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Boosting Salmon Numbers – is Stocking the Answer? 27th – 28th November 2013 Marriott Hotel, Glasgow.

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Presentation on theme: "Boosting Salmon Numbers – is Stocking the Answer? 27th – 28th November 2013 Marriott Hotel, Glasgow."— Presentation transcript:

1 Boosting Salmon Numbers – is Stocking the Answer? 27th – 28th November 2013 Marriott Hotel, Glasgow

2 IBIS/ Atlantic Salmon Trust Conference A two day conference presenting the cases “for and against” stocking No-one said “don’t stock!” 19 Presentations 19 Speakers, both scientists and fisheries managers A combination of scientific papers and case studies

3 IBIS/ Atlantic Salmon Trust Conference Day one Covered themes such as why stock?, the importance of genetics and the effectiveness of stocking 11 Talks across the day including two given by Eric Verspoor – one on the importance of genetics and a summary of the RCRP so far Included case studies from the Carron, the Bush, the Thames, the Lochy and the Connecticut rivers David Soloman postulated six reasons why fisheries managers might want to stock

4 IBIS/ Atlantic Salmon Trust Conference Kyle Young presented data showing damage to “fitness” of wild breeding caused by mixing with farmed stock Jon Gibb discussed the Lochy situation Jon Carr presented a summary of the ASF’s salmon recovery workshop Showed evidence for a range of hatchery techniques that can be used to improve survival in stocked fish Using a naturalistic environment “Wild exposure”

5 IBIS/ Atlantic Salmon Trust Conference Day two Eight talks covering the broad themes of what impacts will stocking have on wild populations?, climate change and salmon and the costs and benefits of stocking Jóhannes Hinriksson showed that stocking could work on a depleted river – the west Ranga in Iceland Put lots of fish in, got lots of fish out Pays for itself by licences – stocking accounts for 50-55% of the money raised and the rest is invested Able to charge £80 - £4,000 per rod per day Phil McGinnity illustrated the possible genetic implications of stocking on wild fish

6 IBIS/ Atlantic Salmon Trust Conference Mark Coulson and Roger Knight demonstrated that up to 2% of the salmon catch on the Spey was made up of hatchery fish 150 fish out of a yearly catch of 8,000 – 10,000! Have changed their hatchery policy accordingly Stephen Marsh-Smith showed how the Wye & Usk dealt with their salmon issues by fixing the environment Tom Reed asked whether salmon adaptation will keep pace with climate change Salmon have adapted before but they’ve NEVER had to adapt so fast before

7 IBIS/ Atlantic Salmon Trust Conference Summary David Soloman asked us to think about why we want to stock before we start General agreement that stocking shouldn’t be the first resort Stocking seen as a way of getting results quickly Stereotype is that anglers/ proprietors will call for it because it’s quick and they can see it working Stocking may be effective in the right circumstances Stocking isn’t necessarily giving you the returns that you think it is Stocking isn’t necessarily cost effective

8 IBIS/ Atlantic Salmon Trust Conference Stocking won’t overcome physical barriers Physical barriers depress the carrying capacity (K) of a river limiting fish numbers – removing the barrier will increase K increasing the population Stocking definitely has damaged studied wild populations and may, in fact, damage all populations Outbreeding depression Message is be careful If damage is caused it will be proportional to the level of stocking 1,000,000 fry in a small river could cause more damage than 5,000

9 IBIS/ Atlantic Salmon Trust Conference Ranching might be used to remove fishing pressure from the wild stocks as long as stocked fish are not allowed to breed Logistical/ cost issues associated with retrieving all stocked fish Quality of stocked fish more important than quantity

10 IBIS/ Atlantic Salmon Trust Conference Conclusions Have a clear understanding of what the problem is before you start Don’t reach for stocking as a first response Stocking is a tool in the fisheries manager’s toolbox but only that; one tool out of several – it cannot fix everything Have a very clear objective(s) before you begin to restore What do you want to achieve? How can you achieve the goal? Why do you want to stock? – is it just because it seems easy? Ask yourself before you begin “will my solution fix the problem?”

11 IBIS/ Atlantic Salmon Trust Conference If you do stock; be proportionate. Don’t over stock Have a way of monitoring the successes or failures Stocked fish must be identifiable – to gillies, to career anglers and to first timers Don’t be afraid to change your approach if it’s not working the way you thought it would Fix the problems on your river in a way appropriate to your river don’t just copy someone else…

12 IBIS/ Atlantic Salmon Trust Conference Questions?

13 IBIS/ Atlantic Salmon Trust Conference Why Stock? No salmon Not enough salmon Man made impact e.g. dam Selective breeding To produce fish for anglers (ranching) As decoys to attract straying fish

14 IBIS/ Atlantic Salmon Trust Conference Outbreeding depression Most salmon populations are so well adapted to their specific environment (river) that by cross breeding them you create hybrids which are less well adapted as you’ve brought in less “fit” genes – thus higher mortality Oykel eggs are resistant to acid flushes in the river, while eggs from the nearby (relatively) Shin are not (there are no acid flushes in the Shin). Shin eggs stocked into the Oykel would show a very high mortality. Hybrids would (theoretically) show a “middle” level of resistance


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