Sunday 10 January 2016

Harriers at the Haven

Happy New Year! Normally it would be time for my new year's roundup but I admit I'm a bit behind on everything. It was a hectic last part of the year with nothing but job drama, then my housemate took the internet a while ago and I won't have it back till Tuesday. I'd like to say that was why I haven't written for a while but actually it's because I've been overwhelmed by everything I've seen and didn't know where to start. That combined with the job drama meant I didn't write. Now that I'm borrowing some wifi I'm going to put a hold on the new year's post until I'm reconnected and for now concentrate on my visit to Titchfield Haven yesterday!

I've been out of touch with bird news without internet but my mum happened to check Titchfield Haven's twitter feed and found out about the Penduline Tits.  Three have been reported since mid-December, starting out at Titchfield Haven, moving to the IBM lake in Cosham, and have now returned to the Haven. Despite the blowy, rainy weather we made our way down there yesterday to find that they were currently at the Meadow Hide.

The hide was much more action-packed than usual, both with people (as we were expecting) and with birds. Later after visiting the Meon Shore Hide, which usually boasts the highest numbers of birds, we found that practically all the islands were underwater, possibly explaining why most of the birds were at the Meadow Hide. There were ducks, Canada Geese and Curlews feeding on the field, and a suspicious amount of fluff floating around a patch of bullrushes just in front of the window, even though it wasn't that windy at that point. The bullrush heads were mostly bare but there were a few that still had a good amount of their fluffy seeds on them, and some birdwatchers directed us to the source of the flying seed, the small bandit masked beauty that was the Penduline Tit!

I would judge it to be about the size of a Great Tit, with colouring that reminded me of a Red-Backed Shrike very much- the brown back, grey head and black mask are very similar and I think the Collins Bird Guide mentions this too. Looking at the picture in that book I think this was a female because it had a small mask, whereas the male has a larger one (which would probably make it less reminiscent of a shrike), and our bird seemed pale while the males are apparently brighter. I believe there are two females and a male about but the other two never showed. Not that anyone in the hide minded because this bird was showing fantastically well, it was no more than 10 metres away and was feeding right on top of the reed where everyone could see, pulling out clumps of the fluff to get at the seed. Cameras were clicking and I have no doubt they got some fantastic photos!

Meanwhile, the rest of the birds were putting on a show too. All the ducks were fully post-eclipse and the drakes were strikingly bright (I don't think I've visited wetland since the tail end of eclipse season where everyone's still looking a bit dingy). Not to mention the mild weather was definetly effecting them and courtship behaviour was breaking out everywhere. We spotted a pair of Gadwalls bobbing their heads up and down, mimicing each other. Clearly their courtship was at an advance stage already because they started to mate on the water, the male grasping the female on the back of the neck with his bill and pushing her under. He mated with her several times, allowing her head to come up to breath in between. Duck mating does tend to look brutal but this didn't seem as bad as what I've heard about Mallard mating (I've never seen it but birds have been seen to die during this spectacle). It was more like the Black Swans I saw at the Haven, written about here. Only no swan is going to have a problem with its head going under, and the courtship seemed much simpler with the Gadwalls.

I haven't extensively observed wildfowl courtship but it does seem like mimicry is common. I saw several pairs of Canada Geese doing this too, and noticed that there is quite a sexual size difference when you see two that are clearly male and female together, the male is definetly a size bigger. One pair had a very flirty male who in between mimicing would hopefully peck at the back of her neck, and I'm sure I know what that meant, but she didn't seem ready yet. Interestingly as well as mimicing each others movements, they would also take turns pecking at the other's feathers. Do geese ever preen each other for courtship, I wonder?

This was all very interesting but an even more interesting thing was about to happen. Suddenly the cry 'Marsh Harrier!' went up in the hide, and a large, familiar sillhouette started to glide over the reeds, followed by another and still another. I saw familiar not because Marsh Harriers are common at the Haven (far from it, I've only seen them there once before) but because I've watched them extensively when I lived in Kent, at reserves like Dungeness and Elmley Marshes, and their shape and flight style is very distinctive. They fly low over the marshes, wings in a shallow V, and you can see their head looking down below the level of their wings, looking for prey. On Kentish marshes a harrier's appearance will cause every bird to go up- wildfowl, waders and gulls- and some to mob the bird and try to drive it away. I've seen this many times, but I've never seen a Marsh Harrier actually make a kill. While they probably do sometimes kill small ducks and waders, usually you see them dropping into the reeds and not come back up, and it can be assumed that they caught a small mammal of some sort, or maybe a frog in the summer.

I say this to try and explain a weird thing that happened when the harriers came: despite there being three of them at once (actually four because an adult male appeared a little later on- we decided it was probably an adult male, an adult female, and their two youngsters), none of the wildfowl and waders on the water or the meadows flew up. It was really odd, as normally a bird of prey sillhouette unsettles smaller species whether or not they are actually likely to be caught by it. The four harriers spent a lot of time circling around and gliding slowly over the reeds (they seem to let the wind take them along before turning around and flying into the wind back over the area to carefully comb it for prey) and it caused practically no disruption, and also none of them were mobbed. Are these birds just not used to harriers, unlike the Kentish birds? The harriers certainly didn't breed in the area and probably didn't arrive that long ago so that was all I could think of to explain it.

The two young birds looked very similar to the adult female in plumage, but you could tell which was which by their behaviour. The adult female kept being harrassed by one of the youngsters while she quartered the marshes. Birds of prey seem to keep bothering their parents for food for a long time, which makes sense as hunting is so difficult and they have so much to learn, and I've seen other species do this with calls. For example a young Peregrine trying to get food from an adult is a sound impossible to miss, it's a continual shrieking that immediately alerts you to the presence of a put-upon adult bird being chased around the sky by an insistant and very noisy youngster! And I've seen a Kestrel being bothered by its youngster, which was the only time I've ever heard a Kestrel make a sound, it was a 'ke-ke-ke' kind of noise (possibly where the name Kestrel came from?) and it was also somehow doing the little begging wing-flutter young birds do while in a glide. (It didn't get any food and was in fact probably hindering the adult's hunting efforts!) The Marsh Harrier youngsters didn't seem to be making any noise, unless it was very quiet, but the one that was bothering the female kept flying just under her and swinging its talons upwards to almost connect with hers. I know that Marsh Harriers sometimes pass food to each other in this way during courtship (never seen it but I'd love to!) where its part courtship feeding and part showing off their flying skills and therefore strength, but it seems illogical that they'd waste energy feeding babies this way. However maybe the mimicing of food pass behaviour was supposed to be a way of showing the youngster wanted to be fed? Presumably it could see the female didn't actually have food in her talons right then, but this was a way of saying 'hey, hunt me something!'

I wondered if there was a bit of hunting teaching going on as well. At one point the female and one of the juveniles were on each side of a small flock of Mallards, floating just above them. The ducks seemed completely unbothered until the youngster made a small lunge towards them and they decided to swim away from the area quickly. There didn't seem to be much intent towards the lunge a far as I could tell, but who knows? I don't know how long Marsh Harriers stay with their parents, I'd love to find out more. They are lovely birds, some of my absolute favourites ever, great to watch and known to fly in almost all weathers. I hope they stick around Hampshire for a long, long time.

How was your 2015 everybody? Stay tuned for my look at my 2015!

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