The seal was spotted last week in the Merwede Canal in Utrecht and yesterday in the Amstel River near Amsterdam, where it was resting on a pier at Park Somerlust. After detailed investigation, the centre concluded that it was the same seal.
Recognisable by its spotted pattern
‘The spot pattern of a seal is as unique as a fingerprint in humans,’ explains researcher Beatriz Rapado-Tamarit of the WEC/Seal Centre Pieterburen. The researchers at the Seal Centre have years of experience with photo identification of seals, especially in the context of scientific research into mother-pup behaviour in the Dollard.
They use both software and their own analysis for this purpose. This method is completely non-invasive and avoids the need to capture or tag animals, which is important because capture causes a great deal of stress and can alter the seal's behaviour.
Three points of identification required
In this case, it was not possible to use software because the quality of the photographs was not high enough. Therefore, the experts relied entirely on their trained eyes.
“We made two identification cards and carefully placed the photos side by side,” Beatriz explains further. ‘On the left flank, we saw matching white spots, the same markings on the forehead, and two distinctive dark spots on the right side of the neck. According to our protocol, we need at least three clear characteristics on three different parts of the body to confirm that it is the same seal. In this case, everything matched.’
The interactive exhibition at the WEC includes a section devoted to photo identification, where visitors can try to identify and match seal spot patterns themselves.
Urgent call to the public
The Seal Centre urges the public to treat the seal with respect and to keep a sufficient distance (at least 30 metres). For the time being, the animal is in good health and – as long as it is not disturbed – no rescue is necessary. ‘Let's all work together to prevent this,’ emphasises Emmy Venema, stranding coordinator at the WEC/Seal Centre.
The centre is particularly concerned about the crowds now that the good weather is likely to attract many visitors to the park. For this reason, the area around the seal has been temporarily cordoned off with tape and the Seal Centre is in contact with the Amsterdam police. Last night, there was already a report of drunk visitors disturbing the animal.
Seal centre is the only organisation authorised to intervene
The Seal Centre Pieterburen is the only organisation in the Netherlands licensed to take in seals from inland areas. If you have any doubts about the welfare of a seal or if there appears to be an emergency, the Seal Centre urges you to contact them immediately on 0595 526 526.
Special but not unique
It is unusual, but not unique, for a seal to swim so far inland. Seals are well able to adapt to fresh water and feed on freshwater fish without difficulty. They used to be more common in Dutch inland waters, but nowadays waterworks make these journeys more difficult. This makes an encounter such as the one in the Amstel River today quite special. Nevertheless, the Seal Centre receives at least one report of a seal in fresh water every month.
Foto Utrecht (land): Toon Vernooij
Foto Amsterdam (steiger): Thom Pol
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