Artificial Substrates

Artificial substrates are useful in a number of situations, though their use is usually restricted to hard substrates, as fixing an artificial substrate in a sedimentary environment without significantly altering the native habitat is difficult. They can be used to assess immigration or recruitment rates, temporal variation in assemblages using a standard habitat, or assessing diversity in areas where destructive sampling is not permitted.

The classic artificial substrate is the “tuffy” a plastic pan-scruber (those made by researchers here in Chile are known as a “Chuffy”). Tuffys are widely used to study the recruitment of invertebrates on the rocky shore. They can also be used to study colonization (not recruitment) of meiofauna of habitats on the rocky shore. In my experience meiofauna, particularly harpacticoid copepods will colonise the tuffy very quickly and they are certainly useful for identifying the biodiversity of a site without destructuve sampling.

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Tuffy “in action” at ECIM, Las Cruces (Region de Valparaiso)

 Other artificial substrates I have used include plastic doormats “Nomad”, astroturf and velcro. The idea is to select an artifical habitat that comes close to mimicing the micro habitat you wish to study. The plastic doormats mimic complex low turf forming algae species, as does astroturf which is similar in form to the alga Gellidium. I have use strips of velcro to mimic the alga Glossophora.

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The plastic doormat (above) and astrosturf (below) on the rocky shore at ECIM, Las Cruces (Region de Valparaiso)

Another semi-artificial habitat that I have used is the ‘live artificial mussel beds’. These were used to asses the differences in the biodiversity inside and outside the marine reserve at ECIM, Las Cruces (Region de Valparaiso). These consist of live mussels (in this casePerumytilus purpuratus) arranged on a plastic plate and fixed in place with plastic mesh.

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The assembly of the live artificial mussel beds, from right to left, the plate, with the mussels added, and the mesh that holds them in place. The live artificial mussel beds deployed in the field, within cages to prevent the mussels being eaten by their natural predators such as the loco (Concholepas concholepas)