Status of Grey Seals in German Baltic waters with implications for - - PowerPoint PPT Presentation

Status of Grey Seals in German Baltic waters with implications for management

Michael Dähne

HELCOM Workshop - Seal – fish/fisheries interaction in the Baltic Sea

Copenhagen, 27.06.2019

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Protection of Grey Seals in International Agreements

• 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

Distribution

wikipedia

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Development on permanently occupied sites

Großer Stubber Greifswalder Oie Relative Number Relative Number Relative Number Relative Number Month Month Year Year February March

Average: 5-20 animals No growth Still growing

50 100 150 200

J-17 F-17 M-17 A-17 M-17 J-17 J-17 A-17 S-17 O-17 N-17 D-17 J-18 F-18 M-18 A-18 M-18 J-18 Number of grey seals

Oie Stubber

Herring spawning Herring spawning Moult Moult

Seasonal occurence in German Waters

Ice

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Mean number of strandings 2012-16

Development in strandings of grey seals

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 Simultanous counts: Median of 29 animals in the area ~24 – 47 % of local animals died

Michael Kühl / BfN

Strandings event 2017

Body length [cm] 2012-2016 2017

Only animals 10.09.-04.12. 250 200 150 100

• Size selection (> 2m)
• Lung edemas / Gas in lymph nodes
• No other cause of death (bacteria /

virus / toxikology)

• Large fish traps were deployed close to

the stranding site

• No bycatch reported
• Suspicion: tacit acceptance of

unreported taking of a specially protected species

• Investigations on legal charge was

carried out  Prosecution deemed charge as justified  Could not charge the suspect

Swimming fish trap

Bycatch May 2018 Greifswalder Oie

Hagen Phoenix, Archaeomare e.V.

What can we do about these issues?

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Goal: seal safe fishing gear

Seal Exclusion Devices (SEDs)

Königson et al. 2015

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Define measures

100 150 200 250 60 80 100 120 140 160

Large dots = females

Total Length circumference (axle) grey seal a j s na

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100 150 200 250 60 80 100 120 140 160

Size of dots = Month

Total Length circumference (axle) grey seal a j s na

Define measures

Measures were agreed upon

• n invitation by

Agency for Agriculture, food safety and fisheries M/V by fishermen, fisheries control, and scientists taking fisheries concerns into account

75 cm circumference

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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.

13 Linda Westphal DMM

Thank you for your attention