In my part of the river, geese look like the dominant water-bird species. A gaggle of them usually hang around the Riverside Centre by Donnington Bridge, attended by a submissive raft of ducks (raft, team and paddling are apparently the group words for ducks). Geese (the same or different geese?) can also be seen mixing in with the horses on the field across the river.
There are goose colonies at other points on the rivers too: on the Thames around Iffley lock, Christ Church Meadows, Oxpens Meadow and Port Meadow; on the Cherwell around Wolfson College and the Cherwell Boathouse. They’re said to spend more time on land than in the water, but aim to have access to water. Apparently they like open spaces where they have a good chance of seeing predators in time. The two together perhaps help to explain these choices.
The geese themselves are a mixed bunch. They include Greylag geese (brown bodies, white backsides, orange bills) and Canada geese (black and white heads with black ‘chinstrap’ markings). The RSPB notes that these two are often found together. It pronounces them ‘semi-tame and uninspiring’ (you need to be wilder in manner to appeal to the RSPB). Then there are white geese, descendants of domesticated geese, bred for colour. The RSPB doesn’t recognise these as wildfowl at all, though in behaviour they seem just as wild or tame — ‘semi-tame’– as the rest. They all interbreed and there are many hybrids.
Wolvercote commoners were once allowed to keep poultry and geese on Port Meadow. We’re told in the Towpath Walk in Oxford that geese from Wolvercote and The Trout at Godstow used to be led to the river each morning by goose boys and goose girls. I guess these were bred from Greylags. Canada geese (as the name suggests) are by and large an introduced species. James II brought them in to liven up royal parks. Other big landowners also thought them decorative. Hunters encouraged them as game birds.
Geese numbers have exploded as they’ve adapted to urban environments. The RSPB suggests that there are 40,000 breeding pairs of Greylag geese in Britain, plus another 40,000 younger birds and 80,000 from Iceland who come for the winter, a total of almost 230,000. In the case of Canada geese, we have an estimate of growth: it’s suggested there were 2200 to 4000 birds in 1953, increasing tenfold by the end of the twentieth century; the RSPB thinks that now some 62,000 breeding pairs are permanent residents. Together with young birds and others who migrate south from Scandinavia in winter, that makes for a winter population of perhaps 190,000. So almost half a million wintering geese. The white geese, not being reckoned as birds for this purpose, don’t seem to be numbered.
All these geese are said to be creatures of habit, hanging around the same places. Migrants similarly tend to return to the same places, though hanging loose on local settled gaggles.
Of Canada geese, it’s said that they form unstable pairs from a year or so old, but don’t settle down with a mate until their fourth year, then remaining broadly faithful for life, though other dalliances have been recorded. They nest March to May, and incubate eggs for a month. After that they go through a period of moult, when they can’t fly.
They eat mainly grass, up to 3lbs per bird per day, though will eat insects if grass is scarce. They’re happy to scrounge bread from people, and will apparently raid rubbish bins, though I haven’t seem them do that. They live around 10-12 years, though have been known to survive two or even three times as long.
In July, I noticed a lot of splashing going on among goose groups on the river. Looked like some sort of courtship/family/territorial stuff. According to one source: ‘The flapping of wings, as if attempting to take off from the water, is a universal goose sign of “back off, bud.” Conversely, the wing flapping is also a sign of greeting’. Whether the geese knew which was which was hard to say, because all participants stayed pretty much in place.
.Studies seem mostly to focus on one or another variety of goose, yet much of the behaviour described seems comparable. Flocks are said to be characterised by complex social relationships. Pairs cooperate within groups, and protect their young in ‘agonistic encounters’, which encourages enduring bonding. But younger birds may also hang around together, and form subgroups. To what extent the groups we see mixed-age, and to what extent teenage gangs?
There seems to me something almost military about geese. In the case of Canada geese, the neat ‘chinstrap’ headgear reinforces the impression. But I’m also responding to the apparently purposeful way in which little groups of them will patrol bits of river. Groups on the water look like loose squadrons, massing for operations. Which however never materialise.
Ducks mostly seem happy to blend in with goose crowds. They don’t make much impression on the casual observer, in terms of having distinctive behaviour patterns of their own. Like geese it’s said (though I don’t see geese doing this so much) duck couples tend to isolate in the rearing season. One of the pair may guard the brood while the other goes off foraging. The babies are nicely camouflaged for shallow rivers.
Swans are another matter. Swans seem generally much more couple-y than geese, but also more widely distributed along the rivers. One gets the impression that each pair likes to have its own territory.
A report, in the Friends of the Trapgrounds website, on the behaviour of two pairs of breeding swans that I saw on the Castle Mill Stream Walk re-inforces that impression. We had seen a swan on its nest, with a patrolling mate, and another pair with cygnets, along a short stretch of the canal.
It was subsequently reported that the second male had died, apparently protecting his family from some predator, such as a fox. There was concern that the first male might now harass the second family. Apparently he already had form at picking fights. Or perhaps he would take his family north to the trap grounds? Or the widow swan might take hers elsewhere — perhaps Worcester lake?
I have twice come across swan couples with their brood in obscure corners: Kennington Lakes, the abandoned bathing place at Tumbling Bay.
As a friend has observed, birds must have quite different mental maps of towns from ours, treasuring some of the parts we know least.
There are also some gulls on the Thames, though not in great numbers. They skim and dart over the water, snatching small insects. On a chilly, windy day, this can be quite exhilarating to see.
I’ve seen swallows at the same game at the Wolvercote end of Port Meadow – in this still photo, they’re invisible, but in the video version, you can see them darting around.
I’ve also seen herons on the ait at Fiddler’s Island (noted in the Castle Mill Walk post), and on the Thames between Binsey and Godstow: carnivores, intent on the hunt.
My neighbour, a kayaker, says she sees kingfishers on the water, flashing low down under the branches.
Revised because, having written this, I continued to look at goose flocks and decided I had underestimated their diversity: differences of colouring were not gender differences but species differences. I’ve now checked that out, and revised the text accordingly.