From what I hear the tarantula is a much rarer find than the scorpion in New Horizons because of the game's coding. The snowflake spawn in the same as the bug spawn. Since the tarantula is only present during the winter, it has much lesser chance of spawning due to snowflakes taking up some of the spawning.
I don't know why they moved the tarantula to winter since they both used to only be exclusive to spring/summer. I guess they wanted the players year round to be able to catch the rarer bugs.
Vaporman87 wrote :
My daughter caught a scorpion, but not a tarantula.
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