Dear colleagues, My co-authors and I are pleased to announce the publication of the following article: Spatio-temporal variation in click production rates of beaked whales: Implications for passive acoustic density estimation. Victoria E. Warren, Tiago A. Marques, Danielle Harris, Len Thomas, Peter L. Tyack, Natacha Aguilar de Soto, Leigh S. Hickmott, and Mark P. Johnson The Journal of the Acoustical Society of America, 2017, Vol 141, Issue 3, 1962-1974; doi: http://dx.doi.org/10.1121/1.4978439 ABSTRACT Passive acoustic monitoring has become an increasingly prevalent tool for estimating density of marine mammals, such as beaked whales, which vocalize often but are difficult to survey visually. Counts of acoustic cues (e.g., vocalizations), when corrected for detection probability, can be translated into animal density estimates by applying an individual cue production rate multiplier. It is essential to understand variation in these rates to avoid biased estimates. The most direct way to measure cue production rate is with animal-mounted acoustic recorders. This study utilized data from sound recording tags deployed on Blainville's (Mesoplodon densirostris, 19 deployments) and Cuvier's (Ziphius cavirostris, 16 deployments) beaked whales, in two locations per species, to explore spatial and temporal variation in click production rates. No spatial or temporal variation was detected within the average click production rate of Blainville's beaked whales when calculated over dive cycles (including silent periods between dives); however, spatial variation was detected when averaged only over vocal periods. Cuvier's beaked whales exhibited significant spatial and temporal variation in click production rates within vocal periods and when silent periods were included. This evidence of variation emphasizes the need to utilize appropriate cue production rates when estimating density from passive acoustic data. The article can be downloaded from http://asa.scitation.org/doi/10.1121/1.4978439 or a PDF can be requested via email to victoriawarren@live.co.uk<mailto:victoriawarren@live.co.uk> Kind regards, Victoria Warren _____________________________________ Victoria Warren Alfred-Wegener-Institut Helmholtz-Zentrum für Polar und Meeresforschung Ocean Acoustics Lab, Room D-3035 Am Alten Hafen 26, 27568 Bremerhaven, Germany Email: victoria.warren@awi.de<mailto:victoria.warren@awi.de> Phone: +4947 14831 2212