Lagenorhynchus Acutus Research Articles

Fraser's dolphin (Lagenodelphis hosei) stranded in South Uist: first record in U.K. waters

AbstractOn 3 September 1996, B. Neill, investigating the peculiar behaviour of three ravens, found them disputing over a freshly dead dolphin stranded on the shore at Bornish, South Uist, Western Isles, Scotland (National Grid ref: NF 721 300). Neither he nor M. Bones, who collected the skeleton, could immediately identify the dolphin, despite having seen most of the species recorded around the Western Isles, although we suggested that it might be an Atlantic white‐sided dolphin Lagenorhynchus acutus with an aberrant colour pattern.

Aerial surveys of cetaceans in the Gulf of St. Lawrence in 1995 and 1996

Aerial line-transect surveys of cetaceans were flown in the Gulf of St. Lawrence in late August and early September of 1995 and in late July and early August of 1996. Systematic north-south transects were spaced 15prime of longitude apart. In 1995, the study area comprised the entire Gulf, divided into three strata for analysis; 69% was flown. In 1996, a single stratum covered only the north shore shelf; 75% of the design was flown. The survey platform was a light high-winged aircraft with bubble windows flown at 213 m (700 ft). Ten species were seen. Minke whales (Balaenoptera acutorostrata), Atlantic white-sided dolphins (Lagenorhynchus acutus), and harbour porpoises (Phocoena phocoena) yielded enough sightings to support good estimates, while fin whales (Balaenoptera physalus), humpback whales (Megaptera novaeangliae), white-beaked dolphins (Lagenorhynchus albirostris), and long-finned pilot whales (Globicephala melas) yielded few sightings and unreliable estimates. Blue whales (Balaenoptera musculus) and belugas (Delphinapterus leucas) were seen too rarely to support any analysis. The tenth species was a small delphinid, not positively identified. Minke whales were ubiquitous, but more common in the northern strata. We estimated about 1000 in the whole Gulf in 1995 and about 600 in the northernmost stratum in 1996 (these numbers, and those following, are uncorrected for visibility bias). We estimated about 12 000 Atlantic white-sided dolphins in the Gulf in 1995, but in 1996 saw hardly any, perhaps because we flew the survey earlier. Harbour porpoises (12 000 in 1995 and 21 000 in 1996) were most numerous in the northern stratum, but were also widely distributed at lower densities in the central and southern Gulf. White-beaked dolphins (2500 in 1995 and 2500 in 1996) occurred only in the Strait of Belle Isle and the extreme northeastern Gulf. We estimated a few hundred fin whales in the northern and central strata and about 100 humpbacks, mostly in the northeast. Long-finned pilot whales were only seen in the southeastern Gulf, surveyed only in 1995 (about 1500).

Interactions Between Dutch Midwater Trawl and Atlantic White-sided Dolphins(Lagenorhynchus acutus) Southwest of Ireland

Incidental catches of cetaceans in the Dutch pelagic trawl fishery are largely restricted to late-winter early-spring in an area along the continental slope southwest of Ireland. Available evidence indicates that annual variations in such incidents are large. Using combined mid-water trawl by-catch and dolphin stomach content data, the hypothesis is put forward that Atlantic white-sided dolphin (Lagenorhynchus acutus), normally a more oceanic species, may actively search for mackerel (Scomber scombrus) closer to shore in early-spring, at least in some years. Supporting data were from an observer program during 1992–94, which covered seven trips representing 5% of the annual effort in the fishery. Also over the period 1989–94, a total of 71 records of by-catch incidents were collected (involving a minimum of 312 individuals), of which 41 occured in 1994 (172 individuals). Approximately 90% of the incidents occurred late-winter early-spring, when both the mackerel and horse mackerel (Trachurus trachurus) pelagic fisheries were operating in the same area, southwest of Ireland. Incidence frequency peaked by late February and March, when mackerel is known to move into the area during its southward migration. The Atlantic white-sided dolphin was the main cetacean species in the by-catch (83% of all identified individuals). Other species recorded included long-finned pilot whale (Globicephala melas), short-beaked common dolphin (Delphinus delphis), bottlenose dolphin (Tursiops truncatus) and the white-beaked dolphin (Lagenorhynchus albirostris). The stomachs of 47 Atlantic white-sided dolphins, 11 common dolphins, two bottlenose dolphins and one white-beaked dolphin were examined. Fresh mackerel remains were found in nearly all white-sided dolphin stomachs, whereas fresh horse mackerel remains occured only in stomachs of bottlenose and common dolphins. Deep-water fish otolith incidents suggested that white-sided, common and bottlenose dolphin had completely different diets before moving to the southwest of Ireland.

Concentrations and patterns of organic contaminants in Atlantic white-sided dolphins ( Lagenorhynchus acutus) from Irish and Scottish coastal waters

Chlorobiphenyls (CBs) and organochlorine pesticides (OCPs) have been determined in the blubber of 17 Atlantic white-sided dolphins stranded at Killala Bay, Co Mayo, Ireland and five from the Scottish coast. The concentrations of the contaminants measured range from 773 to 63 400μg kg −1 for ∑CB and from 160 to 54 600 μg kg −1 for ∑DDT. The concentrations of the CBs and OCPs is highly dependent on the age, sex, reproductive state and nutritional condition of the animals in addition to the intake via the food web. Principal Components Analysis (PCA) has been used to study the variation of chemical patterns (data ratioed to CB 153). Immature animals (< 6 years), mature males and primogravid females, and lactating females could be distinguished on the basis of their contaminant patterns. This paper describes the different processes of bioaccumulation and metabolism of organochlorine contaminants (OCs) in this species.

Isolation of Brucella species from cetaceans, seals and an otter.

Brucella organisms which differed from the recognised species of the genus, were isolated from nine seals, eight cetaceans and one otter. A method is described for the isolation of Brucella species from sea mammals and the first isolations of Brucella species are recorded from an Atlantic white-sided dolphin (Lagenorhynchus acutus), two striped dolphins (Stenella coeuleoalba), a hooded seal (Cystophora cristata), a grey seal (Halichoerus grypus) and a European otter (Lutra lutra). There were differences in the culture media required for the primary isolation of the organisms and in their dependency on carbon dioxide, Subcutaneous lesions, when present, always yielded a confluent growth. The organisms were isolated from seven of 14 spleen samples and also from the mammary glands, uterus, testes and blood and the mandibular, gastric, iliac, sub-lumbar and colorectal lymph nodes.

Mycotic dermatitis in an Atlantic white-sided dolphin, a pygmy sperm whale, and two harbor seals

Mycotic dermatitis in an Atlantic white-sided dolphin, a pygmy sperm whale, and two harbor seals

Trace element concentrations in cetacean liver tissues archived in the National Marine Mammal Tissue Bank

The National Biomonitoring Specimen Bank (NBSB), a collaborative project of several U.S. government agencies, includes marine mammal tissues collected for the Alaska Marine Mammal Tissue Archival Project (AMMTAP) and the National Marine Mammal Tissue Bank (NMMTB). Tissues were collected from 139 animals representing 13 species of marine mammals from around the U.S. Recently, concentrations for up to 30 elements in liver tissues of nine long-finned pilot whales (Globicephala melas), six harbor porpoises (Phocoena phocoena), and four white-sided dolphins (Lagenorhynchus acutus) from the NMMTB were measured using instrumental neutron activation analysis. Results from analyses of these tissues are presented, compared with results for liver tissues from other marine mammals from the AMMTAP, and compared with published values.

Distribution and habitat partitioning by small odontocetes in the Gully, a submarine canyon on the Scotian Shelf

In this paper we examine the summer distribution of three species of small odontocetes in the highly productive waters in and near the Gully, a submarine canyon on the edge of the Scotian Shelf. Atlantic white-sided dolphins (Lagenorhynchus acutus) and common dolphins (Delphinus delphis) were not randomly distributed with respect to depth, sea-floor relief, month of sighting, or sea-surface temperature. Long-finned pilot whales (Globicephala melas) were not randomly distributed with respect to month or sea-surface temperature. These species used the Gully slightly differently, although there was overlap. White-sided dolphins were seen only in the core of the canyon, but were sighted at all temperatures, depths, and sea-floor reliefs and throughout the summer field season. Common dolphins had a modest range throughout the deeper waters and were not seen in the summer before July, when the water warms. Pilot whales ranged widely over the study area, preferring areas with fairly flat relief and were more common later in the summer, when the waters were warmer. It appears that white-sided and common dolphins partition the Gully temporally but not geographically.

Colpanar PCB and metal residues in dolphins from the U.S. Atlantic coast including Atlantic bottlenose obtained during the 1987/88 mass mortality

Bottlenose dolphins ( Tursiops truncatus ) collected during the 1987/88 mass mortality event along the Atlantic coast of the United States have been analyzed for coplanar PCBs #77, 105, 126 and 169 in blubber, and for the metals Hg, Pb, Cd, Mn, and Cr, and the non-metallic element Se in liver. Results have been compared to two reference species, common ( Delphinus delphis ) and white-sided ( Lagenorhynchus acutus ) dolphins. The three most toxic PCB congeners (#77, 126 and 169) contributed less than 1% of the total TCDD toxic equivalent concentration (TEC) calculated for all di-, mono- and non-ortho chlorine substituted PCBs in adult male animals. The total TEC for the four PCBs was approximately 4.5 times lower in adult female bottlenose than in male. The mean concentrations of Pb, Cd, Mn and Cr in adult male bottlenose dolphins were at or below the mean concentrations in the two reference species. The mean concentration of mercury was highest in adult female bottlenose dolphins. However, mercury concentrations in all animals studied correlated with selenium concentrations (r=0.86) at a 1:1 mole ratio, indicating that selenium may protect these animals from mercury toxicity.

MOVEMENTS AND DIVE BEHAVIOR OF A SATELLITE‐MONITORED ATLANTIC WHITE‐SIDED DOLPHIN (LAGENORHYNCHUS ACUTUS) IN THE GULF OF MAINE

Marine Mammal ScienceVolume 10, Issue 1 p. 116-121 MOVEMENTS AND DIVE BEHAVIOR OF A SATELLITE-MONITORED ATLANTIC WHITE-SIDED DOLPHIN (LAGENORHYNCHUS ACUTUS) IN THE GULF OF MAINE Bruce R. Mate, Bruce R. Mate Hatfield Marine Science Center, Oregon State University, Newport, Oregon 97365;Search for more papers by this authorKathleen M. Stafford, Kathleen M. Stafford Hatfield Marine Science Center, Oregon State University, Newport, Oregon 97365;Search for more papers by this authorRobert Nawojchik, Robert Nawojchik Mystic Marinelife Aquarium, Sea Research Foundation, Mystic, Connecticut 06335.Search for more papers by this authorJ. Lawrence Dunn, J. Lawrence Dunn Mystic Marinelife Aquarium, Sea Research Foundation, Mystic, Connecticut 06335.Search for more papers by this author Bruce R. Mate, Bruce R. Mate Hatfield Marine Science Center, Oregon State University, Newport, Oregon 97365;Search for more papers by this authorKathleen M. Stafford, Kathleen M. Stafford Hatfield Marine Science Center, Oregon State University, Newport, Oregon 97365;Search for more papers by this authorRobert Nawojchik, Robert Nawojchik Mystic Marinelife Aquarium, Sea Research Foundation, Mystic, Connecticut 06335.Search for more papers by this authorJ. Lawrence Dunn, J. Lawrence Dunn Mystic Marinelife Aquarium, Sea Research Foundation, Mystic, Connecticut 06335.Search for more papers by this author First published: January 1994 https://doi.org/10.1111/j.1748-7692.1994.tb00398.xCitations: 18AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Citing Literature Volume10, Issue1January 1994Pages 116-121 RelatedInformation

Intramuscular Sarcocystis in two beluga whales and an Atlantic white-sided dolphin from the St. Lawrence estuary, Quebec, Canada.

infection. VetParasitol 34: 159-163.7. Jeffrey M, O’Toole D, Smith T, Bridges AW: 1988, Immu-nocytochemistry of ovine sporozoan encephalitis and enceph-alomyelitis. J Comp Pathol 98:213-224.8. Jortner BS, Troutt HF, Collins T, Scarratt K: 1985, Lesions ofspinal cord parelaphostrongylosis in sheep. Sequential changesfollowing intramedullary larval migration, Vet Pathol 22:137-140.9. Leek RG, Fayer R: 1980, Amprolium for prophylaxis of ovine

PCB and DDT in blubber of cetaceans from the northeastern north Atlantic

Blubber from long-finned pilot whales, Atlantic white-sided dolphins and harbour porpoises caught off the Faroe Islands, and from fin whales, sei whales, and sperm whales from Iceland were analysed for organochlorine pollutants. Pollutant levels were positively correlated with increasing trophic level and inversely with body size. For any given species, the %DDE/ Σp, p′-DDT ratio increased with Σp, p′-DDT burden, probably reflecting increased detoxification activity of liver enzymes at higher contaminant concentrations. The % Σp, p′-DDT/PCB ratio decreased with increasing trophic level suggesting differential transfer rates of the two organochlorine groups through food webs. Because of the effect of transfer of organochlorines through gestation and lactation, Σp, p′-DDT and PCB levels, %DDE/ Σp, p′-DDT and % Σp, p′-DDT/PCB ratios were higher in males than in females.

Propulsive performance of three naturally occurring oscillating propeller planforms

A numerical method, the quasi-vortex-lattice method (QVLM), was applied to predict the propulsive performance of three naturally occurring oscillating propellers. These were cetacean flukes for a fin whale ( Balaenoptera physalus); white-sided dolphin ( Lagenorhynchus acutus); and white whale ( Delphinapterus leucas). The fin whale's flukes had the highest aspect ratio (6.1) and moderate sweep angle (31°); the white-sided dolphin's flukes had the highest sweep angle (47°) and lowest aspect ratio (2.7); and the white whale's flukes had moderate aspect ratio (3.3) and the lowest sweep angle (28°). In the numerical simulations, the planforms were assumed to be rigid both in chordwise and spanwise directions, and to be oscillating harmonically in an irrotational, incompressible fluid. Calculation and comparisons of propulsive efficiency and thrust coefficient vs advance ratio for each of the planforms were made in three cases: varied heave amplitude; different pitching axis positions; and varied angular amplitude of pitch.

Status of the Atlantic White-sided Dolphin, Lagenorhynchus acutus, in Canada

Status of the Atlantic White-sided Dolphin, Lagenorhynchus acutus, in Canada

Chemical residues in dolphins from the U.S. Atlantic coast including Atlantic bottlenose obtained during the 1987/88 mass mortality

Bottlenose dolphins ( Tursiops truncatus ) collected during the 1987/88 mass mortality event along the Atlantic coast of the United States have been analyzed for anthropogenic chemical contaminants. Average contaminant concentrations in adult males were higher than the average concentrations measured in adult females. Females could be divided into two groups by contaminant concentrations, one with low concentrations, and another with concentrations 4.4 times (PCBs) to 8.9 times (p,p′-DDE) greater. Contaminant concentrations in bottlenose were generally greater than the concentrations measured in either common ( Delphinus delphis ) or white-sided ( Lagenorhynchus acutus ) dolphins from the western North Atlantic Ocean. A subset of animals screened for unusual chemical contaminants showed that numerous polybrominated chemicals were present, including polybrominated biphenyls and diphenyl ethers not previously found in marine mammals from U.S. coastal waters.

Measurements of the bodies and flukes of several cetacean species

Specimens of nine species of cetacean were obtained through an entrapment and stranding network. These were: harbour porpoise (Phocoena phocoena); white-sided dolphin (Lagenorhynchus acutus); white-beaked dolphin (Lagenorhynchus albirostris); common dolphin (Delphinus delphis); white whale (Delphinapterus leucas); Sowerby9s beaked whale (Mesoplodon bidens); minke whale (Balaenoptera acutorostrata); fin whale (Balaenoptera physalus); and sperm whale (Physeter macrocephalus). Measurements of length, body girths, fluke-planform offsets and fluke-section offsets are presented for these species. Values of body volume, mass, wetted-surface area, prismatic and volumetric coefficients, fluke area, aspect ratio and sweep angles were estimated from these measurements. Parameters derived from these measurements lay within narrow ranges of values for all species. Variation over these ranges may indicate a correlation between species and their relative swimming performance.

THE DISTRIBUTION OF WHITE‐SIDED (LAGENORHYNCHUS ACUTUS) AND COMMON DOLPHINS (DELPHINUS DELPHIS) VS. ENVIRONMENTAL FEATURES OF THE CONTINENTAL SHELF OF THE NORTHEASTERN UNITED STATES

AbstractSightings of white‐sided (Lagenorhynchus acutus) and common dolphins (Delphinus delphis) from survey vessels operating on the continental shelf of the northeastern United States were recorded during spring and fall of six years. Distributions of these sightings were compared with sea surface temperature and salinity, and bottom topography. The apparent geographic distributions of the two species are complementary, although there is a broad overlap. White‐sided dolphins occurred primarily within the Gulf of Maine, but also on Georges Bank and in the mid‐Atlantic region. Common dolphins were abundant within a broad band paralleling the continental slope (100–200 m depth contour) from latitude 35°N to the northeast peak of Georges Bank. Sightings of this species were distributed primarily along the edge of the continental shelf south of 40°N in spring and north of this latitude in fall. Few sightings of common dolphins occurred in the Gulf of Maine.Although both species of dolphins were sighted more frequently in areas of high sea floor relief, white‐sided dolphins occurred in areas where sea surface temperatures and salinities are low while common dolphins were sighted in warmer, more saline waters. However, these environmental conditions may be only secondarily influencing dolphin distribution. Seasonal variation in sea surface temperature and salinity, and local nutrient upwelling in areas of high sea floor relief may affect preferred prey abundances, which in turn may affect dolphin distribution.

Microbiological characterization of three Atlantic whiteside dolphins (Lagenorhynchus acutus) from stranding through captivity with subsequent rehabilitation and release of one animal

AbstractThree live Atlantic whiteside dolphins (Lagenorhynchus acutus) were found beach‐stranded on Cape Cod in Massachusetts and were shipped to Mystic Marinelife Aquarium in Connecticut and held in captivity. Swab samples were collected routinely from the anus and blowhole of live animals and from internal organs at necropsy for microbial culture. Despite antibiotic therapy, one animal died on day 9 of captivity, and one died after 110 days. The survivor was released after 126 days of captivity. Klebsiella pneumoniae septicemia and staphylococcal pneumonia were likely responsible for the two deaths. A total of 26 different organisms (or groups of organisms) were recovered from the three dolphins, including several (e.g., Pseudomonas spp, Streptococcus faecalis Candida albicans, Proteus‐Morganella spp, Vibrio spp) that, in addition to the above organisms, could be potentially pathogenic for debilitated animals. Newly rescued marine mammals should be segregated from healthy animals if possible.

Post-mortem isolation of Vibrio alginolyticus from an Atlantic white-sided dolphin (Lagenorynchus acutus).

Post-mortem examination of a stranded Atlantic white-sided dolphin (lagenorynchus acutus) revealed congested lungs, sanguinous fluid in the peritoneal cavity, and an oral wound. Histopathologic findings were acute necrotizing hepatitis and acute focal bronchopneumonia. Vibrio alginolyticus was isolated from the blood and other organs.

Parasitic Mastitis in the Atlantic White-Sided Dolphin, Lagenorhynchus acutus, as a Probable Factor in Herd Productivity

In a survey of 30 female Atlantic white-sided dolphins, Lagenorhynchus acutus, taken from a mass stranded herd of approximately 150 animals, 47% were found to be infected with Crassicauda grampicola (Nematoda: Spiruridae) in the mammary glands. Associated lesions included verminous cysts, fibrosis, necrosis and inflammation, and destruction or replacement of normal parenchyma by nonsecretory tissue. The high incidence and severity of these lesions are viewed as potentially compromising the reproductive success of the herd. The life cycle of C. grampicola is discussed in relation to its presence in the mammary gland. Key words: cetacean, Atlantic white-sided dolphin, pathology, nematodes, mastitis, population, nutrition