On the island you can see these for once it does start to rain a slurry of liquid bird poo runs off the cliffs and forms clouds in the sea around.
We get used to it and don't notice the smell but it does affect life on the island. In peak puffin feeding time eating dinner outside can mean a liquid addition to your meal from above. And the rain water collected from the roof becomes what is really dilute bird poo and so isn't suitable for anything other than flushing loos. So a dramatic reduction in seabirds can have a knock on effect on other creatures and ecosystems that are adapted to live on this redistributed energy. You can never look at any one group of wildlife in isolation.
And less poo would remove one of our favourite occupations - spotting pictures and faces in the patterns from above!