Description
The Kanderdelta is an artificial delta created in the 18th century. Before its construction, the Kander River bypassed Lake Thun entirely. The river deposits substantial amounts of gravel into the delta and the lake, necessitating regular gravel extraction. At the same time, these gravel banks have become one of the few remaining breeding sites for the Kulik Sljepčić in Switzerland.
The delta features a dynamic mix of floodplain forests, still and flowing waters, gravel banks, and steep riverbanks, forming a unique and valuable natural habitat - a rarity in Switzerland. This exceptional ecosystem lies close to the city of Thun, resulting in conflicts between recreational use and conservation efforts. While the lakeshore is accessible year-round, there are even dedicated barbequing areas at the outer edge of the delta. A ranger frequently patrols the area, offering useful information to visitors.
Although the Kulik Sljepčić is the region's flagship species, over 200 bird species have been recorded here. The steep banks provide nesting sites for Vodomar and Vodenkos. In the floodplain forests, breeding birds like Mali djetao, Kukavica, and possibly Sokol Lastavičar, which can be observed from April to September, find their habitats. Vuga and Slavuj are relatively common, possibly you might see a Gak or Mala Bijela Čaplja. Žuta Čaplja has also been observed.
Waders and waterbirds use the delta as a stopover during spring and autumn migrations. The Krivokljuna Prutka is among the most frequent visitors. Other common sightings during migration seasons include Prutka Migavica, Crnokrila Prutka, Kulik Blatarić, and Mali Žalar. Less common species like Kameničak and Sijedi Žalar make appearances. During these times, the reeds are utilized by Sjenica Mošnjarka and Eja Močvarica.
In spring, the delta additionally hosts Crvenonoga Prutka and Pršljivac, as well as Prugasti Pozviždač and Crnoglavi Galeb. Inland, Šumska Crvenperka finds refuge in the floodplain forest. Later in spring and into summer, the Šumski Zviždak appears here, and over the lake, migrating Crna Čigra can be spotted. Exceptional sightings include its relatives, the Bjelokrila Čigra, Bjelobrada Čigra, Mala Čigra, Debelokljuna Čigra, and Dugokljuna Čigra.
In late summer, the rare Bijeli Žalar is occasionally reported, while from September through May, Utva can be seen resting on the lake. Autumn brings irregular sightings of Zlatar Pijukavac, followed later by the more frequent Žalar Cirikavac. From winter to spring, Patka Žličarka and Zviždara rest on the lake, but rarer birds are also possible, as one sighting of Patka ledara proves.
The Kanderdelta is also a hotspot for rare waders. Eight confirmed sightings of Oštrigar have been recorded in April and June. Other notable species include Rđasti Žalar, Modronoga Sabljarka, Morski Kulik, and Ćukavica. Additional rarities such as Primorska Trepetljka, Sjeverni plijenor, Žuti Voljić, Troprsti Zlatar, Kratkoprsta ševa, Tankokljuna liskonoga, Ušati gnjurac, Daurska Lastavica, Kratkorepi pomornik, Veliki pomornik, Lastorepi galeb, and Mala Šljuka have also been observed.
Details
Access
The Kanderdelta is easily accessible by bus from Thun (stop: Einigen, Kanderbrück). A parking lot is also available a few hundred meters away (Press P on the map). The area can only be explored on foot via a narrow path. This trail is not marked on maps and leads along the strictly protected Kander (1), where the Kulik Sljepčić nests on the gravel banks, through floodplain forests, and past a still water body created by gravel extraction (Unteres Kandergrien), which is often visited by herons (2), to the delta (3).
Depending on the water level, the 30 to 40-meter-wide shoreline strip of the delta can be walked on. However, it’s obviously preferable not to disturb or approach any wading birds that might be present. On the other side of the Kandergrien, there is a meadow for lounging (4) with a good view of the lake, and a kiosk operates there during the warmer months.
