Higher taxa can be effective surrogates for species‐level data in detecting changes in invertebrate assemblage structure due to disturbance: a case study using a broad range of orders

Cost‐effective assessment tools are needed to manage the impacts of natural and human disturbances on communities. Higher taxa are widely used as surrogates for species‐level identification in invertebrates; however, few studies have compared their effectiveness with species‐level data for terrestrial invertebrates or assessed the mechanistic basis for their performance, and none of these studies have used a broad range of orders. Here, a terrestrial invertebrate dataset comprising 21 orders, 197 families and 751 species was used to investigate whether order‐ and family‐level identifications were effective surrogates for species‐level identification in representing patterns in assemblage structure and detecting the effects of fire. Factors potentially influencing the performance of surrogates among invertebrate orders were also investigated. Family‐level identification of invertebrates in moorland sites with a wide range of fire history was found to be an effective surrogate for species‐level identification. Order‐level identification was also an effective surrogate, but the level of discrimination among sites was typically lower than for species‐ or family‐level identification. Higher taxonomic surrogates performed well for invertebrate orders comprising a few species that were abundant and with a small mean and variance in the number of species per higher taxon. Use of higher taxa as surrogates for species‐level identification can be a cost‐effective approach to monitoring impacts of disturbance, but outcomes are influenced by taxonomic diversity and community structure.