Rat nesting in engine bay

Found a rats nest on top of my engine cover a couple days ago. On the bright side, better a rat than a mouse, he was apparently too fat to fit into the engine air filter box or cabin vents(all clean there). Appears he used the inverter as his toilet area though.
I cleaned it all up as best I could and have been leaving my hood open every night the past few days to deter any future occupancy(going to take it in for engine detailing/deodorizing on monday). My last service was in November, so he could've been setting up home anytime between now and then.
I'm guessing he used it as his winter home. Hopefully now spring is here he has moved on.

Now the question is, what part of the car was used for nesting material?


From what I can see the black fabric on the bottom left mixed with the white fluff appears to be the same as the insulating cover on the splash shield directly underneath the engine. The numbered/coloured tags appear to be Wiring harness labels, yet I didn't notice any bits of wire in the nest or any chewed wires that I could see from my inspection, but still a possibility.
Lesson learned, check under the hood at least once a week, and maybe bike to work less and drive more.

 

I rent a basement suite in a house. Parking is outside on paved driveway. It's supposed to rain tonight, so I probably will not leave the hood open. No sign of rats around the house, in the yard. There was a new fence built I n the backyard, and the neighbour was building a new house, doing a bunch of landscaping the past few months so quite possible they disturbed a nest, prompting the rat family to relocate to my prius.
I'll just keep an eye on my car/engine bay, about all I can do.
One of the downsides living in a port city. Immigrant rats.

 

Never seen a rat in my life before I moved to Vancouver 2 years ago. Had one get in my basement suite 1 year ago(different house), tunnelled and chewed their way right through the wall in the kitchen. Much rather have them living in the engine bay than go through that experience again.
Alberta (my former home) claimed for many years to be a rat free province, not sure if that still holds true.