Someone told me that the Lynx thrives well anywhere it lives, but for some reason they don't thrive in Idaho. Is it true?

Whenever someone makes a statement that an animal thrives well anywhere it lives, it reminds me of when a Doctor once told me that every patient that walks out of his office is alive.  Pretty much a person has to be alive to walk out of the Doctors office, and pretty much lynx or any animal will only live or persistent in an area if they are thriving.  We do not have a documented population of lynx in Idaho.  In fact there are very few lynx sightings that have been documented in Idaho in the last 10 or so years, and of those sightings we cannot say for sure if any of them were staying put ("living and thriving") in Idaho or just passing through.  Overall, Lynx populations are considered endangered or threatened in most of their historical range in the lower 48 States, and that is true for Idaho.  Since there are not historical records of population sizes and whether Lynx thrived or persisted well on the Idaho landscape it is tough to say whether the population was abundant or a scattered relic from an ecological friendler time period.   So, yes I guess it is true that lynx will thrive anywhere they live, but struggle anywhere that has marginal habitat for lynx or other ecological factors that limit or constrain their population.  In Idaho Lynx are not thriving beyond very few and rare sightings, nor do we have documentation that we could current support a higher population.