1. Introduction to the Circumpolar World The marine environment
Hreiðar Þór Valtýsson, MSc in Fisheries Biology
Assistant Professor, Faculty of Business and Science, University of Akureyri
Director, the Fisheries Sciences Center at the University of Akureyri
Borgir (2nd floor, office 228), Norðurslóð, 600 Akureyri
Tel.: (office)
Office hours: By appointment

2. Introduction
Hreiðar Þór Valtýsson University of Akureyri 2016
Subject: The Arctic marine environment, biological processes and fisheries
Readings:
ACIA 2004: Key Finding No. 4: Animal species´ diversity, ranges, and distribution will change; p Locate on ACIA web page at:
Arctic flora and fauna – status and conservation: Chapter 8 – The Oceans and seas. Locate on CAFF web page at:
Supplementary material if you want to learn more about this topic:
ACIA Scientific report:
Chapter 13 – Fisheries and aquaculture, Central North Atlantic – Iceland and Greenland (section 13.1, p and section 13.3, p ). Locate on ACIA web page at :
Chapter 9 – Marine systems. Locate on ACIA web page at :
More on my website click NOR0173

3. PASSWORD FOR DOCUMENTS = fish
Introduction
Hreiðar Þór Valtýsson University of Akureyri 2016
The Arctic and life in the Arctic
Key findings #4 –
Climate change, Arctic and fisheries
PASSWORD FOR DOCUMENTS = fish

4. What is the Arctic? The Arctic is in many ways unique
Hreiðar Þór Valtýsson University of Akureyri 2016
The Arctic is in many ways unique
The Arctic is a Mediterranean sea plus some tundra and ice !!
Large continental shelves => higher productivity
Gateway between Atlantic and Pacific
High Arctic
Subarctic

5. What is the Arctic? Boundary: Arctic-Subarctic COLD COLD
Hreiðar Þór Valtýsson University of Akureyri 2016
COLD
Boundary: Arctic-Subarctic
COLD

6. What is the Arctic? Polar fronts River inflow
Hreiðar Þór Valtýsson University of Akureyri 2016
Polar fronts
River inflow
Cold and warmer currents meet => very high productivity
High inflow of freshwater from rivers

7. What is the Arctic? Sea ice Seasonal or permanent sea ice
Hreiðar Þór Valtýsson University of Akureyri 2016
Sea ice
Seasonal or permanent sea ice
Some mammals depend very much on it such as polar bears and some seal species
It scours the bottom in shallow areas => destroys bottom life
However algae thrive on the underside of it in spring, driving the production in the ecosystem

8. What is the Arctic? Light
Hreiðar Þór Valtýsson University of Akureyri 2016
Light
A very high seasonality in sunlight => highly seasonal primary production
Little overall sunlight
We are here

9. Species
Hreiðar Þór Valtýsson University of Akureyri 2016
The ecosystem is simple (i.e. species diversity is low) compared to warmer waters
But: individual species can however reach extremely high abundance

10. Species
Hreiðar Þór Valtýsson University of Akureyri 2016
Organisms are also divided into several groups by where and how they live, the most simple division is:
Plankton (svif ) – Limited ability to move, dependent on currents
Phytoplankton (Plöntusvif) – Microscopic, base of the food chain
Zooplankton (dýrasvif) – Small, copepods most abundant
Benthos (botnlífverur) - Live on or in the bottom, many sessile
Benthic plants (botnþörungar) – kelp
Benthic animals (botndýr) – mostly invertebrates, shellfish
Nekton (sunddýr) – Can move well, fishes and marine mammals
Pelagic (uppsjávarlífverur ) – Live in the water mass
Demersal (botnfiskar) – Live close to the bottom

11. Species An extra way of life is found in the Arctic called Epontic.
Hreiðar Þór Valtýsson University of Akureyri 2016
An extra way of life is found in the Arctic called Epontic.
Species that live on the underside of ice (inverted bottom)

12. Species The phytoplankton is the base of the ecosystem
Hreiðar Þór Valtýsson University of Akureyri 2016
The phytoplankton is the base of the ecosystem
Single celled algae that cannot be seen by naked eyes
Eaten by zooplankton => eaten by small fish => eaten by seals => eaten by polar bears (simplyfied)
Dead zooplankton and animals sink to the bottom => eaten by benthic invertebrates => eaten by other animals

13. Ecology - Temperature Cold blooded animals
Hreiðar Þór Valtýsson University of Akureyri 2016
Cold blooded animals
Body temperature changes with environment
Thousands of enzymes are in the body
Their activity depends on temperature
The enzymes work faster as it gets warmer
They get more sluggish as it gets colder
If to cold some of the do not operate => animal dies
If to hot some of them cause damage => animal dies
Each animal (or rather its enzymes) has to adapt to a rather narrow temperature range

14. Ecology Arctic marine animals
Hreiðar Þór Valtýsson University of Akureyri 2016
Arctic marine animals
Tend to grow slow and live long => slow reproductive rate
A few groups that live in unstable environments the opposite, grow fast, live short => high reproductive rate
Many are able to store large quantities of energy rich lipids (fat) to survive high variability of food abundance – Arctic animals are generally fat
Also serves as insulation in mammals
Way to survive the winter
Tolerate it – one has to be tough
Migrate – one has to be easy traveler
Hibernate – one has to find a good spot

15. Ecology - Whales Warm blooded animals
Hreiðar Þór Valtýsson University of Akureyri 2016
Warm blooded animals
Constant internal temperature 37°C
Whales go where they want
Map of humpback whale migration

16. Ecology - Whales
Hreiðar Þór Valtýsson University of Akureyri 2016

17. Ecology - Seals Warm blooded animals Seals like to be in cold waters
Hreiðar Þór Valtýsson University of Akureyri 2016
Warm blooded animals
Seals like to be in cold waters
Having warm blood gives them advantage
Kovacs, K. M., Aguilar, A., Aurioles, D., Burkanov, V., Campagna, C., Gales, N., … Trillmich, F. (2012). Global threats to pinnipeds. Marine Mammal Science, 28(2), 414–436.

18. Ecology - Seals Arctic Subartic
Hreiðar Þór Valtýsson University of Akureyri 2016
The only species that breed in Icelandic waters are the common (15.000) and the grey seals (6.000)
Further north in the high Arctic they are even more abundant – these are vagrants here
Arctic
Subartic
Ringed seal - hringanóri
Harp seal - vöðuselur
Bearded seal - kampselur
Walrus - rostungur
Hooded seal - blöðruselur
Grey seal - útselur
Harbor seal - landselur

19. Ecology - Marine mammals
Hreiðar Þór Valtýsson University of Akureyri 2016
The Arctic is in fact a heaven for mammals and birds
Very few places in the world have as high densities of large mammals
Mammal hunting therefore very important for the people of the high Arctic
Due to the warm blood and active lifestyle these animals have an advantage in the cold
In comparison few species of cold blooded animals have managed to adapt to the Arctic although the few species that have can be really abundant, there is for example only one species of shark in the Arctic, Greenland shark
Polar bear- ísbjörn 19

20. Ecology Why are the Arctic and the Sub Arctic so productive?
Hreiðar Þór Valtýsson University of Akureyri 2016
Why are the Arctic and the Sub Arctic so productive?
It is cold and dark for a large part of the year !
It is because of high phytoplankton growth
Phytoplankton needs sunlight and nutrients (fertilizers)
Plenty of sunlight in the Arctic spring and summer
As nutrients are quickly used up by phytoplankton they would not be available in the upper layers under normal circumstances
This is the case in tropical waters and as a result they are very unproductive
To escape this problem the seawater needs to be mixed regularly to bring the nutrient rich deep waters up to the sunlight
This is the reason Arctic and Sub Arctic waters are so productive => next page

21. Ecology
Hreiðar Þór Valtýsson University of Akureyri 2016
Primary productivity in the ocean (cold or cold temperate waters)
Winter
Surface cooled by cold air => denser => sinks => nutrient rich deep waters up instead => mixing
However, limited sunlight => primary production none
Spring
Surface waters rich in nutrients after mixing in winter
Enough sunlight => primary production very high
Summer (this applies for the whole year in the tropics but is very short in the high Arctic)
Plenty of sunlight but ...
Surface waters warm => less dense than deep waters => stratification (no mixing) => algae finish up nutrients => Primary production low
Autumn
Surface waters are cooled by colder air => mixing again
Some sunlight => primary production rather high

22. Marine harvest High Arctic Few fish species Low biomass
Drawings: Jón Baldur Hlíðberg
Marine harvest
Hreiðar Þór Valtýsson University of Akureyri 2016
High Arctic
Few fish species
Low biomass
Fewer harvested
Low catches
Very few people
Mostly subsistence
High Arctic
Subarctic

23. Marine harvest High Arctic But the marine mammals ?
Drawings: Jón Baldur Hlíðberg
Marine harvest
Hreiðar Þór Valtýsson University of Akureyri 2016
High Arctic
But the marine mammals ?
Usually associate the Arctic with marine mammals
Very few places in the world have as high densities of large mammals
Mammal hunting therefore very important for the people of the high Arctic
Due to the warm blood and active lifestyle these animals have an advantage in the cold
Narwhal - Náhvalur
Bearded seal - kampselur
Harp seal - vöðuselur
Ringed seal - hringanóri
Hooded seal - blöðruselur
Beluga- Mjaldur
Walrus - rostungur
Northern right whale - Grænlandssléttbakur

24. Marine harvest But the SubArctic ? Many fish species High biomass
Drawings: Jón Baldur Hlíðberg
Marine harvest
Hreiðar Þór Valtýsson University of Akureyri 2016
But the SubArctic ?
Many fish species
High biomass
Some of the most important commercial fisheries in the world
High Arctic
Subarctic

25. Marine harvest High commercial fish catches
Hreiðar Þór Valtýsson University of Akureyri 2016
High commercial
fish catches
Subsistence hunting of abundant marine mammals
High commercial
fish catches
High commercial
fish catches

26. Climate change The Arctic is warming faster Global warming IPCC 2014
Hreiðar Þór Valtýsson University of Akureyri 2016
Global warming
IPCC 2014
The Arctic is warming faster

27. Climate change Atmospheric temperature 1830-2014 Icelandic Met Office
Hreiðar Þór Valtýsson University of Akureyri 2016
Atmospheric temperature
Icelandic Met Office
Ocean bottom temperature
Marine Research Institute
Ocean surface temperature
Marine Research Institute
Atmospheric temperature : N. Atl
Moberg et al 2005

28. 3. Key findings #4a Polar bears Mostly eat ice-living seals
Hreiðar Þór Valtýsson University of Akureyri 2016
Polar bears
Mostly eat ice-living seals
Among the animals that most dependent on ice
Unlikely to survive as a species if the sea ice disappears
Plus polar bears are long lived and at the top of the food chain
Therefore they accumulate toxic chemicals in the liver fat
These chemicals are persistent in the Arctic

29. 3. Key findings #4b Ice-dependent seals
Hreiðar Þór Valtýsson University of Akureyri 2016
Ice-dependent seals
Ringed seals probably the most affected
Spend their entire life on ice
Forage under or near the ice
Need enough ice to build lairs
Need ice cover to protect pups
Although the ringed seal is the most dependent on ice other high Arctic species would also suffer
Harbor and Grey seals from warmer climates would however thrive as new areas would be opened up for them

30. 3. Key findings #4c
Hreiðar Þór Valtýsson University of Akureyri 2016
Walrus
If the Arctic warms up walruses, other marine mammals and some birds might decline because of competition with warmer water fishes.
The walrus also depends on shallow waters, if the ice edge retreats from the continental shelf two bad things might happen to the walrus
Productivity is very high at the edge of the ice, this in turn supports rich bottom life that the walrus feeds on. If the edge retreats over deeper waters the walrus will no longer have the same food supply
The walrus uses the ice to rest on, therefore it needs to be close to the feeding grounds 31

31. 3. Key findings #4d
Hreiðar Þór Valtýsson University of Akureyri 2016
Algae
Most of the production in the lower Arctic is driven by ice-algae
Warming might (and probably has) cause these species to be replaced by less productive species 32

32. 3. Key findings #4e Additional threats
Hreiðar Þór Valtýsson University of Akureyri 2016
Additional threats
Warmer climates => increased risk of diseases
Animals in colder waters are not resistant to these
More precipitation is predicted and this can lead to increased pollution, but pollution is already a problem in the Arctic
Less ice => more shipping => more accidents => more pollution
More ultraviolet radiation largely due to depletion of ozone (key finding #9) => many species are vulnerable to this => less production 33

33. 3. Key findings #4 Summary of threats to Arctic species due to warming
Hreiðar Þór Valtýsson University of Akureyri 2016
Summary of threats to Arctic species due to warming
More competition with species from warmer waters
Less or different less suitable food
Loss of suitable habitat
Increased risk of diseases
More pollution
More human traffic
Conclusion
If the Arctic will continue to warm it will probably still be teaming with life
This will however be very different from the current as warmer water species will move in and pure Arctic species will retreat north
It is however impossible to retreat further north when you are on the North Pole 34

34. Next fisheries and climate change