* Size and Strength: Ravens are strong birds, but a full-grown squirrel can be a tough opponent. While they might be able to kill a young or weak squirrel, taking down a healthy adult is unlikely.
* Opportunity: Ravens are more likely to scavenge on dead squirrels than to actively hunt them. They may also go for sick or injured squirrels that are easier to subdue.
* Availability of Other Food: Ravens will prioritize easier meals, so if there's plenty of carrion or other readily available food, they're less likely to target squirrels.
In summary: Ravens might occasionally eat full-grown squirrels, but it's not their primary food source. They are more likely to scavenge on dead squirrels or target young, weak, or injured individuals.