Dear colleagues, My co-authors and I are pleased to announce the publication of the following article: Passive acoustic monitoring reveals spatio-temporal distributions of Antarctic and pygmy blue whales around central New Zealand. Victoria E. Warren, Ana Sirovic, Craig McPherson, Kimberly T. Goetz, Craig A. Radford and Rochelle Constantine. Frontiers in Marine Science, 2021, https://doi.org/10.3389/fmars.2020.575257 IN A NUTSHELL We've known for a long time that two sub-species of blue whale occur in New Zealand waters (Antarctic blue whales and pygmy blue whales), but they've often been lumped together as it's tricky to tell the difference between them by eye. Luckily they produce very different sounds, so using acoustic monitoring we were able to distinguish between them and uncover the differences in their distributions over time and space. ABSTRACT Effective management of wild animal populations relies on an understanding of their spatio-temporal distributions. Passive acoustic monitoring (PAM) is a non-invasive method to investigate the distribution of free-ranging species that reliably produce sound. Critically endangered Antarctic blue whales (*Balaenoptera musculus intermedia*) (ABWs) co-occur with pygmy blue whales (*B. m. brevicauda*) (PBWs) around New Zealand. Nationally, both are listed as “data deficient” due to difficulties in access and visual sub-species identification. PAM was used to investigate the distributions of blue whales *via* sub-species specific song detections in central New Zealand. Propagation models, incorporating ambient noise data, enabled the comparison of detections among recording locations in different marine environments. ABW detections peaked during austral winter and spring, indicating that New Zealand, and the South Taranaki Bight (STB) in particular, is a migratory corridor for ABWs. Some ABW calls were also detected during the breeding season (September and October). PBW calls were highly concentrated in the STB, particularly between March and May, suggesting that an aggregation of PBWs may occur here. Therefore, the STB is of great importance for both sub-species of blue whale. PBW detections were absent from the STB during parts of austral spring, but PBWs were detected at east coast locations during this time. Detection area models were valuable when interpreting and comparing detections among recording locations. The results provide sub-species specific information required for management of critically endangered ABWs and highlight the relative importance of central New Zealand for both sub-species of blue whale. The open-access article can be downloaded from https://www.frontiersin.org/articles/10.3389/fmars.2020.575257 You are very welcome to contact me via email (vwar775@aucklanduni.ac.nz) if you have any questions. Kind regards, Victoria Warren -- Victoria Warren PhD Candidate, University of Auckland +64-4-386-0526 NIWA, 301 Evans Bay Parade, Greta Point, Wellington, New Zealand