Cycling through Griffith Park off the Mobhi Road, after a walk in the nearby Botanic Gardens, a flurry of wings and a flash of colours attracted my attention. Three birds came down with a splash into the Tolka.
You don’t need to be any kind of expert to identify the Mandarin Duck, especially the males and that’s what two of those birds were. The dowdier third one was the female.
I have often noted two male mallard ducks peacefully accompanying one female and wondered whether they had a menage-a-trois going or what the arrangement was. But there was nothing like that going on with the Mandarins as the males made clear quite quickly. After briefly circling around one another they were quickly into fisticuffs (or beak-and-wing-cuffs), scuffle-splashing, clucking insult or challenge, until the rival to the established male would take to the wing either for a break or to get next to the female. In the latter case, the male would take to the air also, in pursuit.
The female? She swam demurely apart waiting for the victor.
There was clearly one established male who for the moment was the dominant one but the rival kept coming back while I was watching and they were still at it when I left. The established one has the psychological dominance factor on his side, which is a strong advantage but it is by no means a guarantee of success. The rival might wear him down. Or the established one might become injured. Being a male and keeping one’s bird is not easy.
According to Charles Darwin, genders of many species but many birds in particular have become colour-differentiated through part of the evolutionary process described as sexual selection (The Descent of Man and Selection in Relation to Sex, 1871). This has reached amazing and one might say even bizarre though beautiful extremes with such birds as the peacock and the bird of paradise.
Darwin’s ideas make more sense than other explanations being proposed but it is nevertheless hard to credit that a female’s appreciation of colour, shape and behaviour would so impress upon the male the need to flaunt gaudy colour and shape in direct contravention of the need to survive predators by NOT calling such attention to himself. Still, there is no other viable contender explanation around (as distinct from the Mandarin contender, who may still be biding his time or pressing his suit, which if the established male has anything to say about it, is all he is going to press).
Aix galericulata is the Latin species name and the only other species in the Aix genus is the North American Wood duck. A chromosome in the Mandarin makes hybridisation between the two impossible.
Mandarin Ducks originate in East Asia but have been kept in Europe in aviaries and in ponds and lakes. Stephens Green used to have some, along with many other kinds of wildfowl, until the OPW allowed the Herring Gulls to take over to the extent that they have. I have not seen them do it but would not be in the least surprised if the gulls ate the chicks of many of the waterfowl species until they died out or took off somewhere else.
However, there have been feral Mandarin populations in Ireland for some time, notably in Co. Down and in Wexford and pairs may be establishing themselves in other places, including in the Glasnevin/ Drumcondra area, based around the Tolka (and perhaps the Royal Canal).
The Mandarin is a perching duck and this kind have feet capable of grasping a branch. They build their nests in hollows in trees which is good for the safety of the nesting female and the eggs. But what of the chicks or ducklings? As we know, ducklings take to the water long before they can fly. So what can these ducklings in tree hollows, many feet from the ground, do? They simply jump. A veritable leap into the unknown.
When they hit the ground, which at first sight seems to ensure they have broken practically every bone in their little bodies or a least concussed themselves and messed up their insides, they bounce a little, get up and waddle to their mother. Yes, she called them out, which is why they came.
One needs to see the process to believe and I have included some Youtube links. It would seem at first that they need soft leaf litter or water in which to land but one of the links I have posted shows Mandarin ducklings jumping from a nestbox on to bare stone — and getting up, apparently unhurt. It is difficult to understand, even with accounting for the relationship of weight to surviving a fall. We probably know that we can drop lots of insect species on to the ground and they don’t get hurt but the principle goes farther — apparently a mouse can survive a fall from a great height (unless a hawk gets it on the way down, or a cat is waiting below); conversely a fall of four foot on to its feet can kill an elephant (so it is said — I have not actually tried this with elephants but I have inadvertently confirmed the mouse theory).
Often invasive species should not be welcomed as they upset the natural ecological balance. The grey squirrel in the nearby Botanic Gardens, originally from the USA, may be cute but it is helping to wipe out the native red species. And that’s just one of the invasive species of animal and plant that are causing problems in Ireland (see https://rebelbreeze.wordpress.com/2014/07/01/the-scent-of-intruders/). On the other hand, the widely-distributed Red Valerian (also with white and pink varieties) does not seem to be causing any problems and it is difficult to see how the Mandarin can become a serious problem either. But of course, one does not know for sure. It can be stated that the populations so far established in Britain and in Ireland do not seem to have caused any ecological problems. And it is true that we don’t have many dense woods in Ireland anywhere (thanks to certain human invaders in our history), least of all close to slow-flowing water, although some species have shown remarkable adaptability, witness in these climes the rat, fox, pigeon, herring gull and, of course, homo sapiens.
One of the curious things about the Mandarin is the name we have for it. Apparently, it is a Portuguese word for the Chinese government bureaucrats in existence when the Portuguese first began to trade with them (before they and other Europeans decided to invade China and confiscate areas, in particular ports and islands). How they became associated with the duck was not revealed in my short internet search.
However, in China and in Korea the mandarin duck is associated with fertility, good fortune and constancy in monogamy, so that it is often presented as a wedding gift, either as living pairs or symbolically in an ornament. It is not currently considered an extermination-threatened species.
Video links (second one is of merganser ducklings and is even more impressive):