Go to a Museum

Visit a museum which has a large nature section - but be ready for many millions of years declared in the information signs. There will also probably be an admission fee, and the general atmosphere may not be what makes Sabbath special - so this idea may or may not work for some!
If you do go, you could make up a nature treasure hunt (if you have kids) to take a picture of things like: the smallest reptile, the longest reptile, something prickly, something pretty, something scary, something delicate, something poisonous, something fluffy, something tiny etc