Sunday, December 18, 2016

Nesting Mill Creek Waterfowl

     One day this past November, I made three stops along Mill Creek in Lancaster County, Pennsylvania farmland to enjoy scenery and wildlife.  Among other kinds of birds spotted along that waterway, I saw a flock of Canada geese, a smaller group of mallard ducks and a few wood ducks at one place, a gathering of gray-lag geese at another stretch of creek, a pair of mute swans near the gray-lags and at least a few muscovy ducks at each of those spots along the creek.  The first three species of waterfowl are native and wild, but the latter three are domestic birds gone feral and living and nesting along Mill Creek.  In fact, all six of those waterfowl species raise young along Mill Creek, as they do along other waterways in this county, and all are permanent residents here, except woodies which migrate south for the winter.
     All these species of waterfowl, both wild and domestic, are built like boats were easy floating and swimming on water.  And they have beauties and intrigues, which add the same to the waterways and impoundments they live along.  And one has to admire and respect the feral birds as much as the wild ones because they are on their own and risk being caught by predators.  The feral species are just as vulnerable to predators as wild birds are simply because they nest in the wild.  The eggs and small young of all these kinds of waterfowl are subject to being preyed on by mink, raccoons, great blue herons, hawks and other kinds of predators.
     The young of all these related waterfowl species, and other kinds in their extended family produce young that are fully fuzzed, open-eyed and alert, and able to get their own food upon hatching.  They also have webbed feet for easy swimming.         
     Canada geese and mallards hatch young in grassy nurseries on the ground near water.  Each pair of geese and mallard hens brood their young, lead them to food and warn them of danger.  Canadas also protect their young from predators.
     Pairs of wood ducks return to the north early in March and almost immediately look for unused hollows in tall trees, or empty nesting boxes erected especially for woodies, along creeks and impoundments.  And when the ducklings hatch in those cavities in May, they use their toe nails to crawl up the inside of them and jump out the entrances to the water or ground below.  Each mother leads her brood to invertebrate food.
     The pompous gray-lag geese are originally from Europe where they nest in the wild.  Long ago, some of their population was domesticated and European pioneers brought gray-lags to American colonies to be raised for meat and eggs.  Gray-lags, like many kinds of geese, ingest grass and other plant material, both on land and in water.  And some feral pairs of these geese in local cropland hatch up to six young in a brood in grassy nurseries along waterways and impoundments, just as though they are wild.  And those wild-living pairs raise as many goslings as they can.
     Mute swans are large, elegant birds originally from Europe where they are wild birds.  Pairs of these stately swans were brought to America to be placed as ornamental birds on ponds in estates and parks, and on farms.  There many pairs annually raised up to six cygnets in a brood over the years and many of those young birds escaped captivity.  Today thousands of feral mute swans live on larger waters in Delaware, Maryland, New York State and New England.
     Lancaster County has several pairs of domestic mute swans that raise young on ponds, and other, feral pairs that rear offspring along creeks.  Some of those young swans escape captivity and make a living in the wild.
     Both parents of each pair of mute swans is aggressive in defending its cygnets against predators.  And many pairs of mutes drive away Canada geese, which they consider to be competition for space and food.  Male mutes are particularly aggressive.  They hold their wings up to be more intimidating while swimming in strong spurts in a threatening manner toward their foe.
     Muscovy ducks are from South America and were domesticated for meat and eggs, the reason they were brought to North America.  Wild muscovies are large and black with white trim, but many domesticated ones today have pure white feathering or any pattern of black and white.  Drakes are a little over twice as large as hens, and each muscovy has a partly-naked, red head, with males having much more red skin on their heads than females do.
     Interestingly, some feral muscovy hens in Lancaster County farmland start hatching young late in summer, and even in autumn, on their own along creeks and ponds.  This may be in response to the sun "slipping" south then, triggering muscovies that were adapted to living in the Southern Hemisphere to nest.  The sun "going" south indicates spring in the Southern Hemisphere.  But other muscovy hens apparently adapted to the Northern Hemisphere because they start nesting in May.
     All these species of waterfowl, both native and feral, nest along Mill Creek, as they do along other waterways and impoundments.  And there both the wild and domestic birds are interesting to watch conducting their life cycles in Lancaster County's agricultural areas.  Some day, the feral species may be totally wild in North America.   

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