Episode 423: Pack Rats and Busy Mice

Further reading: Mouse filmed moving items in man’s shed in Bristol The pack rat: Show transcript: Welcome to Strange Animals Podcast. I’m your host, Kate Shaw. This week I’m sharing a Patreon episode from last year because I have surgery scheduled. Don’t worry, it’s minor thyroid surgery and I’ll be fine, but my doctor said that a side effect might be hoarseness while I recover. Rather than risk sounding like an old frog, and to allow myself lots of time to rest afterwards, I’ve scheduled Patreon episodes for this week and next week. At the beginning of this year, in early January 2024, you may have heard about a man in Wales who had an interesting visitor to his work shed. Rodney Holbrook is 75 years old and a retired postal worker, and at the end of 2023 he started noticing something weird. Things in his work shed kept being moved, and not in a way that suggested another person was getting in. Initially Rodney noticed that some bird food had been moved into an old pair of shoes. This wasn’t just a one-time thing that would suggest an accident, like maybe Rodney had absent-mindedly decided to store the bird food in his shoes, or maybe it just fell there. The bird food kept ending up in the shoes. Other things kept getting moved too. Small items that Rodney had left out while making and repairing things at his work bench kept getting put into a box, like tools and nuts and bolts. It happened almost every night. Fortunately, Rodney is also a wildlife photographer, and he just happened to have a night vision camera. He set it up in the shed to find out what on earth was going on. A mouse was going on, that’s what was going on. This actually wasn’t a huge surprise to Rodney, because years before, in 2019, a friend of his had had the same thing happen. His friend was Steve Mckears who lived near Bristol, England. Steve kept crushed peanuts in a tub to use as bird food, but he started to notice other things mixed in with the peanuts. First it was just one screw, then it was lots more things that he’d left around his shed. He couldn’t figure out a solution, because he always locked his shed at night. As Steve said at the time, “I was worried. I’m 72 and you hear of things going wrong with 72-year-old gentlemen in the mind.” Fortunately, Steve’s friend Rodney set up a camera and proved that there was nothing wrong with Steve’s mind or with the shed’s lock. It was just a mouse who was tidying up. The question is why are these mice tidying up someone else’s shed? Don’t the mice have sheds of their own to clean up? It’s probable that the mice are actually living in the sheds and are wondering why some humans keep barging in every day and making a mess. Rodents of all kinds do tend to tidy up as part of the foraging and nesting process. Sometimes that means moving debris so the animal can find important items more easily, sometimes it means bringing items back to its nest. House mice and rats will steal small items from humans to make nests, like socks and facecloths. Some rodents are attracted to shiny things and will stash them away or even bury them. One animal, the pack rat, is so famous for storing items that we call a person who likes to collect things a pack rat. The pack rat lives throughout much of North and Central America and is related to mice and rats. It’s bigger than a mouse but smaller than most rats, and some species have furry tails like ground squirrels. It builds a den out of whatever materials are available where it lives, and its den is complex and usually well hidden. Desert species like to build under a cactus, while others live in cliffs or among rocks, in abandoned buildings or sometimes non-abandoned buildings, under bushes, in the tops of trees, or even in the entrances to caves. The den can be quite large and contains numerous rooms used for food storage, sleeping, and storing all the interesting things the pack rat finds while foraging. A pack rat constructs a debris pile to hide its den, referred to as a midden. “Midden” is an old-fashioned word used to describe a place where household waste used to be thrown. Archaeologists love middens because you can learn a lot about people by the things they throw away, and other scientists love pack rat middens for the same reason. Some pack rat middens have been discovered preserved for 50,000 years, which has allowed scientists to learn a lot about what plants were growing in the area at the time. Since the middens also contain the pack rat’s fecal pellets, the scientists can also learn a lot about what the rat was eating, how big it was, and so forth. Pack rats especially like shiny objects and will steal from people. In 2017 when historians were restoring an old home in Charleston, South Carolina dating back to 1808, they discovered several old pack rat middens in the walls of the kitchen. The middens contained buttons, marbles, sewing pins, and even some scraps of paper, including bits of newspaper with a readable date from November 1833. But some of the other bits of paper were torn from a writing primer, a book for people learning how to read or write. That’s not much of a surprise until you remember that this was the early 19th century, that the house was owned by a slave trader, and that the kitchen in particular would have been staffed by enslaved people, who were not supposed to learn how to read. Thanks to the pack rats, we know that at least one person was secretly learning how to read and write. I just hope the rats didn’t do too much damage to their book. The pack rat is also sometimes called a trader rat, because it can only carry one thing at a time. If it’s carrying an acorn home and it chances upon a shiny gold ring, it will drop the acorn and carry the ring home. But you wanted an acorn, didn’t you, instead of that ring? As for mice tidying up, we don’t really know why they do it, but it’s probably actually quite common. It just happens at night when people aren’t around, and in the morning they don’t know why all the nails have been moved into the box of nails, but hey, isn’t that handy? It reminds me of the stories of little house spirits called brownies, which were supposed to work at night cleaning and tidying. When the family woke up the next morning, the house or workshop was, ahem, squeaky clean, and all the family had to do was leave out a little cake or cream every night for the brownie. Thanks for your support, and thanks for listening!