Sophie Elliott 1*, Bill Turrell 2, Mike Heath 3 and David Bailey 1 University of Glasgow 1, Marine...
3
Sophie Elliott 1* , Bill Turrell 2 , Mike Heath 3 and David Bailey 1 University of Glasgow 1 , Marine Scotland Science 2 , University of Strathclyde 3 The Effect of Fine Scale Habitat Characteristics on The Effect of Fine Scale Habitat Characteristics on the Populations Density of Juvenile Gadoid Fishes the Populations Density of Juvenile Gadoid Fishes Acknowledgments and funding : : COAST, Millport FSC and Bailey research group
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Transcript of Sophie Elliott 1*, Bill Turrell 2, Mike Heath 3 and David Bailey 1 University of Glasgow 1, Marine...
Sophie Elliott1*, Bill Turrell2, Mike Heath3 and David Bailey1
University of Glasgow1, Marine Scotland Science2, University of Strathclyde3
The Effect of Fine Scale Habitat Characteristics on the The Effect of Fine Scale Habitat Characteristics on the Populations Density of Juvenile Gadoid FishesPopulations Density of Juvenile Gadoid Fishes
Acknowledgments and funding::COAST, Millport FSC and Bailey research group
BackgroundBackground Research QuestionsResearch Questions• Does the availability of important habitats affect recruitment
success?
• Should certain habitats be protected to improve recruitment success?
• Decline in demersal fish stocks
• Lack of recovery
• Little understanding of gadoid nursery areas
McIntryre et al, 2012
Gadus morhua Melanogrammus aeglefinus Merlangius merlangus
• Stereo Baited Remote Underwater Video cameras• Event measure software (record MaxN and size
measurements)• Variety of different habitats and abiotic conditions
MethodMethod• Within the Firth of Clyde
- South Arran Nature Conservation MPA
Study AreaStudy Area
ResultsResults
Linear model, p<0.001Haddock length ~ Julian date
Linear model, p<0.001Cod length ~ Julian date + Depth + Wave fetch + Depth * Wave fetch
Length ChangeLength ChangeRelative AbundanceRelative Abundance
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Negative binomial model p<0.001Cod MaxN~ Habitat type + Julian date+ Depth + Wave fetch
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Negative binomial model p<0.001Haddock MaxN~ Habitat type + Julian date+ Depth + Richness
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ConclusionsConclusions• A significant difference in relative abundance of juvenile cod was seen between
habitat type• A decrease in cod and whiting was seen over the summer period although pulse
recruitment is occurring• Habitat had no effect on the relative abundance of haddock and whiting• An increase in size of individuals was seen in over the summer in all three species
Zero inflated Poisson model p<0.01Whiting MaxN~ Richness + Julian date
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• Strengthen the data set and compare to year one• Collect data within a broader depth range• Looking at behavioural changes within habitats (such
as shoaling as an antipredator technique) • Otolith analysis to age fish
Next StepsNext Steps
Linear model, p<0.01Whiting length ~ Julian date + Depth
