Wednesday, January 28, 2015

ZOO: Is it a Bird? Is it a Plane? No, it’s a Flying Squid!?

24 January 2014

There have always stories about flying squid, but no actual photographs until Jun Yamamoto of Hokkaido University and his team took pictures of squid in flight in 2011.  Yamamoto said, “[W]e should no longer consider squid as things that live only in the water.”  The team’s study and photos appeared in Marine Biology.


Yamamoto and his team were in the Pacific Ocean east of Toyko tracking a shoal of squid.  Suddenly, about 20 of the 8 inch long creatures shot out of the water and into the air.  Squid launch themselves by shooting a jet of water.  Once in the air, these ten-legged creatures not only form make-shift wings by opening their fins and spreading out their legs, but even flap their fins to stay in the air little bit longer.  Gliding through the air for up to 100 feet, they fold in their fins just before re-entering the water.  Their whole flight takes about 3 seconds.


Biologists, themselves, had seen and reported flying squid.  That some squid “fly” was an accepted scientific fact.  After their own sighting, Biologists Silvia Maciá and Michael Robinson of the University of Miami gathered similar reports from other scientists and co-authored a study published in 2004 in the Journal of Molluscan Studies.

Even before Yamamoto’s photos, there was something more than eye-witness reports.  There was, what you might call, circumstantial evidence.  What was the “smoking gun?”   A lot of “morning-after encounters” in which squid were found on the decks of ships — in the morning.  Researches assumed that the night-feeding squid had wandered into shallow waters.  When they were frightened, they “took flight” with some unlucky flyers landing, not in the sea, but on the deck of a ship.

Before the Hokkaido University team caught their photos of squid in flight, there was little photographic evidence.  Retired geologist and amateur photographer Bob Hulse had taken a few photos off the coast of Brazil.  But, for researchers, the details in these photos didn’t reveal a lot about how squid fly.

The photographs taken by Yamamoto and his team are a real achievement. Catching squid in flight is extremely rare and all agree that flights “happen so quickly.” “You really have to be in the right place in the right time.”



Thursday, January 22, 2015

ZOO: The “Air Shark” – The Tigerfish Flies & The Fish’s “Choice”

24 January 2014

[Humor]

Africa’s Tigerfish was caught jumping out of the water . . . into the air . . . catching a bird . . .  in flight . . . and taking it home for dinner.

[video] tigerfish dining alfresco

It’s bad enough that sea creatures can attack us when we go into the water.  About 40 years ago, the film, Jaws, scared movie-goers to the point that people stopped going to beaches for fear of being attacked by sharks — but only if the swimmers went in the water! The next film, Jaws II, had promotional trailers warning:  “Just when you thought it was safe to go back in the water.” But at least you were safe on dry land.

Poster: Jaws Film: Jaws
Poster: Jaws II

In 1975, the first in a series of SNL sketches took away that last safe place – dry land.  The Saturday Night Live writers introduced the world to the “Land Shark” — a predator that could strike on land or sea.   In each sketch, a city-dweller would hear a knock at the door and a voice would call out, “telegram,” “plumber,” etc.  When the door was opened, in plunged the “Land Shark” (or a giant foam rubber version of the “Land Shark”).

Saturday Night Live/SNL
Land Shark” [image][video]

Like a few other fictional villains, the “Land Shark” developed a real life copycat, the “Land Catfish.” Introduced to France’s River Tarn, about 20 years ago, a common species of catfish was starving as its food of choice, crayfish, decreased in numbers.  Most species would have the good graces to continue to starve and die out.  Not these catfish.  Instead, they made a different choice and “learned” to do something no member of their species has ever done before – catch and eat land animals.

Hovering in the water, near flocks of pigeons, these catfish wait for one of the birds to get “too close” to the water.  Then, these (sometimes, four-foot long) cats jump out of the water, grab a pigeon and take it home for dinner.

Fisherman, who saw the Land Catfish at work, found it – really creepy.  And, so do I.  Underwater creatures intentionally jumping out of the water to grab some land animal, drag it back into the water, and eat it?  I’ve seen stuff like this in old horror movies!

“Catfish grabs pigeon” [video]
Catfish hunt pigeons in France
Oh, Dear God No: Here Are Some Catfish Hunting And Eating Pigeons

Study of these Land Catfish revealed another upsetting fact.  Those catfish that learned to hunt “land prey” developed a taste for land animals.  These fish stopped eating their usual crayfish and started eating almost nothing but land animals.   Being a land animal, myself, I don’t find any of this comforting . . . at all!
Also, in the last year, we found out about another sea creature that just won’t stay in the sea.  A few months ago, an octopus was caught crawling out of the ocean and leisurely shopping for snacks on a California beach.  But, unlike the catfish, the octopus didn’t suddenly “choose” to start hunting on land in the last week or so.

Octopus Walks on Land at Fitzgerald Marine Reserve
Octopus crawls out of water and walks on dry land

Octopus experts say that octopuses have always done this.  These creatures jump out of the water onto land all the time.  (I don’t know that I wanted to know that.)  The only thing that was unusual was that the octopus starring in the video was shopping on the beach during the day.  Usually, octopuses crawl out of the sea and go trolling for a meal on land — in the dark of night.  Well, that’s the end of my evening strolls on the beach!  But, it gets worse.  Octopuses even jump onto crab-fishing boats, climb into barrels of crabs (their favorite food), and pig-out.

Land-Walking Octopus Explained

Just when you thought it was safe to go near the water.
But just as this “year of discovery” of the real Land Sharks was ending, another safe place was invaded by predator fish.

Welcome the “Air Shark.”

A Tigerfish was caught on video jumping out of the water . . . into the air . . . and catching birds in flight.  The Tiger is just the sort of fish you don’t want jumping out of the water and catching passing . . . animals.  Who knows what else it might catch when it’s up there — water-skiers, parasailers, . . .  small aircraft?

Fish Can Catch and Eat Flying Birds [African Tigerfish]

Called the “African piranha” the Tigerfish has no winning smile, but it sure has a toothy grin.  [image]  Hoping for some comfort, I looked up the tigerfish on Wikipedia.  After saying that game fisherman call these fish “the African piranhas,” the entry goes on, reassuringly, to say that the two fish aren’t so much alike because the tigerfish and piranha are two different species.  (I sigh with relief.)

But, then, the entry goes on to say that tigerfish and piranhas do have just a few things in common.   Both have “interlocking, razor-sharp teeth”, “are … extremely aggressive … predators”, and “often hunt in groups.”  Oh, don’t let me forget to mention that each member of  the tigerfish “pack” weighs about 110 pounds.  And another thing, tigerfish have been known to attack humans.

Really makes you want to book that ski vacation at Africa’s Lake Malawi, doesn’t it?

Tigerfish

Unlike the Land Catfish, the “Air Shark”/Tigerfish didn’t just choose to start hunting flying birds — yesterday.  There have been stories of this fish jumping out the water and grabbing birds in flight since the 1940’s.  But, like the octopus’s strolls on the beach, the flight of the tigerfish was never caught on video until this year.

Nico Smit, director of the Unit for Environmental Sciences and Management at North-West University in Potchefstroom, South Africa, was part of the team that caught the “Air Shark” catching a quick bite.  He said that the whole “event,” (meal for the fish, “big sleep” for the bird) happens so fast that it took a while before the researchers were sure what they were seeing.

It didn’t just happen fast.  It happened often.  They saw 20 “catches” the first day and about 300 during the next two weeks.  The “event” was caught on video for the first time by team member Francois Jacobs.  The team’s findings were published in the Journal of Fish Biology and Nature.com.

Tigerfish catches bird video shocks scientists worldwide
National Geographic

With this report, yet another element of our environment, the air, is threatened by killer fish.  I can hear someone say, “Yeah, but unless you’re a bird flying over a lake in Africa you’re safe.”  Well, 20 years ago, French pigeons thought they were safe from catfish attacks on the shore of the River Tarn.  Then, one fine day, a catfish just “chose” to become a Land Catfish and start jumping out of the water, onto land, to grab and eat the nearest animal.  You wouldn’t have wanted to be the next unlucky pigeon that went to get a drink of water from the river!

This “choosing” thing worries me.  Now, animals just “choose” to eat completely different things than they’ve been eating for the last few thousand years.  Just a couple of weeks after I heard about the Land Catfish, I visited an evening holiday light display at the Missouri Botanical Garden.  In the freezing cold, I walked along the dark paths admiring the beautiful lights.  I thought back to the Garden, in the summer, with giant koi fish in the large pond surrounded by the Japanese Garden.  You can feed these large fish as they gather around the bridges and shoreline to gobble up food pellets.

Gee, I thought, those fish must have rough time under the frozen ice.  They go for months with little food.  I bet they get really hungry.  Looking out into the pitch blackness a few yards off the path, I wondered how close I was to the water.   No, I reassured myself.  I’m safe.  After all . . . koi fish couldn’t be dangerous.  These fish look like giant goldfish.  The only difference is some have those whisker-looking things.  You know, . . . like . . .  catfish!?  Those clever, predatory, and hungry river-beasts that are scarfing down pigeons in France!

I stuck to the paths farthest from the water.

Missouri Botanical Garden
Koi Fish [image]

I didn’t like this new trend toward “choice” with fish deciding to leave the water and eat anything that happened by.  But I didn’t think it was a too big a problem until I stumbled across a story about another sea animal.  One that jumps out of the water regularly and sails through the air.  Everyone says this creature just jumps out of the water and dives back into the water without “eating an in-flight meal.” But, now, I know that sea creatures can just “choose” to change their feeding habits any time.

Jun Yamamoto of Hokkaido University and his team were tracking squid in the ocean east of Tokyo when 20 of these ten-legged creatures flew out of the water for a distance of about 30 meters.  They like to fly.  They spread out their fins and legs like wings to stay in the air.  They’ve even been seen flapping their fins to stay in the air a little longer!

Same story, different day – there were rumors about flying squid for years, but this was the first time they’ve been caught on film.  Yamamoto said, “[W]e should no longer consider squid as things that live only in the water.” [!]

Welcome the Air Squid.

Flying Squid [image] [video]
Squids ‘can fly 100 feet through the air’

Everyone’s worried about the safety of the flying squid.  Birds might eat them while they’re flying through the air.  Sure, but what happens to the birds when the flying squid decide they’re hungry?   “Oh, but these flying squid don’t eat birds or . . . (glup) . . . water-skiers.”  Of course, not.  Not yet.  Not until, like the French Land Catfish, they “choose” to start eating birds, people, . . . small aerial drones.  Who knows?

Some will say, “But only small squid fly.”  “It’s not like the flying squid were those giant 12 foot long, 330 pound squid that live deep in the ocean.”  Correction: Just because they’ve never been caught on video, doesn’t mean giant squid don’t fly.  And, even if they’ve never flown before, what make you so sure they won’t choose to fly in the future.  Suppose they do.   And suppose they choose to flap their fins so fast that they start flying like birds.  That’s all we need — giant flying squid trolling the air above the water like a bunch a pterodactyls.

First, there was Jaws with its great white shark.

Don’t go in the water!

Then, the Land Shark “inspired” imitators — the Land Catfish and Land Octopus.

Don’t go near the water!

Finally, the Tigerfish becomes the “Air Shark.”

Don’t fly above the water!

The End?

Mark Grossmann of Hazelwood, Missouri & Belleville, Illinois
About the Author














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Thursday, January 15, 2015

ZOO: Meet the “Air Shark” – Tigerfish Catch Birds in Flight



24 January 2014

African Tigerfish jump out of the water . . . into the air . . . and catch birds in flight.  Tigerfish, in a storage lake for the Schroda Dam in South Africa, were caught, on video, grabbing barn swallows out of the air.

[video]

Sometimes called the “African piranha,” the tigerfish is a scary looking fish.  [image]  However, the tigerfish and piranha are two different species with the tigerfish winning contest as the bigger and meaner of the two.

Like piranhas, tigerfish have “interlocking, razor-sharp teeth”, “are … extremely aggressive … predators”, and “often hunt in groups.”  Both species have been known to attack humans.  But unlike the relatively small piranha, an individual tigerfish weighs about 110 pounds.

Tigerfish

The story of the tigerfish jumping out the water and grabbing birds, in flight, has been around since the 1940’s.  But, for the first time, an “air-feeding” tigerfish has been caught on video.

Nico Smit, director of the Unit for Environmental Sciences and Management at North-West University in Potchefstroom, South Africa, was part of the team that caught the tigerfish feeding on birds.  He said that the whole “event” happens so fast that it took a while before the researchers were sure what they were seeing.

It didn’t just happen fast.  It happened often.  They saw 20 “catches” the first day and about 300 during the next two weeks.  The “event” was caught on video for the first time by team member Francois Jacobs.  The team’s findings were published in the Journal of Fish Biology and Nature.com.

Tigerfish catches bird video shocks scientists worldwide

The tigerfish favors the twilight as the time of day for hunting birds in flight.  This fish has two varied approaches to the hunt.  Sometimes, the tiger will swim near the surface of the water following the birds, in flight, before jumping up into the air to make a catch.  Other times, the fish will lurk in the deeper water tracking the birds.  Then, it will leap out of the water and ambush a bird as it flies by.

Smit is amazed at the skill displayed by the fish in spotting and pacing the birds from the water.  Not only does the fish have to estimate and exceed the birds’ speed, but the tiger has to compensate for the light refraction in water.  This is quite a trick. The angle of the light changes when it passes from the air into the water.  This makes estimating the location and speed of objects in the air a lot tougher.

This has been quite a year for videos catching aquatic animals feeding out of the water.  First, Julien Cucherousset of Paul Sabatier University caught catfish on video in France’s River Tarn as they practiced their recently acquired skill of jumping out of the water to grab and eat pigeons wandering on shore.  Then, an octopus was caught on video leaving the ocean for a stroll on a California beach in search of meal.  And, now, a fish leaps into the air to catch birds — in flight!

Catfish hunt pigeons in France

Octopus Walks on Land at Fitzgerald Marine Reserve

Where will it end?

Maybe it hasn’t.

In another recent “photo first,” Jun Yamamoto of Hokkaido University and his team recorded squid leaping out of the ocean just off the coast of Japan.  These “flying” squid travel almost 100 feet before reentering their water.  Not only do these flyers extend their legs and gills, like wings, to stay airborne, but they actually flap their fins for some added “bird-like” lift.

Flying Squid [image] [video]

Squids ‘can fly 100 feet through the air’

You have to wonder (or worry) what’s going to be walking or flying out of the water next.

Mark Grossmann of Hazelwood, Missouri & Belleville, Illinois











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Thursday, January 8, 2015

ZOO: The “Land Shark,” The “Land Catfish” & The “Land Octopus”



31 October 2013

Decades ago, the film, Jaws, was credited with terrifying movie goers to the point that they avoided beaches for fear of being attacked by a real version of the film’s animatronic great white shark. [image] [1] Then, there was a sequel with promotional trailers warning:  “Just when you thought it was safe to go back in the water.” [image]

But at least you were safe on dry land.  Right?

Saturday Night Live’s writers decided to take away that last refuge of safety by presenting a predator that could strike on land or sea.  In 1975, the first in a series of SNL sketches featured a hapless urban dweller who hears a knock on their front door. 

When the caller is asked to identify themselves, a voice on the other side of door says “repair man” or “door-to-door salesman.”  Then, when the door is opened, in plunges the “Land Shark” (or a giant foam rubber version of the “Land Shark”), which completely consumes the victim. [2] [image] [video]

Well, the Land Shark was just a joke.  Wasn’t it?

It was.  But, like more than a few fictional, on-screen characters, the Land Shark seems to have an imitator.

Just when you thought it was safe to go near the water?

Catfish in France have learned to hunt pigeons. [3] [4] Fishermen on the France’s River Tarn were more than shocked to witness catfish “loitering in shallow water near sandbars populated by pigeons.”  When one of the birds wandered too near the water line, it was a “Land Shark” experience for the bird and a meal for the catfish. [video]

When Julien Cucherousset of Paul Sabatier University heard the story from the bewildered fisherman, he captured footage of the “event.”   The on-line video went viral. The first time I saw the video, my reaction was almost that of an academic naturalist.  “How fascinating,” I thought.

At least, I thought it was fascinating until I learned that these catfish were three to four feet long.  So, I am only about 2 feet longer that the largest of these “Land Catfish.”  My next thought?  Would I . . . ?  Yes, I assured myself.   I’d win — if caught in a shoreline struggle with an overly aggressive four-foot catfish.  Then, I reflected.  Suppose I was sick and weak that day?  I didn’t try to answer that question.  I just . . .  thought of something else.  [5]

At first, I was comforted by the fact that this particular species of catfish wasn’t native to France, but had been introduced to the Tarn River about 30 years ago.  I imagined some weird, predacious species of catfish from the depths of the Amazonian jungle had been imported and accidentally released into the river.  But, when the full story unfolded, it turned out that these were just plain old catfish.  And they had been intentionally released into the river. [6]

Over the last three decades, the waters of the Tarn became less populated with crayfish and other smaller fish.  So, the catfish began feeding on land prey — a behavior no member of its species is known to have engaged in before.  These fish hover under the water near the shore watching their prospective, terrestrial prey.  Then, when an opportune moment presents itself, they leap out of the water onto the dry land, grab their prey, and leap back into the water taking there land-dwelling victim with them.  Then, the “Land Catfish” enjoys a leisurely meal in its underwater home. [7]

Autopsies of the catfish in the area revealed that not all of the fish were eating pigeons.  However, those that were tended to abandon their old diet of crayfish and other small fish focusing more exclusively on land prey.  [8]

Somehow, I found the casual way in which these animals extended their hunting range disconcerting.   But more disturbing was the autopsy’s suggestion that some fish had developed a taste for land animals — ignoring their old fare of crayfish and other small fish to focus almost entirely on pigeons.  As a land-based mammal who enjoys strolling along the shores of natural bodies of water, I’m still not entirely comfortable with these developments.

One writer, attempting to minimize the strangeness of it all, noted that African crocodiles jump out of the water and grab zebras.   And whales beach themselves on the ice to nab penguins for dinner.  But these are hardly apt comparisons.  Crocks and alligators are air-breathing lizards.  They just hang-out in the water.  Whales are also air-breathing mammals who have adopted a fish-like lifestyle. [9]

Neither of these examples could compare to a plain old fish intentionally jumping out of the water to grab some terrestrial creature, drag it into the water, and eat it.  I’ve watched scenes like this in old horror movies.  I’ve always loved to stroll along the shore of almost any waterway, but is it safe?  Where I live, my favorite body of water is the Mississippi River.  After seeing this video, I checked.  The Mississippi is teaming with catfish – those same enterprising, opportunistic, and hungry sea-beasts that are scarfing down pigeons in France!

On calmer reflection, I realized that the Land Catfish is actually engaged in the mirror image of human sea diving.  Somehow, I’d always thought that land creatures dived into the water to feed on unsuspecting sea creatures.  Not the other way around.  And human beings had the distinction of being the only creature that could learn to dive into the water for food (and maybe a few pearls).  Now, the Land Catfish has turned the tables on us.

But the Land Catfish isn’t the only sea creature that feels free to promenade out onto the dry land to pick up a meal.

A few decades ago, I remember strolling along a Sarasota beach at midnight — my feet kicking through the white sand.  In those distant days, you could still find yourself quite alone on the beach at night.  Absolutely taken with the beauty of the Gulf, I remember thinking how nice it would be to just stretch out on the sand and sleep in the cool breeze off the water until sunrise.

All those years ago, I would still have been quite safe from human interference, but I would never have thought of the possibility of something coming up out of the sea.  I can imagine the psychological trauma I would have experienced if, in the middle of that peaceful night’s sleep, I had stirred awake and opened my eyes to see an eye looking back at me:  the “dominant eye” of a local octopus.  

The creature wouldn’t have been interested in me. It would have just been “passing by.”  But, after an experience like that, I would have moved to the top of a mountain — as far away from the water’s edge as I could get.

Not long after I saw the “Land Catfish” video, a story broke about a “Land Octopus.”  The terrestrial excursions of the octopuses have stayed pretty much out of the public eye until recently when one of these strange creatures was caught in the act – on video. [video]  An octopus was seen grabbing lunch, not while roaming where it belongs – underwater — but, instead, crawling around on the beach casually grabbing a few snacks.  The witnesses got a video camera and the rest is internet history.  [10]

How long has this sort of thing been going on, I wondered?  Well, octopuses have been doing this since . . . forever.

The Land Octopus starring in the San Mateo County, California video was not engaged in any particularly unusual behavior.  Marine biologist James Wood explained that several species of octopuses make brief forays onto land for a meal. [11]  Most discomforting was his explanation of why the public is so ignorant of this particular octopus behavior.  Octopuses leave the water all the time.  They just do it when they won’t be seen.  Wood explained that most octopuses are nocturnal, sneaking out of the water at night to enjoy their meals unobserved. [12]  Well, with this factoid, my nocturnal seashore walks are over.

The octopus caught on video was probably engaged in the octopus version of grocery shopping.  Julian Finn, a senior curator of marine invertebrates at the Museum Victoria in Australia explained that octopuses frequently emerge and hunt in tidal pools when the tidal waters recede.  The octopus examines these “grocery shelves” either with its eyes, (octopuses have rather good vision), or feel for food with its outstretched arms (tentacles?). [13]

However, not so typically, the cephalopod shopper in this video is seen discarding an empty crab shell during its shopping spree — after eating the occupant.  Either this octopus was particularly hungry and couldn’t wait to get home, with the crab serving as a kind of fast food snack or, even with eight arms, carrying all those groceries got to be too taxing.  If the “groceries” get too heavy, octopuses often stop and eat their way to a lighter load. [14]

However, shopping isn’t the only thing that brings octopuses out of the water and onto dry land.  Finn explained that octopuses also “lurch” out of the water onto land to escape danger.  Wood recalled an incident in which he was chasing and photographing a common octopus “when it crawled out of the water, across eight feet of rocks and went back into the water” apparently hoping this maneuver would confuse the pursuing photographer. [15]

Mercifully, octopuses aren’t interested in eating people.  Hostile interactions between octopuses and people happen when the octopus perceives a person as a threat rather than as a potential meal.

Still, even if I’m not on the menu, I wouldn’t like to encounter an octopus as I was strolling or resting on dry land.  Imagine if I’d paused to catch my breath on that eight foot expanse of rocks when the Land Octopus jumped out of the water in its attempt to shake the pursuing James Wood.  After literally running into an octopus on dry land, you can bet that it would be a long time before I thought it was safe to go anywhere near the water.

Mark Grossmann of Hazelwood, Missouri & Belleville, Illinois

Of interest:


Thursday, January 1, 2015

ZOO: The Rhea – the Ostrich’s and Emu’s American Cousin


20 February 2014

Africa has its ostrich, and Australia has its emu. However, many are unaware that the Americas have their version of these famous birds: the less-famous rhea.  This large, grey-brown bird is, on first sight, unmistakably the close relative of both the ostrich and emu.


However, the rhea grows to a height of just a bit under 6 feet, shorter than its, sometimes, 9 foot-tall cousin, the ostrich.  The rhea is, also, a comparative feather-weight at just 88 pounds when compared to its, sometimes, 240 pound African cousin.  But the rhea is fast enough to give the ostrich a good “run for its money.”  With a top speed of 40 mph, the rhea might not win a race against the fastest ostriches.  But that’s no disgrace because the ostrich, with its highest speeds clocked at about 43 mph, is the fastest land animal on earth.


Perhaps, speed compensates for flight.  Like the other members of its intercontinental family, the rhea is a completely flightless bird.  It’s preference for the ground earned it the name “rhea” given by German zoologist Paul Möhring, in 1752.  Named after a Greek Titan, Rhea, the name literally means “ground.”

Certainly, Möhring’s name is less creepy that the rhea’s native name, ñandú guazu, meaning spider!  The rhea earned this arachnid nickname through its habit of half extending its wings when it runs.  Although it’s actually using its wings for a bit of aerodynamic assistance, the half extended wings move up and down, as it runs, giving distant observers the impression of a giant spider.

Similar to the ostrich in appearance the rhea not only differs in its smaller size but, also, in its distinctly grey-brown plumage.  Unlike most birds, the rhea has 3 rather than 4 toes.  However, it doesn’t stand out as an oddity among its cousins.  The ostrich is the only bird on earth with only 2 toes.

And there’s another twist.  There are two varieties of rhea, the “Greater” and the “Lesser.”  Both live in about the same locations in South America.  A would-be birdwatcher might be frustrated because the two types aren’t so very different.   In other words, it’s hard for an observer, even at close range, to be able to tell the “greater” from the “lesser.”

Rheas are only found in South America — typically in the countries of Argentina, Bolivia, Brazil, Chile, Paraguay, Peru, and Uruguay.  These birds tend to live in flocks of 20 to 25 and make an odd sight when the flock is frightened and running from danger. The individual birds and the flock run with a zigzagging course.  They use their wings as sort of “air rudders” extending one, then, the other to produce the zigzag motion.  As a matter of fact, for a flightless bird, the rhea uses its wings quite a bit.  But, as a running bird, it uses its wings more like a boat’s sails than an aircraft’s wings.


During mating season, the flocks dissolve as males and females pair off and mate. Though normally silent, during mating season, the male rhea makes an extremely loud booming noise.  An individual male will mate with several females.  After mating, the rhea’s home life mirrors that of the Australian emu.   Each female lays her eggs in a single nest — one every other day for a week to ten days, .  Then, the female abandons them to the male, who maintains the nest, sits on the eggs and otherwise cares for the eggs and hatchlings.



These birds have few predators other than human hunters.  In South America, rheas provide feathers for feather dusters, skins for leather goods and, even, eggs and edible meat.  Unlike Australia’s emu, the rhea is not raised as a ranch animal.

[video] Wild Kingdom

Mark Grossmann of Hazelwood, Missouri & Belleville, Illinois