Marine Scotland blog

News from Marine Scotland

March 30, 2016
by Ruth Allen

Joint Warrior Training Activity: 11th to 23rd April 2016

Joint Warrior (JW) 161, will take place between 11th and 23th April 2016 and will comprise of a programme of exercises conducted by land forces, warships, submarines and aircraft across the UK. The maritime element is focussed in the offshore and coastal waters to the north east, north and north west of Scotland.

Further Information

March 23, 2016
by Ruth Allen

Round-up of the latest Scottish Marine & Freshwater Science publications

March has seen a bumper number of Scottish Marine & Freshwater Science publications being released. In case you’ve missed any, here they are:

  • Measurement of Hearing in the Atlantic salmon (Salmo salar): Scottish Marine and Freshwater Science Vol 7 No 11
  • Collection of Data to Inform the Implementation of a Discards Ban: Scottish Marine and Freshwater Science Vol 7 No 12
  • Spring salmon on the River South Esk, Scotland: Scottish Marine and Freshwater Science Vol 7 No 10
  • Technical, Logistical, and Economic Considerations for the Development and Implementation of a Scottish Salmon Counter Network: Scottish Marine and Freshwater Science Vol 7 No 2
  • Swimming depth of sea trout: Scottish Marine and Freshwater Science Vol 7 No 13
  •  Crab and lobster fisheries in Scotland: results of stock assessments 2009-2012: Scottish Marine and Freshwater Science Vol 7 No 9

For more details of other publications in this series, check out the Scottish Marine & Freshwater Science publications website.


March 22, 2016
by Ruth Allen

New report on the swimming depth of sea trout published

The potential risk which marine renewable developments pose to animals at sea, including fish, is partly dependent on their swimming depth. For example, fish species which predominantly occupy space close to the surface will be at less risk from bottom-mounted tidal turbines than fish species that have a bentho-pelagic lifestyle.

The sea trout is an important species which commonly occurs in development areas for renewable energy development, but existing published information on its swimming depth was sparse and not in an ideal format for risk assessment. The need for information led to Marine Scotland contacting Jóhannes Sturlaugsson to work on data he had collected in Icelandic waters in various studies on sea trout during their sea migration using data storage tags (DSTs).

The work consisted of him compiling and analysing the raw data on swimming depth into a format suitable for use in risk assessments and gives detailed descriptions of the observed main patterns in vertical distribution and the potential environmental and behavioural drivers for the swimming behaviour observed.

The analysed data shows that the sea trout were close to the surface much of the time, with some time being spent at greater depths. Separate depth profile data are presented for each study year, and overall 81.49% of the time was spent at depths between 0-5m, and 16.34% at depths between 5.1 and 10m.

Further Information

March 22, 2016
by Ruth Allen

Pilot Pentland Firth and Orkney Waters Marine Spatial Plan approved

The pilot Pentland Firth and Orkney Waters Marine Spatial Plan has now been finalised following endorsement by Orkney Islands Council and the Highland Council and ministerial approval.

Now the Plan has been approved it will be used by the Marine Scotland Licensing Operations Team as a material consideration in the determination of marine licensing and section 36 consent applications within the PFOW area.

The Highland Council and Orkney Islands Council have adopted the pilot Plan as non-statutory planning guidance, acknowledging the status of the Plan as a material consideration in the determination of relevant planning applications. Orkney Islands Council has also adopted the Plan as a material consideration in the determination of works licence applications in the Orkney Harbour Area.

What will happen now?

All these documents will be available to future Marine Planning Partnerships to help inform the development of  statutory Regional Marine Plans. The working group will also monitor how the pilot Plan is used to support marine licensing, works licence and planning decisions within their respective organisations.

It is likely that development of the Orkney statutory Regional Marine Plan will proceed before the North Coast and will be led by Orkney Islands Council. During 2016, Orkney Islands Council will engage with Marine Scotland, Elected Members and wider stakeholders to canvas views on the future delivery of statutory regional marine planning in Orkney. In the meantime, the statutory National Marine Plan and the non-statutory pilot PFOW plan can be used by regulators and wider stakeholders interested in projects or activities in Orkney and the north Caithness and Sutherland coast.

And finally….

The working group would like to take this opportunity to thank everyone who has contributed to the development of the Plan. This work would not have been possible without the input we have received from a wide range of knowledgeable people. We will continue to keep you informed of any developments over the coming months.

Further Information

The Plan and all the associated documents are available on the Pentland Firth and Orkney Waters Marine Spatial Plan website

The most recently added documents added are:

  • Pilot Pentland Firth and Orkney Waters Marine Spatial Plan
  • Consultation Analysis and Modifications Report
  • Lessons Learned
  • Regional Locational Guidance
  • Strategic Environmental Assessment Post-Adoption
  • Statement
  • Habitats Regulations Appraisal Record
  • Business and Regulatory Impact Assessment
  • Equality Impact Assessment
  •  Summary document

March 22, 2016
by Ruth Allen

New report published on the hearing of salmon

Underwater noise in the sea has the potential to affect marine animals, including fish.

A new report published by Marine Scotland Science, Measurement of Hearing in the Atlantic salmon (Salmo salar) using Auditory Evoked Potentials, and effects of Pile Driving Playback on salmon Behaviour and Physiology, describes measurements of the hearing capability of salmon in experimental aquaria, and of their response to play-backs of pile driving noise.

Anthropogenic (human-generated) noise is widespread in aquatic environments and is increasing in prevalence and intensity. Aquatic noise-generating activities include high intensity air guns used for seismic exploration, chronic low-frequency noise from shipping, and noise produced during construction and operation of offshore energy installations. The noise produced during such activities is very different to sounds that typically arise from natural sources.

The continued development of Marine Renewable Energy Devices in Scottish coastal waters is recognised as an important step in the UK’s drive for clean, low carbon energy and the unavoidable noise caused by such developments, principally pile driving used in the construction of offshore wind farms, has raised concerns about the potential impact of noise on sensitive marine species.

In experiments carried out with salmon in captivity to determine their hearing capabilities, they appear to have hearing abilities that generally concur with previous studies.  In addition, salmon showed little behavioural response to pile driving noise. There was no clear startle response, and no clear avoidance behaviour. Equally, there was no evidence of physiological response through change active metabolic rate or oxygen consumption rate.

Further Information

March 21, 2016
by Lyndsay Cruickshank

Celebrating 50 years of the Girnock Burn Fish trap

Taken a few metres upstream from the Girnock trap April, 1970.  Breaking the ice up to clear the trap.2016 marks the 50th anniversary of the Girnock Burn fish trap on the River Dee in Aberdeenshire. The Girnock Burn fish trap is one of only three long-term fish population monitoring facilities in Scotland where detailed information on adult and emigrant numbers, sizes and ages of Atlantic salmon is obtained by Marine Scotland Science (MSS) (the others being the Baddoch Burn on the Dee and the River North Esk).

During the early 1960s, a network of three fish traps was planned for the River Dee with the aim of studying Atlantic salmon populations in the lower, middle and upper reaches of the river, approximating to late, middle and early running stocks respectively. However, only the Girnock Burn traps were instigated at this time. The site comprises a pair of fixed traps built around the structure of an old weir that historically diverted water from the burn to power a local sawmill. Throughout the 1960s and 1970s, the trap was run by a four-man team who lived locally and ensured uninterrupted operation of the trap throughout the year. Reductions in trapping effort during the early 1980s resulted in staff being relocated to the Freshwater Fisheries Laboratory in Pitlochry, and the trap is now operated remotely from there. Several webcams on-site enable continuous monitoring of the conditions which allow the current complement of staff to concentrate site visits to periods where fish are likely to be caught in the traps (i.e. high flows).

Girnock Burn fish trap_adult trap in the foreground and the juvenile trap in the background

The Girnock Burn is dominated by spring-run multi-sea-winter Atlantic salmon, the stock component that has been of greatest concern in recent decades, and the traps catch adult salmon returning to the stream to spawn and juvenile salmon emigrating seaward. The facility provides key data for guiding Government policy on regulating fisheries to conserve the Scottish spring stock.  In addition to the number of fish passing through these traps, important information is also obtained on size, age and sex of the fish, and an annual electrofishing programme provides information on juvenile abundance and performance. Taken together these data make the Girnock a uniquely valuable research and monitoring facility representing the longest comprehensive dataset of Atlantic salmon populations. The Girnock has been the focus of > 100 peer-reviewed papers covering a broad range of topics including fisheries, hydrology, hydrochemistry, river temperature, invertebrate drift and productivity. The site acts as a focus for inter-disciplinary research supporting collaborations with the Universities of Aberdeen, Birmingham and Strathclyde. Data from the site also contributes towards national and international assessments of stock status through International Council for the Exploration of the Sea (ICES)

The length of the Girnock datasets represents both a fantastic asset and a data management challenge. The bulk of the Girnock data pre-dates the use of computers, with raw data collected in books, notepads, paper files and maps. These comprehensive records were never fully documented, archived, and quality controlled in a single location and format until 2012, when a two year programme of work carefully quality controlled, validated, and where necessary, entered data into the Marine Scotland FishObs database. This exercise has produced a series of definitive Girnock datasets for analysis which are readily available to download from the Marine Scotland website.

With the Girnock set to undergo a programme of trap maintenance over summer, there is every chance that the trap will operate for the coming 50-years and add to the already valuable long-term dataset underpinning advice on fish and fisheries to Scottish Government, supporting national and international salmon and eel population assessments, the development of assessment tools, and understanding of the effects of long-term climate change on fish populations.

Ross Glover
Fisheries Biologist / Girnock & Baddoch Trap Manager

Further Information

March 18, 2016
by Lyndsay Cruickshank

Model Success for Oceanographers

The Scottish Government has funded a new hydrodynamic model, called the Scottish Shelf Model (SSM), developed under the direction of Marine Scotland scientists, to describe the physical marine environment around our firths and sea lochs at the coast, up to the edge of the continental shelf and into the North Sea.

Hydrodynamic models are computer programs that simulate the currents, temperature, salinity and other properties of our seas and are an essential tool for studying our oceans.

The SSM has  applications in fisheries, aquaculture, renewable energy, emergency response, marine planning, ecology and conservation. It will be of particular interest to socio-economic sectors, such as aquaculture and marine renewable energy, where a high spatial resolution is required to adequately understand the complex physical processes in their regions of interest.

Developed over three years, the SSM has a vast array of potential applications to all areas of marine science and can give a detailed spatial picture of the water properties, which would be unobtainable from observations alone.
So far, the model has been used to provide tidal energy resource maps (such as that shown below), wave resource maps around Orkney, and to study the connectivity of fish farm management areas. However, work is currently underway to use the SSM to model the effect of tidal turbines on the physical marine environment.

Tidal Energy Resource Map for the Pentland Firth and Orkney Waters

Project Manager Tracy McCollin commented: “The project team has gone through a very interesting, challenging and technical process to deliver the Scottish Shelf Model and we are all looking forward to seeing it contribute to a wide range of uses. This is a very powerful tool and will play an important role in the further development of marine science in Scotland. ”


Further Information:

Partners in the Scottish Shelf Model are:


March 10, 2016
by Lyndsay Cruickshank

Our Inspirational Women in Science

To further inspire and promote the role of women in STEM roles, two of Marine Scotland Science’s highly experienced oceanographers will be taking part in Scottish science events this and next month.

Resident Oceanographer and ScienceGrrl Dr Sarah Hughes will be participating in British Science Week, the UK’s annual celebration of Science, Technology, Engineering and Maths, from 11th to the 20th March with “The Untold Story of Aberdeen’s Women in Science” and “Busting the Myth”. Both events are free and open to all.  Dr Hughes will be sharing accounts of inspirational moments, struggles and triumphs from her career in science and will later be busting some science myths with her fellow ScienceGrrls.

Continuing on with the appreciation of all things STEM, the Edinburgh International Science Festival 2016 begins on 26th March and continues through to the 10th April.

Dr Bee Berx, fellow Oceanographer in Marine Scotland Science will be participating in a hot topic discussion looking at the effect of plastics in our oceans, ocean tracking and the food chain.  Our global oceans are teeming with all sorts of life, some of which hasn’t even been discovered yet, so dive into our oceans and discover how they are under threat of turning into an Ocean Junkyard.


Further Information:

March 4, 2016
by Lyndsay Cruickshank

MRV Alba na Mara: Survey 0316A Programme

Duration: 7-21 March 2016


  • BT 201 Prawn net – rigged with separator grid and two 80 mm codends
  • Trawl doors
  • Sweeps, bridles, backstrops and pennants
  • Spare netting and twine
  • Live capture codends
  • PSL5000 light unit x 2
  • 4 x 10m side emitting light cables
  • Battery pods
  • Video Cameras
  • Flashback recorders and housing
  • Pyramid camera frames
  • TechnoSmart AXY tilt sensor
  • Scanmar units – wing, door, height and depth
  • Catch bins
  • Catch sorting table


  • Investigate whether light influences fish behaviour in the extension of the trawl.
  • Obtain video footage of the separator lighting grid.
  • If time permits at the end of the cruise, carry out live capture of haddock for fish behaviour work back at the lab.

Equipment will be loaded onto MRV Alba na Mara at Fraserburgh on 4 March 2016, where the trawl will be rigged onto the net drum.  Scientific staff will join Alba on the evening of 6 March, then leave harbour and steam to fishing grounds approximately 9nm east of Aberdeen to commence work on 7 March.  A number of short hauls will be carried out to ensure the separator grid in the trawl is rigged correctly through observations with video cameras mounted on the trawl and analysis of a tilt sensor mounted on the grid.  After the rigging trials are complete fish behaviour trials will commence.  If sufficient valid fish behaviour hauls are completed during the survey, then some time at the end of the trip will be used for live fish capture.  Alba will return to Fraserburgh on the evening of 20 March to unload equipment and scientific personnel on 21March.

Fish Behaviour Trials
The BT201 prawn trawl is fitted with a horizontal separator grid in the extension that leads to two separate 80 mm codends.  There will be two light fibre lines permanently attached to the grid, one illuminating the upper half and one illuminating the lower half of the grid.  This will allow four lighting variables to be trialled: upper light on, lower light on, both lights on and both lights off.  The lighting variable will be changed between hauls so that each gets an even distribution of the working period throughout the survey.  The PSL5000 light unit and 12V battery pack cannot be wound onto the net drum so will be attached to/detached from each light fibre cable during shooting/hauling as required.

The working hours during the survey will be midday to midnight.  This is to allow hauls to be conducted in daylight and dark conditions.  Around four or five fishing hauls will be carried out each day, with the aim of achieving at least two light and two dark hauls per day.  Hauls will be 45 minutes long initially, with the potential to be adjusted depending on the catch volume.  The net will be towed at three knots.  Scanmar units will be used to monitor wing spread, door spread, and headline height and depth during each haul.

Large bins will be used on deck to receive and store the catch from the separate codends.  The catch will be sorted into key species, weighed and individual total length measurements recorded.

Live Fish Capture
The separator grid and twin codends will be replaced with the live capture codend.  The tows will last 20 minutes and the net will be hauled back slowly.  The catch will be sorted on-board with healthy haddock in good condition being placed in tanks of aerated seawater.  The fish will be handed over to MSS aquarium personnel once in harbour for transporting back to the marine lab.

Marine Litter
Any marine litter brought onboard during trawling operations will be documented before being placed into “KIMO Fishing for Litter” bags.  At the end of the survey the bags will be deposited safely on the quayside to be collected for disposal.