Brook trout

The Brook Trout is type of freshwater fish in the introduced in. It replaces the Japan-exclusive Herabuna from and.

Donating to the museum
Blathers will give a speech on the brook trout when the brook trout is donated to the museum:

In
"Even run-of-the-mill, common fish are valuable resources, you see. All part of the grand tapestry, wot! We will take excellent care of this fellow, oh yes. You can rest assured. Excellent care, indeed."

Real-world information
This fish lives in eastern North America, in lakes, rivers, and ponds at a high altitude. Some of these fish stray out to sea, but, unlike the salmon, they will not stray far from the river mouth. Despite being named a trout, it is genetically more closely related to the char. The brook trout has a dark green to brown color, with a distinctive marbled pattern of lighter shades across the flanks and back and extending at least to the dorsal fin, and often to the tail. A distinctive sprinkling of red dots, surrounded by blue halos, occurs along the flanks.