscles and the pressure of the air sacs. The young false killer whale then learns to use the ability to resolve morsels that drift across its acoustic viewfinder, much like human babies learn to focus and coordinate their eyes to touch and grasp objects.
[the writer can be contacted at simplescience@gmail.com]


Bird Watching

Birding Expedition at Hauz Khas Lake

Birding Expedition at Hauz Khas Lake

-Prya Phadtare


One rarely manages spot birds in a big bustling city like New Delhi. To satiate my needs of bird-watching I decided to take along my camera and scourge the city for some rarely spotted birds. Hauz Khas happened to be my obvious choice which is situated in the metropolis of South Delhi, built during the rule of the Delhi Sultanate. The complex offers excellent wildlife and bird viewing, which is a rarity in the city.

One needs to walk through the Deer Park, known for its large population of deer, in order to get to the lake. As I walked through the park I could smell the distinctive smell of the lake water and hear the quacking of the ducks, yes ducks! This made me hurry up my walk towards it.

As I entered the arena which houses the lake and the ruins of the Sultanate period I was welcomed by cool breeze, bright sunlight and constant quacking of the ducks. I was dumbfounded to spot at least a congregation of two hundred ducks and along with them a lot of white geese. I immediately checked my Bird-Watchers Handbook to be able to name them exactly.

I keenly observed a group of ducks quacking happily while trying to catch hold of the tadpoles which had gathered around the edge of the lake under the shade of a tree. I noticed that the grey ducks had a distinctive patch of blue and green inside their wings. This helped me recognized them as the Indian Spot-Billed Duck. Its scientific name is Anas poecilorhyncha which is native to tropical and eastern Asia. The duck is mostly found in the southern part of the country but it travels a little northward in the winters as part of its local migration routine. The ducks are medium built with a grey plumage and have brightly yellow coloured bill tips.



I could immediately relate them to a character called Karoo in Japanese manga which is supposed to be the ‘Super-Spot Billed-Duck’.

I walked a little further ahead along the edge of the lake to find white geese! The Snow Geese looked majestice against the backdrop of sparkling water and the black branches of the long dead trees rising out of the water. Some of them decided to come out of the water to eat the grains kept out for them, that’s when I got the opportunity to get closer to them.  The snow geese happen to have two colour plumage morphs, Hauz Khas had the white ones. They are mostly found in the marshy areas and lakes and are not migratory in nature. Their nesting period is in the months of monsoon. My handbook said that they are loud enough to be heard from a mile away!



The Hauz Khas Complex is known to be famous for only its ducks and geese as one often ends up missing out on other bird species like the Red Wattled Lapwing and the Kites. No matter the season or how many times you visit, you will always be able to find exciting new mixes of different bird species, so rest assured that even the most insatiable bird watcher will be satisfied.

I happened to chance upon a beautiful sighting of the Red Wattled Lapwing. Two of those were very majestically perched upon a raft. My handbook gave the scientific name of the birds, which is Vanellus indicus,  and said that they are famous for their loud alarming calls which are mostly interpreted as someone saying did he do it or pity to do it  earning them a colloquial name of the did-he-do-it  birds. The bird has a distinctive trail of black running from its chest to the sides of its crown with its wings being brown and the eyes lined by red. The Lapwings breed in the months of March to August and are infamous for nesting in between the stones of the railway tracks, otherwise they prefer nesting on the trees and live around large open water bodies.


Apart from the birds mentioned above I saw many kites soaring in the sky, unfortunately I couldn’t get close enough to get a good picture to be able to recognize them.
The Hauz Khas Complex promises you many adventures and a lake full of ducks, geese and a lot more. Don’t be shy from entering the ruins as the view offers a grand a picture of the several bird species hopping or swimming from point to the other point of the lake while you read your favourite book. It is a great place to pull out your binoculars, scope and get mesmerized on your walk along the bank of the lake!

Book Reviews

History and Fiction

Book Reviews-Susan Sharma

Book I
Animals and People of the Ottoman Empire (2010) edited by Prof.Suraiya Faroqhi

Throughout the Eurasian continent, power over wild animals since ancient times has been considered a significant attribute of the ruler. This issue has been well studied for many cultures, including ancient Mesopotamia, or, closer to the Ottomans in time, Moghul India. However while in the Ottoman case, palace architecture, pious foundations or the display of precious cloths and furs have been intensively studied so as to elucidate their respective roles in sultanic legitimization, the power of the ruler to control wild animals has not attracted much attention.


Ottoman official sources do not say anything much about the meaning that the sultans and their servitors attached to the display of wild and/or exotic animals. However the 17th-century Ottoman travel writer Evliya Çelebi does offer some clues. When describing a parade apparently held in honor of the campaign of Sultan Murad IV against Iran, he claims that attendants marched ten lions, five leopards and twelve tigers in addition to other wild animals. Particularly the lions were loaded with chains; but just in case one of them broke loose, their keepers carried gazelle meat treated with opium and other somniferous drugs. In case of an accident, the lion, so it was hoped, could be pacified by this food.


The lions were not kept in cages mounted on carts, as seems to have been the case in later periods; this manner of display may indicate that officials intended to strike terror in the hearts of the populace. Thus viewers were not meant to feel a moderate and vicarious titillation, but rather the grip of real fear. Moreover even if Evliya had invented his description, the story would still be of interest, for he was a well-informed observer familiar with Ottoman court practices, and should have known very well what effects the designers of the procession had intended with their display.


But in the end this was a time of festivity; and the feeling of terror was not to get out of hand. Thus Evliya also told us that participants in the parade dressed up as wild animals, and scared the spectators ‘for the mere fun of it.’ Thus the spectators experienced a transition between the ‘real’ and the ‘theatrical’, as the real fear aroused by the chained lions was dissipated by the tame bears and other creatures which amused the spectators at this and other sultanic processions. Apparently it was an essential feature of Ottoman festivals to highlight people on the point of coming to grievous bodily harm, but to stop just short of this eventuality. If a bit of speculation is permitted: this mixture of fear of a wild beast, and of trust in the joyous outcome of the festive encounter may well have enhanced popular trust in the protective powers of the padisah-i alempenah, ‘the refuge of the world’ to whom even wild beasts did obeisance.


Matters are somewhat different in the case of the elephants also often displayed in sultanic processions. If their depiction in eighteenth-century miniatures is any guide, they appeared not as wild beasts, denizens of the jungle, but as animals specially trained to serve their owners. While the Ottomans never took elephants along to war, they emulated this widespread Indian practice, often depicted in Moghul miniatures, by the accoutrements that (artificial) elephants were made to pull in festive processions. In artwork depicting a famous celebration that took place in 1720, we see these animals carrying turrets equipped with mock cannons.  At least in the make-believe world of the festival, the Ottoman sultan had thus augmented his army by the formidable force of a few war elephants.


Moreover India with its numerous wonders both man-made and natural enjoyed a certain prestige in the Ottoman world while on the other hand at least around 1600 there was a more or less explicit competition between the Moghul rulers and the Ottoman sultans. Therefore we can surmise that elephants were paraded in the streets of Istanbul to show that the sultans could rival their Indian counterparts in every conceivable way. If we carry speculation yet a step further, we can also surmise that the Ottoman officials who designed the 1720 procession were out to show that the sultan was not merely the equal of any Indian ruler but in fact the most powerful figure in the Islamic world. This question, and others like it, will need further investigation.


Book II-Fiction
Ladakh Adventure  by Deepak Dalal
 

Vikram and Aditya's adventures, "Ladakh Adventure" is a book targeted at teenagers, I was told.  But when I started reading "Ladakh Adventure", it sustained continued interest, especially since I had visited Ladakh and most places in the book came alive before me.  

Ladakh is the land beyond the Himalayas. On a visit to this remote, majestic outpost of India, Vikram and Aditya camp out on the lofty Changthang Plateau.  Here, they meet a young Tibetan boy named Tsering. But Tsering is unexpectedly abducted and Aditya pulls off a daring rescue. Suddenly Vikram and Aditya are on the run. On the frozen plateau, often referred to as the ‘Roof of the World’, the two friends play a dangerous game of hide-and-seek with a band of mysterious men. Traversing the barren wastes of Ladakh, the story moves to the mountain-city of Leh.

Who is Tsering? Why is he being chased by such fierce resolve? Discover the fascinating secret of Tsering in this fast-moving adventure tale.
‘Ladakh Adventure’ is another enthralling VikramAditya story, set in a wondrous land of startling contrasts and magnificent mountains.

In Deepak's own words
 
"Animals and birds are doubtless the main draw of a forest, but there is more. No forest experience is complete without absorbing the peace and tranquility of a wilderness area. Imagine the absence of the rumble of traffic, of the bustle of humanity, of the drone of engines and motors that run our world. Take in instead the rustle of the wind through the trees, the call of birds and animals, and the serenity of a forest. Understand what primal human beings enjoyed and what cities and civilisation have robbed us of – the grandeur of nature."
 
Order this book online at

http://www.wildscapes.net/product-details.aspx?prdId=42

Calendar of the month

Desktop Calendar April2012

RagooRao from Mysore has done some beautiful digital paintings, which we have converted into monthly calendars.  Please download these calendars free and use them as your desk top wall paper.

By clicking on RagooRao's name, you can read the numerous articles he has written for IndianWildlifeClub.com.  He is also a superb nature photographer.

To download the calendar suitable for the size of your desktop, please click here

Endangered

The last of the big five roaming free in Africa

Conservationists from Ingwe Leopard Research (www.ingweleopard.com) are helping to conserve the last of the infamous ‘big five’ still roaming free in South Africa.

The term ‘big five’ was first used by big game hunters to identify the most dangerous animals to hunt (Lion, Elephant, Rhino, Buffalo and Leopard).  Thankfully it is a term that is now more likely to be associated with tourist safaris and game viewing.

Over the centuries most of the big five were hunted out in all but National Parks and Private Game Reserves. However that is not the case for leopards. They still survive (all be it in dwindling numbers) roaming free, mainly on rural farmland and in remote mountainous areas.


The Ingwe Leopard Research team based near Lydenburg, Mpumalanga are working hard to gather data on the movement and behaviors of these animals and to help to protect the species. As is very common with any conservation project, human conflict is probably the biggest issue they have to deal with. Whether that be from poaching or hunting.

Poachers’ snares account for an unknown number of leopard deaths each year, far in excess of the snares that are discovered. However it is also sadly true that leopard hunting is still prevalent. Livestock owners can still be being granted permits to kill assumed livestock killers. Not only that but CITES enable one hundred and fifty hunting permits to be issued each year to international big game hunters looking for a skin to mount on their wall at home.

Although it is sometimes difficult to set aside the emotional and moral issues around the killing of leopards, there is a need to focus on the practical issues of control and regulation if we are to make any changes. Whilst a ban on all leopard hunting is an ideal that many people would like to see in place, it is a long way off. A phased approach is required such that practical steps can be taken towards that goal.  The first priority must be to gain a better understanding of leopard numbers and behaviors. In this regard, facts can be a better form of ammunition than bullets. This work is in the remote cattle ranches and mountainous regions where most human conflict occurs. It is in these areas where leopards need to be protected from humans, but also farmer’s livelihoods need to be protected from predators.

The leopard sits at the top of the food chain and its very presence is a key indicator of the ecological health of an area and should be celebrated as such.  So what is the future of free roaming leopards? The bottom line is that Ingwe and many other similar research groups need to continue with their work to gather data to help to affect wildlife management policies.

But in the meantime there is good news. There is a reason that leopards have survived so long, when lion, cheetah and other large predators have been hunted out. The leopard is a very adaptable creature. Over the last five years, the Ingwe Leopard Research team has seen how leopards have adapted to changes in their area as land use and human pressure have changed. The team works in sparsely populated areas where they have helped to reduce hunting, with the resultant effect that leopards are becoming more relaxed and can be seen as an asset for tourism rather than hunting. They are helping to establish leopard friendly areas in association with landowners and livestock farmers and within those areas develop pragmatic methods for farmers to live and work in harmony with predators. That requires give and take and ongoing effort on all sides but there is light at the end of the tunnel.

In an effort to help to raise funds for their work, the Ingwe Leopard Research Team has developed a unique African safari for international guests. They believe that tourism and conservation go hand in hand. Each needs the other to succeed. With that in mind, On Track Safaris (www.ontracksafarisuk.com) was formed to not only provide a unique big five safari experience and raise funds for conservation, but also to allow guests to go one step further than the normal safari rhetoric and become involved.

Author: Will Fox

ingweleopard@gmail.com

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