They both often share the same lakes and ponds. They generally enjoy the same diet. Both species migrate and both are intelligent and highly adaptable. And though both are remarkably social with humans, these may be where the similarities between mallards and Canada geese end.
Both in personality and lifestyle, the two bird species are quite different.
One of the key differences between mallards and geese is that geese mate for life and both parents raise their offspring whereas mallards are generally polygamous in their affections and it is usually the mother who alone, raises the ducklings (There are, however rare exceptions to this rule. I once noted a mallard pair raising their ducklings together at Harlem Meer, but such is generally an anomaly. -- Never say never!)
Probably because both parents are involved in the protection and rearing of offspring, Canada goose goslings have a substantially higher survival rate than do ducklings. A mallard hen can produce up to a dozen ducklings, but she is lucky if even half of them make it to their first month. Canada geese usually produce two to seven hatchlings, most of whom survive to adulthood if getting through the first few precarious days of life when they are particularly vulnerable to accident or predation.
Geese also appear far better organized and disciplined than are mallards -- even from the moment they hatch from their eggs. Observe a new family of Canada geese and one will note the goslings staying extremely close to their parents, both on land and in the water. A new mallard mother on the other hand, has a job trying to keep all her ducklings together as there is great tendency among the little ones to wander off and explore on their own --sometimes losing sight of their mama in the process! (It is, for example, common every spring and summer to read news stories of rescued ducklings who have fallen through storm drains or gotten themselves into some other precarious situation, whereas such are rare for Canada goose goslings.)
Although Canada goose goslings appear the same (as do ducklings), it is sometimes easy to guess the sexes of goslings by the behavior of the parents towards them. As the hatchlings grow, ganders heap more attention on the males while their female mates appear to spend more time and focus with the girls. Presumably this is to teach the youngsters from a very early age, the roles and duties assigned to and expected of them on the basis of their sexes.
Recently, for example, I arrived at the Central Park Reservoir to find the two girls of Hansel and Greta with their mother, while Hansel was with his son some twenty or so yards away from the rest of the family. This is something observed quite frequently over the past ten weeks since the goslings hatched, prompting me to conclude with some confidence, the sexes of the three goslings. (Already the male of the three has demonstrated protective behaviors most often associated with ganders. He has either been taught these by his father or is imitating them.)
Though it's possible that mother mallards may devote time and focus teaching their female ducklings "how to be girls," I personally have never seen it. From my observations, it seems mama mallards have their work cut out just keeping the family safe and together.
In essence, a key difference between mallards and Canada geese is the manner in which little ones are raised. Exploration and independence seem to be encouraged early on in small ducklings, whereas in Canada geese, discipline, order, devotion to family and sexual role identification are established in the dawning days of the gosling's life. Any deviations from the established protocols among geese tend to be met with harsh corrections and discipline. Canada geese appear to be in fact, the epitome of "tough love."
Speaking of love (and reproduction), this may be the primary way geese and mallards differ. Put simply, when it comes to romance and devotion, Canada geese appear to have it all over mallards.
Love and sex in the mallard world is often composed of "Wam, bam, thank you, Ma' em." A female mallard not already paired up with a male, can find herself victim of harassment and even sexual assault by more than one drake. (A Park Ranger once told me that female mallards are sometimes killed in the spring by pursuit from several drakes. I have personally witnessed aggressive pursuit (and fighting) among drakes for one female and certainly the hens had a rough time of it, but thankfully survived. I suspect this is the reason some female mallards seek to pair up with a drake in the late winter in order to avoid later becoming a victim of spring hormones and "gang rape," so to speak.
Such roughness and "rape" is rarely, if ever observed in the goose world, though it is common for two ganders to fight heartily for the affections of a female goose.
But once the romantic connection is established between a gander and his female love interest, it IS literally, 'til death do part!
Following are just a few of the many examples of devotion and undying commitment observed in Canada goose pairs over the years:
* Several years ago, a nesting goose became ill and perished at the Central Park Reservoir. Her devoted mate searched and called out plaintively for her for weeks. Although other geese arrived at the Reservoir for the summer molt (most of them young "singles"), the bereaved gander chose to remain alone. When the molt ended weeks later and the other geese departed, the widowed gander still remained alone and searching on the water; indeed a sad and lonely sight. (This phenomenon has been observed in other widowed geese, as well.) The grieving process in geese over lost loves is a profoundly long and painful one.
* Canada goose ganders do not abandon their mates even after repeated nest failures. For some years Central Park practiced Canada goose nest and egg destruction. Time and again I observed known goose couples mourn the losses of their eggs. But the same goose pairs would return the following year to try again. Nor do ganders abandon their mates if they suffer injury of disability. There is an older goose pair at Central Park's Turtle Pond who have been together for years -- this despite the female ("Stumpy") missing a foot and not being able to keep up with her mate ("Stanley") on land and in the water.
* Last October during the migration season, a lone Canada goose remained on the water at the Central Park Reservoir long after her gaggle (and mate) departed. It's not known what caused her to be left behind, but for days she remained stoically on the water either waiting for death or for her mate to return. Other skeins of migrating geese arrived and departed, but still the lone goose remained; a forlorn figure under the chilly and foreboding skies. Then, after nearly a week, (when I expected to find her dead on the water), I was shocked one evening to find the loner goose suddenly swimming with a mirror image beside her -- so close were the two geese they almost appeared as one on the water! The image was the very definition of romance as it seemed (following such trauma), the two geese would never let each other out of their sight again. The next evening the two flew out together to presumably try to catch up to their migrating flock many miles ahead. The main thing though was that they had found each other again. A true romance story.
Of course, mallards and other ducks often form extremely close bonds, but I have not been witness to the kinds of undying devotion and commitment one commonly sees in Canada geese. Such steadfast devotion is in fact, rarely seen in so-called, "monogamous" humans.
Although they share certain similarities (and many differences), the relationship between mallards and Canada geese is a curious one. There are times they appear to regard the other as either, "nuisance" or "bully" and there are times they actually work together -- especially to get through a particularly rough winter. Mallards are smaller and faster than geese and during icy times, help to break up small ice patches in the water. Geese on the other hand, (being heavier and slower) help to break up snow on the ground which aids mallards in finding food.
Mother mallards will sometimes seek out a goose family with goslings to roost near with her ducklings at night. (I personally observed this at Turtle Pond seven years ago.) The vigilance and protectiveness of Canada goose parents helped ensure extra security for the mallard mother and her babies.
In essence, though they don't always "love" each other, mallards and Canada geese have worked out a highly beneficial relationship for all over the years. They don't have to love in order to respect and place significant and intelligent value on the company of the other for their own ultimate good.
Both species are unique and special in their own ways -- as is, all life. -- PCA
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