Fun with synonyms - “to grab/catch/capture”
From my current understanding, 捕らえる means 'to capture', while 捕まえる is used to mean 'to arrest'. Is this correct? And is 捕まる its passive?
I'll cite some dictionary entries that should give some insight:
Judging from the dictionary entries, these are basically the same, with つかまえる being in the first definition of とらえる. You may notice, however, that these words have alternate kanji, and the choice of kanji can affect the nuance. For example, definition 2 of つかまえる only applies to the other two kanji. So with this particular kanji the two words appear to be more or less the same.
Some question sites have some other interpretations from regular people, though, who have their own insights about the differences.
Like here, for example, where someone offers this distinction:
Basically the distinction is that つかまえる emphasizing that you use your hands or arms to catch something, whereas in とらえる the emphasis is on the capture, and the prevention of escape. とらえる is stronger than つかまえる. For example, you would つかまえる a bug or a small animal, but not とらえる. There's more explanation on that page too. It seems reliable to me.
And yes, 捕まる is just the intransitive verb.
Like many other 漢字 "捕" has different pronunciations:
Both have the same meaning of catching as in "The cat catch the mouse." or "The cop catch the thief."
As a note, とる as "take" is one of these verbs that has many 漢字 with nuance in each use. The main used 漢字 for とる are:
Of course the line is not that clear, and some 漢字 can be exchanged with others depending on the context.