Koi Disappearing from Enclosed Atrium: Identifying the Predator

Koi vanishing from a fully enclosed atrium with a yaupon holly tree suggests a climbing predator. Raccoons are the top suspect—strong, dexterous, and nocturnal. Other possibilities: mink (can enter tiny openings, very quiet), snakes, cats, rats, otters, weasels, or birds.

Immediate Actions

• Secure the atrium: Cover all openings with 1-inch welded wire hardware cloth (not poultry netting). Seal seams with wire lacing. Ensure no digging access.
• Identify the intruder: Look for tracks, scat, or trail camera footage. Each predator leaves distinct signs.
• Reinstall pond netting: Use tight, secured netting to prevent access while you identify and exclude the predator.

Raccoons and most other suspects eat live fish. Electronic deterrents may work for raccoons but not snakes or mink. For a raccoon-specific deterrent, see Walnut Creek Enterprises. Full exclusion is the only universal solution.