Black widow spiders normally only live for a single year, but can survive for up to 3 years if kept in captivity. Spiders do not really "hibernate", as the term refers to a state where the metabolic rate slows considerably during the winter weather. Although, spiders do not truly hibernate, they do respond to temperature, becoming dormant and even freezing when the climate becomes cold. However, as they only survive for a year in the wild, the cold temperature does not really become an issue.
If the spider is being kept as a pet, and exhibiting hibernation like qualities, it may either be that they have reached a the end of their life, or they are being kept in an environment that is too cold for them. It may be best to contact a vet or other professional if you are worries about the health of you spider.
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