A new paper by Vasco und Florian has just been published in PLOS ONE. In the study, we were able to detect over 80% of invertebrate taxa from a bulk samples using DNA metabarcoding. Further more we showed that with PCR based methods, estimating taxon abundance is not possible in such diverse bulk samples. Monitoring should thus focus primarily on presence absence data instead. More information in a press release here.
Elbrecht V, Leese F (2015) Can DNA-Based Ecosystem Assessments Quantify Species Abundance? Testing Primer Bias and Biomass—Sequence Relationships with an Innovative Metabarcoding Protocol. PLoS ONE 10(7): e0130324. doi:10.1371/journal.pone.0130324