West Sutherland Elver Survey

INTRODUCTION
West Sutherland Elver Survey 2008
ELVER DEFINITION
An elver is a 1 year old European eel (Anguilla anguilla) approximately 70mm long, light
brown to dark brown in colour, with no patterning. Elvers are found among mid shore
seaweed anywhere along the coast throughout the year but particularly in estuaries before
migrating into river systems during early summer in Sutherland. Elvers are most notable on
the edges of rivers close to the surface and on damp stones, culverts and walls of weirs
during migration. The term recruitment refers to elvers migrating in to freshwater and
joining the freshwater eel stock.
LOCAL CONCERNS OVER ELVERS
In 2006 the Sutherland Local Biodiversity Action Plan identified local concerns over decline
in elver migrations. This concern arose from three factors:
1. Identified decline of elvers across Europe
2. Lack of local information on the health or elver/eel stocks
3. Presence of elver fishing in Sutherland
Since 1999 European researchers have insisted that “European eel (A. anguilla) stocks are
outside safe biological limits”, with a drop of 99% in stocks since the 1980’s, while Japanese
eel (A. japonica) dropped by 99% since the early 1970’s and the North-American eel (A.
rostrata) suffering steep drop-offs as well (ICES 2002 & 2006). By the mid-1990s, the low
recruitment had lasted for a period equivalent to the average life-span of a mature eel in
the northern part of its range, and there was widespread concern in Europe that the stocks
could be on the verge of collapse (Potter & Dare 2003). After research in individual EC
countries and joint research programs, eels have been unanimously identified as in serious
decline. This caused the EC parliament to make legislation and insist on Eel Management
Plans (EMPs) to be established by 2009.
The decline of the European eel is often attributed to over fishing, with a drop of Elver
catches in England and Wales to 1% over the last 20 years and European Silver eel fishing
allowing less than 3% of the stock to return to the sea each year. There is good evidence
from a number of major elver fisheries throughout Europe of a long-term decline in elver
recruitment and in 1998 elver catches in Europe were reported to be down by 60 per cent
on the previous year and to be the lowest ever recorded (MAFF 2000). The Environment
Agency (EA) acted on this concern by putting together a National Eel Management Strategy
for England in 2001 and now regulates the fishing for eels in England.
Eels are the fastest declining UK vertebrate and are listed as a Priority Species in the
recently revised UK Biodiversity Action Plan (UKBAP) and Scottish Biodiversity Action Plan
(SBAP), identifying eels to be in ‘significant decline’ with ‘>25 % reduction of numbers’. Eels
were also added to the Scottish Executive’s ‘Scottish Biodiversity Strategy’ list in 2004. Even
the Royal Society of Edinburgh (Rands, 2000) noted that, "In particular, knowledge of eel
stocks is very limited, and management of eel fisheries in areas such as Wester Ross is
completely unregulated and the current situation can only be detrimental to what are
5 West Sutherland Fisheries Trust