Yurruga

Yurruga is 43 days old.

Yurruga is a Peregrine Falcon whose parents, Xavier and Diamond, have their scrape on the water tower at Charles Sturt University in Orange, Australia. Soon this beautiful fully feathered falcon will take its first flight out to that world that it is becoming increasingly interested in.

There are, according to Helen MacDonald in her book, Falcon, “60-odd species of the falcon family Falconidae…Those species are subdivided into four groups: the largely insectivorous hobbies, the tiny, bird-killing merlins, the kestrels and…the large falcons which are divided into two groups, the peregrines and the desert falcons.” The Falco Pereginus or the peregrines are fast flying hunters in the open air whose physical traits have developed over millions of years.

In the world of falconry, the female peregrine is called a falcon while the male is called a tiercel. In French, tiercel means a third indicating that the male is roughly 1/3 the size of the female.* This is called sexual dimorphism. Many also believe that the third hatch is always a male, a tiercel.

Yurruga has incredible vision. In The Peregrine by JA Baker, he says, “The eyes of a falcon peregrine weigh approximately one ounce each; they are larger and heavier than human eyes. If our eyes were in the same proportion to our bodies as the peregrine’s are to his, a twelve stone man would have eyes three inches across weighing four pounds.” * White goes on to say that the whole retina of a hawk’s eye records objects “twice as acute as that of the human retina…with a resolution eight times as great as ours.” Helen MacDonald states that while humans have one fovea and falcons have two enabling them to have two images of the same object fused in their brain.*** Humans have three receptors – red, green, and blue but falcons have four. We have three-dimensional colour vision, falcons can see four. In other words, these magnificent slate grey birds with their streaked chests, yellow cere and legs are far superior in their vision than we could ever wish to equal.

Southern falcons, such as Yurruga, are said to have significantly larger beaks than northern birds. Historically it was believed that these evolved for killing parrots. Researchers today are not quite sure of the discrepancy in size between the two geographical locations.

Peregrines also have a tomial tooth. This is a razor sharp point shaped like a triangle on the outer edges of the upper mandible that fits into a slot in the lower mandible. They use this tooth to bite into the neck of their prey to cut the vertebrae killing the bird instantly.

Sometimes Yurruga sits on the ledge of the scrape box with her mother, Diamond, looking out on the family’s territory.

Once Yurruga fledges, her parents, Diamond and Xavier, will teach her to hunt and will supply her with prey until she makes her very first kill. Yurruga will normally leave the parent’s territory after 4-6 weeks of training.

In the image below, you can clearly see Yarruga’s tomial tooth and her large eyes. She looks so much like a falcon today as opposed to a nestling. She is a gorgeous bird. Some viewers and chatters have gotten upset when Yurruga is aggressive with either Diamond or Xavier. Cilla Kinross said, “Shrinking violets won’t last long in the real world.” So true. Sadly, the survival rate of falcons in their first year is low. We know that Yurruga’s brother, Izzi, was thriving and we hope that she will, too.

One last observation. Diamond has been broody lately. She has incubated or fiddled with the eggs on numerous occasions. This could just be hormones or the physical eggs being there triggering Diamond. But, I wonder if she understands that ‘her baby’ will only be in the scrape a little while longer and she wants to ‘mother’?

In the middle of the night, Diamond was looking at her beautiful daughter.

As winter sets in, we are all looking for some good reads. There are many field guides that feature falcons but it is difficult cuddly up with a field guide. Looking at my bookshelf, I can see any number of them. If, however, you are looking for a really good read to understand the cultural history of falcons and their mythology, I highly recommend (and have done so many times) Helen MacDonald’s Falcon. MacDonald is an excellent and knowledgable writer that easily draws you into her respect and love for these birds. If you have exhausted the guides and have all three of MacDonald’s books, then there is another one. It is a small book illustrated by Welsh artist, Jackie Morris. She is incredibly talented. It is called Queen of the Sky and tells about the rescue, rehabilitation, and release of a peregrine falcon in Wales. An enjoyable read. Morris has a great website full of her wonderful animal stories and bird images.

https://www.jackiemorris.co.uk/

Thank you so much for joining me today. Stay warm! and safe!

Thank you to Charles Sturt University Falcon Cam and Cilla Kinross for their streaming cam where I took my screen captures.

*The males are 7.62- 10 cm or 3-4 inches shorter than the females who are 43 to 50.9 cm or 17 to 20 inches long.

** 12 stone is 76.20 kg or 168 lbs

*** The fovea is the tiny pit located in the macula of the eye’s retina. It allows light to fall directly on the cones to give extremely sharp images.

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