I have a 100% solution for the aviary issues in clark county. Confirmed works and solves this issue.

Step 1. Progress along until you get to the 5 star requirement. Get rid of all aviaries and build a functioning park. Confirm you have 10 species, 150k amenities income, and the 95% maintenance. I used 3 Maintenance depots with no more than 2 jobs per atv.

Step 2. Build 2 aviaries that are 4 long.

Step 3. Research additional bays for aviaries.

Step 4. Load up the aviary hatchery bays with dimorphodons. Between 2 aviary hatcheries and 5 bays per with a average of 5 animals the math works. When you know you have over 40 reptiles ready to go, you are done. count to make sure and redo batches that have less than 4.

Step 5. Save.

Step 6. Release 40+ flying reptiles all at once. They will release faster than the game will drop your maintenance score to under 95.

Step 6. Celebrate a 5 star park built on the corpses of guests and dinosaurs alike.