Any gull behaviour experts here?

Question

Hello, I&rsquo;m hoping someone who knows about gull behaviour can help me decipher which is the female and which is the male in a herring gull pair, based on their behaviour. 
 I&rsquo;ve been observing a gull family - a pair and their juvenile (I&rsquo;m pretty sure he&rsquo;s the 2023 offspring). They (or rather one adult, whom I&rsquo;ll call the female) hold a feeding territory which encompasses a section of sea wall where I often sit, as well as a flat roof which protrudes onto the beach. The sea wall section includes benches where people frequently sit and leave food, so prime feeding territory. 
 The female is often there, settled comfortably on the roof, coming over to stake out likely looking people or to clean up scraps when people have eaten their lunch and departed. The juvenile is very often with her. He begs constantly, and she tolerates him, just backing or walking away from him, never regurgitating for him that I&rsquo;ve seen (since October) but never aggressive either. She protects him - closely supervising and chasing off any other gulls who fly near, and usually letting him eat. She now usually comes and take food for herself as well, but is still indulgent of him; guiding him (eg to the shoreline to forage), letting him feed first, and tolerating him following her around and begging constantly. 
 
 It&rsquo;s the interaction with her mate that I&rsquo;m particularly interested in. They are obviously a pair - the male will often land nearby and the juvenile immediately runs over begging for food from him. The female will tolerate the male (when she aggressively chases off any other gull), but not too close&hellip; if he gets too near or attempts to feed, she will attack him quite violently, from running at or dive-bombing him, through to grabbing a wing and holding on (eg if he&rsquo;s actually taking some food that I&rsquo;ve offered the juvenile). She will sometimes tolerate him on the flat roof for a brief period, but will then display varying degrees of warning or threatening behaviour until he flies off. This is very obviously different to how she reacts to &lsquo;intruders&rsquo;, though.

The feeding territory is very much guarded and reinforced by the female, whilst the male is generally settled on a nearby rooftop. He will also swoop in to defend her territory, though, especially if, eg other gulls see a food source and start circling - the pair will then drive those gulls off, before he resumes his distant perch. He tolerates the juvenile too (also not regurgitating but just walking or backing away) but if it&rsquo;s just him and the female isn&rsquo;t present, he will try to steal the juveniles food.

I hoped to see some pair bonding behaviour by now (March) which would give me clues as to whether I&rsquo;ve correctly identified the sexes. It&rsquo;s hard to tell which is the larger, as it varies according to their posture. Am I right in identifying them as above, or is it more likely to be the male holding the territory and the female on the sidelines? The one I&rsquo;ve identified as female is the much more &lsquo;hands-on&rsquo; parent, still, and definitely calls the shots&hellip; which I guess is why I&rsquo;ve assumed her sex as female.

Delle M · Answer

Hi, I realise this is very late (and you may have figured it out by now) but I found this when searching for something and wanted to answer anyway. The gull you describe sounds very much like a male, to the point that I'd feel confident identifying it (him) as such! This is very typical male gull behaviour. They are intolerant of other gulls in their space but manage to tone it down for their mate, and during the breeding season the aggressiveness is toned down further by hormones. I studied herring gulls for my PhD and have witnessed the same behaviour many times. I've also seen similar in carrion crows, so maybe it's widespread in the bird class (I'd imagine it's due to a mix of higher testosterone and the larger [albeit subtly, but enough to be intimidating] body size of the male bird). The male invests fully in parenting so you cannot assume that it is the mother doing more of the feeding. If you can ever get your hands on Niko Tinbergen's 'The Herring Gull's World', you may enjoy it. It's old but still relevant.

Allisandra · Answer

Hi, just a few observations about gull behaviour. ( I have a gull that visits daily and has done so for the last 10 years or so. He has a mate and currently 2 youngsters , one of whom he brings with him regularly.) From my experience it is the male that does most of the caring for the youngster when he/ she is big enough to leave the nest. The male is bolder and takes responsibility for the feeding. He will, now the youngster is bigger, tolerate the female snatching some food. In fact he calls to her whilst holding food in his beak. He is the one who regurgitates for the young bird. What really ( apart from size) sets them apart is the noise they make. The female screams( reminiscent of the seagulls in Finding Nemo) and makes a sort of gobbling sound.//This may not exactly answer your query but I hope it helps a bit.