Page Content:
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+ Scotland's Seals
+ A Scottish Perspective (Diversity, Topography).
+ A Scottish Sea Loch as an Example.
+ No Take Zones.
+ Changes to Scottish Legislation: Stop Seal Shooting.
A short background to the seals found in Scotland, touching on numbers of seals and how they are recorded. Information on the shooting of seals and a more in-depth account on recording methods can be found on the Sustainable Seas page.
Seals are classified in the suborder, - pinnipeds (‘fin or flipper’ footed), they are “dog-like” carnivorous mammals. There are three families found in the Suborder; Walrus (Odobenidae), sealions and fur seals, the eared seals (Otariidae) and the true seals (Phocidae). There are five sub-species of Phocidae; Phoca vitulina.
Scotland has two resident breeding species both in the Family of Phocidae. The European subspecies of Common or Harbour Seal; Phoca vitulina vitulina and the Atlantic Grey Seal; Halicoerus grypus.
The European subspecies; Phoca vitulina vitulina is found in Scotland. The subspecies classification is important as the Common seals are geographically separated from each other and this becomes relevant when the numbers in the population are being discussed.
I.D. Common seals look somewhat like a Labrador without ears, they have a dip on the forehead and their nostrils tend to form a ‘V’. The true seals cannot ‘walk’ on their hind limbs and use their hind limbs for propulsion, pectoral flippers for turning and holding. They can measure up to two metres and weight varies between 65 – 150Kgs.
“Despite being called “common”, they (European subspecies) are actually less common than grey seals”. Wildlife Trust.
We are responsible for the UK seal populations which is approximately 45-50% of the European subspecies; 33,400 Common seals are found in the UK, 90% of which are in Scotland.
The larger Grey Seal Halicoerus grypus is only found in the eastern and western coastal fringes of the Atlantic. They are among the rarest seals in the world, with approximately 40% of the global population around 120,000 found in the UK, 90% of these are in Scotland.
I.D. Grey seals have a ‘Roman’ nose and their nostrils are close to parallel; not joining near the mouth, they are larger than common seals, especially the males, which can be more than two metres, less for females approximately 180cm. Males can be around 230Kgs, females 150Kg.
The methods of counting seals can be dry but important as we need stats to give an indication of trends, especially when some commercial industries blame seals for a lack of fish, calling for culls and salmon farms blame them for damage, we have found that often both matters are falsely reported.
Halicoerus grypus
Phoca vitulina vitulina
Under the Conservation of Seals Act 1970 for England and Wales and the Marine (Scotland) Act 2010 the Natural Environment Research Council has a duty to give scientific advice to government, the Special Committee on Seals was formulated to report on the management of seal populations and the scientific research is carried out by the Sea Mammal Research Unit based in St Andrews, Scotland.
Grey and Common seals are counted differently, Greys are counted during pupping season where the ‘white-coats’(pups) are clearly visible, from fixed wing aircraft. Once counted a mathematical model is applied in order to give a total figure, it is worth noting that this modelling system has changed over time, making direct comparison more difficult. Common seals, being better camouflaged with rocks are counted using a thermal imaging camera, usually from a helicopter. Counts from boats can also be used.
Not only have methods changed but the frequency of counts has reduced, resulting in greater uncertainties. This makes comparisons in relation to population trends with high levels of confidence more problematic. Reports of ‘population explosions’ require careful scrutiny, what has been apparent in some areas of perceived increase has been due to relocation of the seals.
In general Greys have increased, especially in the east. That said Scotland has around 40% of the world population and globally they are as rare as African elephants, we are custodians for future generations. We don’t have a baseline population, pre-hunt figure, where they were hunted to near local extinction, around 500 individuals, so it is subjective to ascertain what is the ‘norm’.
The European sub-species of Common seals are said to be stable on the west coast, but we maintain that depends on where the boundaries are drawn. This is similar to changing political boundaries which can favour a particular party. When Marine Concern submitted EC complaints, Common seal populations in some west coast areas were reduced by half and this includes at least one Special Area of Conservation for Common seals. The populations in the Northern Isles and east coast are in decline. During the PDV outbreaks some areas were subject to a massive decline.
We have requested information regarding the most up to date data for specific areas/locations, we will update this when we can.
Scotland's West Coast
The western coastal fringes of Europe are influenced by relatively warm ocean currents, the Gulf Stream separates and it is the North Atlantic Drift Current that heads towards Scotland, this has a warming effect on the climate, with high levels of precipitation. The west coast of Scotland is influenced by both northern and southern waters, a Boreal current meets the Continental Shelf Current from the south, this produces an up-welling of nutrients and an abundance of phytoplankton and zooplankton forming the base of the food chain. As a result, large marine mammals are found here; important numbers of Pinnipeds and Cetaceans.
A Gannet out at sea on the west coast.
Extreme Topography
Scotland's climate and coastal regions are inundated with inlets, some of which resemble fjoridic and fjardic regions of Norway, Scotland's coastline is huge, Argyll, a mid county, alone has a coastline longer than that of France. A very special area which includes species at their northern and southern limits, species diversity is equal to the warm coral reefs.
A Common Dolphin in the Sea of the Hebrides.
Species Diversity
The west coast of Scotland is a 'hot-spot' for cetaceans (whales, dolphins and porpoise), visitors include the World's second largest fish, the basking shark, along with rarer deep water rays. Scotland is home to two species of seal, the Common and Grey seals. The British Isles accounted for around 40% of the European Common (or Harbour) Seal, this has declined to around 30% in recent years. About 40% of the Global population of Grey or Atlantic Seals are resident here as well.
A rock pool on Staffa.
Scottish ecosystems are as vital as they are diverse.
Scottish Sea Lochs and Loch Etive (An Example)
Much of Scotland's west coast is highly indented, convoluted with fjordic sealochs. Fjords are deep and steep sided with sills at their entrance limiting the inflow of seawater. Often brackish due to the immense runoff in western climes. This leads to special and difficult conditions which can contain isolated deep waters. Even the sediments are special holding varvic deposits which can give a snap-shot in time.
Highlighting Loch Etive as an example, situated midway on the west coast is an outstanding example of a Scottish fjoridic sea-loch, the pictures below are all taken in the Loch Etive water catchment area.
High up on Rannoch moor, home to a former glacial ice field rivers feed to the east, Glen Coe and Loch Etive. Peaty waters create an eerie brown tinge to the surface waters of the sea loch.
Loch Etive's upper basin, with depths exceeding 140m and a narrow sill at Bonawe Narrows. Deep waters here can be isolated for well over a year. These can become anoxic.
Tidal flows can be strong with over a metre difference in height either side of the Connel Bridge, the Falls of Lora.
With a flow exceeding 10 knots salt wedges form, overfalls, eddies and mini whirlpools.
Loch Etive has numerous fish farms, the nearest seen here is a mussel farm and in the distance a fin-fish farm.
Not all commercial practices are safe. One of the problems when commercial companies operate in remote, rural, marine locations.
Fin-fish, especially salmon farming is a big and growing industry along the Scottish west coast. Currently however, it appears that profit overcomes environmental concerns. Planning consents are conducted by those working from a terrestrial background with little allowable input from individuals or environmental groups. Government and government agencies appear hell-bent on supporting growth, especially with China's insatiable taste for salmon, but a one percent increase in supplying China would require a 50% increase in Scottish production. In its current form, that is not sustainable. The potential for environmental damage on a huge scale is very real.
These buoys support mussel lines. Mussel farming has always been considered one of the more benign methods of marine aquaculture but once again caution is needed and it has not been as more and larger farms become established.
Sea lochs and oceans, have a carrying capacity, a limit to what they can sustain without adverse issues. It has been suggested that Loch Etive has surpassed its carrying capacity, yet still they allow expansion.
Mussels syphon water; in doing so they feed by extracting particles from the water and they are very efficient, multiply that by millions and effectively the loch has one highly efficient 'cleaning' mechanism. However, when that means mass removal of other species the problem can become great.
In recent years a previously unseen mussel competed with the commercial varity,
Mytilus trossulus out-competing with the current commercial mussel species Mytilus edulis,
but this new mussel (actually turned out to be the original species not seen since the last ice age) species contained only 10% meat and shells were so fragile that they could not be harvested using the current commercial methods. The problem was so bad that the industry voluntarily ceased production in the hope that the edible variety might return. For further reading.
Boats and moorings in Loch Etive were inundated with mussel spat (young mussels), so much so that it could become a problem. Boats moored outside of the loch but close-by had far fewer mussels and a combination of acorn barnacles and algae. Barnacles and algae in the loch were becoming less apparent. An altered ecosystem.
Is this a case of too much? More research is needed but the 'Precautionary Principle' as enshrined in the Rio 'Earth' Summit should have been utilised, often in Scotland's marine planning it is not.
Commercial activities need to look more closely at the very environment which supports it. Salmon farming is currently one of the worst offenders, where profit comes first even at the cost of the industry.
Peru and Chile have seen catastrophic collapses, Scottish salmon farming could be going the same way without enforced legislation.
It is not just aquaculture, mobile fisheries such as scallop dredging and benthic trawling destroy fish breeding grounds, few areas are given adequate protection.
There is room in our seas for production, activities and the environment such as the kayakers seen in the overfalls in the Falls of Lora, but only with real care.
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NB. All photographic stills are copyright © of Mark-MC.