Robin Leppitt is three years into a PhD at Charles Darwin University researching the ecology of the Alligator Rivers Yellow Chat, a subspecies of Yellow Chat that lives largely in Kakadu National Park. The Alligator Rivers Yellow Chat was recently classified as endangered, so the PhD’s focus is on why the subspecies is so rare and seemingly getting rarer. Robin recently travelled to the BBO to check out the Inland Yellow Chat, sister to his study species, to try and shed some light on how closely these subspecies are related.

Slap bang in the middle of November of 2019 I decided to take a risk. I needed Inland Yellow Chat feathers and quickly, as PhD scholarships don’t last forever. I needed the feathers to answer one of the questions of my PhD; how closely related are the three subspecies of Yellow Chat, are they even truly subspecies? The answer would be in their DNA, and one way to get this DNA is with their feathers.

I had already collected feathers from the Alligator Rivers Yellow Chat, the topic of my PhD, when I captured them during my field work over the last two years. The Capricorn Yellow Chat (E. c. macgregori), which lives near Rockhampton, QLD, has been the subject of some conservation effort (it’s listed as critically endangered), so lucky for me feathers of that subspecies were already available. The Inland Yellow Chat, despite being the most abundant and widespread of the subspecies, was proving more difficult, as they live in some pretty remote places and due to their relatively healthy conservation status, are yet to be the subject of any dedicated research, as far I know.

The subspecies were split based on some very subtle plumage differences and that they are thought to be geographically isolated from one another, although some recent sightings out of their historical range have cast some doubt about this isolation. DNA can tell us if the subspecies breed with one another, which if they are, means they shouldn’t be considered subspecies. DNA from their feathers could answer this question once and for all.

I needed those feathers, and I needed them fast.

After some hurried permit applications and some frantic budget analysis, I decided I had the funds but not the time (I’m into the 4th year of my studies!) required to jump on a plane to Broome, but I did it anyway. Three solid days of Chat chasing at the Broome Bird Observatory, one of a few hot spots for these bright yellow beauties, was an opportunity hard to pass up.

The typical place in Broome to find a Yellow Chat: open, dry, low samphire and plenty of dust.

In order to take feathers from live, wild birds, you first need to capture them, and for that you most commonly use a mist-net. Despite the fact I have been trained in the use of mist-nets, I had, at this point, never captured birds without the help of a significantly more experienced netter, I had never even set up a mist-net without help before.

Whilst I would be without a top-gun mist-netter, I was not without help. Day 1 saw the observatory wardens Nyil and Jane, Johani, Vaughan and Ronald from the Yawuru rangers (The Yawuru people are the Traditional Owners of the Broome area), some keen birders and me head out onto the semi-salty samphired plains of Roebuck Bay at the crack of dawn.

Wide open plains provide too many mist net location possibilities

Setting up the mist net with warden’s Nyil and Jane and Yawuru Country Managers

An early sighting of a lone male 500m away was promising, so we set up a few nets (easy! Don’t know what I was worried about) and formulated a plan to behave like sheep dogs, trying to herd the bird towards, and hopefully into, the nets.

We got lucky. It turned out there was not one but around 30 to 40 yellow chats nestled down in the samphire. We then got even luckier, by 8am we had netted 11 Yellow Chats, including 10 in the one net, a phenomenal result. After collecting a few of each birds’ tiny breast feathers we let them return to the flock that was still foraging for insects nearby. What I had allowed three days to achieve we had achieved in three hours; I now had feathers from each of the three subspecies – Inland, Capricorn and Alligator Rivers Chats.

Extracting one of the 11 Yellow Chats we caught

A beauty in the samphire, a male Yellow Chat

This also meant that I now had a lot of extra time in Broome that I had not planned for. It was only Tuesday morning, and my flight didn’t leave Broome until Friday. For someone so pressed for time to complete their PhD, this gave me time to catch up on the writing and analysis of which there was still so much to do.

But, as every birder will understand, this was another opportunity too good to pass up. I went birding instead; I nabbed seven lifers (birder jargon for a species you are seeing for the first time in your life), with the highlights being a White-breasted Whistler in the nearby mangroves and an Eastern Yellow Wagtail on the Broome footy oval.

Back at the Charles Darwin University labs we are well on the way to extracting DNA from these feathers and getting them sequenced. This will not only allow me to estimate how long the three subspecies have been isolated, if they truly are isolated, but also how much genetic variation remains in each of the three subspecies, which is important for their long-term conservation.

I have done a few risky things in my PhD and luckily for me, this time the risk paid off.

Thanks so much to Nyil and Jane and Johani, Vaughan and Ronald from Yawuru who were very helpful and accommodating, I wouldn’t have caught so many chats without them. My memories in Broome will be some of the best of my entire PhD.

Herding Chats