Literature Review – summaries and synopses

Brief synopses of relevant sections of many published and unpublished papers concerning shoreline species collection are given below. The author has obtained not all those listed; some are difficult to source, and others were only identified at the end of the contract because they are referred to in the recent study of Quigley and Frid (1998). The section is intended to provide a more detailed guide to the literature than can be provided by a simple list of citations.

Reference Summary of relevant contents
Addessi, L. 1994. Human disturbance and long term changes on a rocky intertidal community. Ecological Applications 4(4): 786-797. Found a significant positive correlation between the number of inverted rocks and human activity on a shore. Density of all species was reduced in the most heavily visited areas.
Anderson, F.E. & McLusky, D.S. 1981. Physical recovery of an intertidal area disturbed by baitworm harvesting. Report to Natural Environment Research Council. Ref GR 3/4061, p. 1-52. One of two studies on recovery of sediments after bait digging in the Firth of Forth (also see McLusky et al. 1983). Examined recovery of areas where bait digging had been simulated, comparing ‘spoil and trench’ digging with infilling. A series of holes were dug, and microtopography, sediments in suspension and surface sediments were monitored for 30 days.
Anderson, F.E. & Meyer, L.M. 1986. The interaction of tidal currents on a disturbed intertidal bottom with a resulting change in particulate matter quantity, texture and food quality. Estuarine, Coastal and Shelf Science, 22, 19-29. Studied surface and suspended sediments after clam digging in Maine, USA.
Anon. 1995 (or 1996?) Angling in the Medina Estuary. Topic report by the Isle of Wight Division of the National Federation of Sea Anglers. Compiled in response to a request for information by the Centre for Coastal Zone Management, Portsmouth University. Describes nature and location of angling and bait digging activity and a survey of the Medina shore. Comments on CZM options. Prefers voluntary management options and notes that promotion of the NFSA Code of Practice needs most attention (only 1,200 of 5,000 anglers on the Island are NFSA members).
Arnold, J.B. and Arnold, W.B. 1985. Bait digging on the northern shore of Poole Harbour: April - November 1985: A preliminary study of six sites. Unpublished report to NCC, Dorset. General account of broad impacts of activity in Poole Harbour. The authors refer to bait beds being completely dug out by itinerant groups of commercial baitdiggers from outside the area.
Arnold, J.B. and Arnold, W.B. 1987. Bait digging on the northern shore of Poole Harbour: April - October 1986. Follow-up studies of six sites. Unpublished report to NCC, Dorset. Follow up of above.
Babbs, S. and Ravencroft, N. 1998. Bait digging on the Stour and Orwell Estuaries. Report to English Nature NB/T/404/97-98. Numbers and impacts of bait diggers assessed over autumn and winter of 97/98 through counts, questionnaires, circulars and literature searches. Overall the estuaries were not dug heavily, but obvious signs of digging impacts were visible in the most heavily used areas. Physical impacts of digging and potential effects of invertebrate populations were main management issues. Need for management was assessed. Considered first option should be for baitdiggers to set up their own means of policing a voluntary code of conduct, but if no progress is made control is recommended. Options include permits and wardening at key points. Total ban not considered acceptable or necessary. A Working Group is to be set up to consider the report.
Bass, N.R. 1970. Aspects of the ecology, behaviour and life history of the polychaete Nereis virens. Unpublished PhD Thesis. University of London. Not reviewed.
Bass, N.R. and Brafield, A.E. 1972. The life-cycle of the polychaete Nereis virens. J. Marine Biol. Ass. 52: 701-726. Not reviewed.
Bell, D.V., Odin, N., Austin, A., Hayhow, S., Jones, A., Strong, A., and Torres, E. 1984. The impact of anglers on wildlife and site amenity. Department of Applied Biology, UWIST, Cardiff. Examined impact of boulder turning for peeler crabs. Up to 90% of all boulders in a shore transect at Mumbles Head, Swansea, could be turned within a two week period and some boulders may be turned 40-60 times during the summer. Most boulders (60%) are not replaced in their original position. Larger boulders which are upended and not overturned completely are more likely to be left as they were found.
Beukema, J.J. 1995. The long-term effects of mechanical harvesting of lugworms on the zoo-benthos community of a tidal flat in the Wadden Sea. Netherlands Journal of Sea Research. 33(2): 219-227. Reports on a long-term study of a 1 km2 area. A near doubling of annual lugworm mortality rate resulted in a gradual and substantial decline of local lugworm stock from more than twice the overall mean at the start of the four year digging period. Total zoobenthos biomass fell even more because the population of the large bivalve Mya arenaria that initially comprised half of the total initial biomass was almost completely removed. Heteromastus filiformis was the only shortlived species to show a clear population reduction during dredging. Recovery of the benthos took several years, mainly because of the slow re-establishment of a Mya population with a normal size and age structure.
Beukema, J.J. and Vlas, J. de 1979. Population parameters of the lugworm Arenicola marina on the tidal flats in the dutch Wadden Sea. Netherlands Journal of Sea Research, 13, 331-354. Not reviewed.
Bishop, G.M., Holme, N.A., and Harvey, R. 1980. Survey of the littoral zone of the coast of Great Britain. Final report. Part I. The Sediment Shores. Part II. The Rocky Shores. An assessment of their conservation value. Marine Biological Association and Scottish Marine Biological Association. Report to NCC. Remarks on strong evidence of a marked deterioration in the richness of some shores since the late 19th century, particularly of marine algae at classical sites in the Southwest, heavily used by classes, and of some invertebrates collected for food, bait, or ornaments.
Blake, R.W. 1977. The exploitation of Nereis virens and Arenicola marina on the northeast coast of England. Unpublished PhD Thesis. University of Newcastle-upon-Tyne. See two publications below.
Blake, R.W. 1979 a. Exploitation of a natural population of Arenicola marina (L.) from the north-east coast of England. Journal of Applied Ecology, 16, 663-670. Bait diggers usually removed only about 70% of the worms present. Studies of the recovery of lugworm beds experimentally dug out at Whitley Bay indicated that complete recolonisation occurred after one month.
Blake, R.W. 1979 b. On the exploitation of a natural population of Nereis virens Sars from the north-east coast of England. Estuarine and Coastal Marine Science, 8, 141-148. Studied exploited and unexploited populations of king ragworms for one year on the north-east coast of England. Population densities were not significantly different, at about 15/m2 in summer and 3/m2 in winter, indicating that the dug population (most heavily exploited in summer) was probably not threatened by bait digging.
Brafield, A.E. and Chapman, G. 1967. Gametogenesis and breeding in a natural population of Nereis virens. JMBA UK 47, 619-627. Not reviewed.
Broad, G. 1997. An investigation of the ecological effects of harvesting cockles (Cerastoderma edule L.) by hand raking on the intertidal benthic communities in the River Dee estuary, North Wales. MSc thesis, School of Ocean Sciences, University of Wales, Bangor. Studied the effects of disturbing the ecological balance of intertidal communities through the hand raking of cockles. Signs of recovery wer seen after 2.5 months in small treatment plots, but not large ones. Observed changes in community structure were probably due to release of sulphides, destruction of diatom/bacterial layer, tubes and burrows within and on the sediment surface, and interference with normal predator/prey relationships. Time to recovery was similar to that found for mechanical harvesting impact, but considered to be less destructive to bait digging, particularly to the resident cockle population.
Brosnan, D.M. and Crumrine, L.L. 1994. Effects of human trampling on marine rocky shore communities. J.Exp.Mar.Biol.Ecol. 177: 79-97. Describes an experimental trampling regime. Upper shore trampling resulted in a significant decline in foliose algal species and the crushing and removal of barnacles. Patches caused by trampling in mussel beds continued to enlarge after trampling ceased and had still not recovered two years later. Overall, community structure shifted towards domination by algal turf species with fewer mussels.
Brown, B. and Wilson, H. Jr. 1997. The role of commercial digging of mudflats as an agent for change of infaunal intertidal populations. Journal of Experimental Marine Biology and Ecology. 218: 49-61. Not obtained.
Cadee, C.G. 1977. Het effect van pierenspitten op de worm Heteromastus. Waddenbulletin, 12, 312-313. Reports an 85% population decline of the polychaete Heteromastus filiformis, a common sediment shore invertebrate, after hand digging for lugworms.
Cadman, P.S. 1989. Environmental impact of lugworm digging. Report to the Nature Conservancy Council. Marine, Environmental and Evolutionary Research Group, University College of Swansea. CSD Report Number 910. One of several studies in South Wales of the impact of hand digging for worms on other populations of sediment shore habitats and common invertebrates and their recovery. Compared effects of trench digging with use of bait pumps on lugworm population recovery and effects on other spp. Not obtained for this study.
Cadman, P.S. and Nelson Smith, A. 1990. Genetic evidence for two species of lugworm Arenicola in South Wales. Marine Ecology Progress Series. 64, 107-112. Not reviewed.
Cadman, P.S. and Nelson Smith, A. 1993. A new species of lugworm Arenicola defodiens sp. nov. J.Mar.Biol.Ass.UK. 73(1) 213-224. Confirms that the ‘blacklug’ described by anglers is a new species. Appears to prefer the bottom of more exposed sandy shores.
Cadman, P.S. Studies on lugworm Arenicola. MSc Thesis. Not reviewed.
Caron, C., Boucher, L., Desrosiers, G., & Retiére, C. 1995. Population dynamics of the polychaete Nephtys caeca in an intertidal estuarine environment (Quebec, Canada). WHAT JOURNAL? 75, 871-884. Refers to the longevity of the species – one individual of 15 years old sampled.

Reference obtained from internet – journal still to be identified.

Castilla, J.C. and Duran, L.R. 1985. Human exclusion from the rocky intertidal zone of central Chile: the effects on Concholepas concholepas (Gastropoda). Oikos 45: 391-399. Comparison of open and restricted access shores indicates that a increase in numbers of the loco Concholepas concholepas (a carnivorous gastropod) as a result of a harvesting ban resulted in a decrease in a competitively dominant intertidal mussel which suffered from increased predation pressure from the gastropod. The bare space produced was subsequently colonised by other invertebrates and algae.
Cayford, J. 1993. Wader disturbance: a theoretical overview. In: Davidson, N. and Rothwell, P. Disturbance to waterfowl on estuaries. Wader Study Group Special Issue 68: 3-5. Reviews work on foraging efficiency, competition and dispersion, which may help to predict effects of disturbance (e.g. by bait collection) on wintering waders.
Chapman, G. and Newell, G.E. 1949. The distribution of lugworms (Arenicola marina) over the flats of Whitstable. Journal of the Marine Biological Association UK, 28, 627-635. Not reviewed. Inter alia, examined number and size of casts over a one year period from November 1946 to October 1947.
Chapman, M.G. and Underwood, A.J. 1996. Experiments on effects of sampling biota under intertidal and shallow subtidal boulders. Journal of Experimental Marine Biology and Ecology. 207: 213-237. Quoted in Quigley and Frid 1998. Not reviewed.
Chapman, M.G. and Underwood, A.J. 1997. Testing the effectiveness of intertidal protected areas in New South Wales. Final Report September 1997. Institute of Marine Ecology, University of Sydney, NSW, Australia. In 1993 NSW Fisheries gazetted a number of Intertidal Protected Areas around Sydney. These areas are theoretically closed to foraging and bait collection, although anglers may still fish in them. The project evaluated the effectiveness of IPAs three years after protection started. It found no changes in abundance or size-frequencies of populations of particular species, nor changes to the mid- and lowshore assemblages that could be attributed to protection of these populations in IPAs. Collection of animals collected in the two IPAs examined and public knowledge about IPAs did not improve during the study. Evidence was that the IPAs were ineffectively protected. Declaration of an IPA made no difference to the numbers of people foraging and taking bait, nor to the numbers who knew that this was no longer allowed. There was no public education apart from the few small signs in the IPAs. Provision of inspection or surveillance of IPAs by NSW Fisheries did not appear to be effective, possibly due to lack of resources. IPAs were not treated as protected areas by those who use the rocky shores as places to kill animals for bait and food.
Clark, R.B. 1977. Ecological impact of bait digging. Report on Pilot Study to the Nature Conservancy Council. CST Report Number 133. A desk study commissioned by the Department of the Environment after NERC (1973) noted a potential problem of stock depletion in some areas. It gave a preliminary assessment of the extent and nature of the ecological impact of bait digging by questionnaire survey, examined biological information, and made proposals for further work. Discusses problems of enforcement of regulation by various authorities.
Clark, R.B. 1980. Impact of bait digging on Cleethorpes beach. Cleethorpes Borough Council unpublished report. (Not seen, but presumably refers to the review commissioned by the Borough Council in connecting with the existing bye law restricting bait digging to only part of the beach for amenity reasons.)
Cleator, B. and Irvine, M. 1995. A review of legislation relating to the coastal and marine environment in Scotland. Scottish Natural Heritage Review No. 30. Summarises the legal and administrative mechanisms employed in the management of the coastal environment in Scotland and draws upon and updates the review of Legislative Responsibilities in the Marine Environment (NCC 1989). Approaches to coastal zone management in various other countries are reviewed and compared with the current situation in Scotland.
Coates, P.J. 1983. Fishing bait collection in the Menai Strait and its relevance to the potential establishment of a marine nature reserve, with observations on the biology of the main prey species, the ragworm Nereis virens. MSc report, Centre for Environmental Technology, Imperial College of Science and Technology, University of London. Studied the slow recovery of bait-dug areas in the Menai Straits. Describes unusual nature of king ragworm population there, a large proportion of which grows to an unusually large size before spawning (also see Olive 1987).
Creaser, E.P. and Clifford, D.A. 1982. Life history studies of the sandworm, Nereis virens Sars, in the Sheepscot Estuary, Maine, USA. Fisheries Bulletin 80, 735-743. The species has been of commercial importance in Maine for over 40 years. Study carried out in an area closed to commercial bait digging. Equal numbers of male and female spawners of <30 cm, but large numbers of females >30 cm were found. 30% of largest worms showed no signs of sexual development. Maturation of eggs could take from 12 to 18-20 months. Spawning occurred in April/May, four days after full moon during spring tides and during water temperature of 6-8oC. A 16 cm worm could lay 0.05 million eggs, and a 54 cm worm 1.3 million eggs. Male spawners emerged three hours after high tide.
Creaser, E.P. 1973. Reproduction of the bloodworm (Glycera dibrachiata) in the Sheepscot Estuary, Maine. J. Fish. Res. Board Can. 30: 161-166. Population of bloodworms is composed of five assumed year classes. Most spawners are probably large 3- and 4-year olds. Spawning takes place in June (water temperature over 13oC). Males emit streams of sperm while swimming at the surface, and females swim rapidly there, suddenly rupturing and releasing 1-10 million eggs.
Creaser, E.P. and Clifford, D.A. 1986. The size frequency and abundance of subtidal bloodworms (Glycera dibrachiata, Ehlers) in Montsweag Bay, Woolwich-Wiscasset, Maine. Estuaries. 9(3): 200-207. Bloodworms were first dug commercially from the area in 1933. Construction of a causeway in 1950 caused extensive areas of former beds to become subtidal. A 1971 study investigated whether the population continued to exist in the subtidal and might provide a source for juvenile recruitment into the heavily dug intertidal beds. The proposed removal of the causeway would result in the beds becoming available again for exploitation. The study estimated that some 6 million ± 3 million worms were present in the submerged area, worth $0.06-0.10 each in 1983.
Creaser, E.P., Clifford, D.A., Hogan, M.J. and Sampson, D.B. 1983. A commercial sampling program for sandworms, Nereis virens Sars, and bloodworms, Glycera dibranchiata Ehlers, harvested along the Maine coast. NOAA Technical Report NMFS SSRF-767. US Department of Commerce, National Oceanic and Atmospheric Administration, National Marine Fisheries Service. Covers possibly the best-documented and regulated fishery for bait worms in the world. Describes habitats, digging methods, packing media, and worm markets. Diggers are licensed by the State of Maine Department of Marine Resources. They take only one species or the other and sell their catch to licensed worm dealers, who pack and ship worms to wholesale distributors. Distributors sell to retail outlets, who divide shipments and sell worms by the dozen to recreational fishermen. The fishery was one of the top five commercial fisheries (landed value) in 1976, being worth over US $ 2 million.
Cryer, M. (ed). 1986. Angling and Wildlife. A report of the work undertaken for the MSC during the period May 1985 to May 1986. University of Wales, Institute of Science and Technology. One chapter studied effects of bait digging and overturning boulders for crab collection in South Wales (Swansea Bay, Barry Harbour and west Aberthaw). See published paper below.
Cryer, M., Whittle, G.N., & Williams, R. 1987. The impact of bait collection by anglers on marine intertidal invertebrates. Biological Conservation, 42, 83-93. Found no significant increase in the density of lugworms in depopulated areas during a six month experimental period. Controls and experimental sites converged in autumn and winter. (Initial densities at these sites were very low, at 9 and 16 worms/m2 and population growth usually occurs in spring and summer). Authors suggested that timing of collection may be important in determining impact. Recovery from summer and autumn digging is not likely to occur until larval settlement and juvenile and adult migration. Population likely to be protected against exploitation by low efficiency of removal and the large proportion located below low water on most beaches.

Boulders sheltering crabs on initial surveys (usually large, porous, irregularly shaped and heavily encrusted) were more likely to yield a crab on subsequent visits, whether or not replaced. When boulders with no crabs were replaced there was a significant increase in the probability of finding a crab under the same boulder on a subsequent visit. Replacing any boulder after searching for a crab significantly increased the probability of finding crabs on a subsequent tide.

Dales, P.R. 1950. The reproduction and larval development of Nereis diversicolor. J. Marine Biol. Ass. 29: 321-360. Not reviewed.
Davidson, N. and Rothwell, P. 1993. Disturbance to waterfowl on estuaries. Wader Study Group Special Issue 68: 3-5. Review of impacts of presence of individuals on the shore and other activities in estuaries on waterfowl numbers. Considers case studies from the Dutch Wadden Sea and Delta area, Denmark, Dee and Exe Estuaries, and a UK shooting disturbance project, and describes the effects of disturbance to waterfowl from bait digging and wildfowling in Lindisfarne NNR (see Townshend and O’Connor 1993, below).
Davis, S. 1993. Bait-digging on Gillan Creek. Report to Manaccan and St Anthony Parish Councils. Unpublished. Describes effects of increased commercial exploitation of bait beds in the Helford River, Cornwall, where habitat damage from bait digging is visible for several weeks after this activity. Investigates the issues surrounding the use of estuaries for bait digging and how the experiences of other areas may be used to safeguard the future of Gillan Creek and the Helford River. Various management options are suggested for discussion, including education, controls on access, licensing, and Local Nature Reserve designation.
De Potier, A. 1998. Environmental Research for Estuary Management: the Chichester Harbour Approach. Proceedings of a Seminar held on 27 April 1988. Chichester Harbour Conservancy. The Conservancy carried out an appraisal of the likely pressures in the Harbour in 1992 and invested in a wide-ranging programme of scientific research and monitoring to investigate natural processes and impacts and effects of human activity (including bait digging – see Farrell 1998). The Seminar disseminated the research results.
Dye, A.H. 1992. Experimental studies of succession and stability in rocky intertidal communities subject to artisanal shellfish gathering. Netherlands Journal of Sea Research 30: 209-217. Not reviewed. Cited in Quigley and Frid.

Notes that community level parameters such as species diversity or richness do not always result in a predictable fashion to the effects of human predation.

Dyrynda, P. 1995. Impacts of bait dragging on the seabed within Poole Harbour. Report to Southern Sea District Fisheries Committee from the Marine Environmental Research Group, University of Wales, Swansea. An unusually large population of Nereis virens occurs on muddy shores and shoals in the Harbour. Unregulated bait dragging by about 15 vessels occurs on very soft muddy ground that is unsuitable for bait digging. A double-tined fork is dragged through the sediment by a motor vessel, hooking and dragging out large worms. There is concern about the impact of this activity on seabed ecology and privately leased mariculture beds laid with mussels and other shellfish. The report describes results of experimental bait dragging on natural seabed and newly laid Mytilus edulis plots. Bait dragging has a smaller impact than bait digging, but is more widespread; carried out across many remote and otherwise undisturbed areas, as well as on the lower shore of beaches also dug by hand. In addition to the removal of large numbers of ragworms, other large infauna are likely to be damaged by dragging, which causes disturbance to a depth of 0.3-0.5 m. If undertaken in these habitats, it would also cause extensive damage to Zostera beds, Sabellaria (tubeworm) beds and saltmarsh. Mussel aggregations are displaced and disrupted, with some overturned and buried. No evidence of shell damage was recorded.
Dyrynda, P. and Lewis, K. 1994. Sedimentary shores within Poole Harbour: Bait harvesting and other human impacts. Report to English Nature (South-West Region) from the School of Biological Sciences, Swansea University. Field surveys undertaken at nine locations on the northern shore. Assessments covered habitats and invertebrate fauna, with particular reference to five bait species. Lugworm stocks are substantial, as are kingrag worms. Sustainable commercial yields of the latter appear to be maintained from baitdragging. Catworms (white rag Nephtys spp.) may be most vulnerable to overexploitation and there is some evidence for midshore depletion. Some large and fragile non-target infauna (e.g. acorn worm Saccoglossus horsti) are considered very vulnerable to baitdigging, as are seagrass Zostera and peacock worm Sabella pavonina beds when exposed during extreme spring tides. Different shore types recover at different rates, and heavily-dug stony beaches are most seriously affected. Recommendations are made for management and for further studies. Latter included study of impact of bait dragging (see above), impacts of kingrag Nereis virens and white rag Nephtys digging, and impacts of bait harvesting on bird and fish populations.
Dyrynda, P.E.J. and Brown, F. 1998. Factors affecting condition and mortality of farmed mussels in Poole Harbour: 195-1997. Final report to Southern Sea District Fisheries Committee from the Marine Environmental Research Group, University of Wales, Swansea. Bait collection not considered.
Emerson, C.W., Grant, J. and Rowell, T.W. 1990. Indirect effects of clam digging on the viability of soft-shelled clams Mya arenaria. Netherlands Journal of Sea Research. 27(1): 109-118. Used laboratory experiments to see whether non-lethal burial or exposure on the sediment surface could alter the normal living depth of M. arenaria in sand and mud. Clams buried more deeply than normal in sand had not recovered to normal depths after two weeks, and exposed clams on mud had reburrowed to abnormally shallow depths in two weeks. Concluded that the impacts of clam digging are not only removal of market-sized clams and shell breakage of remaining ones. Exposure of pre-recruits may increase susceptibility of unharvested clams to predation, desiccation or freezing, with effects depending on different sediment types.
Evans, J. and Clark, N.A. 1993. Disturbance studies on Swansea Bay and the Burry Inlet in relation to bird populations. BTO Research Report No. 107. Study carried out in February 1993. Lower numbers of bait diggers were seen than expected (possibly due to time of year). Because beaches between Marina and Mumbles are heavily disturbed they are not used by waders, and the Burry Inlet is an important feeding site. Large numbers of birds, particularly oystercatchers, feed and roost there. Disturbance to feeding and roosting birds (particularly oystercatchers and curlew) by cocklers accessing Llanrhidian Sands was recorded.
Evans, L.J. and Macpherson of Cluny J. 1993. Anderson v. Alnwick District Council. 1 Weekly Law Reports. 1993. Pp 1156-1171. Summarise judgements over the Budle Bay bait digging prosecution case history. Inter alia, confirmed that the foreshore extends to the limit of the low water line at any time; that there is a public right to take worms from the shore ancillary to the public right to fish in the sea, but this right is not unrestricted (collection for sale is not permitted) and may be regulated in certain areas provided that alternative sources of bait are available reasonably close by. See case study for more details.
Evans, S.M., Arnott, S. and Wahju, R.I. 1994. Evidence of change in the macrofauna of tidal flats subject to anthropomorphic impacts in north-east England. Aquatic Conservation: Marine and Freshwater Ecosystems. (4) 333-334. Study assessed differences that had occurred in macrofaunal assemblages of tidal flats between 1931 and 1991. Dominant members of assemblages were same for both surveys, and almost all taxa recorded in 1931 were present. Two sorts of change were evident: an Arenicola/Scoloplos/Cerastoderma/Macoma community had been replaced by an oligochaete-dominated community in part of Budle Bay, and numerical densities of macrofauna were higher in 1991, both probably the result of eutrophication. Baitdigging had been intense at one site since at least the early 1930s, but both target species (Arenicola and Nereis virens) still occurred there.
Farke, H., De Wilde, P.A.W.J. and Berghuis, E.M. 1979. Distribution of juvenile and adult Arenicola marina on a tidal mud flat and the importance of nearshore areas for recruitment. Netherlands Journal of Sea Research, 13 (3/4) 354-361. Not reviewed.
Farrell, P. 1998. Environmental impacts of baitdigging. In de Potiers, A. 1998. Environmental Research for Estuary Management: the Chichester Harbour Approach. Proceedings of a Seminar held on 27 April 1988. Chichester Harbour Conservancy. Three year research study carried out because of increased commercial bait digging for king ragworm in the Harbour. Results were needed to support possible introduction of a bylaw. An experimental site was established in a remote location and sediment invertebrates sampled before and after digging. Four species were significantly affected. A large worm Amphitrite johnstoni and its commensal Harmathoe imbricata were completely absent following digging, and still at very low numbers a year later. Cockle Cerastoderma edule numbers fell slightly after digging. Common periwinkle Littorina littorea numbers increased – they moved into the area and settled on large flints exposed by digging.
Farrell, P. 1996. The environmental impact of bait digging: effects on the infauna and epifauna of Chichester Harbour. Report for the Institute of Marine Sciences, Portsmouth. Some local concern about effects of bait digging in the harbour, but no local research had been carried out. This project studied local effects, including areas dug, commercial outlets in the region, and discussions with bait diggers. Nereis virens is the main target species.
Fitzpatrick, S., and Bouchez, B. 1998. Effects of recreational disturbance on the foraging behaviour of waders on a rocky beach. Bird Study. 45:157-171. Quoted in Quigley and Frid 1998. Not reviewed.
Flach, E.C. 1992. Disturbance of benthic infauna by sediment reworking activities of the lugworm Arenicola marina. Netherlands Journal of Sea Research 30, 81-89. Not reviewed.
Fletcher, H. 1997. The impact and management of visitor pressure on rocky shore communities. PhD Thesis. University of Newcastle upon Tyne. Quoted in Quigley and Frid 1998. Not reviewed.
Fletcher, H. and Frid, C.L.J. 1996. Impact and management of visitor pressure on rocky intertidal algal communities. Aquatic Conservation: Marine and Freshwater Ecosystems. 6: 287-297. A trampling study at two sites in Northeast England resulted in reduced abundance of fucoid and turf algal species and increased amounts of bare space in trampled plots. Suggested that changes to algal composition may result from as few as five people walking over the area on each spring tide cycle.
Forbes, A.J. 1984. The bait worm fishery in Moreton Bay, Queensland. Queensland Department of Primary Industries, Project Report Q 084009, pp. 18. Not obtained.
Fowler, S.L. 1992. Survey of bait collection in Britain. Joint Nature Conservation Committee Report No. 107. A review of species, community and habitat effects updated by this report. Also describes result of a bait collection survey circulated in 1985 to local authorities (County Councils, District Councils and some Harbour or Ports Authorities), angling clubs, conservation organisations and interested individuals.
 

Gee, K. 1993. Impact of recreation on the intertidal habitats of the Menai Strait proposed marine nature reserve: an assessment of sustainability. MSc University College London.

Sea angling and bait digging were the recreational activities found to have the greatest impact on intertidal communities. The latter has a widespread impact on the soft shores, particularly ragworm beds, and causes not only a decline in the ragworm population but also associated infauna. It is ultimately considered to be unsustainable in the long term because conditions do not allow quick repopulation of depleted areas.
Ghazanshahi, J., Huchel, T.D. and Devinny, J.S. 1983. Alteration of Southern California Rocky Shore Ecosystems by Public Recreational Use. Journal of Environmental Management (16) 379-394. Describes how visitors can damage rocky shore ecosystems by taking organisms and trampling them underfoot. Usually only a few prominent animals are removed, and populations (including rarities) may increase because of reduced competition by former dominants. Trampling reduces algal populations, with abundant species most heavily affected.
Girvan, J. 1995. Judgement 1995 No. 1114 in the High Court of Justice in Northern Ireland Chancery Division between Thomas Adair (plaintiff) and the National Trust and the Crown Estate Commissioners (Defendants). Confirmed the right of the plaintiff and others to collect winkles and whelks from the waters, bed and foreshore of Strangford Lough, and the right to collect worms related to an actual or intended right to fish, but not for commercial resale. More details in Strangford Lough case study.
Godden, N.R.S. 1995. Crab trapping in the South Devon Estuaries (primarily around Plymouth). Honours Project submitted in partial fulfilment of the requirements for the degree of BSc. Plymouth University Institute of Marine Studies. Investigates the trapping of crabs using guttering and tiles in the south Devon estuaries, primarily around Plymouth. Numbers have grown from none to 8,750 traps at Plymouth, and increased 10-fold in the Exe and Teign estuaries. Commercial collectors supply local angling shops and outlets elsewhere. Natural crab populations fluctuate yearly, seasonally and daily, and larval planktonic stages allow recolonisation of depleted areas. Extent of depletion is therefore hard to prove. Increased fishing effort also provides sanctuaries for marine animals and plants at low tide, and sources of food for fish and birds.
Goss-Custard, J.D. and Verboven, N. 1993. Disturbance and feeding shorebirds on the Exe Estuary. Wader Study Group Bulletin. 68: 59-66. Not obtained.
Grant, J. 1981. Sediment transport and disturbance on an intertidal sandflat: infaunal distribution and recolonization. Marine Ecology - Progress Series, 6, 249-255. Not reviewed.
Hall, S.J. and Harding, M.J.C. 1998. The effects of mechanical harvesting of cockles on non-target benthic infauna. Scottish Natural Heritage Research, Survey and Monitoring Report No. 86. Describes result of three year study in Auchencairn Bay, Solway Firth. Preliminary survey was followed by two manipulative field experiments on suction dredging and tractor dredging. Suction dredging effects were statistically significant, but recovery had occurred by 56 days after dredging. The effects of tractor dredging were not statistically significant, but this was likely because the experiment was carried out at a different time of year. Concluded not possible to make a distinction between the effects of the two methods, recovery from both is rapid, and overall effects on populations low.
Havard, M.S.C. and Tindal, E.C. 1991. The impacts of bait digging on the polychaete fauna of the Swale Estuary, Kent, UK. Polychaete Research 16, 32-36. The impact of bait digging was investigated by measuring digging activity and species affected. It was estimated that 6.5% of Arenicola marina (main target species) were removed annually (4,300 worms per day or over 1.5 million per year – probably an underestimate). Recovery was measured in experimental dug plots. After digging there was an immediate loss of invertebrates, both the target bait species and other species disturbed in the digging process. Dug areas were recolonised over a period of some months. After six months (January to July) A. marina in the experimental dug plots had only recovered to 21% of control site numbers. Other species, e.g. Scoloplos armiger, returned to 78% of original levels within the period. This level of exploitation gives rise to some concern as to the sustainability of the activity.

Bait diggers need a permit to dig in the Swale Local Nature Reserve. Only five of 841 bait diggers approached by wardens during a six week period in 1984 had valid licenses. The majority claimed ignorance of the designated conservation area and the need for a license.

Heiligenberg, T. van den. 1987. Effects of mechanical and manual harvesting of lugworms Arenicola marina L. on the benthic fauna of tidal flats in the Dutch Wadden Sea. Biological Conservation, 39, 165-177. Studied effects of both hand and mechanical digging on habitats, lugworm populations and other sediment infauna. Monitoring of the fauna of dredged sites was carried out for six months. (The rate of physical recovery of the sediment surface is not recorded.)

Hand digging caused a significant reduction in many of the common species, including Scoloplos armiger, Nereis diversicolor, Heteromastus and, of course, Arenicola (50% removal). A total of 1.9 g of other benthic animals were removed for every 1 g of Arenicola. Mechanical digging has a much more serious effect, with complete removal of Arenicola and up to an 80 or 90% loss of the Baltic tellin Macoma baltica, Scoloplos and Heteromastus. Using this method, for every gram of lugworm taken, 9 to 13.4g of other invertebrates are removed from the area. Dredges strain sediment through a sieve with water jets, leaving gullies 40cm deep and one metre wide, bordered on each side by a 1.5 metre wide ridge a few cm high. They usually only operate within a very large area of intertidal sand flat, and are likely to leave considerable areas untouched.

Herwerden, L. van. 1989. Collection of mussel worms Pseudonereis variegata for bait – a legislative anachronism. South African Journal of Marine Science, 8, 363-366. Not obtained.
Hockey, P.A.R. 1987. The influence of coastal utilisation by man on the presumed global extinction of the Canarian black oystercatcher Haematopus meadewaldoi Bannerman. Biol. Cons. 38, 49-62. Considers that one of the factors that could have contributed to the extinction of this species may have been intensive exploitation of intertidal organisms. The limpet Patella canedei is still locally extinct as a result of this activity.
Hockey, P.A.R. and Bosman, A.L. 1986. Man as an intertidal predator in Transkei: disturbance, community convergence, and management of a natural food resource. Oikos 46, 3-14. Proposed that human collecting activities on sessile filter feeders, grazing and predatory gastropods provided a form of non-selective intermediate disturbance that resulted in an increase in species diversity in harvested areas.
Howell, R. 1985. The effect of bait digging on the bioavailability of heavy metals from surficial intertidal marine sediments. Marine Pollution Bulletin, 16, 292-295. Records increased levels of heavy metals found in surface sediments and invertebrates following intensive bait digging in Budle Bay. Estimated that the weight of sediment turned over by 50 diggers was 62.5 tonnes. The exposure and subsequent oxidisation of deep sediments by digging enables heavy metals (cadmium and lead) which are bound to sediment particles in reduced (anoxic) conditions to become bioavailable. Cadmium is also concentrated in the anoxic layers by the activity of lugworms; their removal therefore exacerbates this problem.
Huggett, D. 1992. Foreshore fishing for shellfish and bait. RSPB. Considers cockle fishing and bait worm collection by hand and dredge. Summarises legal aspects of foreshore fisheries (ownership of foreshore, access etc.), life histories of target species, and impacts of bait digging by hand and by mechanical lugworm diggers.
Huggett, D. 1995a Coastal zone management and baitdigging: A review of potential conflicts with nature conservation interests, legal issues and some available regulatory mechanisms. In: Management techniques in the coastal zone. Proceedings of the Conference organised by the University of Portsmouth, October 24-25, 1994. Extremely useful review of the legal status, management and potential for regulation of bait digging.
Huggett, D. 1995b. A review of coastal zone management powers. A response to the Department of the Environment’s review of byelaw making powers in the coastal zone. Royal Society for the Protection of Birds, August 1995. The difficulty of achieving effective control of bait collection is one of the issues discussed in this document. Inter alia, it examines restrictions in byelaw purposes, constraints on the operation of voluntary agreements and causes of failure, legislative constraints, conflicts in duties, functions and powers, and the problem of public rights and third party activities. Several case studies are described.
Hunter, E. and Naylor, E. 1993. Intertidal migration by the shore crab Carcinus maenus. Marine Ecology Progress Series. 101: 131-138. Quoted in Quigley and Frid 1998. Not reviewed.

 

 

Jackson, M.J. & James, R. 1979. The influence of bait digging on cockle, Cerastoderma edule, populations in north Norfolk. Journal of Applied Ecology, 16, 671-679. Suggest that intensification of commercial digging for bait worms on the North Norfolk coast in the 1950s and '60s resulted in a decline in cockle Cerastoderma edule populations. Undisturbed cockle beds were not affected. Cockles were thought to be killed by burial by bait digging, because they cannot regain their normal position at the surface of the sediment if deeply buried in overturned spoil. Authors estimated that a bait digger turns over 6-12m-2 of sand in a tide, or 25-50 acres per year on the north Norfolk sands.
James, R. Perrow, M.R. and Thatcher, K. 1993. The effects of bait digging on the benthic fauna of intertidal flats. No publication information. Influence of bait digging on marine benthic invertebrates determined by field and laboratory experiments. Infauna sampled in experimentally dug plots and adjacent controls at two sites in eastern England from January to March 1990. Arenicola marina, Nephtys caeca, Lanice conchilega, Cerastoderma edule and Nematode densities were significantly reduced by digging; Macoma balthica, Ostracoda, Harpacticoida and Foraminifera densities were not. Laboratory experiments demonstrated the mobility and resistance of Macoma to burial, and vulnerability of Cerastoderma.
Johnson, G. 1984. Bait collection in a proposed marine nature reserve. MSc Report, Ecology and Conservation Unit, University College London. Continued study by Coates 1983. Describes methods of bait collection of peeler crab, lugworm and king ragworm, and distribution and numbers of bait collectors in the Menai Strait. Disturbance found to be widespread, but particularly intensive within the ragworm beds (where 30-50% of most popular areas were disturbed each year) and in virtually all suitable areas for moulting crab (where 70-90% of rocks showed signs of being displaced). Studied the recovery of bait dug areas in very sheltered conditions, where bait digging results in the movement of underlying boulder clay to the surface. Some experimental plots were still visible one year after having been dug, and all holes dug during the season were still present at the end of the season.
Johnston, J. 1991. Impact of bait digging on the wintering birds of Spurn Bight. English Nature Report. Compares trends in number of wintering birds in the study area, where bait digging is common, with national trends. Desk Study.
Jones, A. 1992. An assessment of the implications of bait digging for the nature conservation interests of the Welsh shore of the Severn Estuary/Bristol Estuary. CCW South Wales Report CCW/SW/12. Established extent of bait digging on the Welsh shore of the Severn Estuary through direct observations (at Burry Inlet, Sully Island and Cardiff foreshore), contacts with bait diggers, retail fishing outlets, and local organisations. Species collected included lugworm, king ragworm, razor shells and peeler crab. Sales of lugworm and ragworm in local shops varied from 1 to 100 lbs per week. All sources indicated that lugworm was in decline on the Welsh coast. Decline in birds using Swansea Bay attributed by observers to bait digging.
Kaiser, M.J. and Pickett, G. 1996. The effects of fishing on the marine environment. Intertidal fisheries paper for EN/MAFF workshop. Lists main effects as: 1) physical disturbance of the sediment, 2) direct removal or death of non-target organisms, 3) transport of contaminants and heavy metals at the sediment surface, 4) sediment resuspension, and 5) localised reduction in food for birds and other predators. Considered collection of lugworm, king ragworm and premoult green crabs. Reviews much of the same literature covered here.
Keough, M.J., Quinn, G.P., and King, A. 1993. Correlations between human collecting and intertidal mollusc populations on rocky shores. Conservation Biology 7(2): 378-390. Quoted in Quigley and Frid 1998. Not reviewed.
Kingsford, M.J., Underwood, A.J., and Kennelly, S.J. 1991. Humans as predators on rocky reefs in New South Wales, Australia. Marine Ecology Progress Series. 72: 1-14. Quoted in Quigley and Frid 1998. Not reviewed.
Langton, A. 1994. Report to the Secretary of State for the Environment on a Public Inquiry held at the Guildhall, Berwick-upon-Tweed, March 1994. Provides a useful background to the history of bait digging controls at Budle Bay, Lindisfarne National Nature Reserve (NNR), the approval of the Section 29 Order and amendment of the NNR byelaws prohibiting bait digging in the Bay. See case study for more details.
Latus, J.E. 1993. A study into the exploitation of Arenicola marina L. on the River Camel (North Cornwall). No publication details. Regional English Nature Report? Not obtained for review.
Liddiard, M., Gladwin, D.J., Wege, D.C. and Nelson-Smith, A. 1989. Impact of boulder-turning on sheltered sea shores. Report to the Nature Conservancy Council. School of Biological Sciences, University College of Swansea. NCC CSD Report 919. Authors suggest that a minimum of 3,000 rocks were overturned daily during periods of reasonably low tides at both Mumbles and Oxwich. An unknown proportion involve the repeated overturning of the same rocks. No 'serious' collector was seen to replace rocks in their original position. The chief result of this damage to rocky shores is the loss of habitat stability, which in turn seriously affects the range of species found on and beneath boulders. The removal of large algae will also cause the destruction of their understory habitats, which are important for the shelter provided to small algae and invertebrates.
Litten, J.M. 1993. A study of Arenicola marina and the environmental impact from their exploitation as a sea angling bait. BA (Hons) study. Coleg Normal Bangor. Examined life-cycle of lugworm and environmental impacts of harvesting on their populations, habitat and non-target species by literature review and studies in Red Wharf Bay and Benllech Bay, Anglesey. Recovery of the sediment after digging on the high-energy beach of Benllech Bay was less than 7 days, but longer than this at Red Wharf Bay.
Lynch, P. and Prokop, F. 1993. Intertidal invertebrates – Regulations. NSW Fisheries Fishnote DF/28, July 1993. Introduced reduced bag limits for intertidal species collection, permitted harvesting methods, and declaration of protected areas where no harvesting may take place. Fines of up to $10,000 apply for breaching NSW Fisheries regulations.
McKay, D.W. and Fowler, S.L. 1997 a. Review of the exploitation of the mussel Mytilus edulis in Scotland. Scottish Natural Heritage Review. No. 68. Collection of mussels for food and bait has been undertaken in Scotland since prehistoric times. Catches have been recorded since 1886, and have declined significantly over the past 100 years. Mussels were collected by hand prior to 1986, and by mechanical dredging since 1986. In 1994 mussels were the seventh most important shellfish in terms of weight landed and 12th in terms of value. Most natural mussel beds yield mussels only suitable for processing. A questionnaire circulated to Scottish Natural Heritage and Scottish Fisheries Protection Agency Staff reported only a small amount of collection of mussels for personal use (table or fishing bait), and commercial collection. There is no right of public fishery for mussels in Scotland, but it is probably a tolerance. The environmental role of mussels in the natural environment is considered. They provide an important habitat for other invertebrates, and a food source for birds and feeding fish. Compared with commercial mussel collection, the impacts of hand collection are considered to be small, although unstudied in the UK.
McKay, D.W. and Fowler, S.L. 1997 b. Review of Winkle Littorina littorea harvesting in Scotland. Scottish Natural Heritage Review. No. 69. Collection of winkles for food has been undertaken in Scotland since prehistoric times. In 1994 winkles were the sixth most important shellfish in terms of weight landed and 7th in terms of value according to official landings statistics. This is almost certainly a considerable under-estimate – exports are probably twice this. Habitat damage (chiefly by stone turning and disturbance to algae) and habitat and community change (caused by removal of an important herbivore) is briefly reviewed, as are impacts on winkle populations and shore birds and mammals. Collection will cause depletion of winkle populations, but has little permanent effect because it targets the largest individuals that are frequently no longer contributing to recruitment due to infestation by parasitic flukes.
McLusky, D.S., Anderson, F.E. & Wolfe-Murphy, S. 1983. Distribution and population recovery of Arenicola marina and other benthic fauna after bait digging. Marine Ecology - Progress Series, 11, 173-179. The process of digging for bait causes the death of many other marine invertebrates, by physical damage, burial and smothering or exposure to desiccation and predation. Recovery of dug areas takes place most quickly (within three weeks) where holes and trenches are back filled (McLusky et al. 1983), and in the most wave-exposed areas. Rapid recolonisation by Arenicola is thought to occur by above surface migration in response to enhanced organic matter levels in the soft microhabitat of the trenches. Bait digging did not pose a significant threat to spawning stock of lugworms.
Mitchell, A. 1995. The effect of bait digging on the intertidal macrofauna of the Stour and Orwell estuaries. Suffolk Wildlife Trust. Compared densities, biomass and distribution of species in areas with and without digging.
Natural Environment Research Council. 1973. Marine wildlife conservation. NERC publications Series B, No. 5. NERC. Noted bait digging was a potential problem in some areas.
Nature Conservancy Council & Natural Environment Research Council. 1979. Nature conservation in the marine environment. Report of the NCC/NERC Joint Working Party on Marine Wildlife Conservation. NCC. Identified 'strong evidence of damage to sandy and muddy beaches by bait-digging.'

Reported that the National Anglers Council estimated in the 1970s that about 75% of anglers prefer to dig their own bait.

New South Wales Agriculture and Fisheries. 1991. Managing harvesting activities in intertidal habitats. A discussion paper. NSW Agriculture and Fisheries, Australia. Outlines the problem caused by increasing numbers of human foragers removing ‘all forms of life’ from intertidal areas. Bag limits introduced for some species in 1988 have been ineffective in controlling harvesting activities. Some harvesting methods cause significant habitat damage. Describes proposed management plan to totally protect selected sites from harvesting activities, which should then serve as a reservoir for repopulation elsewhere. Also tightly controls harvesting elsewhere by specifying permitted methods and imposing bag limits on many intertidal invertebrates. Proposes to develop an educational programme, improve effectiveness of enforcement, and monitor effectiveness.
Newell, G.E. 1948. A contribution to our knowledge of the life history of Arenicola marina L. J.Mar.Biol.Ass.UK. 27:554-580. Not reviewed.
Newell, G.E. 1949. The later larval life of Arenicola marina L. J.Mar.Biol.Ass.UK. 28: 635-639. Not reviewed.
Nicholson, D. 1979. Observations on the population structure and recruitment of the lugworm Arenicola marina, with particular reference to its exploitation as a bait species. Unpublished. Department of Zoology, University of Newcastle-upon-Tyne. Not reviewed.
Norris, K., Bannister, R.C.A., and Walker, P.W. 1998. Changes in the number of oystercatchers Haematopus ostralegus wintering in the Burry Inlet in relation to the biomass of cockles Cerastoderma edule and its commercial exploitation. Journal of Applied Ecology. 35: 75-85. Quoted in Quigley and Frid 1998. Not reviewed.
Olive, P. 1984. Survey of the littoral infauna at Newton-on-Sea. Report to the Nature Conservancy Council. CST Report no. 533. Describes unique scientific importance of the beach, which has a diverse fauna including several species that only occur at this locality in Northumberland and Durham. The same area has a population of large lugworms. Exploitation of these stocks would result in predation and accidental damage to the sediment structure and other associated species, including Echinocardium cordatum, and the unique interstitial fauna of the beach. Recommends that present policy restricting bait digging should continue.
Olive, P.J.W. 1985a. A Study of lugworm populations in the Lindisfarne National Nature Reserve. Final report to the Nature Conservancy Council. CST Report 569. Mainly summarised in Olive 1993. Describes two-year period when no bait digging took place in Budle Bay, followed by 6-month period of restricted bait digging. Study demonstrated that the site could not withstand the level of exploitation experienced in winter 1984/85.
Olive, P.J.W. 1985b. Slow grow white ragworm. The Sea Angling Handbook. Winter 85/86. 28-31. Popular article. Describes biology, age, and breeding strategy of Nephtys. These species are long-lived, slow-growing and offspring have a low survival rate to adulthood. Additionally, they do not breed every year. From 1975-1985 one of the common British species only bred successfully in two years. Also describes the much larger more ferocious US bloodworms Glycera, which inject their prey with poison.
Olive, P.J.W. 1985c. Ragtime. Article in: The Sea Angling Handbook. Autumn 1985. 21-23. Popular article. Describes biology and breeding cycle of Nereis species. Explains that bait beds are inadequate to meet demand, as a result of over-digging, pollution and land claim in estuaries.
Olive, P.J.W. 1986. Lugworm; abuse or management?. Article in: The Sea Angling Handbook. Autumn 1986. 61-63. Makes suggestions for rotational closure of bait beds to increase yields.
Olive, P.J.W. 1987. Menai Strait ragworm studies. A report to the Nature Conservancy Council. CSD Report No. 802. Describes unusual nature of king ragworm population in the Menai Strait. Despite rapid initial growth of young worms in the Strait, comparable to that achieved in the laboratory, there is an unusually long period of growth in most individuals before spawning occurs. Animals of two to three feet in length that show no signs of maturation have been recorded. Small individuals are very scarce. The maximum proportion of the population found to be spawning in one year was about 20%, much lower than normal. The study site was subject to intensive digging, resulting in serious and at least semi-permanent environmental damage from boulder displacement and exposure of underlying boulder clay. This would result in serious damage to the associated and important faunal communities present at these sites.
Olive, P.J.W. 199? Polychaeta as a world resource: patterns of exploitation, management and the potential for aquaculture based production. Memoires Museum d’Histoire Naturel, Paris. ???? Not obtained.
Olive, P.J.W. 1993. Management of the exploitation of the lugworm Arenicola marina and the ragworm Nereis virens (Polychaeta) in conservation areas. Aquatic Conservation 3, 1-24. Presents two case studies: Arenicola marina exploitation in the Lindisfarne National Nature Reserve, and Nereis virens in the Menai Strait. Neither are examples of a sustainable economic pattern, and could not support continuous production or export to significant markets. Management of the exploitation of bait populations in conservation areas is discussed in relation to world patterns of utilisation and supply.
Olive, P.J.W. and Cadman, P.S. 1990. Mass mortalities of the lugworm on the South Wales Coast: a consequence of algal bloom? Marine Pollution Bulletin 21(11):542-545. An algal bloom on the South Wales coast first affected the Burry Inlet in September 1990, and four weeks later Swansea Bay. This is thought to have led to a decline in the lugworm population.
Olive, P.J.W. and Cowin, P.D.B. 1994. The management of natural stocks and the commercial culture of polychaeta as solutions to the problems of bait digging and worm supply for sea angling in the UK. Polychaete Research 16: 23-27. Not obtained.
Poitier, A. de (date?) Bait digging in Chichester Harbour. Internal report to Chichester Harbour Conservancy. Not obtained.
Povey, A. and Keough, M.J. 1991. Effects of trampling on plant and animal populations on rocky shores. Oikos 61: 355-368. Quoted in Quigley and Frid 1998. Not reviewed.
Quigley, M.P. and Frid, C.L.J. 1998. Draft management report: The ecological impacts of the collection of animals from rocky intertidal reefs (pp. 42). A report to English Nature from the Dove Marine Laboratory, Cullercoats, North Shields, Tyne and Wear, NE30 4PZ. Supported by the European ‘LIFE’ Programme. Reviews nature and scale of collecting activities upon rocky intertidal reefs within the Berwickshire and North Northumberland cSAC. Sets out options for management and recommendations to address issues identified. Target organisms were Carcinus maenus, Cancer pagurus and Littorina littorea. Main recommendations were for monitoring the activity and establishing a zonation scheme with no-take zones in representative pristine sites throughout the SAC to act as a source of recruits.
Rees, H.L. and Eleftheriou A. 1989. North Sea benthos: A review of field investigations into the biological effects of man’s activities. J.Cons.int.Expl.Mer. 54(3): 284-305. Reviews several of the papers listed here in assessing effects of anthropogenic activity on the benthos. Notes increase in bio-availability of lead and cadmium (Howell 1985), and species and community effects reported by several authors.
Robson, E.M. and Williams, I.C. 1971. Relationships of some species of Digenea with the marine prosobranch Littorina littorea (L.). II. The effect of larval Digenea on the reproductive biology of L.littorea. J. Helminthology. 45, 145-149. Winkles are rarely affected by parasitic trematodes prior to first spawning. As they grew older, rate of infection grew exponentially. Trematode infections so reduce egg production by affected females that in some populations the entire egg production comes from first-time spawners.
Roch, P., Giangrande, A., & Canicatti, C. 1990. Comparison of hemolytic activity in eight species of polychaetes. Marine Biology. 1990. vol. 107, no. 2, pp. 199-203. Included in this review because they mention a purchase from a retail shop in Italy of a Nereis sp. imported from the Yellow Sea, Japan.
Scott, F.E. 1989. Human disturbance of wading birds on the Ythan Estuary. Unpub. BSc thesis, Department of Zoology, University of Aberdeen. Considers limited disturbance by bait diggers to have relatively little effect on feeding waders.
Shackley, S.E., Coates, P.J., and Giesbrecht, G.E. 1995. Cockles and Bait Digging in the Burry Inlet. Burry Inlet and Loughor Estuary Symposium: State of the estuary report, Part 2; Supplementary Proceedings to the Burry Inlet Symposium 1995. An experimental investigation into the effects of bait digging on cockles. Substratum turned over and broken up to a depth of about 30 cm. Compared effects of backfilling and digging trenches with spoil heaps. Both methods caused over 90% cockle mortality (probably through burial) within 6 days. Differences between controls and dug plots still detectable after 3 months. Older cockles more susceptible to effects of digging. Backfilling less damaging because a smaller surface area affected than by using trench and spoil heap method.
Shahid, M.H.S. 1982. The reproductive biology, population genetics and population dynamics of the lugworm Arenicola marina in relation to bait digging on the Northumberland coast. PhD Thesis. University of Newcastle upon Tyne. Most lugworms breed between October and March, usually in November and December, although up to 20% of the population may spawn in July to September. Each animal spawns on a single day, with the entire population of a beach completing spawning within just a few days. Populations on different beaches breed at different times.
Sharpe, A.K., and Keough, M.J. 1998. An investigation of the indirect effects of intertidal shellfish collection. Journal of Experimental Marine Biology and Ecology. 223:19-38. Quoted in Quigley and Frid 1998. Not reviewed.
Sherman, K.M. & Coull, B.C. 1980. The response of meiofauna to sediment disturbance. Journal of Experimental Marine Biology and Ecology, 46, 59-71. Not reviewed.
Siegfreid, W.R. (ed.) 1994. Rocky shores – exploitation in Chile and South Africa. Ecological Studies Vol. 103. 177pp. Springer-Verlag.  
Simpson, J. 1992. Preliminary research into bait digging in Pagham Harbour. No publication details. Aimed to ascertain bait digging pressures, location and distribution of the main beds and to establish suitable long-term survey techniques prior to a five year investigation into ecological implications (West Sussex).
Smit, C.J. and Visser, G.J.M 1993. Effects of disturbance on shorebirds: a summary of existing knowledge from the Dutch Wadden Sea and Delta Area. Wader Study Group Bulletin. 68: 6-19. Quoted in Quigley and Frid 1998. Not reviewed.
Stour and Orwell estuaries group. (date?) Stour and Orwell estuaries management plan. Lists concerns about bait digging. Policy LR4 states: Promote understanding and the necessary control to provide a sustainable level of bait digging.
Suffolk Coasts and Heaths Project. (date?) Stour and Orwell estuaries management plan issues. Identifies issues resulting from bait digging.
Tamar Estuaries Bait Collection Working Group. 1998. The Working Group was set up when bait collection (particularly the level and impact of crab trapping and worm digging and the abuse of access and property rights) was identified as an issue of concern by the Tamar Estuaries Management Plan Consultative Document. The Group is comprised of recreational and commercial collectors and recreational marine fishery bodies. It notes that there are some 20,000 crab traps in the Tamar Estuaries, of which some 8,000 are commercially used. Commercial traps yield some 90,000 crabs, recreational anglers collect some 20,000. Approximately 70% of the commercial yield is sold to other parts of the UK. Most worm digging is carried out by recreational anglers. The Group recommends a voluntary management approach involving all key players, in harmony with the Tamar Estuaries Management Plan. Improved public awareness, production of a local bait collectors’ code and an educational programme, surveys, monitoring and zoning of activity are all recommended.
Townshend, D.J. and O’Connor, D.A. 1993. Some effects of disturbance to waterfowl from bait digging and wildfowling at Lindisfarne National Nature Reserve, north-east England. In: Davidson, N. and Rothwell, P. Disturbance to waterfowl on estuaries. Wader Study Group Bulletin, 68:47-52. Bait digging activity greatly reduced the extent of use of the area by several waterfowl species, apparently through the direct effects of disturbance. Large numbers of people were spread across the tidal flats disturbing waterfowl attempting to use the wildlife refuge. Average peak winter numbers of wigeon and two of the main wader species (bar-tailed godwit and redshank) before and after restrictions on bait digging showed that in years when bait digging took place on all or parts of the Bay the numbers were substantially lower than in years when there was no bait digging. The difference was most marked for wigeon. These differences were not considered to be due to between-year differences in the local populations, as it was a larger proportion of the Lindisfarne population which used the Bay, implying that it may be a preferred area for these species and that birds which would otherwise have fed there were prevented from doing so by the presence of bait diggers. Substantial increases in the populations of four other species of wildfowl using Budle Bay were also recorded in the year following prohibition of bait digging (inc. 119% for shelduck, 700% for wigeon).
Underwood, A.J. 1993. Exploitation of species on the rocky coast of New South Wales (Australia) and options for its management. Ocean and Coastal Management 20, 41-62. Summarised the widespread, continuous and destructive patterns of human harvesting of intertidal and subtidal invertebrates and algae, the nature and types of catches, and the intensity of the activity on the rocky coast of New South Wales. Direct effects include the loss of individuals removed from breeding populations. Indirect effects include loss of prey items for other species, and loss of habitat. Management options, including general or selective bag limits, bans on harvesting for food and bait on the whole coast or in selected areas, are reviewed. Complete and enforced closure of certain areas is considered to be the only realistic option. Criteria for selection and needs for public education and monitoring to determine effectiveness are briefly discussed.
Wash management strategy discussion papers. September 1990. Papers on public access, recreation and bait digging.
Wege, D.C. 1987. The effect of boulder turning by bait collectors on intertidal boulder fauna. University College of Wales, Swansea. Report to the Nature Conservancy Council. CSD Report. Results published in Liddiard et al. 1989.