Right Whale Occurrence Research Articles

Persistent near real‐time passive acoustic monitoring for baleen whales from a moored buoy: System description and evaluation

Abstract Managing interactions between human activities and marine mammals often relies on an understanding of the real‐time distribution or occurrence of animals. Visual surveys typically cannot provide persistent monitoring because of expense and weather limitations, and while passive acoustic recorders can monitor continuously, the data they collect are often not accessible until the recorder is recovered. We have developed a moored passive acoustic monitoring system that provides near real‐time occurrence estimates for humpback, sei, fin and North Atlantic right whales from a single site for a year, and makes those occurrence estimates available via a publicly accessible website, email and text messages, a smartphone/tablet app and the U.S. Coast Guard's maritime domain awareness software. We evaluated this system using a buoy deployed off the coast of Massachusetts during 2015–2016 and redeployed again during 2016–2017. Near real‐time estimates of whale occurrence were compared to simultaneously collected archived audio as well as whale sightings collected near the buoy by aerial surveys. False detection rates for right, humpback and sei whales were 0% and nearly 0% for fin whales, whereas missed detection rates at daily time scales were modest (12%–42%). Missed detections were significantly associated with low calling rates for all species. We observed strong associations between right whale visual sightings and near real‐time acoustic detections over a monitoring range 30–40 km and temporal scales of 24–48 hr, suggesting that silent animals were not especially problematic for estimating occurrence of right whales in the study area. There was no association between acoustic detections and visual sightings of humpback whales. The moored buoy has been used to reduce the risk of ship strikes for right whales in a U.S. Coast Guard gunnery range, and can be applied to other mitigation applications.

Southern right whales in the South-western Atlantic Ocean: proposed criteria to identify suitable areas of use in poorly known reproductive grounds

AbstractUrbanization and intense vessel traffic in coastal areas are obstacles for right whales when selecting breeding and calving grounds. Human activities might be the main cause for the recently observed drop in right whale sightings along the south-eastern coast of Brazil. Information concerning the biology and the activities that can potentially affect the presence of individuals along the coast are essential for management purposes, as well as for the recovery of the species stocks after a period of whaling pressure. This study correlated the occurrence of right whales in the northern limit of the breeding ground in the South-western Atlantic Ocean with local geomorphology, degree of urbanization and oceanographic features to better identify suitable areas for use by these whales. The study area was divided into 14 sub-areas based on local coastal geomorphology and discharge of large rivers. The following five ranking criteria were applied to each sub-area: presence of whaling stations and whaling activity in the past; presence and activity of ports; protection from swell, coastal slope and composition of the bottom substrate. The sub-areas that offered conditions conducive to the presence of right whales received higher scores. The proposed criteria were validated by overlapping the ranking scores with the records of right whales sighted in each sub-area. In south-eastern Brazil, protected areas with sandy bottom and gentle slope were associated with more sightings of female-calf pairs. The criteria can be used as a primary diagnostic indicating suitable sub-areas for right whales in poorly known breeding grounds.

North Atlantic right whale occurrence near wind energy areas along the mid-Atlantic US coast: implications for management

The distribution and seasonal patterns of the North Atlantic right whale, Eubalaena glacialis, inform management decisions that mitigate anthropogenic threats. Based on data from visual surveys, much of the population migrates between winter calving grounds in coastal waters adjacent to the southeast USA and summer feeding and nursery grounds adjacent to the northeast USA. However, little is known about right whale occurrence along the mid-Atlantic US migratory corridor. A better understanding of right whale occurrence in this region is needed prior to off- shore wind energy development activities, which may increase mortality risks and chronic impacts on the population. We conducted an 11 mo passive acoustic survey along coastal North Carolina and Georgia near several wind energy areas to document the acoustic occurrence of right whales in the southern region of the mid-Atlantic US coast. Right whales were acoustically detected across all seasons, with peak seasonal presence occurring during autumn in the Georgia site and during winter in the North Carolina site. A secondary peak in presence also occurred dur- ing June and July in the Georgia site, when right whales were not expected to be in the area. Given the nearly year-round presence of right whales in the survey areas, these results may war- rant an evaluation of current management protocols in order to provide adequate protection to the population in the face of offshore energy development activities.

North Atlantic right whale distribution and seasonal occurrence in nearshore waters off New Jersey, USA, and implications for management

ESR Endangered Species Research Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsSpecials ESR 20:59-69 (2013) - DOI: https://doi.org/10.3354/esr00486 North Atlantic right whale distribution and seasonal occurrence in nearshore waters off New Jersey, USA, and implications for management Amy D. Whitt*, Kathleen Dudzinski, Jennifer R. Laliberté Geo-Marine, Inc., 2201 K Avenue, Suite A2, Plano, Texas 75074, USA *Email: adwhitt@gmail.com ABSTRACT: 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. KEY WORDS: Eubalaena glacialis · North Atlantic right whale · Seasonality · Distribution · Conservation · Passive acoustic monitoring · Surveys Full text in pdf format PreviousNextCite this article as: Whitt AD, Dudzinski K, Laliberté JR (2013) North Atlantic right whale distribution and seasonal occurrence in nearshore waters off New Jersey, USA, and implications for management. Endang Species Res 20:59-69. https://doi.org/10.3354/esr00486 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in ESR Vol. 20, No. 1. Online publication date: March 21, 2013 Print ISSN: 1863-5407; Online ISSN: 1613-4796 Copyright © 2013 Inter-Research.