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Flora & Fauna (media)
Common Noctule (Nyctalus noctula)    (Mammals)    24701
Brunflagermus (dk)   Nóctulo Común (es)  
Common Noctule 357    (6 photos)
2019-10-21   Kalvebod Fælled, Amager, Denmark

Two individuals foraging above Kalvebodstien during daytime. The species is known for this.

Very similar species Serotine Bat (Eptesicus serotinus) is also present in Denmark but apparently more of a nocturnal flyer, which might be the reason why all observations of large daytime flying bats are referred to as Common Noctules. At least there are only observations of the latter in the webbase at www.fugleognatur.dk.

However, to separate them reliably, visually, you have to see the shape of the tragus, part of the outer ear, which is not possible with these photos. But longer and narrower wings is also mentioned as a visual difference to focus on. A relative feature for sure, but comparing with photos online, it does look like there is a good resemblance to my bat.

Another id marker is the flight height, where the Noctule averagely forages between 50-100 meters above the ground, and the Serotine Bat is supposed to forage below 50 meters. Overlap and an insecure feature to rely on, but overall these two animals were often much higher up than when I took these photos, supporting that they were indeed noctules.
Common Noctule 587    (3 photos)
2022-04-13   Kongelunden, Amager, Denmark

Was flying around along Fasanstien at broad daylight. Probably flushed from its hide. It looked small, but iNaturalist gives a single suggestion, that it is this species. And comparing with an individual, 357, that I had on Kalvebod Fælled, in the open, the shape and general profile look very similar, why I, with my limited knowledge of the subject, decide to trust iNa.
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