I’ve been browsing the new Baker Illustrated Bible Dictionary and came across the article on Peacock which reads:

‘Peacock’ is a traditional translation of the last item in the list of luxuries that Solomon’s ships brought from Tarshish (1Kings 10:22; 2 Chron. 9:21 [e.g., KJV, ESV, NLT]). However, a more probable translation of the Hebrew word tukki is ‘baboon’ (NIV) or ‘monkey’ (NAB). All the other items come from Africa, but peacocks come from Asia. The KJV also uses ‘peacock’ to translate renanim in Job 39:13, but this is probably better translated as ‘ostrich’ as in the NIV. (1285)

Out of curiosity I checked various English translations and found the majority go with “peacock.” Here’s the breakdown of what I found:

Translation

Versions

Peacocks ESV, RSV, NLT, KJV, MSG, Young’s Literal, HCSB, NASB, CEV, NET,   Douay-Rheims, Knox Bible, NRSV, Lexham English Bible, Amplified, CEB
Monkeys God’s Word, NKJV, Good News, REB, NAB
Baboons NIV, NCV, New Jerusalem, Expanded Bible

Bible Dictionary