Intelligent crows seek to eat poisonous sugar cane toad meat

Crows are almost the only animals that can attack and tear the cane toads that are still immune to their dangerous venom.

Crows in Australia found a way to eat sugarcane without fear of exposure to their toxins, Science Alert reported yesterday.The cane with the scientific name Rhinella marina , which is a native animal in South America and Central America, was introduced to Australia in 1935 to control native beetles that destroyed sugarcane fields.

Cane can eat many species, but very few animals can eat them due to poisonous glands on the toad body. They quickly exploded in numbers and distributed throughout northeastern Oceania. Wherever sugar cane toads appear, indigenous populations rapidly decline in numbers due to competition of resources and most of the cane toad meat is poisoned.

The crow knows to choose the correct attack location to avoid contact with the venom of sugar cane toad.(Photo: National Geographic).

Their most notable victims are bag cats, salamanders and several species of snakes that have been completely eradicated in some areas. However, crows have learned how to eat sugarcane toads and still avoid most of the poisonous parts.

The large parotid glands in the neck and the shoulder of the cane toad carry the greatest risk. When disturbed, sugarcane toads produce white milk toxins from these glands. Any contact with toxic substances will definitely kill. In many cases, predators die before even swallowing sugar cane toads.

Crows avoid contact with toxins seeping by grabbing the limbs or eyebrows above their eyes, avoiding touching the body. This clever bird knows how to push a toad backwards, sometimes repeating many times if the toad tries to run away. They also know that they should eat parts such as fleshy legs, tongue, intestines, and how to separate parts from the toad.

The Torresia crow (Corvus orru) in the picture took nearly 40 minutes to tear up the victim near Kurwongbah Lake north of Brisbane, Australia, according to photographer Steve Wilson, who witnessed the incident. It cleverly avoids white toxins in the parotid glands of cane toads. During the process, the other crows nearby stood still and quietly watched. Birds can tolerate toad venom better than reptiles and marsupials, most likely due to the genetic exchange between Australian and Asian birds that evolved with toads.