The Davis Strait - DCE - Nationalt Center for Miljø og Energi

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Marine mammals – distribution and abundance, relationship to sea ice,
stock identity and movement, general biological knowledge of less known
species and of endangered species
Relevance: Marine mammals are sensitive to oil spills and to anthropogenic
noise. To mitigate impacts and understand the consequences of these impacts
it is important to know where marine mammals are, why they are
there and what their status is.
Methods: Tracking by means of satellite transmitters and bio-loggers, dedicated
surveys, passive acoustic monitoring, molecular studies and markrecapture
(tags, biopsies or photo-ID, depending of species).
Marine mammals – reactions to noise from drilling and seismic studies
Relevance: Marine mammals are sensitive to noise and there is a risk of displacement
from critical habitats especially for whales if there is a cumulative
impact from concurrent activities in several licence blocks. Knowledge on
reaction distance and the potential for habituation to noise is important.
Methods: Field studies, passive acoustic monitoring, satellite tracking.
12.2 Knowledge gaps generic to the arctic
The effects of oil and different oil components on marine organisms have to
some degree been studied in laboratories. However, effects in the field and
especially in the Arctic are less well known and because the Arctic food web
is dependent on a few key species, effects on these would be very relevant to
study in order to assess and mitigate potential impacts. Assessment criteria
and adequate monitoring strategies should be established.
Below some important issues that should be addressed before production
activities are initiated in Greenland are listed. Some of these should be addressed
by international research cooperation. Many relate to how spills and
releases behave and impact organisms under Arctic conditions.
In relation to oil spills some important issues to address include:
• Biological effects and sensitivity to PAHs and other oil components of
key species (e.g. sandeel, capelin) under Arctic conditions
• Rate of degradation of oil and chemicals in Arctic water and sediment
• Oil vapours and their effects on marine mammals.
Similar issues relating to produced water are:
• Fate, behaviour and toxicity of produced water in cold and ice-covered
waters
• Biological effects and sensitivity of key species (e.g. sandeel, capelin) to
the different components of produced water.
Interaction of contaminants:
• There are knowledge gaps concerning the interactions between impacts
of oil related pollution and other contaminants such as POPs and heavy
metals in relevant species living in the assessment area. Integrated studies
on these issues are needed.