Effectiveness of fladry on wolves in captivity

The technique known as fladry, traditionally used to hunt wolves (Canis lupus) in Eastern Europe and Russia, consists of driving them into a bottleneck formed by 50 × 10-cm red flags hanging from ropes stretched over the ground. The technique also has been used to livetrap wild wolves. The aim of our study was to assess whether 5 captive wolves living in 2 enclosures (120 m2 and 85 m2) also responded to fladry. We found that avoidance was maximal when flags were ≤50 cm apart and their base was at ground level. In these conditions, wolves never crossed red flags (or gray flags of the same brightness) intersecting their usual stereotyped routes (baseline: 4.08 ± 3.11 SD trespasses/min), even when the daily food ration was placed on the other side of them. In contrast, trespasses occurred when inter-flag distances were ≥75 cm or rope heights were ≤25 cm or ≥75 cm. Wolves bit at the uncrossed barriers significantly more than the crossed ones (P<0.02). Our results indicated that: 1) fladry is effective on captive wolves and 2) fladry can be used to confine wolves into limited spaces and to prevent them from accessing food, at least for a brief time. Our study provides additional evidence that this technique has potential for wolf management and to protect livestock from wolf depredation.