Sorry to be a bit delayed in getting back to this subject, but to add a bit
to the breeding biology of waterfowl, ducks will often attempt more than
one nesting in a season if they lose their nest to predators. They
undertake what I have referred to as an all or nothing strategy. Like some
other ground nesting birds (turkeys for example), ducks will lay large
clutches of eggs and while they tend to have a high percentage of nest
losses, they also can produce a large number of young in years when they
are successful. Waterfowl biologists consider a nesting success of 25% to
40% as very good and less than 5% to 10% as barely sustainable. Raccoons
and skunks are among the biggest nest predators of ducks in much of the U.S.
The clutch size is usually smaller for the second nesting attempt since the
females don't have much time to build up energy reserves again. Some
females have also been known to attempt a third nesting effort in some
season when predation is high but they lay few eggs and often are
unsuccessful. This is likely due to the predators now having their growing
young and successful ducks off of the nest with their young, so
rather predator pressure may be more intense for these late nesters. Many
will simply give up after a second attempt since they have depleted their
energy reserves or because it may simply be getting too late in the season
to rear a brood for the year. These second and third nestings result with
the sighting of a hen with recently hatched young in July and even early
August when most young are nearly full grown..
During the first nesting attempt, ducks are rather evenly paired off -
there are most often some excess males around so this makes for some strong
competition, but you can see males and females well paired off in spring
when they arrive in Wisconsin. However, for those females that lose their
nest and come back for a second mating they are now overwhelmed by the
attention they receive from all of the available males. It is usually
during these second matings when competition is at its highest since there
now is only one female in search of a mate and all of these unattached
males that give her such extreme attention. This is most likely when the
anecdotes of males mobbing a hen and either injuring or rarely drowning
here occur.
When I worked at Horicon Marsh I would watch for hens flying around in mid
to late May with several males in pursuit. This is not a hard science, but
it can provide an indicator to some degree of high nest predation and nest
loss. In years when we would see several hens flying around with as many
as 5 or more drakes following behind her we knew that there was a
significant amount of nest loss in the area. The actual fate of these and
earlier nestings is always an uncertainty, but fall banding of ducks
provides a good chance to capture a random sample of ducks in an area and
an opportunity to check on the ratio of young to adults. This provides a
good indication of nesting and production success which is why waterfowl
banding is conducted in August when the birds are coming out of their molt
and before migrants begin to infiltrate our local marshes. This way you
know that the vast majority of ducks captured were locally produced.
Bill Volkert
FdL County
On Mon, Nov 9, 2015 at 9:20 AM, Korkor Mary <marykorkor@xxxxxxxxx> wrote:
Bill I enjoyed your explanation, but I gotta tell you⦠watching the
aggressive nature of drake Mallards is not very endearing. I always feel
bad for the females when I see there are a number of males in pursuit. I
have heard of instances where the hens have been drowned by competing
drakes, and often she seems terrified and desperate to get away from the
drake. I know this is a bit of anthropomorphizing but it is what it is!
Nature has a way of making things work, but it isnât always pretty.
Mary Korkor
On Nov 9, 2015, at 8:46 AM, Bill Volkert <billvolkert11@xxxxxxxxx>wrote:
but
Regarding Waterfowl Mating -
Ducks do not mate in the fall, since they would be laying eggs shortly,
they do undergo a prolonged courtship ritual. The annual cycle beginswith
the summer molt. Ducks lose all of their flight feathers over a veryshort
period of time and therefore are unable to fly for several weeks in lateby
summer. As a result the drakes take on an eclipse plumage. It doesn't
make sense to be brightly colored if you can't fly.
They come out of their eclipse plumage in September or early October and
this time of year they have attained their brilliant breeding plumage.by
Ducks will perform their courtship rituals throughout the winter and mate
selection often takes place on the wintering grounds. The female will
return to her nesting grounds, so you will usually see the hen followed
a drake or several drakes during the spring. Watch ducks in flight nextmate in
spring and you will see that more often than not that the hen is in the
lead with one or more drakes following behind.
Competition remains strong throughout the winter and into spring so they
will continue to perform these displays for the next several months in
hopes of interesting a female and holding on to her until spring when
mating and nesting will take place. This is one of the reasons why ducks
have such spectacular plumages as it is all part of the high competition
and long courtship in hopes of attaining a mate.
Bill
On Sun, Nov 8, 2015 at 8:21 PM, Jennifer Ambrose <jenthreat@xxxxxxxxx>
wrote:
Good evening, everyone,
I viewed the ducks with Rita earlier today and posted some of the many
photos that I took at the post below.
If anyone has anymore information about duck mating rituals in the fall,
please pass it my way. I've been continually curious about why they
http://www.birdspazz.com/2015/11/09/hooded-merganser-madness-and-mating-mallards/the fall, like the mallards in the blog, but I can't find much detailed
information.
Birding Network (Wisbirdn).
Thanks,
Jennifer A
Milwaukee
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