Nellie the sea otter is one cup-stacking hotshot.
In this captivating YouTube video, the aquatic acrobat cleverly manipulates a number of colorful cups before striking a pose with her friend, Abra.
The well-trained duo are currently residents at Point Defiance Zoo & Aquarium in Tacoma, Wash.
Today, sea otters are still listed as "endangered" on the IUCN Red List of Threatened Species. The animals -- now numbered at about 100,000 -- are protected by law.
Need more otter-ly cuteness? Click through this slideshow of of otter whelps that will make you weep with happiness: