Ferret by John Montroll

Diagrams in Perfect Pets Origami by John Montroll
Folded from a square of French Marble paper

Mink by John Montroll

Diagrams in Favorite Animals In Origami by John Montroll
Wet folded from a square of Kraft cardstock

Otter by David Brill

Diagrams in BOS Magazine 79
Diagrams in NOA Magazine 526
Diagrams in Origami Per Tutti by Guido Gazzera
Folded from a square of Lokta

Sea otter by Makoto Yamaguchi

Diagrams in Fun Origami World by Makoto Yamaguchi
Diagrams in Good Origami (Toyo 4) by Makoto Yamaguchi
Diagrams in The Elegance of Origami by Makoto Yamaguchi
Folded from a square of Octa paper

Stoat by Sebastien Limet (Sebl)

Diagrams in Just a Simple Base... by Sebastien Limet (Sebl)
Folded from a triangle of Duo Thai origami paper