Invertebrate community responses to recreational clam digging

Size and Abundance of Pismo Clams in the Intertidal and Subtidal

“…Here, we explore the impact of recreational fishing, wave action, and predation by non-human predators on the abundance and distribution of Pismo clams. Recreational fishing is known to alter the abundance and size distribution of several species of marine invertebrates (Griffiths et al, 2006;Cecilia et al, 2005;Alexander et al, 2014). However, for the Pismo clam population at Rincon Beach, CA, recreational fishing appears to only affect the distribution of legal-sized clams, not overall abundance.…”

“…In the study area, clams of about 30mm in length were targeted, and in areas with higher human access, there was a greater abundance of 20-25mm individuals, just below the targeted size (Cecilia et al, 2005). A study that compared no-take reserves to areas where recreational harvesting is permitted found that clam digging had a substantial influence on decreasing the abundance of target species within legal take size ranges (Griffiths et al, 2006). In addition, Griffth et al (2006) specifically studied sites in which confounding effects, like wave energy, were minimized to pinpoint anthropogenic effects.…”

Immediate Effect of Clam Harvesting on Intertidal Benthic Communities in the Mudflat Zones of Kneiss Islands (Central Mediterranean Sea)

“…This may have a negative impact on the associated benthic infauna community, such as observed in the Lowes Cove communities from Walpole, Maine (USA) [1]. This disturbance could have a variety of effects depending on the benthic community, the surface-area disturbed and fishing pressure; all these factors vary between different fisheries and according the digging areas and fishing gear [2][3][4]. Nevertheless, many studies show that, in the intertidal zone, manual or mechanical harvesting of target intertidal bivalves may cause strong disturbances and negative effects on the benthic infauna communities, i.e.…”

Sustainability of bait fishing harvesting in estuarine ecosystems – Case study in the Local Natural Reserve of Douro Estuary, Portugal

“…When mud is turned over by hand rake and trampling, habitat destruction and direct mortality occurs (Logan, 2005;Sypitkowski et al, 2010). Infauna is exposed on the mud surface, thereby increasing the chance of either predation or desiccation (Ambrose 1986;Griffiths et al, 2006;Rossi et al, 2007). Morevoer, infauna biophysical structures, such as worm tubes, are often destroyed (Rossi et al, 2007;Sypitkowski et al, 2010).…”

“…This undefined exploitation contributes to a parallel economy and directly conflicts with a sustainable and controlled activity (Costa et al, 2006). Some degree of protection in marine areas can help in biodiversity conservation and potentially be useful as a management tool of exploitation of marine resources, removing or reducing relevant negative anthropogenic impacts (Griffiths et al, 2006;Hardiman & Burgin, 2010). Intertidal soft-sediment habitats can often support robust recreational and commercial harvests, however there is limited research on the effects of reserves in these habitats (Griffiths et al, 2006).…”