Some cats have relationship challenges resulting in inappropriate eliminations. The cats may have been introduced to each other too fast, or there might be too many cats in too small of a space with little or no vertical territory. Or maybe the cats simply don’t like each other. Cats sometimes leave calling cards when they don’t feel confident around other cats, or they may be leaving information about themselves for other cats to discover. Poor litter-box management can be a big contributing factor in this situation, as well.
Make sure that there are enough clean boxes in different locations around the house. You want to provide a situation in which the cats feel safe when using the litter boxes. Cats are very good at staking out areas as theirs. If the litter boxes are located in one cat’s particular domain, another cat might be afraid to trespass in order to use the box.
To solve the litter-box problem in a multiple-cat situation, the causes behind the behavior have to be addressed. If your cats are having difficulties with a new cat who has come to stay, reintroduce the cats to each other slowly.
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