Wadden Sea, Germany, June, 2023.
The Bird
Members of the Tern family have really similar features in look, sound and migration behaviour, but the Arctic Tern is the one which holds the pole position for the longest migration journey, flying each year from pole to pole. It can be distinguished from other Terns by its graceful and elegant flying style, it looks like it’s swimming through the air with gentle wing beats. If looked up close the Arctic Tern has a short fully red beak, whereas the Common Tern has a black tip on the red beak and is slightly longer.
Migration
They tend to migrate offshore although some individuals may migrate overland, wintering on the edge of pack ice in Antarctica during the Southern Hemisphere summer.
The Arctic Tern is well known for its long yearly pole-to-pole migration, travelling from its Arctic breeding grounds to Antarctica where it enjoys the Antarctic summer covering around 25,000 miles, flying as far as 6,000 miles without a stop.
The Sound
The Arctic Tern sounds quite similar to the Common Tern but there are a few elements we can pick up to distinguish one from the other.
When in colonies there is such a cacophony of calls, also because they tend to share the nesting environment with other terns and even gulls.
The Arctic Tern tends to make a ta-ta-taaaaw ta-ta-taaaw sound, reminding us of a car engine starting, that tentative to start which then at some points kicks in.
- Use the Player to listen the Arctic Tern call. -
Instead the Common Tern can be differentiated by two calls, either its single chirps which are much rarer in the Arctic Tern and the long descending call weeeee-oooooh weeee-oooh.
- Use the Player to listen the Common Tern call. -
Habitat
They forage over streams, ponds, lakes, estuaries, and the open ocean. Arctic Terns breed in treeless areas with little to no ground cover, in open boreal forests, and on small islands and barrier beaches along the northern Atlantic Coast.
The eggs tend to be exposed to the elements and predators, with minimal nest material support. In some cases they nest in the same area as Common Terns and Black-headed Gulls, as we have found out at the Eider Dam, German section of the Wadden Sea.
The Arctic Tern is well known for its long yearly pole-to-pole migration, travelling from its Arctic breeding grounds to Antarctica where it enjoys the Antarctic summer covering around 25,000 miles, flying as far as 6,000 miles without a stop.
- Use the Player to listen a full hour of ambient soundscape. -
Our Encounter
We knew about the Arctic Tern as being a long-distance migratory bird, but we’ve never managed to see one; we do love Terns both for their elegant look and their characteristic vocalisation, and this one was on our list to spot and learn more about it.
When at the German part of the Wadden Sea World Heritage, our local contact Klaus Günther told us about this incredible Black-Headed Gull colony to visit near the Eider Dam, situated at the mouth of the river Eider. This dam regulates the level of the river to keep it constant as the tide difference of the sea there is up to 3 meters. We didn’t expect to find a colony of hundreds of birds nesting close, or even on the dam, you can walk so close to the colony you risk being attacked, or even pooped over, by all these birds. The Black-headed Gulls were the majority, but within their colony, there are a few Common Tern nests clearly identifiable, but no sign of our beloved Arctic Tern yet.
The week after we went with Klaus to ring Spoonbills on a small piece of land called Hallig (it’s not an island) only accessible via tractor or walking when low tide, which we’ve made very clear it is not an island. As soon as we arrived we were blessed by views of pairs of Arctic Terns nesting not far from us, we have finally seen them!
Feeling confident by then about their look and sound, we went back to the Eider Dam to get more videos and recordings, and only then we managed to recognise them, Arctic Terns! There were Common Terns indeed, but not far there was a hidden part of the dam with a small colony of Arctic Terns. Initially, we weren’t able to identify them, not having seen them before, but after having seen and heard them ourselves, we managed to distinguish them inside that mess of a colony.
Imagining that some of these birds may spend our winter time in Antarctica is mind-blowing, such a small animal can travel through so many seas, coasts, countries, and cultures, we can’t be fascinated by their journey. We hope to see them on the way South or coming back North while in West Africa.
You can find it together with other migratory birds in our Immersive Experience about the Wadden Sea.
Sources
https://www.allaboutbirds.org/guide/Arctic_Tern/overview
https://www.rspb.org.uk/birds-and-wildlife/wildlife-guides/bird-a-z/arctic-tern/
