Sampling macroinvertebrates in a temporary pond: comparing the suitability of two techniques to detect richness, spatial segregation and diel activity

Abstract

Recent and increasing interest in temporary ponds as biodiversity reservoirs fosters our need to test sampling techniques for characterising their biological communities. We compared the efficiency of dip-netting to that of fyke nets in sampling the macroinvertebrate assemblage of a temporary pond in Doñana National Park (SW Spain). We sampled the pond at four different times-morning, afternoon, evening and night-distinguishing between deep and shallow zones. In our sampling, dip-netting captured a higher number of taxa, and higher abundances of individuals than fyke nets. However, both techniques captured exclusive taxa, not recorded with the other device. Fyke nets distinguished between nocturnal and diurnal macroinvertebrates, and hence are more appropriate to study macroinvertebrate diel activity. We detected nocturnal activity in Gerris thoracicus larvae, and adults of Colymbetes fuscus, Rhantus suturalis, Rhantus hispanicus and Hydrochara flavipes. Conversely, larvae of Sympetrum fonscolombei and Notonecta spp., and adults of Notonecta glauca were mainly diurnal. The overall diel activity pattern of the macroinvertebrate assemblage depended on the diel activities of their integrating taxa and stages. Although dip-netting was more appropriate to sample macroinvertebrate assemblages in different microhabitats, fyke nets better captured nocturnal and fastswimming invertebrates. Consequently, the joint use of both sampling techniques would capture a better picture of the representative macrofauna of a temporary pond than either one on its own.

Change does not happen overnight: a case study on stream macroinvertebrates

“…For instance in lentic ecosystems, Florencio et al (2011) suggested that dip-netting was especially appropriate for sampling macroinvertebrates in different microhabitats, whereas fyke nets were a better option for capturing nocturnal and fast-swimming invertebrates. Similar problems may affect lotic ecosystems, where the use of a Surber sampler alone might not be capable of collecting fast-swimming invertebrates like some Coleoptera (e.g., family Gyrinidae), or skaters like aquatic Hemiptera (e.g., Gerridae).…”

“…feeding or avoiding predation, Elliott 2000Elliott , 2002Hampton and Duggan, 2003;Florencio et al, 2011). In a North American stream, for example, it has been observed that several caddisfly larvae (Sericostomatidae) burrow during the day and resurface at night (Bergey and Resh, 1994).…”

“…Likewise, marine and transitional (e.g., Guest et al, 2003) or lentic and temporary ecosystems (Marklund et al, 2001;Florencio et al, 2011) have been previously investigated, but less is known about riverine ecosystems and the entire stream macroinvertebrate community (see Copp et al, 2005, for an example in England).…”

Aquatic invertebrate assemblages in ponds from coastal Mediterranean wetlands

“…The absence of this group in fishless ponds (which were also the ones with high trophic level) could be caused by the shift from benthic to pelagic production as mentioned above, but also because of the lack of macrophytes. The sampling methodology used for large invertebrates (corer) could also have some limitations when sampling insects with high mobility in the water column, as these active taxa are more difficult to detect with usual sampling techniques for planktonic organisms (Florencio et al, 2012). Malacostraceans presented the highest richness in the recently created pond SA, which had total richness values similar to the other ponds.…”

“…Thus, their abundance is frequently difficult to estimate when the whole water column (including watersediment interface) is not completely sampled. In addition, the sampling methodology or the microhabitat sampled are often determinant to estimate the different community parameters (Garcı´a-Criado and Trigal, 2005;Florencio et al, 2012). Quantitative studies on aquatic invertebrates are mostly focused on microzooplankton (e.g., rotifers and juvenile copepods), macrozooplankton (e.g., adult copepods and cladocerans) or macroinvertebrates (e.g., bigger crustaceans and insects) separately, and usually interactions among them have not been largely considered.…”