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The original descriptions of nine monodontid and 21 delphinid nominal taxa were revisited, thereby revealing necessary addenda and corrigenda elucidating and solving earlier problems of cetacean nomenclature. This report provides further notes and is an addition to the 2021 work of Jefferson entitled Nomenclature of the Dolphins, Porpoises, and Small Whales: A Review and Guide to the Early Taxonomic Literature (NOAA Professional Paper NMFS 21). [ABSTRACT FROM AUTHOR]

Two species of sea lions occur in the inland waters of Washington State: the California sea lion (Zalophus californianus) and the Steller sea lion (Eumetopias jubatus). Both species breed elsewhere, but they typically move into Puget Sound and adjacent waters of the Salish Sea from autumn through spring. There is a need for information on their current abundance and seasonal use patterns as both species prey heavily on threatened/ endangered stocks of salmon and steelhead trout (Oncorhynchus spp.), and empirical abundance estimates of these species are lacking for inland Washington waters. From 2013 to 2016, we conducted 39,399 km of aerial surveys for marine mammals in this area, sighting 255 groups of sea lions. We used a subset of 7,841 km of effort and 165 sea lion sightings made during surveys in good sighting conditions to estimate in-water abundance using line-transect methods. Historical tagging data collected in Pacific Northwest waters were used to evaluate the proportions of time that each species spent on land and conducting dives, and then to develop correction factors to derive total abundance for both sea lion species, providing the first empirical abundance estimates for these waters. We estimated that between 33 and 442 California sea lions were found in Puget Sound/ Hood Canal in different seasons, with nearly 3,000 being found in the broader inland Washington waters in the peak season (spring). Steller sea lions occurred in much smaller numbers, with a peak of 219 animals in Puget Sound/Hood Canal/Strait of Juan de Fuca in autumn (and possibly as many as 600 to 700 in the entire study area). While some estimates suffer from low precision, this study demonstrates that substantial numbers of sea lions use waters of the study area throughout much of the year. Our results provide an important step toward a better understanding of these two species in the inland waters of Washington, as well as their potential effects on protected salmonid prey species. [ABSTRACT FROM AUTHOR]

The purpose of this note is to retain five names of small cetaceans--Delphinapterus leucas (Pallas, 1776) for the beluga whale, Tursiops truncatus (Montagu, 1821) for the common bottlenose dolphin, Lissodelphis borealis (Peale, 1849) for the northern right whale dolphin, Cephalorhynchus eutropia (Gray, 1846) for the Chilean dolphin, and Inia geoffrensis (Blainville in Desmarest, 1817) for the Amazon river dolphin--that are each threatened by synonyms that antedate their currently used names. In each case, the earlier name has rarely or never been used in the past 120 years, and its resurrection as the valid name for these species would threaten stability. Prevailing usage must be maintained to favor stability over priority in accordance with Article 23.9 of the International Code of Zoological Nomenclature. I request that in each case listed, the designated junior synonym be henceforth considered a nomen protectum (and thereby continue to be used as the valid name for the relevant taxon) and that each of the indicated senior synonyms be treated as a nomen oblitum (i.e., forgotten name). [ABSTRACT FROM AUTHOR]

Within the past several decades, Indo-Pacific humpback dolphins (Sousa chinensis) in Hong Kong have gone from being virtually unknown to being probably the best-studied dolphin population in Southeast Asia. Essentially nothing was known of their status prior to 1993, but they are now understood to be part of a large population (> 2,000 individuals) that inhabits the Pearl River Estuary of southern China. Approximately 130 to 200 dolphins occurred within Hong Kong's boundary in the late 1990 and early 2000s, but the numbers have declined since then, with currently only about 65 to 70 dolphins found within the region at any one time. Despite an ambitious management scheme by the Hong Kong Agriculture, Fisheries, and Conservation Department, mostly involving Hong Kong's Environmental Impact Assessment (EIA) legislation, the dolphins appear to be at risk locally. A series of recommendations are hereby made to encourage improved management of these animals and include (1) management at the population level; (2) better assessment of cumulative impacts; (3) protection of critical habitat, especially along the west coast 01 Lantau Island; and (4) management with "teeth." If these suggested approaches are vigorously followed, I remain optimistic about the future of humpback dolphins in Hong Kong. Historical data show us that these animals can indeed recover from anthropogenic impacts but only if important habitat areas receive better protection than they are getting at present. [ABSTRACT FROM AUTHOR]

The article discusses a study on the instances of collision of Sperm Whale with commercial and recreational ships into oceans. It mentions accidental collision which occurs frequently along with rare occurrence of intentional ramming events. It also discusses events of sperm whales destroying small and light whaling chase boats by hitting them with their bodies and flukes.

Studies on the distribution and habitat characteristics of the Indo-Pacific humpback dolphin (Sousa chinensis) indicate a general preference toward estuarine environments. However, quantitative connections between this preference and estuarine characteristics are seldom investigated. Distribution of the humpback dolphin in the northern Beibu Gulf, China, was evaluated through systematically designed surveys and was compared to oceanographic characteristics from on-board measured and remotely sensed variables. The humpback dolphins' core distribution zone, measured by the 50% kernel density estimate (50% KDE), was confined to the Dafengjiang River Estuary in a 50.23 km² area, with a steep-edged underwater sand bar below and locally high chlorophyll-a concentration. The surface salinity distribution showed an eco-cline environment in which riverine runoff mixes with sea water in the 50% KDE. We found significant relationships between distribution probability and two oceanographic variables: (1) water depth and (2) chlorophyll-a concentration. This associates the distribution preference of humpback dolphins with regional productivity and biodiversity peaks that may facilitate prey aggregation. As humpback dolphins inhabit comparable environments in other locations throughout their range, the oceanographic features of the 50% KDE may help to provide proxies to identify other key habitats over a broader spatial scale. [ABSTRACT FROM AUTHOR]

The relative occurrence of the 16 most common cetacean species in the Southern California Bight (SCB) was compared from the 1950s through 2012 by examining at-sea sighting and stranding data. While systematic survey and population abundance/density data have been available since the 1970s, prior data were collected opportunistically. Comparisons were made through a literature review and using recent results from 15 aerial surveys conducted in the SCB from 2008 through 2012. We attempted to address inconsistency in type of effort across studies by ranking the relative sighting frequency of the most common species based on the most representative study for each period. This comparison revealed changes in the relative occurrence of some species across the approximately 60-y reviewed period. Since the 1950s, common dolphins have remained the most common "species" of cetacean in the SCB. Risso's dolphin and fin, blue, humpback, and Bryde's whales appear to have increased in relative occurrence. The relative occurrence of the common bottlenose and northern right whale dolphins; Dall's porpoise; and gray, killer, minke, Cuvier's beaked, and sperm whales do not appear to have changed notably since the 1950s. There is possible indication of recent decreased relative occurrence of the Pacific white-sided dolphin. The short-finned pilot whale has decreased since the 1950s and has not been recorded in the SCB since the 1990s, concurrent with the observed relative increase in Risso's dolphins. Overall, recent aerial surveys indicate that the 16 most commonly seen species in the SCB, in descending order of frequency, were common dolphins (two species), Risso's dolphin, fin whale, common bottlenose dolphin, gray whale, blue whale, Pacific white-sided dolphin, humpback whale, northern right whale dolphin, common minke whale, Dall's porpoise, killer whale, Bryde's whale, Cuvier's beaked whale (the latter three tied in ranking), and sperm whale. Given that the reviewed historical data from the 1950s and 1960s are virtually the only sources of information available to examine trends over the last 50 to 60 y in this area, we believe this comparative ranking approach provides useful information not available from other sources. [ABSTRACT FROM AUTHOR]

The relative occurrence of the 16 most common cetacean species in the Southern California Bight (SCB) was compared from the 1950s through 2012 by examining at-sea sighting and stranding data. While systematic survey and population abundance/density data have been available since the 1970s, prior data were collected opportunistically. Comparisons were made through a literature review and using recent results from 15 aerial surveys conducted in the SCB from 2008 through 2012. We attempted to address inconsistency in type of effort across studies by ranking the relative sighting frequency of the most common species based on the most representative study for each period. This comparison revealed changes in the relative occurrence of some species across the approximately 60-y reviewed period. Since the 1950s, common dolphins have remained the most common "species" of cetacean in the SCB. Risso's dolphin and fin, blue, humpback, and Bryde's whales appear to have increased in relative occurrence. The relative occurrence of the common bottlenose and northern right whale dolphins; Dall's porpoise; and gray, killer, minke, Cuvier's beaked, and sperm whales do not appear to have changed notably since the 1950s. There is possible indication of recent decreased relative occurrence of the Pacific white-sided dolphin. The short-finned pilot whale has decreased since the 1950s and has not been recorded in the SCB since the 1990s, concurrent with the observed relative increase in Risso's dolphins. Overall, recent aerial surveys indicate that the 16 most commonly seen species in the SCB, in descending order of frequency, were common dolphins (two species), Risso's dolphin, fin whale, common bottlenose dolphin, gray whale, blue whale, Pacific white-sided dolphin, humpback whale, northern right whale dolphin, common minke whale, Dall's porpoise, killer whale, Bryde's whale, Cuvier's beaked whale (the latter three tied in ranking), and sperm whale. Given that the reviewed historical data from the 1950s and 1960s are virtually the only sources of information available to examine trends over the last 50 to 60 y in this area, we believe this comparative ranking approach provides useful information not available from other sources. [ABSTRACT FROM AUTHOR]

The estuaries and tidal rivers of the Gulf of Maine have rarely been surveyed systematically for marine mammals. We report here on three years of survey data, 2017 to 2019. This study employed a shipboard visual line-transect methodology study design, collecting data on marine mammals in the lower Piscataqua River, which is confluent with the Gulf of Maine. Marine mammal species observed most often were harbor seals (Phoca vitulina) and gray seals (Halichoerus grypus), with a resulting in-water density estimate of 1.02 seals/km2 and an abundance estimate of seven harbor seals and one gray seal (CV = 19.3%) in the survey area. Seals were present in all months of the year. No live pups were detected. Harbor porpoises (Phocoena pho-coena) and minke whales (Balaenoptera acuto-rostrata) were also observed, but the sightings (6 harbor porpoises; 7 minke whales) did not yield enough data to estimate density or abundance. The minke whales were present during August and September 2018, concurrent with an influx of Atlantic menhaden (Brevoortia tyrannus), a prey species. The consistent albeit relatively low marine mammal species sightings and abundances suggest that the lower Piscataqua River is used regularly by a relatively small number of harbor and gray seals, although not for pupping, and occasionally by harbor porpoises and by foraging minke whales. This is the first study of its kind in an estuarine environment in the Gulf of Maine. [ABSTRACT FROM AUTHOR]

Until the last few years, the only records of Indian Ocean humpback dolphins (Sousa plumbea) in Sri Lanka were a small number of older stranding records and one unconfirmed sighting, but repeated verified sightings have been made since the early 2000s in the Puttalam Lagoon area of northwestern Sri Lanka. To determine dolphin status and distribution patterns, we conducted monthly surveys of the lagoon from July 2010 to June 2011 and sighted humpback dolphins in the lagoon in every month of the year. Repeated sightings of the same six individuals were made; and in March 2011, one of these humpback dolphins was killed by dynamite fishing. It appears that the population is very small, possibly now consisting only of these five individuals, and is resident in the lagoon. Although it is likely the species was more widespread and abundant in the past, it appears that Puttalam Lagoon may be the only location where this species persists in Sri Lanka at present. Additional research is needed to investigate possible mixing with populations in India, and urgent conservation measures are recommended to ensure the long-term survival of this enigmatic species in Sri Lanka. [ABSTRACT FROM AUTHOR]

The article offers information on Bryde's whales also known as Balaenoptera edeni with details on their foraging region which lies near the Weizhou Island of China in the Beibu Gulf. Topics discussed include occurrence of Bryde's whale strandings along the coasts of China, conduction of vessel-based photo-identification surveys of the whales and details on their sightings.

In the early 1970s. Roger Payne and colleagues developed a non-invasive, shore-based method for collecting data on free-ranging marine mammals in their natural environments. By using a theodolite, or surveyor's transit, they were able to collect data on nearshore marine mammal movement patterns, habitat use, and behavior without any disruption to the animals. As technology advanced, theodolite data collection progressed from analog machines requiring manual data entry to digital equipment linked to computer software that facilitated data management and automated calculations of marine mammal positional information. There are limitations associated with theodolite use, and concurrent data collection methods can contribute information that may not be possible with shore-based research alone. Since the first published research in 1978 using a theodolite to describe the behavioral ecology of dolphins off Argentina, at least 46 species of marine mammals in 36 countries have been tracked by theodolite, and the method continues to be used globally to contribute to non-invasive marine mammal research, conservation, and management. [ABSTRACT FROM AUTHOR]

The article focuses on the sightings of Bryde's whale in Southern California Bight (SCB) between California and Mexico. It mentions that one sighting of Bryde's wale was confirmed in La Jolla in San Diego, California and another one in Monterey Bay. Furthermore, the sightings usually happen over areas with bottom depths ranging up to 5,000 meters, which are estimated to be 75-120 kilometers away from the Southern California coast.