Friday, February 22, 2013

Animal Communications -- Like Dolphins, Like Geese, Like Humans

A pair of Canada geese with heads and necks tucked low to brace against punishing winds yesterday at Central Park Reservoir.
"Dolphins May Call Each Other by Name"

(This fascinating story was also covered last night on ABC World News with Diane Sawyer.)

Thanks to field research by scientists, we now know that elephants, apes and dolphins communicate with each other in far more complex language than was ever thought.

We should not be surprised that they have special language identifications for each other, as humans do names.

But, this is not just true of these specific animals.

When landing after a long migration, Canada geese "call out" to each other in something that sounds like a roll call in a school classroom.  The honks are different in tone and length and occur among groups of geese. 

There is little doubt that Canada geese have distinctive names (or language identifications) for each other.  Its how they stay organized and together when flying, wintering or grazing with many other geese.

We are only scratching the bare surface of animal communications.

The "Arctic Cold Blast" that forecasters warned about last week came to pass in New York City.

Although less than a month away from spring, one would never know it by the sub freezing temperatures and whipping, punishing winds of the past week.

Fortunately, the bitter cold spell was punctuated by one extremely warm day last Saturday when temps ballooned up to the mid 50's.

This was enough to melt much of the frozen ice water, both at Harlem Meer and the Central Park Reservoir.

Nevertheless, the next day temps dropped more than 30 degrees and wind chills plunged to zero.

I was nervous that such sub freezing temperatures might ice over again, the entire lake at the Meer.

But, such fear turned out to be unfounded as it seems the blustery, (at times, 45MPH) winds kept the water constantly moving and thus, incapable of icing over.

But, it has not been an easy week for the ducks and geese of Central Park despite the stll mostly open, moving water.

I have read that geese and mallards can survive temperatures as low as zero and even lower.

That is probably true, but they have to make many adjustments in order to deal with that kind of relentless frigidity and wind:

One of those adjustments is keeping their heads and necks low and tightly tucked at times, into their bodies.  Apparently this helps geese and ducks to brace the harshest of winds and conserve body heat, much as humans holding their arms close to the body when cold.  

Another adjustment is squatting down on breasts and bellies when on frigid ground (also, presumably a way to conserve body heat). 

However, during the coldest of weather, the geese and ducks mostly stay in the water as apparently even partially iced over lakes are warmer than frozen ground.  

I am not sure about ducks (who seems to have a faster metabolism than geese), but it appears that Canada geese are able to sometimes go days or weeks on very little food.  Perhaps this explains why they eat and graze so much during the summer and fall. 

Its apparently necessary to build up fat reserves to help get geese through the winter.

During this winter, I have frequently observed the migratory geese staying at the Reservoir in Central Park.   Most times, the geese are "hunkered down" with heads tucked into their backs on the ridge that goes across the Reservoir or on ice. 

They did not seem to move around very much, particularly during the depth of the winter.

In the past couple of weeks however, there has been a great deal of movement -- and communication -- by the geese.

Some geese left on what apparently is early migration.  Other geese arrived. And still others are "pond hopping" around the park and even grazing on some of the lawns, (including, Harlem Meer) most likely in preparation for a long and physically taxing migration.

It is in fact, quite interesting to observe geese just prior to them taking off for an evening graze or migration. 

Last night, just following sunset, many gaggles of geese slowly gathered themselves along the north east portion of the Reservoir.  There was a great deal of honking and "talking" as the geese carefully organized themselves into their established groups or families. 

It was too bitter and windy for me to hang around long enough to actually see them take off. (This gathering is actually a time consuming process.) Nor, could I know if all the discussion and organization was in preparation for long migratory flight to Canada or the sub arctic or just a hop flight over to the North Meadow or even Harlem Meer.

One thing is for sure, however.

The honks of geese are not just idle, random noises in the wind.

They are real language, identification and communication that enables the geese -- like dolphins -- to organize and stay together whether on land, water or in the air.

We have barely begun to scratch the surface of animal communications.  -- PCA


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