Marmots!

We have often enjoyed seeing the "rockchucks" sunning themselves on the "island".  At a distance they are cute!  We weren't so happy after they turned our big woodpile out by the willows into a marmot hotel.  But we finally used up the wood and banished them.  We also have tolerated (barely) them occasionally burrowing under the back porch.  But now they have gone too far!

First, some sobering info about them from Wikipedia:

Marmots reproduce when about two years old, and may live up to an age of fifteen years. They reside in colonies of about ten to twenty individuals. Each male marmot digs a burrow soon after he wakes up from hibernation. He then starts looking for females, and by summer may have up to four female mates living with him. Litters usually average three to five offspring per female. Yellow-bellied marmots are diurnal. The marmot is also an omnivore.

When the family was at the cabin the first part of July we became aware that we had animal visitors with us inside. Mostly, it was mice.  But Marsh and Holly kept hearing sounds of running at night.  And as the family left and the mouse traps caught those offenders, there was still evidence of some larger animal inside the walls/ceiling.  JD found evidence of marmot borrowing around the back porch and tried repeatedly to trap to no avail and to close holes but they were reopened or new ones were dug.  And still there were piles of shredded insulation coming out of a hole in the ceiling in the new basement bedroom Marsh and Holly had occupied.  So we needed to find the hole where they were getting inside the cabin.

We thought there must have been a vent for a fan in the former sauna shower that was giving them a hole through the thick wood foundation plate that sits on the concrete basement walls.  A similar vent cover could be seen outside from the vent fan of the basement bathroom.  So we concluded there could possibly be one under the cement of the back porch.  We began opening holes in the sheet rook of the ceiling where something had gnawed through from the inside.  It was immediately obvious that we were indeed dealing with marmots.  And when we found out that the boxed down area in the corner of the ceiling along the outside wall had recently been built with plywood to cover one pipe, and that the builder had not known about or covered a vent to the outside, we were worried.

We began cutting and taking off areas of sheet rock where we presumed the vent would be.  It turned out we were completely wrong on the location and at last finally found the vent under the area of the clothes dryer upstairs after opening up all of the ceiling.  We don't think we ever used a floor vent but the original builder had apparently thought we might and provided one!

We were not sure if the animal(s) were inside or out. We closed the hole with some plywood and when JD returned the next day, it was obvious some were trying to get out!

So he opened up the hole and left the room closed and worked outside for awhile.  Then he closed the hole back up with a new piece of wood, put in new insulation where he had removed damaged and soiled insulation and went home.  When he returned the next day it was obvious there was still an animal inside.  This is what he saw!

We concluded that marmots had been using the boxed down area as a highway to get into the various floor joist areas, but that for the most part, they had built a nest just above the sliding doors to the mechanical area and then had gone to the other end, down between the wall and under the jacuzzi tub to build a second nest!  The imprisoned creature had obviously been searching for another way out, pulling down insulation, and then fell down to the floor. So he/she gnawed a hole in the sheet rock to access the jacuzzi area! For several days JD went to the cabin to check things. We did not want to leave the vent hole open long for them to come back inside but wanted to allow any inside time to leave. He found evidence that rocks had been moved outside the kitchen porch more than once but also had pieces of board closing the hole gnawed on or moved aside!  Finally after several days there was no more evidence of imprisoned animals on the inside.  When it was time to remove the temporary plywood cover from the hole, this is how the hole had been chewed around from the outside!  They wanted to get back into their plush hotel!  But this hole was then filled with foam insulation and closed with a piece of metal plus plywood.  Hopefully it will now be impossible for them to return.

In the meantime, it was also evident that marmots were continuing to access the area under the kitchen porch.  JD kept filling holes with rocks and sticking them together with construction foam, but new ones were dug.  Then they filled the box around the fans that feed air into the fireplaces with dirt, crawling in that way!

JD dug and cleaned that area out more than once.  We knew that would need to be marmot-proofed!  So he dug a bigger hole and created a larger box that was faced with metal.  Jeff helped him install this.

A metal grate was installed over this fan box so now it should be animal-proof.  

After a week of seeing no further marmot activity either inside or outside the cabin, JD began repairing the sheet rock damage.  Here are the final photos of his hard work with the walls sanded and ready for painting.  Soon no one will know there was ever a problem and we hope there never will be again!

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