marine surveys (fisheries), UVCs & Ascension Island Flashcards
term 2 week 1
1
Q
Sea Fisheries Committees
(SFCs)
A
- originally 11 SFCs with Isles of Scilly joining in the 1970s
- only in England & Wales
- managing out to 3nm from 1983 baselines
- in 2000 – national budget of £5.2m
- powers conferred from Sea Fish Regulation Act 1967
- officers very often ex police/navy or ex fishermen
- v entrenched in simplistic management measures
- little requirement to consider other issues
2
Q
env act in 1995 changed SFCs…
A
- had to consider impacts to wider env in any decision making
- requirements of Council Directive 92/43/EC (Habitats Directive) became apparent with set up of Natura 2000 (N2K) network of sites
- Countryside & Rights of Way Act 2000 (CRoW)
- evidence appropriate management in place in designated sites, especially where specific permissions given
3
Q
Marine & Coastal Access Act 2009 – Sec. 153
A
- authority for an IFC district must manage the exploitation of sea fisheries resources in that district.
- In performing its duty under subsection (1), the authority for an IFC district must…
- seek to ensure that exploitation of sea fisheries resources is carried out in a sustainable way,
- seek to balance social & economic benefits of exploiting the sea fisheries resources of the district with the need to protect the marine env from, (or promote its recovery from), effects of such exploitation,
- take any other steps which in authority’s opinion are necessary / expedient for purpose of making a contribution to achievement of sustainable development, and
- seek to balance different needs of persons engaged in exploitation of sea fisheries resources in the district
4
Q
marine environmental surveys
A
- What is question that needs an answer?
- What info is required to be able to answer the question & how detailed does it need to be?
- What equipment is needed to gather the necessary information?
- What is the survey method?
- How will the data need to be presented?
5
Q
marine environmental survey considerations
A
- What sampling units are needed?
- What replication is required?
- Spatial scale?
- Representivity?
- How to ensure bias is removed / limited?
- What level of positional accuracy is required?
- What time is available is carry out the data collection and analysis?
6
Q
Marine environmental survey - techniques
A
Broadscale techniques:
- Single beam echo sounder – basic bathymetry
- Multibeam Echosounder (MBES) – detailed bathymetry
- Sidescan sonar – seabed texture and substrate differentiation
Remote imaging techniques:
- Drop frame camera
- Towed cameras
- ROV – remotely operated vehicle
- BRUV – baited remote underwear video
Direct techniques:
- Benthic grabs – Van Veen, Day, Hamon, Shipek
- Diver
- Dredges
- Trawls
- Traps
- Nets
7
Q
Whitsand and Looe Bay MCZ
A
- 1 of 4 priority sites
- initial proposal for total prohibition of bottom towed gear - against officer advice
- sidescan sonar used to image seabed
- 4 survey lines
- survey verified reef location (potential PSF & A. dohrnii habitat)
- Whitsand & Looe Bay Marine Conservation Zone (Fishing Restrictions) Byelaw 2018 came into effect Feb 2019
8
Q
DDV Work: Eddystone Project
DDV = drop down video
A
- Only SAC (special areas conservation) with zoned access to BTG (bottom towed gear)
-
Collaborative 6 year project with
MCS & University of Exeter - Currently funded by Princess Yachts
International - Sampling using DDV across 3 survey
boxes; 1 treatment & 2 control
boxes - Continuing to collect data beyond
the project
9
Q
Assessing new fishery activity
A
- Wrasse (type of fish)
- initial project in 2016
- fishery dependant catch sampling
- independent work (e.g. mark & recapture studies)
- byelaw
- analysing statistical returns
10
Q
IFCA
A
Inshore Fisheries and Conservation Authority
11
Q
how can we mop and map benthic (seabed) habitats, sp, and communities ?
A
achieved using range of technologies that operate at different spatial scales and resolutions
12
Q
Underwater Visual Census (UVC)
A
quantitative surveys based on direct diver
observations of marine species % habitats
13
Q
adv of UVCs
A
- can generate fine-scale data on abundance & diversity of marine species / habitats
- low-tech & can be implemented with minimal equipment & training (suitable for citizen science)
14
Q
What things do we need to consider & record to generate usable & reliable abundance & diversity data from a UVC?
A
-
standardised effort
-> UVC surveys generally involve swimming a transect of fixed, known length & counting numbers of individuals of diff sp observed in a “belt” of fixed width centred on transect -
observer error
-> individ surveyors vary in skill at identifying sp & in abundance estimates, which needs to be recorded, measured, or standardised (e.g. same surveyors, paired / ‘buddy’ transects) -
detectability
-> not all sp are equally detectable (camouflage, crypsis, diver avoidance)
-> often separate transects for mid-water & cryptic/benthic sp & invertebrates to account for variation in detectability
-> env conditions (e.g. turbidity, sea state) can also affect detectability and need to be recorded (UVC not possible in
some env) -
habitat
-> quadrat surveys often carried out in parallel with UVC to quantify sessile benthic fauna & flora (e.g. corals, seagrass) & habitat type (e.g. substrate, rugosity).
15
Q
photo quadrats
A
- method involves placing a fixed area quadrat on randomly / systematically selected locations on seabed …
- & photographing them at high resolution
- creates permanent visual record for later (re)analysis
