Given new distribution patterns of the endangered North Atlantic right whale (NARW; Eubalaena glacialis) population in recent years, an improved understanding of spatio-temporal movements are imperative for the conservation of this species. While so far visual data have provided most information on NARW movements, passive acoustic monitoring (PAM) was used in this study in order to better capture year-round NARW presence. This project used PAM data from 2004 to 2014 collected by 19 organizations throughout the western North Atlantic Ocean. Overall, data from 324 recorders (35,600 days) were processed and analyzed using a classification and detection system. Results highlight almost year-round habitat use of the western North Atlantic Ocean, with a decrease in detections in waters off Cape Hatteras, North Carolina in summer and fall. Data collected post 2010 showed an increased NARW presence in the mid-Atlantic region and a simultaneous decrease in the northern Gulf of Maine. In addition, NARWs were widely distributed across most regions throughout winter months. This study demonstrates that a large-scale analysis of PAM data provides significant value to understanding and tracking shifts in large whale movements over long time scales.

Long‐term identification surveys were conducted using video records on Indo‐Pacific bottlenose dolphin (Tursiops aduncus) around Mikura Island, Tokyo, Japan. On 246 surveys, 3,996 min of video were recorded during each summer season from 1994 to 2001. Two hundred and twenty individuals were observed, including juveniles and neonates, that were not cataloged, but could be identified by association with their mothers. Over the eight‐year study period, the total number of identified and cataloged individuals was 169. The annual number of newly identified dolphins stabilized at ∼ 10 after 1995. In the middle of each research season, a plateau in the number of reidentified individuals was reached. Most of the dolphins were observed frequently–percentages of reidentified dolphins in adjoining years were greater than 86% and 62 individuals were seen consecutively during the eight years. There were no significant differences in the sex ratio between years. The sex ratio was skewed significantly towards male for subadults and towards female for adults. The survival rate of one‐year‐old calves was 86.7%, and the mean age at weaning was 3.5 yr. The calving interval averaged 3.4 yr among adult females. The mean annual birth, fecundity, and recruitment rates were 0.071, 0.239, and 0.068, respectively. Mikura Island is located in the pelagic ocean with no protected bay area existing around the island. Dolphins do not regularly inhabit any other locations besides Mikura within the Izu island chain. Thus, this island may be important core habitat of these dolphins.

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The presence of endangered North Atlantic right whales Eubalaena glacialis in the mid-Atlantic region of the USA is not well understood. Adequate protection of right whales in the face of plans to develop offshore renewable energy requires more information about this species' distribution and occurrence in this region. We present findings from the first year-round study dedicated to marine mammals in New Jersey's nearshore waters using line transect surveys and passive acoustic monitoring. Four groups of right whales, including a cow−calf pair, were sighted. Right whales were detected acoustically during all seasons. Sightings of females and subsequent confirmations of these same individuals in the calving grounds a month or less later illustrate that these waters are part of this species' migratory corridor. Observations of skim-feeding behavior suggest that feeding may also occur in areas farther south than the main feeding grounds. Based on the year-round occurrence of right whales off New Jersey, we recommend that presumed seasonal migratory patterns not be used alone to determine the timing of construction activities or monitoring/mitigation efforts for offshore development. Our results also provide support for the expansion of existing critical habitat to include nearshore waters of the mid-Atlantic.

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