Questions & Answers about Я вижу здесь медвежий след.
Since вижу requires the accusative case, why do медвежий and след look like they are in the nominative?
The verb вижу does trigger the accusative case here. However, след is an inanimate masculine noun. For inanimate masculine nouns, the accusative form is identical to the nominative. The possessive adjective медвежий simply matches the noun it modifies, so it also keeps its nominative-like form.
If I saw a bear's paw (лапа, feminine) instead of a track, how would the adjective change?
It would become медвежью лапу. For feminine nouns in the accusative case, this type of possessive adjective takes the -ью ending. Notice the soft sign (ь) that appears in all declension forms of these adjectives except the masculine nominative and inanimate accusative.
Could I say след медведя instead of медвежий след?
Yes, след медведя (track of a bear) is grammatically correct and means the exact same thing. However, using possessive adjectives like медвежий, собачий (dog's), or волчий (wolf's) is extremely common and natural in Russian when talking about animal body parts, tracks, or habitats.
How would this sentence change if I wanted to say 'I don't see a bear's track here'?