What is the cause and purpose that some birds have red eyes, such as bird hawks, herons, some ground birds and deep divers? - Quora
![Indian Cuckoo Bird with Red Eye Sitting on a Fence Looking Angry and Searching for Its Prey. Stock Image - Image of white, dots: 199040263 Indian Cuckoo Bird with Red Eye Sitting on a Fence Looking Angry and Searching for Its Prey. Stock Image - Image of white, dots: 199040263](https://thumbs.dreamstime.com/z/indian-cuckoo-bird-red-eye-sitting-fence-looking-angry-searching-its-prey-chocolate-black-coloured-white-dots-199040263.jpg)
Indian Cuckoo Bird with Red Eye Sitting on a Fence Looking Angry and Searching for Its Prey. Stock Image - Image of white, dots: 199040263
![Blue Bird With Feather Head And Red Eyes Stock Photo, Picture And Royalty Free Image. Image 72239869. Blue Bird With Feather Head And Red Eyes Stock Photo, Picture And Royalty Free Image. Image 72239869.](https://previews.123rf.com/images/anjokan/anjokan1702/anjokan170200189/72239869-blue-bird-with-feather-head-and-red-eyes.jpg)