In the Netherlands there is a stable population of harbour (Phoca vitulina) and grey (Halichoerus grypus) seals. Nowadays, both species have recovered from being hunted to near or complete extermination, but they are still considered vulnerable and therefore they are being rehabilitated when found stranded along the Dutch coast. Reason for stranding can vary, but the more strenuous cases are those that involve contact with human waste, often discarded fishing gear. In this study we describe the rescue protocol used by the Sealcentre Pieterburen regarding seals affected by human debris and we focus on two case reports explaining the use of endoscopy as a life-saving treatment on two animals.
From 2007 to 2017, a total of 42 animals were reported to the Sealcentre Pieterburen with fishing net, fishing lines, or other debris harming their body. From these, six animals were found dead in different decomposition stages; four animals could not be caught, neither be released from the net; 24 individuals were released on site, after confirming that the net did not cause any or severe wound; and eight animals were brought into rehabilitation.
We present two case reports, both harbour seals, brought to rehabilitation in 2017. The first case was an animal that presented two fishing hooks at different levels of the digestive tract. The second case was an animal with a metal fishing artefact in the stomach that perforated the stomach and abdominal wall. The animals were anaesthetized to perform an upper endoscopy in order to remove the artefacts. The procedure was successful and after a rehabilitation period of 48 and 57 days, respectively, both animals were released. These cases show severe interactions with human artefacts and that treatment is possible, yet exhaustive.
We thank the staff and volunteers of the Sealcentre Pieterburen as well as the volunteers of the EHBZ stranding network for their help during the procedures.