GOOSANDERS or mergansers : Mergus merganser
Confusingly, goosanders and mergansers are really interchangeable words for the same bird, but you are most likely to see the goosander in West Dunbartonshire. And the male and female are so different that they are often mistaken for different species.
Let's explain :
The term Goosander is the name used locally for this waterbird. In some counties, this same bird is called the common merganser. In the UK, merganser instead usually refers to the red breasted merganser which is a very similar, but smaller bird. What you are most likely to see in West Dunbartonshire's waters is the goosander.
The goosander is a formidable diver. You will very likely see them briefly on the surface before disappearing and popping up somewhere else. To actiually see them darting at high speed after a fish such as the Leven, catch it and come up with a trout is an amazing spectacle.
They are common on such waters as the fast flowing Leven where you may see them enjoying the strong current, letting it rush them downstream at speed, and then flying back again. But in mid-summer you are unlikely to see one here. Although they are known to breed here sometimes, they usually move off to more open waters.
Mr and Mrs Goosander consider breakfast on the upper reaches of the Leven. Note how different they look to each other. She to the left. He to the right.
The water in the Leven is low and fish are harder to catch whether you are an angler or a goosander. Here two female goosanders battle it out for a small fish. The one on the left actually has it.
The winning female goosander goes off satisfied.
The RSPB tells us : Goosander nest in holes in trees along the riverbank. They first bred in in the UK in 1871, building up numbers in Scotland and moving south to northern England and Wales. It is now found in the South West too. The Scottish Wildlife Trust adds : Goosanders have their chicks in spring/early summer and usually have between six and seventeen.
Seeing a goosander mum with her young is a treat. They learn to paddle along behind her very soon and some will get to ride on her back.
We would have expected these females to be on a nest in mid May, but three were on a rock in the Leven preening..
This one did some neck stretching. A fish stuck in the gullet? Or just a good stretch?
The goosanders were not seen, at least on the upper Leven, all during June. It is likely that they had moved to calmer water to raise their young. So it was with some relief that they were noticed again in the second week of July.
A female goosander leads what appear to be almost fully grown ducklings in a neat line down the Leven in July. At this stage male and female ducklings have the same plumage. Although small ducklings have been seen here in the past, it is likely that these were raised on calmer water, perhaps on Loch Lomond. Small ducklings can climb onto their mother's back, but this year (2023) this spectacle was missed.
Some preening after some exhuberant hunting.
A posse of nine adolescent goosanders create happy havoc in the fast flow of the Leven in September and then gather for some relaxing preening. You may notice that all have femaie plumage. Are they all hens or simply young fully grown, but with some only getting their striking black and white male plumage in the breeding season?
The Birdwatching website gives us newly discovered insight into this mystery.
It has been discovered quite recently that Goosanders also have a moult migration, yet extraordinarily, it is confined to the males. For many years, it had been noted that the drakes were absent from their Scottish rivers from June to October or so, even where the mothers and broods were feeding, and for many years their whereabouts was a mystery.
It has now been shown that these drakes undertake a remarkable journey, travelling all the way to the North Cape of Norway. Here they mingle with 35,000 other males from other parts of western Europe and loaf about, moulting their plumage.
It is well known that ducks commonly show differential migration, with each gender exhibiting a different migratory strategy – for example
male Smews remain close to the breeding grounds in winter, while in Britain, further away, we see more females and immature males.
However, for the male Goosanders to migrate such a significant distance, leaving the females behind, is of a different order of magnitude.
BIRWATCHING website : https://www.birdwatching.co.uk/features/species/goosander/
BRITISH TRUST FOR ORNITHOLOGY : https://www.bto.org/develop-your-skills/bird-identification/videos/bto-bird-id-goosander-and-red-breasted-merganser
WILD SCOTLAND : https://www.wild-scotland.co.uk/wildlife-nature/birds/goosander
THE WILDLIFE TRUST : An excellent website to aid in identifying ducks : https://www.wildlifetrusts.org/wildlife/how-identify/how-identify-diving-ducks