Walter Woelber Dalquest, Mammals of Washington, Volume 2
“ The water rat is sometimes a pest to the mammal collector for they spring mouse traps set for other mammals without becoming caught. At times the greater part of an entire trap line was thus rendered ineffective by these mammals. Fully adult animals are uncommon in collections for a rat trap or steel trap is needed to take them and these items, when packed on back up mountains to water-rat habitat, are usually set for still larger animals. ”
