Earlswood Lakes - Friday March 14

 Sometimes birding can be really challenging no matter how many years of experience you can claim. Today I resolved to return to Earlswood to sort out this Herring/Yellow-legged Gull once and for all. The plan was to see and photograph it in flight, and if possible see what colour legs it had. 

It was a bit of a rollercoaster. To start with I established that the two Herring type Gulls on Engine Pool were the same as the birds I had focussed on earlier in the week. They insisted on swimming around for at least half an hour, offering me nothing that would help. If anything the difference between the mantle colour of the two birds looked just as minimal.

Finally they took off, one after another, and I got some shots. The first thing I noticed was that the wing-tip on the potential Yellow-legged Gull did not show enough white in it to support the argentatus theory which I was quite sold on. Depressingly it looked more like argenteus, the British race of Herring Gull.

After about another hour I was walking back to the Malthouse carpark pretty much convinced I had messed it up, and it was just a slightly darker than usual Herring Gull which inexplicably had a more pinkish-red orbital ring than it should have. 

Then I seemed to get a break. The other Gull was standing on the little rubble island, and as I edged forward the "Yellow-legged Gull" swam in and started to paddle. Its legs were definitely yellow (ok a rather greenish yellow) but bang on for Yellow-legged Gull. I admit I was elated. Problem solved, it was indeed a Yellow-legged Gull.

But there was a fly in the ointment. The amount of black visible on my admittedly distant photographs was too little. When I got home I read everything I could but everything  said that Yellow-legged Gull should always have a black band on P5 (the fifth primary counting outwards from the secondaries) and as far as I could tell my gull didn't have that.

Would you believe, my computer has chosen this moment to stop loading any more photos. 

So I'll sign off by saying birding is very difficult and I don't know what I've seen today. I'll post some photos onto my BlueSky account.

@mortonbagotbirder.bsky.social

I now have an answer. I had more or less come to the same conclusion but Alan Dean replied to my request for his input and has confirmed it was a Herring Gull with yellow legs. The critical features were the pattern of P5, the size of the white spots on the closed primaries (too large for Y L Gull), and the extent of red on the gonys (not bleeding onto the upper mandible.) It's been a very interesting and instructive event.

Herring Gull with straw yellow legs (not a Yellow-legged Gull)