California Condor (Gymnogyps californianus) Fact Sheet: Diet & Feeding

Food

• Mainly scavenge on medium- and large-bodied mammal carcasses (Collins et al. 2000; D'Elia and Haig 2013; Finkelstein et al. 2015a)
• Includes livestock (cattle, horses, pigs, etc.) and stranded marine mammals (esp. during the 19^th century)
• Also, rodents
• Recent years: mule deer and coyotes killed by humans
• Will scavenge on small mammals, if abundant at one site (Birdlife International 2015)
• Prefer fresh carcasses (Snyder and Snyder 2000; Finkelstein et al. 2015a)
• Feed on soft tissues (low in calcium)
• Have high calcium needs (Collins et al. 2000; Snyder and Snyder 2000)
• Actively collect and eat bones and other calcium-rich objects
• Bones from smaller carcasses (rodents)
• Shells and/or shellfish
• Bring trash to nest sites (Finkelstein et al. 2015a)
• Unclear why
• Plastics, glass, Styrofoam, wire, metal

Water (Koford 1953; Finkelstein et al. 2015a)

• Drink, particularly after feeding
• Find water pools in rocks, potholes, cattle troughs, and waterfalls
• Can go a day or two without drinking
• Females fill their crop prior to egg-laying
• Benefit unknown

Foraging

• Search for food
• Circle in flight, singly or in loose groups, several hundred feet above landscape (Snyder and Snyder 2000; Finkelstein et al. 2015a)
• Often watch the behavior of other scavengers to locate food (Snyder and Snyder 2000; D'Elia and Haig 2013)
• Turkey Vultures, Common Ravens, and Golden Eagles
• Do not locate carcasses using sense of smell, as do Turkey Vultures
• Feed in multiple areas, taking advantage of locally abundant food (e.g., due to disease outbreaks) (Snyder and Snyder 2000)
• Not dependent on one feeding area
• Fill crop (adaptation in birds for food storage)
• On average, takes 20 min (range: 10-30 min) (Finkelstein et al. 2015a)
• Do not need to eat every day (Snyder and Snyder 2000; Finkelstein et al. 2015a)
• Must obtain a meal every 2-3 days to maintain their body weight
• Can survive at least 1-2 weeks without food

Group interactions

• Congregate in large groups around food or water (Snyder and Snyder 2000; D'Elia and Haig 2013)
• Feed in groups
• Compete for food
• Dominance hierarchies at feeding sites (D'Elia and Haig 2013; Sheppard et al. 2013; Finkelstein et al. 2015a)
• Among ranks
• Fluidity in social status among middle and lower ranks
• Dominant birds frequently act agonistically to maintain status
• Among age and sex classes
• Juveniles subordinate to adults
• Young males may supplant older females
• Among species
• California Condors generally dominant over Turkey Vultures and Common Ravens
• Typically at top of feeding hierarchy, unless Golden Eagles present
• Golden Eagles smaller but have powerful talons
• California Condors may be excluded from feeding by Golden Eagles
• May give up and leave to find food elsewhere
• May challenge and displace Golden Eagles when very hungry

California Condors often feed together at carcasses. However, these social groupings are emphemeral.

Image credit: © Chuck Bert/Macaulay Library. Use in accordance with Macaulay Library media use guidelines.

Location: California, USA