The breathtaking vision of the Brown Goshawk

A surprise visit from a visionary bird.

Brown Goshawk – Accipiter fasciatus. Source: Tony Ashton eBird

One darkening dusk as I sat quietly in the forest on Budawang, Yuin, country, I heard a swoop no louder than a breath.

I had that feeling of being stared at.

I looked up. On the branch above me, a powerfully built Brown Goshawk looked back at me with fierce yellow eyes.

Then the Goshawk flew west, fast and silent, without a wing flap, shooting between the trees of the darkening forest.

My heart beat hard. For some time, my skin and hair tingled with the feeling of the Goshawk’s eyes on me, even though it was gone.

It’s hard to imagine what it must be like to see like a Goshawk.

They can probably see at least one million colours, 100 times as many as what you can see. They are tetrachromats, which means they have four types of colour receptors in their retinas. They might even have five.

Most people have three kinds of cone cells, but some humans have an extra one, like Sydney-born artist Concetta Antico. She describes growing up with hyper-charged colour perception, “high on life and the beauty that’s around.” She can tell when her daughter is sick because her skin colour changes. She sees an extraordinary range of hues within a single colour like green, or in drops of rain.

Birds, like most animals, can perceive UV light. They see UV patterns on flower petals. They see a wild variety of colours in other birds’ plumage. Some raptors can see the trails of urine left by their prey. Migrating birds have quantum vision that can perceive the Earth’s magnetic field and the stars’ celestial patterns, helping them navigate.

Raptors have the highest achromatic (seeing greys) and chromatic (seeing hues) spatial resolution of all animals – meaning they are able to sharply see the smallest thing, even if it is blended into the background.

Brown Goshawks are swift, precise, and deadly hunters.

They fly fast through the edge of a forest, dashing suddenly out into pasture to seize small rabbits. They snatch Crimson Rosellas out of the air. They wait on a perch, then plummet to grab starlings, swallows or lizards. They pounce on grasshoppers on the ground.

A third, or even half, of the time they attack, they succeed.

They can see fast. As they fly fast, they can manoeuvre and see visual details in vivid colour, with great accuracy, quickly through space and time, with no blur.

That’s how my Goshawk was able to fly west so fast through the twilight forest without hitting a branch.

The same night I saw the Goshawk, around the same time, my friend, who was sitting in another place in the forest, also got a visit.

That bird was onto us.

Thank you to my friend Erik Petersen who reminded me this week that climate campaigning is only sustainable if you stop often to appreciate birds!

Kathryn