How can I call a random image from an updating Unsplash Collection?

I am creating a website that shows a random picture of a Guinea Pig. I am constently adding pictures, and I'm storing all the photos in an unsplash collection: "unsplash.com/collections/09ARrXAI2Sk/guinea-pig"

I am wondering if I can choose a random image from this collection. This is my HTML code:

<img src="https://source.unsplash.com/collection/09ARrXAI2Sk/1600x900">

Can someone tell me how to do this correctly?