November 24, 2019: Are the Bears in Bed?

Several people have asked whether it's safe to put out bird feeders at this point due to the unusually cold weather we've had.  NH Fish and Game recommends not putting feeders up until December first, or "the onset of prolonged winter weather."  The definition of prolonged and winter weather is open to interpretation, but I lean towards it meaning lasting snow on the ground.  Bears do not go into hibernation because it's cold, but rather because their food supply is dwindling, and this year there are lot of acorns still available.  And even with snow on the ground bears can be on the prowl, and I've seen plenty of tracks in the snow.

These tracks are from last year on November 25 -  I have seen bear tracks as late as December 1st.

So use your best judgement regarding the feeders, and know that if you wait, the birds will be fine.

You don't want to see this at your bird feeder.

I used the term "hibernation", which though accepted by biologists, is not technically correct.  True hibernation is a state of such deep sleep that an animal cannot be woken, and as some people have been surprised to discovered, this is not the case of bears.

I recently heard an "Ask Sam" report on our black bears which provided some fascinating information.  For one, our bears will lose 25% of their body mass over the winter, burning some 4000 calories a day during hibernation.  They also have a remarkable ability to recycle their urine and their bones - if humans rested like that they would lose an incredible amount of bone density - except they would first die in just a few days from urea poisoning.

Scientists are studying these abilities to look for new ways to treat osteoporosis and kidney disease in humans.  You can read about the bear's unique ability to survive hibernation here:  Hibernating Bears Emerge with Hints about Human Ills, Elisabeth Rosenthal, April 21, 1992.  Oh, and don't forget, while female bears are fasting for months at a time, they are also gestating their young, which were impregnated way back in the spring and have been held at bay waiting for winter.  Multiple eggs may have been fertilized, but the number that are allowed to become implanted and develop into embryos depends on how much fat the mother was able to put on during the fall months.  Simply amazing stuff going on in that animal.

It has been over two weeks since I've seen the remaining loon parent and the juvenile (Davidson) that has been with her all summer;  this was my last sighting on November 5th:

Davidson and mom on November 5th.

I shouldn't do this because it's only speculation, but I'm going to say that Davidson and the parent left the lake together.  This is based on the fact that they were always together, and suddenly they were both gone.  Of course it's possible that the parent left Davidson, and in short succession Harley left as well, leaving Davidson alone on the lake - this just seems less likely.  Also, I've seen the remaining juvenile behaving very much like Harley has during the late summer.  So that's my best guess, and pending any additional data I'm going to record Davidson as having fledged on November 5th and we'll see about Harley.  I haven't seen him/her since November 17th but I'll wait another week to see what happens.  Marge Thorpe did see what was probably Harley practicing take-offs and landings on the southern end of the lake on November 18th, so he's getting ready.

Even if all the loons are gone at this point there are still plenty of birds on the lake.  We had the northeast conference of Mallards United spending a few days on the lake.

Meet and greet social hour.

The welcoming committee.

At one point I counted 63 ducks, and I'm sure I didn't get them all.

54 mallards in this picture,

and more coming in to join the party.

They would tuck right up against the edge of the ice that formed along the shore to search for food on the bottom.

"Bottoms Up" has a different connotation for ducks.

Back on August 19th I noted the acorn pip gall wasps that were attached to the many acorns landing on the dock as well as in the water.  This large collection of acorns is now on the bottom of the lake and appears to be a major draw for the ducks.

Acorns are highly nutritious and sought after by animals of all shapes and sizes, from mice to bears.

One study of 40 mallards performed in a bottomland hardwood forest in Texas [Ref:  Miller et.al via USDA Forest Service] found that over 89% of their diet was acorns, so they seem to take good advantage of this food source when it's available.

I'll close with evidence of one more bird active last week, one which also partakes of acorns, though only the land-based ones.

Tracks from a turkey trotting through the early snow.

The tracks of turkey are pretty easily identified based on their shape and size.  Hmmm, that makes me think of Thanksgiving.  I hope you all have a great holiday with family and friends!  Happy Thanksgiving!