Like other tortoise species, African sulcata tortoises don't have ears. Also known as the African spur-thighed tortoise, this huge animal is very sensitive to any vibrations in his environment, which cue him to the possible presence of predators. Because of this sensitivity, you might think your tortoise "hears" from his responses, but he's reacting to vibrations and not noise.
African sulcata tortoises have a keen sense of smell, their primary method of locating food sources. They consume plant materials and aren't carnivorous. Their second strongest sense is touch, as their skin is very sensitive. Sulcata tortoises appear to have adequate vision, but it's not a particularly strong sense.
If the sulcata tortoise senses danger from a predator, he has several defense mechanisms. Initially, he will retract his legs into his shell and make a loud hissing noise. If the predator persists, or if a person picks him up, the sulcata emits a huge volume of urine.
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