Great balls of iron: Researchers uncover clue to bird navigation

Every year millions of birds make heroic migratory journeys across oceans and continents guided by the Earth’s magnetic field. How they detect those magnetic fields has puzzled scientists for decades.

But now a collaboration between the Keays lab at the Institute of Molecular Pathology (IMP) in Vienna and researchers at The University of Western Australia’s Centre for Microscopy, Characterisation and Analysis (CMCA) has added some important pieces to the puzzle.

Their work, published today in the online version of Current Biology, reports the discovery of iron balls in sensory neurons. These neural cells, called hair cells, are found in the ear and are responsible for detecting sound and gravity. Remarkably, each cell has a single iron ball, and it’s in the same place in every cell.

“It’s very exciting. We find these iron balls in every bird, whether it’s a pigeon or an ostrich, but not in humans,” said Mattias Lauwers, the IMP researcher who discovered the balls.

CMCA research associate Dr Jeremy Shaw, who has studied iron in a range of animals from molluscs to humans, said it was an astonishing finding.

“Despite decades of research, these conspicuous balls of iron had never been observed previously,” Dr Shaw said. “Nature keeps surprising us with the various ways iron can be utilised by animals.”

Dr Shaw and fellow CMCA researcher Professor Martin Saunders, both of whom specialise in the use of analytical electron microscopy, helped to analyse the new iron structures and to describe them in the paper.

The finding builds on previous work by the Keays lab and the CMCA which last year showed that iron-rich cells in the beak of pigeons – previously believed to be the magnetic sensors – were really just blood cells.

“These cells are much better candidates, because they’re definitely neurons,” said IMP researcher and group leader, Dr David Keays. “But we’re a long way off understanding how magnetic sensing works – we still don’t know what these mysterious iron balls are doing.

“Who knows? Perhaps they are the elusive magnetoreceptors. Only time will tell.”

Journal reference: Current Biology

http://phys.org/news/2013-04-great-balls-iron-uncover-clue.html#jCp

Be a smartphone naturalist!

Have you ever found a strange looking bird perched on a neighbourhood tree? It looks so pretty and beautiful and you want to know what bird it is, whether there are more of them, where they came from, and when you can see it again. Somehow, descriptions like “colourful, medium-sized bird with a pointed beak” don’t really help identify the bird. And no one else is able to tell you whether they had ever seen it before.

What if we say you can simply take a picture of the bird with your mobile phone and upload it to a photo sharing network that would tell you not only its name but also who else spotted it in your locality and in other parts of the world, where else in the world the bird exists and whether there are scientists interested in studying that bird. Sounds too futuristic?

Not really, because that is exactly whatwww.projectnoah.comis set up for.

Apart from being able to upload cool photos of your favourite animals and birds and discovering others that take fabulous photos of nature, the project plugs into a network of eco-conscious people to help the world’s conversation efforts on a daily basis. Backed by the National Geographic, Project Noah allows ordinary citizens like you and me to be part of the global movement to document our biodiversity, study, conserve and enjoy nature.

Biodiversity mapping and preservation is an arduous task. When there are only a few scientists, ecologists and volunteers patiently spotting, counting and tracing species can be extremely time-consuming. Yet threats to those very species can rapidly get bigger.

Project Noah attempts to get everyone to help document and preserve biodiversity. And all it takes is a tiny effort to spot species of interests and upload it on to the web – through almost any internet enabled device.

If each person in your neighbourhood simply started tracking species of interest as and when they spotted them, pretty soon we’ll have a detailed biodiversity map – without large crews of scientists and volunteers spending great amounts of time coming to your home and your backyard to count bugs, insects, birds and trees.

What’s more, at Project Noah, you could set up your own mission and have the rest of the world help you out. For instance you could create your own mission; perhaps to document the “colourful, medium-sized bird with pointed beak”.

If you have enough users joining and working on the mission, you’ll be able to identify the kind of habitat the bird lives in and go further to protect its habitat. You’d be able to tell if the bird migrates and where it goes to depending on how its spotting pattern changes over the year. There’s no end to the number of investigations you can take on along with your fellow citizen scientists.

We all love our smartphones with their fancy megapixeled cameras. Why not put them to work and learn more about our planet!

This feature is from Agastya International Foundation (www.agastya.org), which runs hands-on science programmes for students

Try joining the International Spider Survey onwww.projectnoah.com

India use drones to protect rhinos from poachers

Wildlife authorities are using aerial drones to oversee a sprawling natural game park in Assam to protect the one-horned rhinoceros from armed poachers.

Security officers conducted flights of the unmanned aircraft over the Kaziranga National Park on Monday and will fly drones at regular intervals to prevent rampant poaching in the park in the remote area of Assam.

The drones are equipped with cameras and will be monitored by security guards, who find it difficult to guard the whole 480-square kilometer reserve.

“Regular operations of the unmanned aerial vehicles will begin once we get the nod of the Indian defense ministry,” said Rokybul Hussain, the state’s forest and environment minister.

 

 

The drones will also be useful during the annual monsoon season when large areas in the Kaziranga reserve are flooded by the mighty Brahmaputra River and three other rivers that flow through the game park, park officials said.

Hussain said the Central Bureau of Investigation (CBI) will soon begin investigations into the steep rise in rhino poaching this year.

Poachers armed with automatic rifles killed 22 rhinos last year, but have killed 16 rhinos already this year.

Rhino horn is in great demand in China and Southeast Asia where it is believed to have medicinal properties.

A rhino census conducted in Kaziranga reserve two weeks ago put their number at 2,329, up from 2,290 in 2012.

In recent weeks, wildlife authorities in Assam have deployed 300 armed guards to protect the rhinos in Kaziranga but they have been no match for organized gangs of poachers who have been managing to strike at the rhinos with increasing regularity.

“What worries us is the use of automatic weapons like Kalashnikovs by the poachers,” said Assam police chief Jayanta Narayan Choudhury.

Source: TOII

Project promises fresh beginning for Chengalpattu lake

 

 

After several years of negligence, the much-abused Kolavoy lake, one of the largest water bodies in Kancheepuram district, might soon be rejuvenated.

The lake, also known as Chengalpattu lake, will be the first water body in the Chennai region to get a new lease of life under the National Lake Conservation Plan (NLCP) of the Union ministry of forests and environment.

The primary aim under the NLCP is to infuse life into polluted lakes, which are perennial water sources, in urban and peri-urban areas.

The lake, a popular tourist destination, has been contaminated with sewage released primarily from Chengalpattu town. The livelihood of about 100 fishermen still depends on the water body, which has a capacity to store about 400 million cubic feet of water. The fisheries department generates an annual revenue of Rs. 1.80 lakh by leasing out the lake to fishermen.

Officials of the Water Resources Department (WRD) said the degraded lake does not serve as a major drinking water source. However, nearly 7.57 million litres per day is drawn from the lake and treated to be used for drinking at Mahindra Township.

According to officials, the project to conserve the lake is estimated to cost Rs. 125.19 crore.

While Rs. 30 crore would be used for desilting and strengthening the bund, a large component of the funds would be go towards providing a comprehensive sewerage network in Chengalpattu town, which generates about five million litres of sewage daily. The sewage generated from the fast-developing town is estimated to be about 600 mld by 2026.

Adequate infrastructure for sewage treatment has also been proposed in 13 surrounding villages such as Veerapuram and Oragadam.

Unless the practices of releasing sewage and dumping garbage are stopped, a long-term solution towards the conservation of the water body could not be provided, officials said.

The WRD is awaiting approval of a detailed project report submitted to the union ministry. The report proposes to promote organic farming, aquaculture and also re-introduce boating on the lake.

“We could tap the resources from rejuvenated tanks that are not used for irrigation, to supply water to industrial belts and save resources in city reservoirs,” said an official.

Officials of Metrowater recalled plans to transmit water from Kolavoy lake to Porur lake through a 50-km pipeline to tackle water crisis a decade ago. However, the proposal did not take off due to discharge of raw sewage, they said.

http://www.thehindu.com/todays-paper/tp-national/tp-tamilnadu/project-promises-fresh-beginning-for-chengalpattu-lake/article4556658.ece

Nature versus nurture — better looking birds have healthier babies

 

A female great tits’ (Parus major) appearance is shown to signal healthy attributes in offspring in a paper in BioMed Central’s open access journal Frontiers in Zoology. The black stripe across her breast and white patches on her cheeks correlate to a chick’s weight at two weeks and immune strength respectively – though the former seems to signal a genetic benefit and the latter can affect an ‘adopted’ chick’s health, suggesting nurture is involved.

Taking two mothers with different patterning, and swapping their chicks, researchers from Palacky University in the Czech Republic were able to investigate the growth and health of the infants and the ‘ornamentation’ of their mothers. They compared the offspring’s weight, size and immune strength and found a correlation between the chick’s weight at two weeks and the size of black breast stripe on the genetic mother.

The immaculateness of both genetic and foster mother’s white cheek patch was related to the strength of chick’s immune response suggesting that this was due to both nurture and genetics. In contrast the body size of a chick was related only to the body size of its genetic mother and not to ornamentation at all.

In these socially monogamous birds both the males and females are brightly coloured, however neither the cheek patch nor the stripe in males affected the health of the babies.

Talking about how the ornaments can have evolved to signal reproductive fitness, Vladimír Remeš and Beata Matysioková who performed this study explained, “Bigger healthier babies are important to the reproductive success of individuals, because they are more likely to survive to adulthood – so it is useful for birds to be able to work out which potential mates will produce the best babies. Maintaining bright colouration uses up resources which could otherwise be invested in reproduction or self-maintenance – consequently the evolution and maintenance of ornamentation in female great tits is probably due to direct selection by males.” 

http://www.eurekalert.org/pub_releases/2013-03/bc-nvn032213.php

In search of Great Horned Owl

A few months ago, Mr. Sukumar, who taught me bird watching from a few years, invited me to see a pair of Great Horned Owl near his house in Sulur.  

It was a sunny evening and the sun rays were hitting me hard. We walked in the scrub filled with grasses and thorns. Large Grey Babblers were creating ruckus, talking amongst themselves loudly and muffling the sound of other sweet birds. I saw some sparrows perched on Acacia trees and scampering around. Some warblers were perched on low grasses. They moved about quietly, and I had to watch them closely. After so many years, I still can’t identify warblers! There are so many of them and I know how challenging it is to identify them because they all look similar! Warblers can best be identified by sound than anything else.

As we kept walking, we saw some Rosy Starlings (migratory birds) siting on a wire, showing its pink feathers in the drowning rays of sunlight. It was a beautiful sight. A few Brahmini starlings were also sitting and chatting with each other.

I was in a different world, I could see no humans and that makes me absolutely happy.

When we slowly reached near the ravine where the Great Horned Owl had its home, I just stared into the space in front of me and pop, I saw one huge bird flying across me and going off to a neem tree and hiding behind it. It was the Great Horned Owl. It was a priceless moment. No words sprouted out of my mouth to tell Mr Sukumar that I saw the bird. I just stammered and said, there, pointing my fingers to the small bush. The bird was sitting on a rock, silently and beautifully camouflaged. Then it moved behind the rock, sitting behind the tree. I could only see its beautiful ears. 

 

Great Horned Owls have ears and they are about two feet in size, and prey on rodents, lizards etc. 

The bird did not move from there. I just parked myself next to the ravine, waiting for the bird to come out. The female was missing and no where in sight. With my binoculars, I could only see the cute ears of the bird. Soon, a crow passed by the neem bush and was mobbing the owl. I wondered why the crow was mobbing the owl. Maybe it did not like its appearance, or did it get fun out of the mobbing? I should maybe sometime find out why mobbing happens.

Poor owl was being mobbed and even then it refused to come out. Soon, a man came and threw a huge stone into the ravine. I was even more angered at that. Why do people want to just destroy the harmony of these beings. As it is these creatures have lesser space to survive. Here was a place, where there was water, food and shelter for the bird and we only want to destroy it.

I sat there, watching a squirrel walking into the ravine gingerly. Soon, a white throated kingfisher flew past me and straight dived into the ravine water, and then flying to a tree branch. There was so much activity happening around me, yet there was so much calmness. 

I was absorbed. After waiting for an hour, the owl did not come out. But, I was happy, it gave me a chance to look at it closely, very closely and that is a lifelasting joy for me.

As we walked back, the sun was turning orange and slipping away into the sky. We saw some paddy field pipits, bushlarks, common hoopoe and a bunch of yellow wattles lapwings. A flock of cattle egrets were flying in the backdrop of the sunset. It was a magical sight.

The winds were turning cold suddenly. At the end of the stretch, I pulled out loads of thorns from my floaters, and ended up hurting my hand. But all this fun was totally worth it. There is nothing that can give me joy of watching a bird or an insect or any creature in its natural habitat. It is something I yearn for every single moment. It makes me grounded, it makes me happy. 

 

Are sparrows native Indian species?

There have been a few conundrums on this question. I was always under the impression that sparrows have been native species and hence there are many people, not just conservationists, but also common people who are working hard to save these sparrows.

After a lot of push, the sparrows (house sparrows) got endangered tag as this would push the conservation efforts to protect the species.

In the last few months, few people, told me that sparrows are not native species and I was rather appalled by hearing this. And these few were scientists, unfortunately, who did not support me with facts as to why they were not native. I would not believe until the fact is established in a journal or literature. 

 I went ahead to check my own facts if sparrows were introduced species.

I mailed V Santharam, the most reliable and renowned ornithologist in India and this is what he told me:

 

Dear Ms Sharada,

As far as  am aware the House sparrow is a native of the Indian subcontinent. I do not remember reading anywhere that it has been introduced in India.

Here is an entry from wikipedia:

“The House Sparrow originated in the Middle East and spread, along with agriculture, to most of Eurasia and parts of North Africa.^[68] Since the mid-nineteenth century, it has reached most of the world, due chiefly to deliberate introductions, but also through natural and shipborne dispersal.^[69] Its introduced range encompasses most of North America,Central America, southern South America, southern Africa, part of West Africa,Australia, New Zealand, and islands throughout the world.^[70] It has greatly extended its range in northern Eurasia since the 1850s,^[71] and continues to do so, as was shown by the colonisations around 1990 of Iceland and Rishiri Island, Japan.^[72] The extent of its range makes it the most widely distributed wild bird on the planet.^[70]“

This is further confirmed by the fact that there are some subspecies described from India. (also Wikipedia).

I was more than thrilled receiving this email. Also, on the same day, I had discussed this issue with Mr Sukumaran, who literally taught me bird watching. He checked with his guru, the eminent naturalist Rathnam, who confirmed the existence of sparrows in Tamil Sangam Literature, addressed as il ariyum kurivi (the bird which lives in homes). 

After checking and substantiating facts, I am happy that sparrows are our own birds and we must protect them because they are critical indicators of our ecosystem. 

Next time, when someone tells you that sparrows are not native, you can refer to this blog post.

 

I have to thank Mr Santharam and Mr Sukumar for helping me solve this conundrum.