That's likely because you're using the Gemini app which has a tool for image generation (nano banana) - I do my tests against the API to avoid any possibility of tool use.

This question makes me wonder if you one shot each pelican or do you run it a few times to get the best one?

I one-shot. I have a long-standing ambition to have each model generate 3x and then get the model (assuming it's a vision model) to pick the best one.