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Illustrations: see on
https://lutzluecker.blog4ever.com/nouvelles-notes-de-terrain-sur-la-reproduction-du-pluvier-guignard-charadrius-morinellus-en-norvege-arctique
After finding my first Dotterel nest in the year 2000 I met Bärbel and Siegfried (deceased in 2005) from Greifswald/Germany in 2002. They had already realised that in the high Finnmark Arctic female Dotterels participate more often than commonly believed in incubation, sometimes until the chicks hatch. Until 2011 we observed 24 nests long enough to see that in 18 cases (75%) females spent at least several days incubating with the males after completing their clutch. On Hardangervidda, J.A. Kalas, I. Byrkjedal et al. observed only 9 out of 27 females (33%) doing so in the 1980s. Various observers south of the Polar Circle have noticed that a large number of females just disappear after egg-laying. We think that they move further and further north, copulating with several males until they reach the shores of the Barents Sea and lay their last clutch in late June or even early July. (Female Dotterels can lay 5 clutches, perhaps more, in one season.) In one case we even observed a female alone with her chicks for 5 days in a small area, as well as one that successfully prevented « her » male from taking over the chicks on the day they hatched. However, she had disappeared on the next morning. - We have observed females with chicks at least 5 or 6 times, mostly during hatching, but also on the next day (still trying to keep the male at bay), and probably even with fledged young birds albeit we have no sure-fire proof that those birds were „family“.
By the way we never tried to catch and band or tag « our » Dotterels and mostly watched them through a telescope from a safe distance. Photography was generally used just to get portraits of each pair ; so we have a gallery of males and females that were « sexed » correctly (which is sometimes difficult when you cannot see the partner ; females in worn plumage in July may resemble males, and males are sometimes more colourful in May/June than certain females in July/August). The main features of a male are the brownish crown with lots of little beige streaks, even on the rear half, and the « unshaven chin ». Females have a blackish rear crown and a very white face, as well as a larger black belly-patch with no whitish dots.
As our large study areas are crossed by a main carriageway ( riksveien) and several motorable gravel roads, more and more birders, twitchers, photographers and even egg-collectors have invaded the place, frequently following us when walking around with a tripod, in order to find Dotterels, Ptarmigan, Shorelarks and Purple Sandpipers. Another drawback to those fjell species are the numerous skuas there. Lemmings have been very scarce in most years, especially above 300m a.s.l. and so the skuas heavily rely on waders’ eggs and chicks. This is why we have considerably reduced our activities since 2011 and try to walk off-road across the tundra as little as possible, rarely spending more than a few minutes near a nest, to avoid attracting skuas or other humans.
22 out of the last 48 nests we found were less than 50 m from man-made structures (roads, tracks, ditches, reindeer fences, even a fisherman’s summer hut.) We found several nests less than 25m from the riksveien ! Which means that anyone wishing to find these birds can well renounce trampling over acres of barren tundra during the breeding season and risk squashing tiny chicks or eggs. Every year we see groups of foreign „birders“ staging genuine „beats“ across this type of terrain in order to photograph or twitch Dotterel and Ptarmigan, this part of the Varangerhalvöya being probably the only place in Finnmark where you might find them every year without having to walk uphill for miles. –
Why do Dotterels often stick to man-made structures? After late winters the first „islands“ of vegetation that emerge from the snow in May are immediately colonised by bigger birds: skuas, ptarmigan and golden plover. Except in areas close to a road.- Perhaps roadsides are also attractive because there are generally fewer predators there. This is certain as far as fences are concerned. A chick that hides near or under a fence cannot be caught by skuas ; they would run the risk of breaking their wings against the wires. And the hundreds of old fence poles lying on the ground offer shelter from rain, wind … and predators, too. But there is one danger: once we found a Dotterel nest that was 2 or 3 m from a fence and had been trampled by reindeer which often follow the barriers when migrating over long distances. – When we were searching for nests from our car, some females would approach, stand on the road and even « shout » at us until we drove away. A strategy to be avoided where 40-ton trucks may appear any moment.
The breeding season may start in late May when the snow melts early. But in some years we notice clutches laid as late as 7th July, especially when the lakes at 300/350m a.s.l. do not thaw before that date (2008 and 2014). So you might see mating pairs in late June (not necessarily to produce a replacement but a first clutch) as well as newborn chicks in the highest parts of our area at the same time. From the first egg to the last fledged chick a season may last between 80 and 90 days. Some very late clutches were abandoned after a few days.-
A few far-away ring recoveries (e.g. between Ireland and the Jenissei basin in Siberia) have suggested that Dotterels are not at all faithful to their birthplace. But it is hard to generalise this tendency which might only be valid for females. In 2004 I found a nest exactly in the same spot as the year before. Of course I marked the place and checked on it every year. And found an incubating bird again in 2011 and 2015. Very surprising: the nest scoop is in a rather unfavourable, very wet area and had almost disappeared twice due to meltwater erosion. But the bird always scraped out a new scoop, perhaps not being able to convince a female to lay her eggs there (and not elsewhere) every year. But there were always one or two nests less than 90m from this spot. It is highly unlikely that there were different „owners“ of that nest scoop, which means that this one must have lived at least 13 years (if born in 2002), which is a „record“ but not at all surprising: New Zealand Dotterels live until they are more than 30, perhaps even 40 years old; the record for the (much smaller) Dunlin is 28.
Birders and/or photographers generally think that Dotterels are not shy and can be approached without being seriously disturbed. This is a big mistake. After finding a new nest we can always see that the incubating bird is heavily stressed (fast heartbeats) even if we stay away as far as 20 or 30m, just watching with telescopes. It will be crouching flat on the ground, trying to get away unnoticed. Some birds will run away and not return to their clutch until you are at least 300m away, never staying on the eggs whenever you come back, until they hatch. We have no clue if the percentage of those „shy“ birds is 15 or rather 50%. All we know is that the number of families in late July and August in a given area can be surprisingly high, which shows that lots of nests have been overlooked. There may be several families where you have walked exactly the same path for 4 or 5 weeks without ever noticing any adults. We think that above 300 m a.s.l. Dotterels are the most abundant wader species on Varanger fjells, more abundant than the much more visible and audible Ringed Tundra and Golden Plovers ; their real numbers have just always been underestimated.
The birds that have seen you walk by a number of times without disturbing them, perhaps spending a few moments sitting on a rock (if possible not permanently looking at them) will sooner or later get accustomed to your presence, sometimes even approaching you in order to check you out. Several times we had the satisfaction that a Dotterel left us alone with its eggs or chicks for a few minutes to have a lunch break or evacuate a tell-tale eggshell. In the early days we sometimes had a small box with meal worms in our pocket and managed to attract a few roaming birds, one of which even came up to us within a few inches…to peep into the box. However, I strongly recommend never to feed incubating birds (or the ones leading chicks). Their concentration might be impaired and approaching predators noticed too late.
As a rule, our long experience has shown that there is no reason to adopt, when watching these attractive birds, a behaviour different from the one demanded in Scotland where Dotterels are a strictly protected « schedule one » species. Willfully disturbing vulnerable birds close to their nest or helpless offspring is an offence in most countries, even in absence of signs which say so. In our view, researchers must also abide by this rule until they can be 100% sure that the birds do not mind their presence any more and that their presence near a nest is not likely to attract predators. This needs many days in the process of „getting to know each other“ and will often not work at all. - A century ago the famous Bengt Berg proved that with a lot of patience we might even make a Dotterel incubate its clutch in our hands. An enticing thought. But it is absolutely useless to repeat this experience although quite a few photographers have tried.
I made a video showing that satisfying observations of Dotterels and many other northern species can be made even if people stay less than 50m from roads and tracks. (Do NOT click on the link. Copy its URL and paste it into your browser!)
https://youtu.be/twYaeGwVJWM
To conclude, let me just thank a few friends who have helped us in our field work for several weeks : Christiane & Ernest Duscher, Jean-Marc Lustrat.
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