Thursday, June 10, 2010 7:09am CDT

 

52 degrees  Cloudy   Wind NE 3 mph

 

It is a cool, cloudy morning that promises rain for the loons this morning.

Then later tonight the rain may become very heavy with the chance of thunderstorms lasting into Friday morning.

While rain sends us humans running for cover, it does not really affect the loons at all.  Water?  Who said water?  That is where we live!

The only concern would be if the storms became severe tonight.  There is apparently not much chance os that happening this morning.  But if there are very high winds or especially hail, that would not be the most pleasant for the loons.

I have watched them sit through hailstorms in the past with hail bouncing off their backs and their heads.  But they never moved off the nest!  It was as if they knew that they could survive the hail but that the eggs never could survive being pelted by hail.  And so that sat on the eggs, ever faithful.  Ever vigilant.

But this morning, the big question is not the weather.

The question is if the egg on the nest will hatch.

Today is day 36 and day 34 for the two eggs.

I have to be honest with myself and with you that we are now at the point where it becomes very questionable whether or not this second egg will hatch.  It is impossible to tell whether it is the 'day 34' or the 'day 36' egg which is still on the nest.  But whichever one it is, we are now moving rapidly beyond the window of time in which we would expect it to hatch successfully.

It is not time to give up on it yet.  The loons have not given up.  But as time goes by, it becomes less and less likely as to whether or not we will see a new little loon chick this year.

Some have asked how long they will sit on the egg even if it is not viable.  There are a couple documented cases of long term sitting on eggs that did not hatch.  One was where the loons sat for 66 days and the other documented case was where the loons sat on eggs for 74 days.

These times are unusually long.  But they illustrate how long a loon will potentially sit on an egg that does not hatch.

Normally something would happen to an egg long before they sat that long.  The most likely scenario is that some predator would take the egg before the loons sat on it that long.  But they will sit for a long time trying to hatch that egg.

This fact alone argues that loons may not be able to feel or know if an egg is viable or not.  Once again, there is just so much that is not known.

The most common predator of loon eggs by far are raccoons.  But there are numerous other predators including skunks, mink, eagles, crows and ravens, seagulls and who knows what else.  The longer a loon would sit on eggs on a land-based nest, the more likely that it would be discovered by a predator.  And the predator would scare the loon off the nest and eat the eggs.

There are cases of loons attempting a second or even third  try at nesting if they lose the first nest.  But second and third attempts are usually less successful than the first attempt  And then the calendar starts to work against them at some point.  A very late nest means that the chicks do not have time to mature before it is time for them to fly south.  And they risk being caught in the approach of winter and their lake freezing over before they are able to leave to fly south.

Here is the most likely scenario of what will happen if this remaining egg does not hatch in the next few days [ there is a possibility of that happening although it is rapidly becoming a slim possibility].

At some point, in consultation with the DNR and other experts, we may remove the egg from the nest.  That will normally break the bond that the loons have with the nest and allow them to get on with their lives and to have a somewhat normal summer - albeit one without chicks.  By taking the egg, we are simply duplicating what would normally happen in the 'wild'.

The advantage of building an artificial floating platform like this for them to nest on is that it protects them from predators as well as rising or falling lake levels.  However, that is ALSO the disadvantage of a nest like this - it protects them from predators who would eventually take the egg.

By taking the egg, we are simply duplicating what normally happens in the wild.  Just a different 'predator'.  A human one.

However, having said that, NOTHING will be done without the approval of the DNR and the consensus of wildlife experts.

Some have asked whether that has ever happened before with this particular nest where an egg did not hatch.  The answer is yes.  On two occasions.

Over the course of the years, this nest has been amazingly successful in hatching and fledging loon chicks.

But the very first year that loons used this nest, they laid two eggs but neither one of the eggs hatched.  The loons continued to faithfully sit on the eggs day after day.  I would have to look back at my notes to remember for sure how long it was, but from what I remember it was well over two weeks beyond the expected hatching date.

Then something happened to the eggs and they abandoned the nest and got on with their lives.

I did not personally see what happened to the eggs so I cannot definitively say what happened.  But when I came home at the end of the day that they abandoned the nest, one of my neighbors asked me if I saw the eagle harassing the loons in the morning.  I had not.

My neighbor told me that all morning the eagle had been flying over the nest and dive bombing the loon.

So we can only assume that the eagle ultimately took the two eggs off the nest.

The second instance was the year when one of the eggs hatched but the second egg did not.

In that case, we left the egg and the loon continued to come back to the nest to sit on the egg.  And unusually, the chick also spent much of its time on the nest as well.  It was wonderful and very enlightening to watch the chick grow during the first two weeks or so after it was hatched.  But it also was not the norm and not what that chick needed.  That chick was not a creature of nest or land.  It was a creature of the water and it needed to be about learning how to survive on and in the water.

So after about two weeks, we took the egg off the nest.

That broke the bond and almost immediately the loons moved on with their lives and the important task of teaching the chick all that it needed to know to survive.

So there has been experience with eggs not hatching on this nest.  Fortunately however, almost every egg laid here has produced a chick.  But that does not look like it will be the case this year, for whatever reason.

Overall, in studies conducted in the wild, each nest successfully produces only 0.62 chicks each year!  So the success of this nest and the loons on this nest have been amazingly successful over the years.

Even though there is a relatively low production of chicks, loons are very long-lived birds so they have a longer opportunity to reproduce themselves.  No one knows for sure what the longest is that a loon can live.  But it is felt that they live at least 25 to 30 years, very long for most bird species.

Several have asked if a loon would renest if the first nest fails.  There is a possibility of that as I said before.  But second and third nests are usually less successful than first attempts at nesting in a season.  And there is the danger of a chick not being mature enough to fly south in the fall.

So once again today, we can only watch and wait and observe.  And hope for the best for our loons.

They have patiently waited.  That is the least that we can do.