Wild Animals In Road Post Mounted Sign - 551 R2/RA2 (Face Only)Although the sign shows a deer, the sign to diagram 551 is to warn drivers that there is likely any wild animals in the road ahead. When possible, specifying what type of animal should be done through the use of; 550 for wild horses; 550. 1 for accompanied ridden horses; 550. 2 for horse drawn vehicles; 551. 1 for migratory toads; or 551. 2 for wild fowl ducks. This sign should only be used with a plate For and the distance the driver should be wary.