SAMARCH (SAlmonid MAnagement Round the CHannel)

On Friday the 25^th of January, three students from Arocampus Quest University in Rennes, Brittany came to the GWCT’s Salmon and Trout Research Centre at East Stoke, Dorset to present two videos (you can watch them below) and posters they had made to aid the recovery of tags from our tagged adult sea trout for the SAMARCH project. They filmed two videos, one for beach walkers who may find a tag on the beach and one for anglers who may catch one of our tagged sea trout. Its imperative that we get as many tags back from our sea trout because of the invaluable data they hold.

Last year when we trialled the process where we tagged 16 sea trout and recovered one tag from a beach in Cornwall and three tags from the fish trap on the river Bresle.

A huge thank you to Manon Fredout, Barbara Raguenet and Charlotte Buland for their hard work over the last few weeks in putting the two videos together.

Also thank you to two students from Bournemouth University, Ossi Turunen and Oskari Heimonen for their support with fieldwork on SAMARCH and helping to promote the project.

Source: SAMARCH Blog

By Adele Green, Bournemouth University

In April 2018 I completed a placement on the River Frome, Wareham, Dorset, as a research assistant from Bournemouth university in collaboration with the GWCT for SAMARCH. From late March to mid-May, the team aim to recapture a percentage sample of the previous years tagged fish. An acoustic bubble is positioned on the main river to divert fish down through the RST on the Mill Stream.

The shifts were run by a supervising fisheries scientist and one research assistant (i.e. myself). Day shifts began at 08:00 and night shifts at 20:00. At the start of the shifts, we entered the fluvarium to check water flow and ensure the trap was running correctly. The RST was then lowered into the river and environmental data and timings entered in the recording sheet. We set up the laptop to record any tagged fish caught, and a tub of anaesthetic solution to temporarily and humanely sedate the fish for efficient processing.

The RST was checked every 30 minutes for salmon (WSSM) and trout (TSM) which would then be netted out into a tub of freshwater. Any other species found were noted and released downstream. The salmon and trout were then put into the anaesthetic solution and the fisheries scientist would check them individually for a tag. Any tagged fish had their details entered onto the computer and scale samples taken; different sides for smolt and parr. Any that weren’t tagged, had their measurements logged, and scale samples were taken from one of each size. Multiple fish caught of the same size were recorded but had no scales samples taken. The scales are sent off to Exeter University and used to determine the sex of the fish and the growth and lifecycles at sea. The fish were placed back into the freshwater tub to readjust to conditions and then released safely downstream.

Going into this placement, I had no experience of working with fisheries and was eager to learn more about research processes and sampling techniques. I expected the night shifts to be busier than they were, with capture rates barely reaching 20, however this was likely due to the temperature not reaching 12°C. As the placement had many quiet periods, opportunities arose to learn more from the fisheries scientist of the biology and physiology of salmon and trout, and the small morphological differences to assess when identifying the species.

Catching the occasional minnow and roach prompted discussions of the ecology of the river, with eels, perch and dace also caught throughout the run. I learnt more about the lifecycles of salmon and trout, their migration patterns, and their evolutionary responses to risk and challenges. For example, how the majority of smolt migration occurs during the night, likely due to adaptation or behavioural decision making to decrease predation risk and/or increase feeding due to a higher abundance of food, and so day shifts are likely to be much quieter.

Whilst working with supervising scientist, Bill Beaumont, I gained further knowledge of tagging techniques used to track fish. For example, the functional differences between acoustic and radio tagging, how they collect the data, and the environmental conditions that affect them. Whilst visiting the lab between processing times, I was shown how to read the information contained in the fish scales; analysing scales is similar to observing tree rings with aging and growth, condensed lines indicate winter growth, spread/spacious lines indicate summer growth and erosion on these lines indicate spawning. These quiet periods between trap checks also gave opportunity to engage with other scientists in the field to learn more about their careers. This provided me with important directional knowledge and contacts for experience in fisheries ecology and management.

Source: SAMARCH Blog

By Ossi Turunen, Bournemouth University

I attended the Global Engagement Fusion Seminar at Bournemouth University on 24th January to present and share my own experiences with the SAMARCH project. The seminar was hosted by BU academics Professor Genoveva Esteban and Dr Dan Franklin whom both presented their on-going and forthcoming work with the Interreg Channel Programme.

I had prepared, in collaboration with another BU student, Oskari Heimonen, a short presentation to highlight the great placement opportunities SAMARCH has to offer. Other presentations were given by other BU academics and our French peers from Agro Campus Ouest.

This Global Engagement Fusion Seminar was first of its kind and from my perspective, especially after discussing with all the other presenters and also with the audience, the seminar was a great success. In the future the upcoming SAMARCH Newsletter will keep you updated on events like this!

Source: SAMARCH Blog

SAMARCH is beginning to unravel the mysteries of sea trout at sea. We have started to analyse the data from the four DST’s recovered this summer and have looked at the depth data recorded, below is a graph of a Tamar sea trout showing its maximum and minimum swimming depths over a 10 day period. The sea trout was caught and tagged in the Tamar in mid-December 2017, it then went to sea in mid-January and in mid-May the fish died and the tag floated to the surface and was washed up on Pentewan Beach, near St Austell Cornwall. The tag was found by a beach walker who posted the tag to us in return for a £50 reward.

The preliminary data reveals that the fish spent much of the night time near the surface, but during the day undertook multiple dives to depths of up to 50m and that it spent at least 80% of daylight hours at depth greater than 10m. This new data questions the effectiveness of current rules to protect sea trout at sea which is that no net should be set within three or five meters of the surface.

A further 300 sea trout will be tagged between December 2018 and January 2019, that will bring more data to improve the sea trout management in coastal waters.

Source: SAMARCH Blog

I have recently arrived from Canada and started a PhD position with Bournemouth University and the Salmon and Trout Research Centre at GWCT as part of the SAMARCH project. Before moving to England, I lived in Iceland, where I completed my Master’s degree studying trophic interactions between rainbow trout (Oncorhynchus mykiss), sea trout (Salmo trutta), and Arctic charr (Salvelinus alpinus).

For my PhD thesis I will test the hypothesis that current declines in anadromous salmonid populations are a function of changes in their migration phenology. More specifically, I will be studying Atlantic salmon (Salmo salar) in the River Frome, and am interested in what intrinsic factors (such as the length and weight of juvenile salmon) and extrinsic factors (such as water temperature) affect the likelihood of salmon surviving to adulthood and migrating back to their natal rivers, where they lay their eggs. Atlantic salmon have a complicated life cycle, and there is still a lot to learn about their long migrations. I hope that the findings from my research will help inform management and conservation efforts for salmon in this region.

Source: SAMARCH Blog

This week we deployed two rotary screw traps (RST) into the upper Tamar catchment to catch sea trout kelts on their post spawning migration back to sea. The traps are currently anchored in the middle of pools ready to be positioned for trapping once spawning commences later this month. The RST work when they are positioned in a narrow channel of fast running water, with enough flow to rotate the drum, the fish swims into the drum, usually in coloured water or at night and gets slowly rotated back into a collection chamber at the rear of the trap. It will mean long cold nights of work for GWCT staff – brrrrrrrrrrr.

The trapped kelts will have two tags inserted into their body cavity, an acoustic tag and a data storage tag (DST). The acoustic tag will tell us when the fish reaches the lower river and goes out to sea and upon recovery the DST will tell us how deep the fish swims and its location at sea. We trialled the recovery of the tags last winter, where we tagged 16 sea trout kelts, and recovered tags from 4 sea trout which are revealing some fascinating data on the depths these fish swim at sea.

Source: SAMARCH Blogs

By Ossi Turunen, Bournemouth University

I attended a Career Spotlight event at Bournemouth University on Monday 15th October to present my own experiences with the SAMARCH project and to meet new inspiring people. The event started with a keynote speaker Brian Heppenstal from Hengistsbury Head followed by a panel discussion by Bournemouth University graduates and academics, including Professor Genoveva Esteban who also covered some of the SAMARCH project during the discussion.

The event ended in a networking session where current students were able to ask more questions from the speakers and find new career opportunities. I had made a poster about my SAMARCH placement which I presented in the networking session. With Professor Esteban and Jack Dazley we had the chance to discuss with people about SAMARCH and promote the placement opportunities.

Source: SAMARCH Blogs