Possible Clues:

• How beastly long to fret about 'er
• Semi-domesticated polecat
• Long to be so predatory as this doubler, perhaps, in more than one foot
• Kind of weasel, a rabbit hunter
• Find (out) by persistent investigation
• It's a little long so to worry about 'er
• Small fierce animal - good hunting rabbits
• Search persistently
• Long to be a predator with doubler in feet, perhaps
• It's used to catch rabbits