Wednesday, 10 July 2013


                                BIRD PARTNERSHIPS IN THE WETLANDS
Bird partnerships are quite common in the wetlands.

Such partnerships usually consist of one active hunter (birds which actively search for prey) and one passive hunter (birds which wait for prey to come to them). The active hunter flushes prey which the passive hunter can catch.The passive hunter acts as look out warning of approaching predators while his partner concentrates on hunting.
A very common example of such a partnership is between Little Egrets (active hunters) and Pond Herons (passive hunters).
 In the above picture 2 little egrets and a pond heron plan the morning hunt.The egrets are concentrating on the hunt while the pond heron on sentinel duty looks around and detects my approach.

The pond heron then keeps an eye on the approaching enemy (myself) while his active hunting partners concentrate on prey.
(A video will demonstrate how such a partnership works.Unfortunately the video uploading failed and I had to settle for piteous freeze frames.)

              Little egret---Pond heron Partnership (below)
 You need to be watchful if you are an egret,for in the wetlands,there are a few egret-eaters around including that dreaded biped,man. Starting a hunt is always filled with apprehension,for before you dip your head down, you need to make sure there is no one around,licking his lips for egret meat.
 May be it is better to wait till a look out arrives.
And sure enough,here comes one,a pond heron.He will stay on the shore and watch out for danger.At last,it is time to start the day's hunt!And the egrets get down to business.                           
And so the median egret and the little egret go hunting,with the pond heron as sentinel.

Another team assess their chances.The pond heron feels there is breakfast here,but his partner is not impressed.(below)                                      
  This series of pictures (below)taken from a video clip shows a partnership between a pond heron and a little egret .The little egret acts as the active partner while the pond heron acts as sentinel.Usually such partnerships are between a active hunter and a passive hunter,the latter gaining from the relationship by gulping down prey flushed by the active hunter.The former gains by the latter's sentinel duty,being able to concentrate on hunting while the pond heron keeps a look out for danger. In this case however,the little egret does not seem to trust his partner,and always maintains a position from where he can keep me in sight himself without relying on the pond heron.
    The pond heron takes up sentinel duty while the little egret hunts..                                                                                                                                    
But the egret apparently doesn't trust his sentinel,and hunts in such a position that he can keep an eye on myself as well.
This renders the hunt rather ineffective on the part of the egret..
But the pond heron faithfully fulfills his part of the bargain keeping a look out for any suspicious move from my side..

                     At last the hunt gets underway...
Large Egret--Domestic duck Partnership(below)
Domestic ducks have a rather unsafe method of feeding called up-ending.With their heads deep under water,their blunt end is rather vulnerable.

Hence what better plan than to post a look out,preferably one with a high view all round? Well,there is just such a guy around,and he sure has a good view,with the longest neck in all the wet lands!

All you have to do is to get him to stick around while you are wrong side up in the water.

The following pictures,again derived from a video clip,show a partnership between a large egret and a group of domestic ducks.The large egret stands sentinel while the ducks hunt for food by up-ending.With their heads under water,the ducks are vulnerable and they benefit from the presence of the large egret who keeps an alert watch against danger..

 It can be seen that the large egret takes his sentinel work pretty seriously,standing like a statue,head held high with unwavering attention.He in turn benefits from the duck's activities by having prey flushed from hiding by their under-water probing
The ducks can concentrate on the task in hand, knowing that the large egret will detect any danger long before it gets anywhere near.
This relationship is rather instinctive since the ducks are not in any real danger,although a few marsh harriers and lesser spotted eagles do visit the wetlands often.
             Little Egret---Little Cormorant Partnership(below)
This is a very common partnership in the wetlands.Both being active hunters,this partnership displays hectic activity.Note that in shallow water,the cormorant leads the partnership,while in deep water,the egret leads,with the cormorant in tow.In such a partnership,the egret benefits by having prey driven to him by the cormorant's  underwater hunting.And the cormorant benefits by having the egret as a look out while his own head is submerged.

                     In  Shallow water,the cormorant leads the attack, while the egret waits behind for fleeing fish.  (below)                                         

With the egret nearby ,the cormorant can afford to dip his head below water
He looks up just to make sure his friend is doing his job..
           Reassured,he goes back to work and the hunt resumes..

                 In to Deeper water,.. and the egret leads the charge.(below)                   ( Poor picture quality is regretted.)          
The little egret walks in front and the prey which run from him are picked up by the cormorant swimming half submerged behind him.The presence of the egret enables the cormorant to concentrate on such a hunting method since the former with his head well above water level ,can easily spot danger.As the cormorant probes under water,fish swim forward and the egret gets his share of the partnership.

But his method of catching his food is not very elegant.
                     The hunt resumes , silent and diciplined.
                             Spotting a snack,the egret moves ahead.
                      And it is chaos again..
Things go from bad to worse as the prey gives the egret a run for his money.
                                                                                                                                          Things quieten down again and the hunt resumes.
Reaching the end of the pond,the egret turns an arc,the cormorant following closely.
                             The hunt proceeds in the opposite direction,,

                    Every few minutes the peace is shattered as the  egret  spots a fresh snack.
                               And pandemonium reigns supreme ....
                 And then the hunt resumes in peace and order.

                           (Poor picture quality is regretted.)

               Partnership Between Small Blue King fisher And Domestic Ducks. (below)
  In this partnership,again the ducks do the active hunting while the king fisher acts as look out from his high perch,and he in turn benefits by having fish flushed from hiding by the duck's activities. He takes his sentinel duty rather seriously and sits it out with great concentration.Anyway,the ducks activities will flush out his' prey and save him hours of boring wait for a fish to stray close enough. .                    


   Partnership Between Little Grebe And Domestic Ducks.(below) 
In this partnership,it is hard to see what benefit the ducks derive from the presence of so small a diver as a dab chick. The dab chick however gains by having the ducks as look outs above water while he dives for food under-water.The ducks rather see him as a competitor and were seen trying to shoo him off with neat pecks,but in vain.                     
       A dab chick invites himself to join a flock of domestic ducks

  The ducks have nothing to gain by his unwarranted intrusion.

                 But he can use them as look outs while he is diving.

                   So he hangs around among his unwilling companions.

                            Partnership Between Large Egret And Little Cormorant.(below) 
 Here again,the large egret stands like a wax model,keeping a sharp look out for danger while the cormorant hunts actively under his watchful eyes. Any frog or such other prey flushed by the cormorant will ensure the large egret his share of the deal.
 In the above clip,the cormorant is under water while the large egret acts as look out.
                   In the above clip,the cormorant make sure his friend is not cheating..
                Sure,he is not.The large egret spots a raptor in the sky,...
    The cormorant,briefly halts his hunt,but the large egret is sure the raptor is too high up to cause trouble.

             Partnership Between Little Egret and Domestic Ducks
A flock of domestic ducks invading a wetland is a sickening sight to us,but to most wetland birds,it is a most welcome sight,their incessant quacking, music to their ears.The ducks drive fish,crabs etc before them and the wetland birds can enjoy the bounty.
Little egrets are quick to take advantage of a duck-invasion.In the pictures below,a little egret makes the most of the confusion that follows in the wake of a duck-raid and helps himself to some easy snacks.                                             

The little egret trails the ducks,picking up prey fleeing from these gluttons.
 He is an active hunter,but this way he can save precious calories.
                   by making the ducks do all the hard work..
 All he has to do is keep his eyes and mouth open..
               Why waste yourself when someone else will do it for you.
These are only some of the fascinating inter-species relationships one sees in the wetlands.The ingenious ways in which different species adjust to each other's life style,and indulge in co-operative hunting makes me wonder whether they are not endowed with far more intelligence than we generally think!
                                                                         THE END

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