Dear Colleagues, We have just published details of a study in which we have investigated the ability to detect species presence by amplifying ‘environmental DNA’ (eDNA) in samples of seawater. For this proof of concept study we used small samples (15-50 ml) and targeted sequencing to allow direct comparison with published freshwater studies, but this meant we had a high proportion of false negative detections. However, our colleagues have used filtrate from larger volumes of seawater and using the Roche GS FLX 454 pyrosequencing have been able to detect a number of fish species comparable with, or even bettering, results from traditional survey methods for the same area. eDNA sampling therefore has the potential to compliment current acoustic and visual survey methods if the question is one regarding species presence/absence. It should be noted that eDNA is very fragmented, often <100bp, and this sampling method is not a suitable alternative to biopsy sampling for population genetics. Below are the links to access both papers. PLoS One is open access and so everyone with internet access should be able to get a copy. Foote AD, Thomsen PF, Sveegaard S, Wahlberg M, Kielgast J, Kyhn LA, Salling AB, Galatius A, Orlando L, Gilbert MTP (2012) Investigating the potential use of environmental DNA (eDNA) for genetic monitoring of marine mammals. PLoS one http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0041781 Thomsen PF, Kielgast J, Lønsmann Iversen L, Rask Møller P, Ramussen M, Willerslev E (2012) Detection of a diverse marine fish fauna using environmental DNA from seawater samples. PLoS one http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0041732 Andy Foote -- *Dr Andrew Foote* *Centre for GeoGenetics* The Natural History Museum of Denmark Øster Voldgade 5 - 7 1350 Copenhagen K