A musician and composer who spent a year recording sounds on his daily walk by a river hopes it will inspire others to "pay attention to what we hear".
Nick Penny, 68, recorded wildlife along the River Nene near his home in Oundle, Northamptonshire. Birdsong has inspired his own compositions for decades.
He believes tuning into sound can also help people see more wildlife.
"We watch screens all the time. It's great to feel the real air and listen to the real sounds," Mr Penny said.
The composer has walked his local stretch of the River Nene for more than four decades and has been recording its sounds for 20 years.
A chance encounter with a kingfisher inspired him to look - and hear - more closely, Mr Penny said.
"The sound of a kingfisher is a very high whistle, almost like a dog whistle.
"It takes a bit of learning, but once you do, it helps you see them because you can immediately look out and you might see it flash by on the river."
The composer, who has presented a programme on the science of sound for Channel 4 and been interviewed by Lauren Laverne for BBC Radio 6 Music's Supernature feature, has published a book about his year recording the wildlife along the river.
In it, he reflects on the importance of birdsong when so much modern life is affected by noise pollution.
Mr Penny said: "It's just such a magical thing, being out in the open, listening to bird song, looking at flowers - and it's free.
"Maybe just sit for 10 or 15 minutes if you can and you'll be surprised how many things might be going on really close to you that you wouldn't normally notice."
Instead of illustrations, the book has a QR code to enable readers to hear the recordings.