A couple of days ago, Nelson resident, Marnie Lehr, took a wonderful picture of a Northern Pygmy Owl eating a robin. The owl ate the robin’s head first.
Below that is a picture I took last August of an Osprey eating a sucker. Similarly, it ate the fish’s head first.
What is the appeal of the head to so many birds? It doesn’t strike me as one of the most tasty bits.
Dick Cannings responds: “I don’t know exactly why, but hawks and owls often eat the head of their prey first. Often, when a male hawk or owl is provisioning a female and/or a family of nestlings, he’ll eat the head (of the bird or mouse) himself and give the rest to the others. Maybe it’s just to make sure the prey item won’t get up and run away?”
The simple question posed above (why do so many birds eat the head of their prey first?) has produced quite a trail of comments and insights from those who held some of the puzzle pieces. Read the comments, below, to follow the trail. It leads to Stan Wallens explanation and remark that (for a bird) eating brains is equivalent to a human eating: “cheesecake, followed by an entire box of sugar donuts.”
The Kootenay-Lake Website offers further pictures and discussion of local owls and ospreys.
Marnie Lehr’s picture of a Northern Pygmy Owl eating the head of a robin first.
My picture of an Osprey eating the head of a longnose sucker first.
Marnie Lehr’s picture is used with permission.
Beautiful picture Marnie! It seems to me that cougars also tend to eat the head of ungulates first, chomping at the snout to get at the brains. One often finds the remains of this activity in the form of snout-less deer skulls. I have always assumed that the brains were very fatty, and therefore the first choice for the hungry cougar. Perhaps the same holds true for our avian friends.
Thankyou Alistair for your assistance in identifying the little owl we found and for sharing your Saturday morning chatting about a variety of subject matters. I much appreciated viewing your blog this evening and enjoying the photos including Marnie’s contribution of the Pygmy Owl she photographed. I have subscribed to your blog and only regret that lack of time prevents me for reading all of the archived blogs in one sitting! Cheers.
I believe that the head eating is due to the high energy needs of the owl. The brain consists of at least 59% fat, 30 protein plus Vitamin A and calcium. In the cold weather the owls usually eats the head and meat. In the warmer weather their eating habits are dependant on food supply and their body weight. Fat and Vitamin A are extremely important for maintaining proper body metabulism.
I believe you are correct, Carol. Muscles contain a much lower fraction of fat than that. Now, combine this with the fact that the pectoral muscles of birds that migrate can metabolize fats directly, and we have fat playing the role for some birds that sugar plays for humans (a human must convert fats to sugars in the liver before the energy is available to muscles).
It may be that for a bird, eating a brain is roughly equivalent to a human eating a sugar donut.
I would add some things to Doug Thorburn’s comment:
Since organ meats no longer form an important part of the North American diet, we tend to forget how much nutritional value they have.
Not only are brains quite nutritious (not only fat, but other essential nutrients), but they are relatively easy to get at through the thinner bones of the skull.
Anthropologists who study human cannibalism have noted that brains, followed by other organ meats, were the most highly prized parts of the human body in most societies that practiced cannibalism.
Animal brains are a favorite food among hunting societies: Inuit hunters, for example, eat the brains of seals they have killed right on the spot, then eat some of the liver. Then they cut up the seal to divide among the people back home. In other hunting societies, organ-meat stew or broiled organ meats are highly-prized foods.
Also, the juncture between head and body on birds is a weak one. Removing the head requires only a quick ripping motion. This leaves an opening into the upper torso, allowing easy access to other nutritious organ meats. No pulling off scads of feathers first.
Sometimes we have the privilege here of watching Cooper’s hawks catch and dismember house finches [and mourning doves] that have come to our feeders. The hawks will sit on an exposed branch right outside our window. They rip off the bird’s head and eat it, open the upper chest of their prey, eat the organs, pull off a little of the muscle meat, and about half the time leave a half-finished carcass with breast and leg muscles pretty much untouched. We’ll find the remnants of the finch’s or dove’s body under the branch; we’ve never found an uneaten skull.
So: it’s not a sugar donut. It’s a cheesecake, followed by an entire box of sugar donuts.