The rats have probably lived in the Githens Acres neighborhood since before the white settlers came. What is now Githens Acres was changed from a typical foothills meets the prairie ( with a seasonal creek) area to a large apple orchard that covered hundreds of acres. The Silver Lake Irrigation Ditch was put in for the various crops in the area, by the various owners - Mr. Githens being the orchard owner. My brother-in-law, Jim, bought his house in the mid-1960s, when Githens Acres was located far north of the City of Boulder, and living in that area was considered "living in the country." Now the neighborhood is surrounded by the City, and the seasonal creek serves as a "green way" for wildlife on the move - coyotes, bears, mountain lions, bobcats, raccoons, and an occasional otter.
In September of 2013, Boulder County (and much of the eastern foothills of the Rocky Mountains) was swept with a huge rain storm that flooded the upper foothills of the mountains, sometimes sweeping towns away. The eastern end of the street my sister and brother lives on was completely washed away; when the water finally dried, there was a crevasse that ran between 6 inches to ten feet wide, and from six inches to eight feet deep. I was staying at Kathy and Jim's house, as they were on vacation. Several neighbors and I noted seeing some large rats in the area, immediately after the flooding. We decided that the flood had brought the rats.
Casting back in time, wending through my memory, I remember that the winter that Kathy and Jim went to Peru (and I stayed at their house), I saw a couple of rats. At that time, Jim had two Samoyeds - Suki, the mother, and Boo, her daughter. Neither one of them reacted to the rats - even though the rats ran into a crack under the concrete steps that led into the house. In any event, I've seen the rats off and on for several years. I spoke to Kathy and Jim about them, but, as they had never seen the rats, they took my stories with a grain of salt. This past summer, after the flood, their next-door neighbor complained about "all the rats" that were around her house and garden. She set out traps for weeks, but only caught two rats, while all the other traps were tripped multiple times.
The day after our first heavy snow, Tuesday, 11 November, Jim saw a rat run across the back patio at his house. During lunch, both Kathy and Jim saw a rat run across the patio. That afternoon, Jim got 6 rat traps - the inhumane kind, which is supposed to kill the rat by breaking it's neck when it takes the bait. (Jim couldn't find anyone who wanted to extend a welcome and re-locate the rats elsewhere - ) Jim baited all the traps and placed them outside. One on either side of the patio doors, one at the rear door to the garage, one at the corner of the garage, and two by the back steps where I had first seen the rats, way back when.
Those suckers are clever and strong. Frequently, the bait is removed, without the springing of the trap. But Jim
has trapped and killed ten of the rascals. While I was making meatballs in the kitchen on Tuesday, I heard a loud clap and about 5 seconds of high-pitched squealing. I peeked out the window and was looking right into the eyes of a large rat - the levered bar of the trap was right across it's neck, and the mouth was partially open with the tongue sticking out. I was certain the rat was dead. A few minutes later, I glanced out the window again, and the trap was upside down and empty - and you could see the butt and tail-wiggles of the critter in the snow, where it had worked to escape. That was pretty amazing. That was after there was a dead rat in a trap on the patio - and I know that that one was dead - it was frozen solid, because I had to keep Rosie from playing with it, and I checked it. Three hours later, Jim was going to remove the carcase and re-bait the trap, but he couldn't find the trap or the rat. We both walked over the back yard and under the trees, and could
not find the trap or the rat. (But I did find a large pile of coyote scat, and a place where a coyote had napped in the sun, so Jim and I think the coyote took the whole kit and kaboodle.) Jim was rather upset because the missing trap was one of the hair-trigger ones that had an extremely powerful snap.
I think the funniest thing that I found was a rat-made slide in the snow. It began under the woodpile under the kitchen window and coasted down about 24 inches to the regular ground level. It had several little twists and turns - just like an otters slide down into a river. One could plainly see the marks of the rats' tails in the middle of the slide, along with an occasional footprint, giving themselves a push... Yesterday leaves had blown onto the slide and it looked as if it were no longer in use. I hope that Jim has caught the majority, or all, of them!