Hand digging
Methods
Lugworms (Arenicola spp.)
and rag worms (Nereis and Nephtys
spp.) are traditionally collected by using a fork
(occasionally spade) to hand dig over the lower
shore of a beach where dense worm beds are present.
Each spit of sand is turned over and quickly searched
for worms. Where bait species are more sparsely
distributed, a more productive method of collection
is to search for the signs of burrows of individual
animals (i.e. the largest king ragworms Nereis
virens) or investigate several areas by digging
small holes in order to find a site with a population
worth exploiting. Other large burrowing species
(razor shells Ensis spp. and other bivalves)
are dug in much the same way, usually after finding
signs of their siphons. Black lugworms Arenicola
defodiens are dug individually, sometimes using
a specially adapted spade, to extract them from
about an arms length depth, but most are now
taken by bait pump (see separate section, below).
Slightly different methods may
be used by different groups of bait collectors:
Professional and experienced local
bait diggers work methodically over a large area
of sand (Blake (1979) estimated 200 m2
per tide) by digging a series of adjacent trenches,
which are back-filled as they proceed, and take
only large worms. This is an economic method of
working, minimising the disturbance to the intertidal
habitat, and hence recovery of the infaunal community.
The method is very efficient and removes the majority
of worms in the area dug. Experienced and professional
bait diggers tend to manage their activities and
local bait populations. They will generally take
into account the cost-effectiveness of their efforts
and not over-exploit a worm bed when yields begin
to fall, provided that alternative sources are available
locally.
Less experienced or well-informed
bait diggers, usually occasional anglers collecting
for their personal use (apparently the majority
seen on most beaches) dig numerous scattered holes,
which are not back-filled but left open adjacent
to the mounds of spoil removed from the trench.
Although these bait diggers are less efficient at
finding and removing lugworms than professional
and experienced bait collectors, they often do not
limit the size or number of worms they take and
may sometimes exploit nursery areas. Many appear
to be prepared to continue bait digging for as long
as there are any worms available, regardless of
yield per effort. This activity may cause long-term
damage to bait stocks and intertidal habitats at
some locations.
Collection by more mobile groups
of commercial bait diggers is increasingly a source
of conflict in many areas. The increasing value
of and demand for bait, particularly in the autumn
and winter months, has encouraged the formation
of informal groups of commercial bait diggers who
may travel very long distances to bait beds. Bait
supply companies put together teams of bait diggers
and provide their transport to new areas of shore,
both locally and much further afield. One team of
commercial bait diggers reportedly travelled from
north-east England to south-west Scotland to dig
bait for the winter market (Fowler 1992), and teams
of bait diggers from Newcastle have been reported
to be digging bait in Scotland during winter 1998/99
(D. Donnan pers. comm.)
Commercial bait digging gangs reportedly
dig out bait populations over a period of a few
days (e.g. as reported by Arnold and Arnold 1985
and 1987), and sell the worms for resale in commercial
outlets, frequently a long distance away. These
bait diggers do not have the same incentive to conserve
the local bait resource, and may run into conflict
with local anglers who take bait for their personal
use, or indeed with local commercial bait diggers,
over resource use. Additionally, they may not be
sufficiently experienced or concerned with local
habitat conservation to backfill holes and minimise
damage to the habitat and shoreline species.
The increase in commercial baitdigging
has resulted in conflict between competing teams
of bait diggers and between local anglers and commercial
bait diggers. There is some anecdotal evidence to
suggest that the increase in bait digging pressures
by anglers and new suppliers for the retail bait
market, combined with declining local bait resources,
have driven some of the traditional bait diggers
out of business by over-exploiting their home areas.
Impacts on target species
Impacts on habitat
Impacts on non-target species
Impacts on other shore users
Opportunities for mitigation
References
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