Why must Otterhounds almost universally be kept securely leashed outside fenced areas?

Answer

Their strong scent instinct overrides recall training instantly.

As scent hounds, when an intriguing trail presents itself, their instinctual focus switches off their ability to hear or respond to commands, making recall training useless in that moment.

Why must Otterhounds almost universally be kept securely leashed outside fenced areas?
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