Vegetarian Birds Turn Carnivorous
March 26, 2015 | by Stephen Luntz
Photo credit: Credit: Matt Watson/ABC. Lorikeets near Brisbane eating meat put out for other birds.
Ornithologists are puzzling over the case of a vegetarian bird that has developed an unprecedented taste for meat. So far, the birds haven't shown any sign of including live animals, let alone humans, in their diet. However, a brightly colored version of "The Birds" may be just around the corner.
Rainbow lorikeets (Trichoglossus moluccanus)are a species of parrot common along the east coast of Australia. Although they have become pests after being introduced into Western Australia and New Zealand, in their native regions their bright colors make them exceptionally popular and it is not uncommon for Australians to leave food and water out in the hope of attracting them to their gardens.
Credit Pamela Rose via Wikimedia Commons.
This is what an individual named only as Bill was doing on his property at Elimbah, north of Brisbane: He was leaving out seeds for the lorikeets and king parrots that inhabit the nearby forests. However, Bill doesn't discriminate by color and also provided minced meat for the magpies,currawongs and kookaburras that also live in the area.
Around seven years ago, Bill noticed that the lorikeets were eating the meat intended for their monochrome counterparts. "At first they went for the seed but then they started chasing the other birds away from the meat, which surprised me," he told the ABC.
Eventually, Bill reported the behavior to Professor Darryl Jones of Griffith University who was astonished. "All animals need protein and it is not unusual for them to like it from a concentrated source," Jones told IFLS. "Even among grianiverous birds such as these they were all fed insects as babies. What is so unusual is that they are eating a lot of it."
Ironically, however, the meat might still be healthier than the sugar-rich treats many people ignorantly offer.
Although many vegetarian animals are known to engage in a little scavenging when short of protein or calcium, this behavior is quite exceptional. The lorikeets are superbly adapted to feeding on nectar, with a truly bizarre tongue evolved for the purpose.
The occasional meaty snack is one thing, but putting in the energy to scare off larger birds requires a serious taste for a food their ancestors haven't been digesting for millions of years. “It makes no sense at all,” Jones told the ABC. Even carnivorous birds can develop fatty liver disease from the minced meat of sedentary farm animals. It's also unclear why species such as Australian magpies, known for striking fear into cyclists, are letting the lorikeets chase them away from their preferred food; presumably the kookaburras were too busy laughing at the lorikeets' clown suits to take them on.
Eating unusual foods can be a sign of malnourishment or ecological displacement, but as Jones noted, “The birds look extremely healthy in those pictures.”
Credit: Matt Watson/ABC
Jones has called for other witnesses of birds engaging in a similar behavior to contact him at firstname.lastname@example.org. He says that since the story first broke he has been bombarded with tales of similar behavior. "I'm looking at working with a vet to study the impact this will have if they get a large portion of their diet from meat." In most cases, however, Jones says wild birds get only a tiny percentage of their diet from the food humans leave out, adding, "If this is a big proportion I am sure it would be catastrophic". None of the birds are tagged, so Jones says it is not known if the same individuals have been eating meat for a long time, and if the behavior is being passed on to their children. He notes, "Australian birds are famously long-lived and rainbow lorikeets can survive up to twenty years."
Vegetarian Birds Turn Carnivorous | IFLScience