The following sounds were used from freesound:

cat_meow.ogg: modified from "Meow 4.wav" by freesound user "TRNGLE" (https://freesound.org/people/TRNGLE/sounds/368006/) licensed under CCBY 3.0. The original audio was trimmed, split to mono, and converted from WAV to OGG format.

cat_hiss.ogg: modified from "catHisses1.wav" by freesound user "Zabuhailo" (https://freesound.org/people/Zabuhailo/sounds/146963/) licensed under CC0 1.0 (public domain). The original audio was trimmed and converted from WAV to OGG format.

small_dog_bark_happy.ogg: modified from "Dog bark2.wav" by freesound user "MisterTood" (https://freesound.org/people/MisterTood/sounds/9032/) licensed under CC0 1.0 (public domain). The original audio was trimmed and converted from WAV to OGG format.

duck_quack_happy.ogg: modified from "Duck Quack - Sound Effect (HD).mp3" by freesound user "Tabby+Gus." (https://freesound.org/people/Tabby+Gus./sounds/515408/) licensed under CC0 1.0 (public domain). The original audio was trimmed, looped, split to mono, and converted from MP3 to OGG format.

chicken_cluck_happy.ogg: modified from "Chicken Single Alarm Call" by freesound user "Rudmer_Rotteveel" (https://freesound.org/people/Rudmer_Rotteveel/sounds/316920/) licensed under CC0 1.0 (public domain). The original audio was trimmed and converted from WAV to OGG format.

ferret_happy.ogg: modified from "Ferret" by freesound user "J.Zazvurek" (https://freesound.org/people/J.Zazvurek/sounds/155115/) licensed under CC BY 3.0. The original audio was trimmed and converted from WAV to OGG format.

mouse_squeak.ogg: modified from "Cartoon - Bat / Mouse Squeak" by freesound user "Breviceps" (https://freesound.org/people/Breviceps/sounds/445958/) licensed under CC0 1.0 (public domain). The original audio was converted from WAV to OGG format.