Would you recognise the call of a red squirrel or Scottish Wildcat?
If not, you'll soon be able to learn it by listening to a special CD featuring some of the UK's most endangered birds, mammals, insects and frogs.
Vanishing Wildlife, which was made by the British Library, hopes to draw attention to threatened species and remind people to look after wildlife.
Among the 31 animals featured is the last recording of a group of pool frogs before they disappeared from the UK.
Other animals featured include the red backed shrike that died out in UK in the 1960s, as well as creatures that have been reintroduced such as white tailed eagle and the capercaillie.
The unusual sounds were taken from a collection from the British Library which has been collecting them for many years. It holds one of the largest collections of nature sounds in the world
Many of the sounds were captured by people who waited in countryside for hours to get the recordings.
Click here to listen to some of the animals featured:
Listen to the bat
Listen to the capercaillie
Listen to the field cricket
Listen to the woodlark
Listen to the otter
Listen to the pool frog