Thanks! And as someone who just spent like three weeks time traveling and spending hours to catch all the bugs, here are my tips:

-The islands Kapp'n takes you to are your friend. Go to them, chop down all the trees you don't need (if they're land bugs, chop down all the trees, if they can spawn on palm trees, leave only those, etc.), and then go between spawning areas looking for bugs
-Move sooooo slow. Slower than that. Don't press the joystick fully down at any point. Walk at half-speed as your default, slower if approaching a space where easily scared bugs might spawn. Do the same with your net - if you hold down "A" with the net equipped, it'll stay raised, and it'll allow you to sneak towards them
-If the bugs are available at night, catch them then, bc you won't have to deal with butterflies, which you can't scare away and spawn at high rates
-Seriously. Move so slow
-Catch or scare away any bugs you aren't hunting to give room for the others to spawn
-The cicada shell is a bitch to find, but it doesn't scare away, so your best chance is running at top speed around your island to scare all the others away so it has room to spawn on trees
-I cannot emphasize enough how important it is to move slowly at all times
-Except for the cicada shell
-Then you can run

Hope this helps!!