Common Grackle migrating over Kamperhoek in the Netherlands in April 2013 

In April 2013, I was involved in a study on the feeding behaviour of birds in onion fields in Flevoland, the Netherlands. The first five days of the month were remarkably cold for the time of year. Apart from a relatively warm period in the beginning of March, when thousands of Common Cranes Grus grus migrated northward, the winter seemed endless. Therefore, it came as no surprise that I encountered only very few birds. During the first weekend of April, however, things finally started to change. On Saturday, I enjoyed gripping views of a female Eurasian Eagle-Owl Bubo bubo with two chicks in a quarry near Winterswijk, Gelderland, as well as of displaying Black Woodpeckers Dryocopus martius and Middle Spotted Woodpeckers Dendrocopos medius and a Eurasian Treecreeper Certhia familiaris in nearby forests. Sunday started foggy but eventually turned into a beautiful day. Although a walk through the Kennemerduinen near Bloemendaal, Noord-Holland, produced low numbers of migrants, it felt like something big was about to happen.
The next morning, Monday 8 April, as I was on my way to Flevoland, I decided to visit the famous migration hot spot Kamperhoek near Swifterbant in that same province. Since this was my first visit I did not really know what to expect. While driving on the A6 near Lelystad, Flevoland, I saw hundreds of Common Starlings Sturnus vulgaris, heading in the same direction as I was. Nervously, I speeded up a little. Around 08:15 I parked my car on the Ketelmeerdijk. As I got out of the car I was greeted by an unpleasantly cold wind from the east and immediately it felt like winter again. This explained why the four birdwatchers that were already present were sheltering behind their vehicles. I briefly said hi and sat down next to Ton Lakeman.
Next to him sat Mervyn Roos, Thijs Knol and Guido Berger, all regular visitors of Kamperhoek.
It did not take long to realise that many birds were on the move. In the next 45 minutes we counted for example around 300 White-fronted Geese Anser albifrons, 500 Common Wood Pigeons Columba palumbus, a Western Great Egret Casmerodius albus albus, two Western Marsh Harriers Circus aeruginosus, 1500 Common Starlings, 100 Meadow Pipits Anthus pratensis and 80 Common Chaffinches Fringilla coelebs. A Barn Swallow Hirundo rustica was still a year tick for me.

Common Wood Pigeons Columba palumba, Kamperhoek, Flevoland, the Netherlands, 10:33 8 April 2013 (Roy Slaterus).

The combination of cold wind and numerous birds meant that not much talking was done. We were all just focused on one thing: counting. I was very much impressed by the hundreds of Common Wood Pigeons that were flying overhead against the wind across the Ketelmeer. By the end of the day their numbers would pass 12 000 - a record for this location. I was also impressed by Mervyn's superb eyesight. He repeatedly found and identified birds that were still miles away. One of the species he picked up easily was Mistle Thrush Turdus viscivorus. Most of the 27 individuals that we saw between 09:00 and 10:45 followed the same route crossing the Ketelmeerdijk c 500 m south-east of where we sat. In strong light and at long range, obviously, there was not much detail to rely on.
Because I was intrigued by this 'channel' of Mistle Thrushes I regularly scanned the area. At 10:49 I noticed a strange bird taking the same route. It seemed slightly bigger than a Mistle Thrush, for a moment making me wonder if it could be a White's Thrush Zoothera aurea. I said something like: "What kind of large thrush is that?" Immediately, I grabbed my camera and took three photos. Ton also saw the bird, but the others were still counting starlings and pigeons. It all went fast and as the bird disappeared over the lake, I presumed its identity would always remain a mystery. The images on the display of my camera showed a dark bird with a funny tail and a strong bill. At that point, however, Mervyn got his eyes on the bird and shouted out loud. Miraculously, it had returned to the dike and was now coming closer. Seconds later it flew straight over our heads. In much better light I had a good look at it. It now reminded me of a Common Grackle Quiscalus quiscula, a species I had seen some years ago in the United States. I heard Mervyn fire a few shots with his camera; the best sound I could imagine at this moment! The others were also looking up and watching this extraordinary bird. Adrenaline was pumping. Again, it changed its path and flew to the north-east. Gradually it became a small dot up in the sky, just like so many other migrants.

Common Grackle Quiscalus quiscula Kamperhoek Netherlands Europe 8 April 2013 Flight
Common Grackle Quiscalus quiscula, Kamperhoek, Flevoland, the Netherlands, 10:50 8 April 2013 (Roy Slaterus). Just seconds after I had found it and still at a distance of c 450 m! 
Common Grackle Quiscalus quiscula Kamperhoek Netherlands Europe 8 April 2013 Flight
Common Grackle Quiscalus quiscula, Kamperhoek, Flevoland, the Netherlands, 10:53 8 April 2013 (Mervyn Roos).
Contrast between blue head and brown body typical of Q q versicolor.
Common Grackle Quiscalus quiscula Kamperhoek Netherlands Europe 8 April 2013 Flight
Common Grackle Quiscalus quiscula, Kamperhoek, Flevoland, the Netherlands, 10:53 8 April 2013 (Mervyn Roos).
Contrast between blue head and brown body typical of Q q versicolor.

Common Grackles Quiscalus quiscula from The Crossley ID Guide: Eastern Birds (website).

The bird left us confused. Although I suspected that it could have been a Common Grackle, I was far from sure about this identification. A few other species from other continents were also mentioned. What we did know was that this was no European species. Our hope was that the photos would allow identification at a later point. We were just not prepared for a Common Grackle yet!
It was a weird sensation, having just picked out this amazing bird from a stream of common migrants and then trying to remember what it looked like. Every detail could be relevant. At the same time Common Wood Pigeons and Common Starlings were flying by in even higher numbers than before. They literally forced us to start counting again. Also a Black Stork Ciconia nigra and a Red Kite Milvus milvus drew our attention. Around noon things slowed down a bit and I decided to leave. I just needed to go home and check every field guide in my bookcase for this one bird...

Common Wood Pigeons Columba palumba, Kamperhoek, Flevoland, the Netherlands, 10:59 8 April 2013 (Roy Slaterus).

Common Starlings Sturnus vulgaris and Common Wood Pigeons Columba palumba, Kamperhoek, Flevoland, the Netherlands, 11:38 8 April 2013 (Roy Slaterus).

Red Kite Milvus milvus, Kamperhoek, Flevoland, the Netherlands, 12:06 8 April 2013 (Roy Slaterus).

After studying the photos it became clear that the Kamperhoek bird indeed was a Common Grackle - a North American species that had never been seen before in the Netherlands. Size and proportions, pale eye, strong bill and wedge-shaped tail all pointed at Common Grackle, while the strong contrast between glossy blue head and neck and glossy brown body was typical of the migratory subspecies Q q versicolor (Bronzed Grackle). Age and sex could not be determined with certainty; females are slightly smaller than males and show less gloss. Based on the large amount of gloss in the plumage and the triangular appearance of the tail in side view it was probably a male.

First for the Netherlands and Western Palearctic
Although the occurrence of Common Grackle in Europe was already predicted - e.g. in an article about potential North American vagrants by Chandler Robbins (Br Birds 73: 448-457, 1980) - the Kamperhoek bird came as a surprise to all Dutch birders. There were no previous records of Common Grackle in the Netherlands. Within the Western Palearctic only one other sighting is known, namely at Gevninge, Sjælland, Denmark, from late-March to c 20 April 1970. This sighting was, however, not accepted by the Danish rarities committee. The reason for this is not entirely clear; from what can be traced after so many years it seems that this bird showed no signs of captivity.   

Common Grackle is a common to abundant species in a large part of North America. It is also one of the most abundant species when watching visual migration in eastern North America. Along the East Coast it migrates north between mid-February and mid-April. Bronzed Grackle is a migrant that breeds in Canada (e.g. on Newfoundland) and in a large part of the United States and winters as south as Texas. Northern birds tend to migrate the furthest ('leap-frog migration'). 
Common Grackle is regularly found outside its normal range, for example along the West Coast of the United States and north of its breeding range in Canada. Interesting records are those of Bronzed Grackles collected near Wainwright, Alaska, on 17 June 1943 and near Barrow, Alaska, from 24-27 June 2012. Both locations are situated along the Arctic Ocean, at c 2000 km north-west of the closest breeding areas. There are also several records known from Bermuda, in the Atlantic Ocean c 1000 km off North Carolina. In March-April 2003 an influx took place, with for example 12 individuals on 11 March and 20 on 19 March, illustrating the potential for transatlantic vagrancy. 

Common Grackle Quiscalus quiscula, Barrow, Alaska, United States, 24 June 2012 (Gavin Bieber) - a major rarity at the northernmost point of the United States! Contrast between blue head and brown body typical of Q q versicolor

Other North American landbirds that have been recorded in the Netherlands are Belted Kingfisher Megaceryle alcyon, Red-eyed Vireo Vireo olivaceus (nine records), Northern Mockingbird Mimus polyglottos, Grey-cheeked Thrush Catharus minimus, American Robin Turdus migratorius, Indigo Bunting Passerina cyanea (two), Song Sparrow Melospiza melodiaWhite-throated Sparrow Zonotrichia albicollis (five), Dark-eyed Junco Junco hyemalis (three), Yellow-headed Blackbird Xanthocephalus xanthocephalus, Baltimore Oriole Icterus galbula (two), Northern Waterthrush Parkesia noveboracensis and Myrtle Warbler Setophaga coronata. Most recent were Song Sparrow (April 2006), Baltimore Oriole (December 2009 to April 2010), Northern Waterthrush (September 2010), American Robin (April 2014), Dark-eyed Junco (February to April 2015 and May 2017), Red-eyed Vireo (October 2018) and Grey-cheeked Thrush (November 2018).