What will this robin do next with that tissue? "Robins are used to how grasses and other natural fibers behave when wetted and then dried out," explains Laura Erickson. "These may shrink, but not much; human-made items can behave entirely different. When tissue paper gets wet and then dries, it can shrink and then stiffen, or it may disintegrate altogether—which makes tissues a poor choice for nesting material. Robins have settled in near people for so long that they've adapted to our ways. This one's nest won't be compromised if it uses a bit of paper in it, but please don't take this as evidence that because robins use tissue in a nest, it must be okay."