Sunday, May 31, 2015

The Curious and Complex Relationship Between Mallards and Geese


Only days old, readiness and preparedness to defend the family is already ingrained and being tested in these newly hatched goslings.
And they are being tested by the pesky mallards who, though harmless, represent unique teaching opportunities for geese and goslings.
 
One of the things that has always fascinating me in the years of observing waterbirds is the curious relationship between mallards and geese.
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The two species generally respect each other and hang out together. During stress times (such as winter) ducks and geese often cooperate mutually for the benefit of both. This is especially true in situations of thin ice covering water (Geese can break up thin sheets of ice, while mallards, being smaller and quicker, help to maintain the open water once the ice is broken through) or snow on the ground (Geese can peck and pack down snow, allowing mallards easier opportunity to feed).
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That said, it doesn't mean the two species necessarily "love" each other.  On the contrary, there is some competition between them for food sources and mallards seem particularly adept at annoying the hell out of geese (sometimes I think, for the sheer fun of it). 
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The latter is particularly true during the nesting and gosling-raising season.
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For some strange reason, mallards particularly seem to enjoy hanging around geese when the larger birds are nesting or rearing young. While not certain, I am guessing part of that has to do with security reasons. Geese are particularly vigilant during these times and that affords the mallards an extra sense of protection and early warnings of danger.
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I recall particularly, a mama mallard with 9 ducklings who used to bring her ducklings every night to roost a few feet away from the goose family at Turtle Pond in 2010. Mama mallard apparently felt very safe and protected with her brood that the gander of the goose family was literally "on guard" throughout the night. As matters turned out, it was a smart strategy as all nine of her ducklings survived -- something highly unusual for mallards.
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Since the two pairs of geese nested at the Central Park Reservoir over the past month, it has been interesting to note (in both cases), the mallards hanging out near the nesting sites on a regular basis.
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Both ganders were clearly annoyed with the mallards and frequently gave chase -- usually to no avail as the mallards always returned.
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Sadly, all the eggs of one of the goose pairs (John and Mary) mysteriously vanished one day and thus the relationship between the nesting geese and the mallards hanging with them, was quickly aborted.
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But Hansel and Greta succeeded in camouflaging their eggs from easy view by humans and thus the nesting process moved forward.
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After a while, Hansel appeared to "give up" the constant chasing of mallards (probably to save energy for more important things) and tacitly accepted their presence as they represented no viable threat to the eggs.  The mallards were just annoying.
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That all changed however, when the eggs finally hatched this past week.
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Since then, both parents have been quick to let the mallards know they are no longer welcomed or accepted into the sacred vicinity of the goslings.  
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But, as always, the mallards are very slow to "get the message" and always return with the seeming confidence that the geese are not actually going to harm them.
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But, shock of shocks, it is no longer just the parents pecking at or giving chase to pesky mallards, but also the goslings -- goslings who are not even a week old!
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I truly could not believe my eyes last night when seeing one of the 4-day-old goslings running after and actually pecking a mallard drake on the butt along the rocks at the Reservoir. -- Mind you, we are talking of a tiny yellow ball of fluff chasing out a mallard drake at least four times the baby's size!
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At first I thought I was imagining things or the scene was some kind of fluke, but it actually occurred at least 3 or 4 times for, as always, the mallard returned.  (Even two other people watching the scene were completely flabbergasted. "Who would ever think...?" said the man to his equally astonished wife.)
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Due to goose harassment and egg destruction policies in Central Park, we sadly don't get much opportunity to observe geese raising goslings. Of the few opportunities that have occurred, I have been highly impressed with how quickly goslings learn from parents and adapt to fast changing circumstances and/or dangers.
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But, that they would have the instinct (or learn this fast) to protect the family at only 4 days of age is beyond anything I have read or seen even on a Nat Geo documentary.
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As for what the mallard might have thought when being chased and pecked by a gosling only days old?  I have no idea, but imagine he was somewhat caught off guard.
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Still, noting how quickly the mallard returned, it seems he was not that all surprised or put off.
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It is indeed, a very curious relationship between mallards and geese. But, for all the squawks, chases and pecks by geese to their pesky underlings or all the pulled feathers the mallards endure, both species seem to appreciate and benefit from the special attributes of the other.  
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On the surface, it seems the mallards benefit far more from the relationship (in terms of security) than do the geese. One is pressed to figure exactly how geese benefit from the pesky ducks -- other than perhaps, keeping them sharp and on their toes all of the time.
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Then again, in nature, such sharpness and readiness cannot be a wasted thing.  The gosling facing up to and chasing a harmless mallard yesterday is far better prepared to fend off possible threat from a raccoon, fox or coyote than had he not had that early experience.
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And maybe it is that which in itself, defines how geese ultimately benefit from mallards (i.e. preparedness training) -- as the mallards later reap their own rewards in the protection and security of the geese. -- PCA
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Friday, May 29, 2015

Keystone Geese Police, USDA Wildlife "Services" and Tiny Wings of Hope



Mommy and Daddy quickly gathering up babies the other night and moving away from possible threat of raccoon at Reservoir.
Babies gathered in little ball last night preparing to rest as parents keep watch.


The keystone cop-like scenario of "Geese Police" chasing a flightless goose around a lake in Central Park apparently did not occur this morning, according to witnesses. 
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Was Geese Police worn out from the stress of yesterday, requiring an emergency day off? Did they change the time schedule in order to avoid angry, little old ladies? Or, did they finally consult the rule book for goose harassment and learn that molting geese are off limits for reasons of both, futility and animal cruelty? 
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Who knows?
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But, for once the four domestic (flightless) ducks and one-legged, disabled goose (Kaitlin) didn't have to hide in the weeds, while the man from Geese Police paddled around  his canoe in relentless pursuit of a gander who could not fly.
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All great comedies must come to an end. Let's hope this one isn't repeated like dreaded TV reruns.
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As we approach the first of June, those geese who traditionally fly into Central Park for the molting period are beginning to show up. (A period of roughly four to six weeks when geese lose their flight feathers and are incapable of flight.)
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The molting Central Park geese don't constitute a big number -- no more than 35 over the past few years, most of them settling in at the Boat Lake or the Reservoir.
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As of this morning, there were six new geese at the Reservoir and a few new pairs at the Boat Lake.
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Some of the new geese appear very close to molting as the feathers are straggly with some loose ones. I guess that is why these few made it in earlier than the rest. Not all geese molt at the same exact time -- a lesson born out by "Man" the gander at the Boat Lake (and the subject of particular focus by Geese Police) who started the molt at least a week and a half ago.
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Along with arrivals of geese seeking a safe and known place for the molt, USDA Wildlife Services usually also arrives to New York City to map out its roundup and killing locations for hapless, flightless geese around city parks or Jamaica Bay Wildlife "Refuge." (Sadly, one must put quotes around "Refuge" as Jamaica Bay has been the site of hundreds of goose cullings over the past two years.)
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So far, the geese of Central Park have fortunately been spared from such dastardly deeds -- mostly because their numbers are low, but probably more significantly because it would be very hard to pull off the roundups (even at dawn) without being seen by park goers. Many people are already upset with the harassment and egg destruction tactics, which though overdone and cruel (depending on circumstances) are not lethal to the adult geese.
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GoosewatchNYC is the group specifically organized to monitor and oppose USDA goose slaughters around the city. https://www.facebook.com/GooseWatchNYC?fref=ts.  If one lives near a NYC park that has been targeted in the past for goose culls, it is likely to be targeted again.  Please sign up with this site to keep abreast of USDA WS activities in NYC. We are fast coming up on the "busy" time for USDA goose slaughters around the city. Usually such roundups begin in the last quarter of June and continue through the second week in July.
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Though news has generally been frustrating and depressing regarding geese around NYC and even Central Park, there are nevertheless, glimmers of hope.
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That hope is now carried on the tiny wings of four baby goslings who successfully hatched at the Reservoir a few days ago.
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So far, all four hatchlings continue to thrive and appear to be of sound bodies and sharp little minds.
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It was particularly fascinating to witness a particular scene the other night:
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Mommy, Dad and babies were gathered at the edge of the water with the goslings munching some greens growing through the rocks. All of a sudden, a raccoon came wandering along the top of the rocks and Hansel, (the daddy gander) immediately emitted a low, lulling sound ("Uhhhhhooo") which apparently was a warning or directive for the goslings to return to the parents, pronto. Faster than one could blink an eye, all four hatchlings immediately bolted back to the parents and were safely under Daddy's wing.
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Once all four babies were safely and tightly in tow, the family swam away to another part of the Reservoir.
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I found this scene fascinating for several reasons: 
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First, though only two days old at the time, the goslings already understood the warning and directive from parent and quickly responded. Secondly, rather than confronting the wandering raccoon (as they do when nesting), the parent geese chose to gather up the little ones and move away.
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As previously noted, most animals don't seek confrontation if they can avoid it. When nesting, geese don't have the option of moving eggs so they have to be prepared to fight off any potential threat.  But, when having goslings, they choose, instead to move away from threat. This is certainly the more practical and sensible decision under the circumstances.
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Geese are amazingly intelligent and for the most part (except when nesting) peaceful animals.
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It is truly a pity that more people (especially government and park officials) cannot appreciate geese for the wondrous and devoted creations of nature they actually are.
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They should be welcomed in our parks, rather than scorned, slaughtered and endlessly harassed.
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Yes, it was nice today to get a mini vacation from the keystone, Geese Police. That only such peace could prevail -- as it does so in the geese themselves.  -- PCA
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Thursday, May 28, 2015

As Crime Spikes in Central Park, the Geese Are Targeted


"Man." -- Mate to nesting goose, Lady and harassed to exhaustion this morning by Geese Police in Central Park. This, despite the fact he is now molting and incapable of flight.  
Due to rise in crime, police now have to patrol Central Park on horseback.
"Kaitlin."  Goose who lost most of her right leg to fishing line also harassed this morning at the Boat Lake in Central Park.
 
Under Mayor deBlasio, crime has significantly spiked in Manhattan and especially in Central Park. Recent weeks have witnessed muggings, assaults, robberies and even an attempted kidnapping in one of the world's most prestigious parks.
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Nevertheless, while all this is happening, Central Park Conservancy is apparently stepping up its relentless war on geese.
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This morning, an employee from Geese Police was observed in a canoe (with a Border Collie) on the Boat Lake chasing and harassing one goose. The gander in this case is the mate to "Lady" who is still nesting on a nearby rock.  Anyone knowing anything about geese knows a gander is not going to abandon a nesting mate even if tormented to the point of absurdity. But, to make matters worse is the fact that "Man" has been molting for at least a week and a half.  He literally cannot fly anywhere.
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Thus the eyewitness reported the gander "crying" and attempting to fly, but merely skimming the water with Geese Police in hot pursuit -- the employee even swatting the boat paddle at the gander who tried to flee onto a rock.
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"What are you doing?" asked one woman witnessing the scene. 
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"This goose is the most dangerous in the whole park!" the Geese Police man answered.
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"But, I know this goose and he is very gentle!" replied the onlooker.
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The man ignored the woman and continued to chase the then very stressed out and flightless gander.
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At that point, another woman yelled at the man. "What is wrong with you?  Can you not see that this goose is molting and cannot fly?"
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"No habla English." the man shot back and continued to chase the gander in the water.
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Though two different witnesses to the scene were upset, there was nothing either could do. Complaining to Central Park Conservancy via letters or phone calls is completely futile as all are ignored and not responded to.
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There are two other geese at the Boat Lake.  Lady, who was agitated on the nest this morning while her mate was harassed for nearly a half hour and Kaitlin, the goose who lost half of one leg to fishing line cutting into and eventually severing the foot and lower part.
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One might ask, what is the point of harassing a flightless goose, a legless goose and a goose sitting on eggs?
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But, ask all we want, the Conservancy is apparently unwilling to answer for its and Geese Police's actions which this morning, were tantamount to animal cruelty.
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It must be pointed out in sharing these endless stories of harassment, that harassing molting geese goes against all the protocols of this so-called, "management tool."  The supposed "goal" of goose harassment is to "keep geese moving." But, where are geese who cannot fly supposed to "move" to? Chasing flightless geese around a lake is both, cruel and utterly pointless.  As for a goose with only one leg, that is simply adding to the human cruelty that has already befallen and crippled this particular goose.
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When learning of this cruelty and lunacy this morning, I called the Conservancy in attempt to speak with and try to reason with someone in charge.  But I was transferred to voice mail of the Supervisor of Operations where messages are never returned.
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There is no reasoning with a machine.
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And so it is just another day in Central Park where visitors are constantly asked to "contribute to your moment."
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Such a "moment," watching a flightless goose being terrorized around a lake. I can say with absolutely certainty that neither I nor the two women witnesses this morning are "contributing to such moments."
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As for Man being "the most dangerous goose in the whole park," I would love to ask what crimes has he recently committed? Has the devoted gander to his nesting mate robbed anyone? Has he assaulted someone or tried to kidnap a toddler out of a playground? 
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Central Park really needs to get its priorities straight less it become the subject of the 2015 version of, "The Out-of-Towners."
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There are millions of New Yorkers who still remember the bad old days when Central Park was little more than a cesspool for muggings, rapes and robbery.
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Harassing flightless geese to exhaustion and terrorization is not remedy for that. -- PCA
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Tuesday, May 26, 2015

Despite Destructive Actions, Resident Geese Prevail in Central Park


Determined. Despite already losing a number of eggs, Lady continues to (apparently) lay new ones and nest long past original due date at Boat Lake.
A good sign. Day-old hatchlings staying close to parents and swimming in line at Reservoir.
Hope for the future of resident Central Park geese.
Precious little ones already learning and facing an intimidating world.
I am guardedly optimistic about the four newly hatched goslings from the Central Park Reservoir. Not only do they appear to be outwardly healthy, but perhaps just as importantly, their behavior seems in line with what is normally observed in goose hatchlings (i.e. staying very close to and focused on parents and swimming in line with them).
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Sadly, in recalling the three doomed goslings of last year from the same parents, there were concerns about their behavior from the get-go. At first, I attributed the wanderings and seeming lack of focus of the hatchlings to youth and inexperience of the parents. But, when later comparing them to the two healthy goslings hatched later at the Boat Lake, it became obvious that something was wrong from a biological and physical standpoint with the Reservoir babies. Though hatched nearly a month later, the Boat Lake goslings were almost double the size of their Reservoir counterparts and had already developed adult coloring while the lone survivor at the Reservoir was still small and yellowish. A few days after discovering these marked differences, "Remy" the last Reservoir gosling mysteriously vanished never to be seen again. It simply wasn't meant to be that this sad little clutch was to survive.
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Whether the unfortunate demise of the 2014 Reservoir goslings was due to a failed egg addling action or exposure of the mother to damaging pesticides or other chemicals before nesting will never be known for sure.  However, being aware of the "Get the Flock Out" programs and policies of the Conservancy and the general hostility towards geese by the city of New York, it's easy to conclude the deaths of the 2014 goslings were deliberately caused by direct human actions such as egg oiling.
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For their part, though the parents, Hansel and Greta remained dutiful and attentive to their former offspring, I believe in retrospect, that they knew something was wrong from the beginning. They never showed quite the same diligence, discipline and protectiveness towards the little ones of 2014 that they are showing now towards the new clutch. Though they never abandoned their parental duties, it seemed Hansel and Greta were already resigned to the unfortunate fates of their young of last year.
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Of course, in that department -- unfortunate fates of their young -- Hansel and Greta are no different from virtually all the other resident geese of Central Park.
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Speaking of which...
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Although nesting at the Boat Lake nearly two weeks earlier than Greta at the Reservoir, "Lady" is still sitting on her nest almost six weeks later. Either she is inexplicably sitting on oiled, unviable eggs or having already lost a number of eggs, Lady simply laid new ones. If the latter case, she is following the same pattern as last year when after losing 8 eggs, Lady finally and successfully hatched two healthy goslings in late June.
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Another wildlife observer recently reported that Lady's nest and eggs were destroyed last week and the beleaguered goose laid three new eggs a few days later. It's not possible to verify this report, but it seems a more likely explanation than Lady continuing to lay on dead eggs. From past observations, geese are usually keenly aware when their eggs are not viable and shortly abandon them when failing to hatch. (Apparently babies peep and communicate with their moms from inside the eggs shortly before hatching.)
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Adding to the woes of geese and other waterbirds in Central Park is the continuing patrols and harassment of ("Get the Flock Out!") Geese Police.
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Another friend, Liliana reported the following this morning:
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"I was observing five mallards at the Boat Lake when suddenly, the mallards became very fearful and fled.  I looked around, wondering what could have so spooked them and then noticed the Geese Police van patrolling on a pedestrian path close to the water. Apparently, the very sight of the van terrorizes the ducks!"
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Liliana was quite distressed about her observation. -- Especially as the only birds visible on the entire lake this morning were the five mallards, four domestic (flightless) ducks and Lady and her mate, Man.
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"All this for two pitiful geese and a hand full of ducks?" Liliana complained. "Why don't they use the money to go after the real criminals in the park?  The geese and ducks don't rob, assault and try to kidnap children!"  (All crimes that recently occurred in Central Park.)
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I had no words of solace for Liliana as waterbird harassing activities have been going on so long in Central Park and have been detailed throughout this blog to the point of boredom and redundancy.
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Of course we write letters and have complained about such unnecessary harassment and destruction -- destruction that appears hell bent on eradicating every last resident duck or goose in Central Park. (Sadly, our letters repeatedly fall on deaf ears.)
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But, fortunately, Hansel and Greta have a few things to say about all this -- four things specifically.
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And despite the endlessly destructive actions, assuming some or all of these precious little babies survive (and early signs look good) Central Park will not succeed in totally eliminating its resident population of geese.
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Geese always return to the places of their births -- the very behavior that creates "resident geese."  --- PCA
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Monday, May 25, 2015

Defying the Odds -- Baby Goslings in Central Park!


Camouflaged by dense foliage, a newly hatched gosling peeks out from under his mother's wing this morning at the Central Park Reservoir. Below him, a sibling.
Welcome to life, little ones.
 
Hansel was on the war path last night.
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Patiently putting up with pesky mallards the entire time his mate, Greta, sat on her eggs at the Central Park Reservoir, Hansel's tolerance had suddenly run out yesterday.  He aggressively chased all six mallard drakes away from the nesting site last night -- in one case, grabbing a piece of down the size of a golf ball from the backside of one of the drakes and sending the surprised and humiliated mallard flying across the water.  
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Something was obviously up.
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Peering through the dense foliage that has so camouflaged Greta throughout most of the nesting period, I was barely able to make out the tip of her head. But, she was stirring around in the nest as if something unusual was occurring.
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Greta finally sat down very carefully and rearranged her position.  And it was then, I was suddenly able to discern a small ball of yellow fluff peaking out from under one of Greta's wing. And below that, another ball of yellow fluff.
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Greta's eggs were hatching!
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It has been nearly a month since Greta began nesting.
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But, as has been the case with so many nesting Canada geese in Central Park, one could not be optimistic that any of the eggs would ultimately hatch due to the program of egg addling and destruction that has been in place for some years now at one of the world's most prestigious parks.
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This year alone, three other pairs of nesting Central Park geese have already lost all or some of their eggs, including one other goose couple (John and Mary) at the Reservoir whose entire clutch of six eggs suddenly and mysteriously vanished more than three weeks ago.
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At the time, it appeared Greta might have also lost her eggs as none were visible in the nest.
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But, I learned later that Greta was quite adept at hiding her eggs under a "blanket" composed of carefully woven leaves, moss and down feathers. I could not be sure if Greta had lost her eggs and laid new ones or had simply covered and hidden her eggs the day before. -- Particularly as disaster descended on the other nesting goose pair at the Reservoir. (Apparently, the latter was the case as the eggs are now hatching according to the original time frame.)
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But why are Greta's eggs hatching at all, considering the successes of the egg addling program and so many other disappointed geese? Why are they hatching in light of the somewhat heavy raccoon traffic rummaging through the nesting area at night?
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I believe it's because Greta was so well hidden even from the get-go. So much so, I had trouble finding her amongst the thick foliage and dense leaf coverage that camouflaged her. (Photos were nearly impossible to get.)
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But, another saving grace for Greta was the behavior of her gander, Hansel.
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Hansel was quite mindful not to be close to the nesting area during the daytime (when humans are around). Usually he was observed some distance away. While a gander swimming solo in the water is usually a reliable tip-off of a nesting mate nearby, Hansel's wanderings were so far, it made finding Greta all the more difficult -- especially with the fast growing foliage surrounding and hiding her.
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However, once the sun went down, Hansel returned to the nesting site each night to dutifully guard and protect his mate from roving raccoons.  While one can be sure raccoons were aware of the nesting goose (many only being a few feet away), only a very desperate, foolish or starving raccoon is going to take on two angry geese (a topic recently covered in greater detail in this blog.)  In short, raccoons are not stupid and seeking injury. Once stationed and positioned directly in front of Greta's nest each night, Hansel would not budge an inch in the water. He was literally prepared for battle on a second's notice.
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In essence, it is both surprising and not surprising that Hansel and Greta are once again, successful in hatching their eggs at the Reservoir, as they also did last year.
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But, what we have to hope now is that the eggs were not oiled or tampered with at some point during the incubation process as is suspected occurred last year.
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Sadly, all three of Hansel and Greta's goslings perished within a month last year as they failed to grow and develop normally. Such failure to thrive is suggestive of something gone wrong in the incubation process. Certainly, a lack of oxygen (such as occurs in egg addling) would negatively impact the developing embryos.
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The question remaining now is whether Greta was sufficiently "hidden" this year to avoid detection by those employed to oil and render ultimately unviable, goose eggs in Central Park?
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We won't know the answer to that for some time.
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For the moment however, to simply celebrate these new miracle hatchlings and pray to God that His work is not quite finished in protecting this new family.
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In fact, one might speculate, the real work for Hansel, Greta  --and God -- is only beginning.
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Stay tuned.  -- PCA
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Wednesday, May 20, 2015

Sunny -- A Miracle Goose, Defying the Odds


Lady on nest yesterday in what is likely to be exercise in futility (again) in Central Park.
Lady's gander (Man) peering down on nest he dutifully guards almost 24/7.
"Man" taking a few moments from nest guarding duties yesterday to spend time with his son from last year. "Sunny" happily flapped wings in excitement.
Sunny -- the one and only gosling to hatch and survive from last year.
 
Of more than 40 Canada goose eggs laid in Central Park last year, only one gosling hatched to still survive nearly a year later.
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I call him, "Sunny", the miracle (and only surviving) offspring of Man and Lady who are again nesting at the Boat Lake.  Lady has been on her nest for nearly a month now, with eggs due to hatch any day. But, from past experience and Central Park's long history of destroying goose eggs, it's unlikely any eggs actually will.
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Last year, Lady nested three times before two eggs finally hatched in early July. But, Sunny's sibling did not make it back with the family this spring. Either she perished over the harsh winter or possibly mixed into another flock.
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Sunny is usually alone on the lake these days as both mom and dad are busy with nesting duties. But yesterday morning, Dad took a little time from guarding his mate to actually spend a few moments with his juvenile son.
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It was nice to see the two geese together again.  Usually, because he is alone, Sunny is towards the bottom of the goose hierarchy at the Boat Lake as the other six geese are grouped into pairs. But, yesterday both he and dad claimed top billing once again and gently razzed other geese from the area. I strongly suspect and felt that Sunny was happy once again and clearly enjoying the confidence that only a parent can provide.  It was a sweet moment in time.
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Sadly, what does not represent sweet moment in time is the nearly waterbird-empty and desolate appearance of virtually all of Central Park's lakes and ponds.
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It is almost shocking to note hardly any waterbirds at all at Turtle Pond, Harlem Meer, The Pond and very few at the Reservoir and Boat Lake.
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In an 843 acre park, we currently have less than 15 geese and probably less than 30 to 40 mallards.
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One wonders, what exactly accounts for such anemic numbers?
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As far as Canada geese, there is little mystery to why their numbers are so low in Central Park. A nearly year-round program of harassment and egg addling has succeeded in drastically reducing the population from hundreds just a few years ago to less than 15 now.
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Mallards and other waterbirds however, are more questionable.
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One can speculate that in the early spring, other waterbirds might seek more quiet and peaceful areas for nesting than the heavily human populated areas of Central Park. This seems plausible on some levels.
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But, considering that when robust spring populations of geese and mallards did exist in Central Park, few of them actually nested, this theory is seriously called into question. From personal observances, it seems mainly the high status geese and ducks who actually attempt to reproduce.  Nesting is quite taxing on the birds and apparently not all of them are up to it -- even when paired off.
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The other question or more likely theory that pops to mind concerns the long range impacts of nearly year-round goose harassment on the other waterbird populations.
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The truth is, that no species exists in a vacuum as this recent New York Times article illuminates  http://www.nytimes.com/2015/05/19/science/decoding-the-cacophony-of-birds-warning-calls.html?smid=fb-share&_r=0.  "Alarm calls" of one species of bird will impact, not just other birds, but apparently even other animal species.
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Thus it is difficult to think that deliberately causing threat, fright and destruction to Canada geese specifically would not also impact and stress other birds in an area. -- Especially mallards as they generally like to congregate around geese presumably for the extra measure of security and early warning system of danger.  When geese send out distress calls, other birds listen. (I observed that personally in 2010 when geese were harassed at Harlem Meer by "Geese Relief."  The distress honks of the geese incited all the other waterbirds on the lake to fly out with them. Those included, mallards, shovelers, coots and even the one swan who was there at the time.)
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In essence, though we might attribute some of the low number of waterbirds in Central Park presently to be related to natural nesting behaviors, this fails to represent the main explanation for nearly bird-empty watercourses. Rather, continued harassment, egg destruction and general depredation against migratory birds across the country appear to hold the greater validity for disappearing bird numbers. Hundreds of thousands of migratory birds of all types are in fact, killed throughout the country every year under special "depredation permits" issued by our government (including 92,000 Canada geese in just the past two years).  This, despite so-called, "protections" under the Migratory Bird Act Treaty of 1918. Shot and gassed: Thousands of protected birds killed annually | Reveal.
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In New York City alone, more than 5,000 Canada geese have been captured by USDA Wildlife Services since 2009 and either gassed or slaughtered.  https://www.facebook.com/GooseWatchNYC/photos/pb.175344192544178.-2207520000.1432141782./819033344841923/?type=1&theater 
(This number doesn't even take into account the thousands of eggs smashed or prevented from hatching in places like Central Park.) 
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One needs to consider the impacts of such destructive policies across the board, not just on Canada geese, but all other waterbirds who routinely congregate with and around them. Are we seriously heading toward waterbird-empty parks, lake and ponds? It is surely beginning to appear that way.
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With all these grim realities in mind, it is small wonder to consider Sunny the "miracle" goose of Central Park.
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The question is, will he be the last to ever successfully hatch there?  -- PCA
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