HELCOM Workshop - Seal – fish/fisheries interaction in the Baltic Sea Copenhagen, 27.06.2019 Status of Grey Seals in German Baltic waters with implications for management Michael Dähne
Protection of Grey Seals in International Agreements Distribution wikipedia • Subspecies in the Baltic Sea (Halichoerus grypus grypus) • Habitats Directive – Annex II: core areas of their habitat are designated as sites of Community importance (SCIs) and included in the Natura 2000 network. These sites must be managed in accordance with the ecological needs of the species. – Annex V: Species that declined and are endangered due to takes and therefore have to be protected from further uncontrolled taking. Member States must ensure that their exploitation and taking in the wild is compatible with maintaining them in a favourable conservation status. • Species was extinct in Germany from 1920-2005 • German species protection act : Specially protected species, unfavourable status according to habitats directive 2
Development on permanently occupied sites Greifswalder Oie Großer Stubber March February Relative Number Relative Number Month Month Relative Number Relative Number Average: 5-20 animals Still growing No growth Year Year 3
Number of grey seals 100 150 200 50 0 J-17 Seasonal occurence in German Waters F-17 M-17 Herring spawning A-17 M-17 J-17 Moult J-17 A-17 S-17 Oie O-17 N-17 Stubber D-17 J-18 F-18 Herring spawning M-18 Ice A-18 M-18 Moult J-18
Development in strandings of grey seals Mean number of strandings 2012-16 5
Strandings event 2017 23 male grey seals stranded 10.09. und 04.12.17 in a confined area of ~5 km All in good condition No injuries Well fed Michael Kühl / BfN Simultanous counts: Median of 29 animals in the area ~24 – 47 % of local animals died
Strandings event 2017 Only animals 10.09.-04.12 . • Size selection (> 2m) • Lung edemas / Gas in lymph nodes Body length [cm] 250 • No other cause of death (bacteria / virus / toxikology) 200 • Large fish traps were deployed close to the stranding site 150 • No bycatch reported • Suspicion: tacit acceptance of unreported taking of a specially 100 protected species • Investigations on legal charge was 2012-2016 2017 carried out Prosecution deemed charge as justified Could not charge the suspect Swimming fish trap
Bycatch May 2018 Greifswalder Oie What can we do about these issues? Hagen Phoenix, Archaeomare e.V.
Goal: seal safe fishing gear Seal Exclusion Devices (SEDs) 9 Königson et al. 2015
Define measures Large dots = females grey seal 160 140 circumference (axle) 120 100 80 60 a j s na 100 150 200 250 Total Length 10
Define measures Size of dots = Month Measures were agreed upon grey seal 160 on invitation by 140 Agency for Agriculture, food safety and fisheries M/V circumference (axle) 120 by fishermen, fisheries control, and scientists 100 taking fisheries concerns into account 80 75 cm circumference 60 a j s na 100 150 200 250 Total Length 11
Exclusion Device (defined as obligatory in auxillary condition for trap net licenses) • Valid for large fish traps with no opening to the surface • Only for the area of concern • Definition of exclusion device • Largest possible circumference = 75 cm • Material: • Non-stretchable rope (polypropylen 10 mm) or • steel of more than 4 mm diameter • Exclusion device must be fixed to net in first compartment • No definition for geometric shape • Slit entrances have to be treated differently • All marine mammal bycatch has to be reported and live animals have to be released • If animals are caught frequently, it has to be reported and measures have to be taken to prevent any further bycatch . The fyke may have to be removed. 12
Thank you for your attention Linda Westphal DMM 13
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