The Eurasian dotterel is a bird which doesn’t seem so far removed from its close relatives upon first glance, yet a sortie into its ecology soon proves this to be untrue. Its appearance, particularly in the winter months, resembles a golden plover, although the dotterel is classified in the same genus as the ringed plovers. However, unlike the ringed plovers – and practically every other European plover – dotterel are very rarely found near water. Dotterel will breed in the summer months at the very top of mountains and plateaux, which in the UK means upland Scotland and a select few sites in northern England. So how did I manage to photograph the bird below at Ditchling Beacon, in south coast Sussex?
Apart from its unusual habitat choices, another interesting aspect of this species’ behaviour is its migration habits. In spring, and occasionally in autumn, this species will migrate in parties known as ‘trips’, which can number about 20-30 individuals nowadays. In both seasons another peculiar feature of their migration is that they regularly stop over at traditional sites, which many decades ago would draw hunters from far and wide. These traditional sites seem to be clustered further north but there are a handful in southern counties, with Ditchling Beacon occasionally hosting the bird. The ‘trips’ won’t always stay true to their traditional sites, with the first group of dotterel to be recorded in Surrey for 128 years appearing near Banstead in 2012.
The word ‘dotterel’ was used in the 1400s for someone simple-minded or a dotard as well as for the bird, and it is unsure which word stemmed from which. The dotterel is so-called due to the ease with which one can approach them, making them easy targets for hunters in addition to their predictable movements. As you can see from the photo above, I was not willing to approach the Ditchling birds too closely in case they were disturbed. Birds on migration have enough trials to overcome without the added pressures of humans and dogs disturbing birds when they could be feeding and putting on weight for the next leg of their journey.
Third in the list of unusual details of dotterel ecology is their plumage. The three Ditchling birds were all either juveniles or winter-plumaged, so more dull than one would expect to see them on their breeding grounds. However, as the ID composite above shows, dotterel are very attractive birds in the summer months. As you might anticipate, the two birds in the foreground are adults in breeding plumage, although the sex of each might surprise you. The duller bird on the left is the male, while the more strikingly-plumaged individual on the right is the female.
The dotterel is one of the very few bird species in which the roles of either sex could be considered reversed, with the male incubating the eggs and taking care of the chicks, and therefore requiring more camouflaged feathering. The females on the other hand are polyandrous, producing several clutches with different males each season. This is rare in birds, with only a tiny fraction of species exhibiting this behaviour, mostly shorebirds such as phalaropes and jacanas. Polygyny, the male equivalent, is much more frequent, occurring in 8% of bird species, such as birds-of-paradise and grouse, in comparison to the 0.4% of bird species which are polyandrous. Polygynandry is the rarest mating system, where both the males and females are promiscuous. There may be several reasons why these behaviours are practised, but in polyandrous species the clutch success rate is often lower. As a result, it is more beneficial for the female to have her progeny guarded by multiple males in the hope that at least one of them is a competent father.
As you can see, the dotterel is a fascinating bird, much more so than one would have assumed from my photo above. I hope that trips of dotterel will long be stopping off at their regular haunts for many migration cycles to come, and I hope that soon I’ll have the chance to see their unusual breeding behaviour first hand.