Transcript Indicang presentation

INDICANG - UK
UK PARTNER - Westcountry Rivers Trust
UK Project Manager - Dr Polly Bown
Geographical location
Camel Catchment
Camel
Catchment
We are going to look at the Tamar and Camel
catchments, both in the Southwest of England
Geographical location
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In addition to
investigations on the
rivers Camel and
Tamar, we have been
asked to help setup an
eel monitoring system,
by the Field Studies
Council, looking at
Slapton Ley and its
associated tributaries.
River Camel
Slapton Ley
Physical Characteristics
CAMEL
 A 413km2 catchment that is approximately 40km long
 A major tributary of the Camel is the Allen
 The catchment is made of sandstone, slate and granite
 Historic mining and quarrying within the catchment
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The Camel Valley is a Site of
Special Scientific Interest (SSSI)
and a candidate Special Area of
Conservation (cSAC).
93% of the Camel catchment is
agricultural land
Physical Characteristics
TAMAR
 975km2 catchment with 18-35km long tributaries
 Tributaries include the Ottery, Inny and Lyd
 Most of the catchment is made up of sandstone and
shale, known as the Culm Measures
 Copper and Zinc contamination through mining
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There are several Sites of
Special Scientific Interest
(SSSI) in the Tamar
catchment
Physical Characteristics
SLAPTON LEY
 Slapton Ley is the largest freshwater lake in South West
England
 It is recognised as a National Nature Reserve (NNR)
wetland
 The Ley was created geomorphologically by the natural
damming of an estuary by a shingle bar, now known as
Slapton Sands
Environmental Constraints
AFFECTING UK EEL POPULATIONS
& WORK WITHIN INDICANG
Habitat Loss*  Wetland loss. There are no data available for
the Rivers Camel, Tamar and Slapton Ley,
however this could be mapped through
Indicang from past and present aerial photos.
 Eel migration barriers (dams, weirs and
dykes). None of the rivers have been mapped
for eel migration barriers, but they could be
mapped through Indicang. There are no large
barriers, such as hydro-electric power stations.
Camel Catchment
* Identified from Our Nation’s Fisheries Report. Environment Agency
Environmental Constraints
AFFECTING UK EEL POPULATIONS
& WORK WITHIN INDICANG
Pollution*  Siltation and nutrient pollution. Water quality data is available
from the Environment Agency but has never been mapped in
relation to sites where eels have been found. This work could
be completed through Indicang
 Effects of bioaccumulation on Eel reproduction
Camel Catchment
*Identified from Our Nation’s Fisheries Report.
Environment Agency
Environmental Constraints
OTHER CONSTRAINTS ON UK EELS
Parasites*  Impact of Anguillicola crassus on Eel populations (no data for
the Tamar, Camel or Slapton Ley)
Oceanic Climate change*  Possible effect of Atlantic Oscillation
Predation*  Cormorants taking Eels
Camel Catchment
*Identified from Our Nation’s Fisheries Report. Environment Agency
Eel Exploitation
FISHING EXPLOITATION & WORK WITHIN INDICANG
Tamar - There are a few registered official eel fishermen on the
Tamar who use Fyke nets for yellow and silver eels. We are trying to
find out if there are official records of these catches and if there are
any available data on sport fishing.
Camel - No registered eel fishermen.
Slapton Ley - Historical fishermen and a licence in place for renewed
Fyke netting for yellow and silver eels. We are hoping to gather data by
contacting fishermen.
Eel Status
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Past data on yellow eels have been obtained on the Camel and Tamar
by the Environment Agency, but only through bi-catches during
electro fishing for Salmonids. Past information for the Tamar and
Camel is currently being collected through Indicang and will be added
to current data. Past data is also being collected for Slapton Ley but
there is no current data. Through Indicang we hope to extend
monitoring to eel specific sites to gain more data on yellow eels.
There are no data on elvers and silver eels. We hope to improve this
knowledge through Indicang by setting up monitoring.
In the UK as a whole no river has data from all life history stages.
After Indicang we hope to have data for all three (elver, yellow and
silver) on the Tamar, Camel and Slapton Ley.
Little data means it is hard to know if areas within catchments have
altered in eel density. Data from UK index rivers suggest that eels
have declined to 1% of historic levels*.
* ICES (2002). Report of the ICES/EIFAC Working Party on Eels, Nantes France 2 - 6
September 2002 International Council for the Exploitation of the Sea, Copenhagen, Demark. 87pp.
Biological Studies on Eels within the UK
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Electro fishing for Salmonids have previously been
conducted in a number of rivers, with eels noted as a
bi-catch (Environment Agency).
Catch returns from UK commercial elver fisheries have
been noted for the river Severn and Bristol Channel
(which drain into the same area as the Camel river).
Data is currently being gathered for eels on many UK
rivers by Bark, Williams and Knights at Kings College
London and Westminster University.
The work through Indicang will supplement the current
eel research.
Possible Environment Constraints
that may affect eel populations
WITHIN THE CAMEL ,TAMAR AND SLAPTON LEY CATCHMENTS:
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Habitat Loss - There is no research on mapping wetland loss in the
catchments
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Migration Barriers - These have not been mapped with respect to
eels
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Water Quality - Although this data has been collected it has not
been mapped with respect to eels
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Eel Fishing - It is unlikely to be a constraint on the Tamar and
Camel due to low levels. It was thought to impact on eel populations
in Slapton in the past, but there is no supporting data
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Parasites - No data on parasites within these catchments
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Predation - No data
Summary of the UK Indicang
project
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There has been little monitoring of the Eel populations
within the Tamar, Camel and Slapton catchments and eels
have only been caught as a bi-catch. Extend eel specific
monitoring of elvers, silvers and yellows in all three river
catchments, where possible.
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Although attention to Salmonid barriers has occurred Eel
migration barriers have not been mapped. Therefore, eel
migration barriers will be mapped in all three rivers, where
possible.
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Wetland loss within the catchments has not been mapped.
Where possible current and past wetlands will be mapped
for all catchments from aerial photographs.
Summary of the UK Indicang
project
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Water quality has been recorded but not analysed in relation
to Eel populations. Therefore, past and present water quality
data will be gathered and mapped for all rivers, where
possible.
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Contact current and past eel fishermen in order to gather
data on catches.
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Present findings and organise meetings with river managers,
eel fishermen and the general public to disseminate the work
of Indicang.
INDICANG - UK
UK PARTNER - Westcountry Rivers Trust
UK Project Manager - Dr Polly Bown