Opportunistic Tool Use by Two Unexpected Corvid Species

Area of Science:

• Ornithology
• Animal Cognition
• Behavioral Ecology

Background:

• Tool use is a complex cognitive behavior observed in various animal species.
• Corvids (crows, ravens, jays) are known for their intelligence and problem-solving abilities.
• Previous studies have documented tool use in some corvid species, but not extensively across the family.

Purpose of the Study:

• To document the first instance of tool use in Sunda crows (Corvus enca).
• To provide additional evidence of tool use in house crows (Corvus splendens).
• To explore the evolutionary origins of tool use in the corvid family.

Main Methods:

• Observations were conducted at Singapore Zoo in December 2023.
• Individual crows from both species were presented with enclosed food rewards.
• Crows spontaneously used hooked sticks to extract food, demonstrating tool manipulation.

Main Results:

• Sunda crows spontaneously used a hooked stick to retrieve food, marking the first documented instance for this species.
• House crows also exhibited tool use with hooked sticks, reinforcing previous findings.
• This extends the known repertoire of tool-using behaviors within the corvid family.

Conclusions:

• The findings suggest that the cognitive capacity for tool use may be a conserved trait across the corvid family.
• The expression of tool use appears to be influenced by environmental demands rather than solely species-specific adaptations.
• This research contributes to understanding the evolution of complex problem-solving and general physical intelligence in birds.