Seasonal variation of striped dolphins, fin- and sperm whales' abundance in the Ligurian Sea (Mediterranean Sea)

2007 ◽  
Vol 87 (1) ◽  
pp. 345-352 ◽  
Author(s):  
Sophie Laran ◽  
Violaine Drouot-Dulau
Keyword(s):  
Relative Abundance ◽  
Sperm Whale ◽  
Line Transect ◽  
Physeter Macrocephalus ◽  
Monthly Basis ◽  
Ligurian Sea ◽  
Stenella Coeruleoalba ◽  
Abundance Indices ◽  
Fin Whales ◽  
Acoustic Sampling

In order to investigate seasonal changes in cetacean relative abundance, a series of surveys were conducted between the French mainland and Corsica. From February 2001 to February 2004, thirty similar transects were conducted monthly, using the same dedicated boat and a consistent sampling protocol, including visual observation and passive acoustic sampling. A total effort of 5759 km was sampled, conducted at the same speed and in good sighting conditions. Relative abundances of striped dolphins (Stenella coeruleoalba) and fin whales (Balaenoptera physalus) were determined using standard line-transect methodology. The relative abundance of striped dolphins peaked in May and September (>1.3×10-2 ind.km-1), while a consistent minimum value (<0.6×10-2 ind.km-1) was obtained from December to April. A maximum relative abundance of fin whales occurred in August with 5.6×10-2 ind.km-1 and decreased to almost zero from November to January. For sperm whale (Physeter macrocephalus), a long diver species, frequency and abundance indices were determined using acoustic sampling. The highest acoustic relative abundance was observed from August to October, with more than 2×10-2 ind.km-1. Environmental parameters (sea surface temperature and chlorophyll) were computed for the sampling area from remote sensing imagery and pooled on a monthly basis, to correlate with relative abundance indices of the three species.

Summer distribution and relative abundance of cetacean populations off north-west Scotland

2003 ◽  
Vol 83 (5) ◽  
pp. 1187-1192 ◽  
Author(s):  
K. Macleod ◽  
M.P. Simmonds ◽  
E. Murray
Keyword(s):  
Relative Abundance ◽  
Sperm Whale ◽  
Abundant Species ◽  
Line Transect ◽  
Migration Route ◽  
Common Dolphin ◽  
Physeter Macrocephalus ◽  
Pilot Whale ◽  
North West ◽  
Line Transect Survey

A line transect survey was conducted in July/August 1998 to investigate the distribution and abundance of cetaceans off north-west Scotland. Over 2156.5 km of survey effort, 304 sightings were recorded of which 184 were identified to species. Nine species were identified: Atlantic white-sided dolphin Lagenorhynchus acutus, fin whale Balaenoptera physalus, sei whale Balaenoptera borealis, long-finned pilot whale Globicephala melas, sperm whale Physeter macrocephalus, common dolphin Delphinus delphis, harbour porpoise Phocoena phocoena, white beaked dolphin Lagenorhynchus albirostris and Risso's dolphin Grampus griseus. The Atlantic white-sided dolphin was the most relatively abundant species. The relative abundance of large whales and dolphins was greatest in the Faroe–Shetland Channel. The continental slopes of this area are undergoing development by oil industries and concerns have been raised about the potential impacts of these activities on cetaceans. These waters are used year-round by cetaceans and provide feeding and breeding grounds and are a migration route for large whales.

Biological consequences of global warming: does sea surface temperature affect cetacean distribution in the western Ligurian Sea?

2008 ◽  
Vol 88 (6) ◽  
pp. 1145-1152 ◽  
Author(s):  
A. Azzellino ◽  
S.A. Gaspari ◽  
S. Airoldi ◽  
C. Lanfredi
Keyword(s):  
Surface Temperature ◽  
Sea Surface Temperature ◽  
Global Climate ◽  
Sperm Whale ◽  
Sea Surface ◽  
Distribution Data ◽  
Physeter Macrocephalus ◽  
Ligurian Sea ◽  
Stenella Coeruleoalba ◽  
Cetacean Distribution

The aim of this study was to assess if sea surface temperature does affect cetacean distribution in the western Ligurian Sea. Relationships with temperature were investigated for: striped dolphin (Stenella coeruleoalba), fin whale (Balaenoptera physalus) and sperm whale (Physeter macrocephalus). Remotely sensed sea surface temperature (SST) data were studied. A series of 20 monthly images (i.e. June to September monthly images from 1996 to 2000) was considered. Concurrently, distribution data collected during shipboard summer surveys, and covering an area of about 20,000 km2 in the western Ligurian Sea, were analysed. The relationship between the three species presence and SST was investigated by using a grid of 3 × 3 nautical mile cell units. For every cell the SST mean, standard deviation, coefficient of variance and the deviation from the monthly average were calculated. Finally, binary logistic regression functions allowed to assess significant (P < 0.05) relationships with temperature in these species. These logistic models, were able to predict 60–78% of the species presence(1)/absence(0) cells, and suggest the need for further investigations spanning longer time periods to assess how the global climate change has been changing and will change in the future cetacean distribution in the western Ligurian Sea.

Comparison of odontocete populations of the Marquesas and Society Islands (French Polynesia)

2008 ◽  
Vol 89 (5) ◽  
pp. 931-941 ◽  
Author(s):  
Alexandre Gannier
Keyword(s):  
Relative Abundance ◽  
Bottlenose Dolphin ◽  
Bottlenose Dolphins ◽  
Sperm Whale ◽  
French Polynesia ◽  
Society Islands ◽  
Spotted Dolphin ◽  
Abundance Indices ◽  
Beaked Whales ◽  
Using Data

Small boat surveys were organized to study cetaceans of the Marquesas (9°S and 140°W) and the Society Islands (17°S and 150°W) in French Polynesia. Prospecting took place from 12–15 m sailboats, between 1996 and 2001 with systematic visual searching. Boats moved according to sea conditions, at a mean speed of 10 km/h. Effective effort of 4856 km in the Marquesas and 10,127 km in the Societies were logged. Relative abundance indices were processed for odontocetes using data obtained with Beaufort 4 or less. In the Marquesas, 153 on-effort sightings were obtained on 10 delphinids species including the spotted dolphin, spinner dolphin, bottlenose dolphin, melon-headed whale and rough-toothed dolphin. In the Societies, 153 sightings of 12 odontocetes included delphinids (spinner, rough-toothed and bottlenose dolphins, short-finned pilot and melon-headed whales, Fraser's dolphin, Risso's dolphin and pygmy killer whale) and two species of beaked whales, the sperm whale and dwarf sperm whale. Relative abundance indices were higher in the Marquesas than in the Societies both inshore (0.93 ind/km2 against 0.36 ind/km2) and offshore (0.28 ind/km2 against 0.14 ind/km2). Differences in remote-sensed primary production were equally important, the Marquesas waters featuring an annual average of 409 mgC.m−2 · day−1 and the Societies of only 171 mgC · m−2 · day−1. The presence of a narrow shelf around the Marquesas also accounted for differences in odontocete populations, in particular the delphinids.

scholarly journals Wild whale faecal samples as a proxy of anthropogenic impact

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Marianna Marangi ◽  
Sabina Airoldi ◽  
Luciano Beneduce ◽  
Claudio Zaccone
Keyword(s):  
Heavy Metals ◽  
Mediterranean Sea ◽  
Limit Of Detection ◽  
Sperm Whale ◽  
Anthropogenic Activity ◽  
Physeter Macrocephalus ◽  
Sperm Whales ◽  
Faecal Samples ◽  
Fin Whales ◽  
Free Ranging

AbstractThe occurrence of protozoan parasite, bacterial communities, organic pollutants and heavy metals was investigated in free-ranging species of fin (Balaenoptera physalus, n. 2) and sperm (Physeter macrocephalus, n. 2) whales from the Pelagos Sanctuary, Corsican-Ligurian Provencal Basin (Northern-Western Mediterranean Sea). Out of four faecal samples investigated, two from fin whales and one from sperm whale were found positive to Blastocystis sp. A higher number of sequences related to Synergistetes and Spirochaetae were found in sperm whales if compared with fin whales. Moreover, As, Co and Hg were found exclusively in sperm whale faecal samples, while Pb was found only in fin whale faecal samples. The concentration of both PAH and PCB was always below the limit of detection. This is the first report in which the presence of these opportunistic pathogens, bacteria and chemical pollutants have been investigated in faecal samples of free-ranging whale species and the first record of Blastocystis in fin and sperm whales. Thus, this study may provide baseline data on new anthropozoonotic parasite, bacterial records and heavy metals in free-ranging fin and sperm whales, probably as a result of an increasing anthropogenic activity. This survey calls for more integrated research to perform regular monitoring programs supported by national and/or international authorities responsible for preservation of these still vulnerable and threatened whale species in the Mediterranean Sea.

scholarly journals A note on concentrations of metals in cetaceans from southern Africa

1999 ◽  
pp. 177-194
Author(s):  
John Henry
Keyword(s):  
Sperm Whale ◽  
Common Dolphin ◽  
Physeter Macrocephalus ◽  
Cetacean Species ◽  
Stenella Coeruleoalba ◽  
Right Whales ◽  
Beaked Whales ◽  
Common Dolphins ◽  
Hourglass Dolphin ◽  
Pygmy Sperm Whale

Concentrations of zinc, copper, cadmium, mercury and lead were measured by atomic absorption spectrophotometry in samples of the brain, kidney , liver and muscle tissue from 178 individuals of 323 different cetacean species (4 right whales - Eubalaena australis, 2 pygmy right whales - Caperea marginara, 3 minke whales - Balaenoptera acutorostrata, 3 Bryde's whales - B. edeni, 1 humpback whale - Megaptera novaeangliae, 1 sperm whale - Physeter macrocephalus, 11 pygmy sperm whale - Kogia breviceps, 6 dwarf sperm whales - K. simus, 1 southern bottlenose whale - Hyperoodon planifrons, 1 Cuvier's beaked whale - Ziphius cavirostris, 9 Blainville's beaked whales - Mesoplodon densirostris, 5 strap-tooth whales - M. layardii, 2 True's beaked whales - M. mirus, 3 long-finned pilot whales - Globicephala me/as, 30 Risso's dolphins - Grampus griseus, 12 bottlenose dolphins - Tursiops truncatus, 5 striped dolphins - Stenella coeruleoalba, 1 pantropical spotted dolphin - S. attenuata, 1 hump-backed dolphin - Sousa chinensis, 21 dusky dolphins - Lagenorhynchus obscurus, 1 hourglass dolphin - L. cruciger, 12 Heaviside's dolphins - Cephalorhynchus heavisidii and 43 common dolphins - Delphinus delphis). All but the hourglass dolphin were strandings or animals taken incidental to fishing operations or under scientific permit in coastal waters of South Africa or Namibia. Highest concentrations of Zn, Cu and Hg were generally found in the liver and of Cd in the kidney. Comparisons of animals pre-and post puberty indicated accumulation of hepatic mercury in the pygmy sperm whale, Risso's dolphin, dusky dolphin and common dolphin. Loss of a metal (zinc) after puberty was only shown in the common dolphin. No individual analyses exceeded proposed (human) tolerance limits for hepatic mercury and hepatic or renal cadmium

scholarly journals Summer Distribution, Relative Abundance and Encounter Rates of Cetaceans in the Mediterranean Waters off Southern Italy (Western Ionian Sea and Southern Tyrrhenian Sea)

2015 ◽  
Vol 16 (3) ◽  
pp. 613 ◽  
Author(s):  
R. SANTORO ◽  
E. SPERONE ◽  
M. L. TRINGALI ◽  
G. PELLEGRINO ◽  
G. GIGLIO ◽  
...  
Keyword(s):  
Large Scale ◽  
Southern Italy ◽  
Anthropogenic Factors ◽  
Line Transect ◽  
Tyrrhenian Sea ◽  
Physeter Macrocephalus ◽  
Cetacean Species ◽  
Stenella Coeruleoalba ◽  
The Mediterranean ◽  
Steno Bredanensis

In summer 2010 and summer 2011, weekly cetacean surveys were undertaken in “passing mode”, using ferries as platform of opportunity, along the “fixed line transect” between Catania and Civitavecchia (Southern Italy). Of the 20 species of cetaceans confirmed for the Mediterranean sea, 8 were sighted within the survey period: 7 species represented by Mediterranean subpopulations (Balaenoptera physalus, Physeter macrocephalus, Stenella coeruleoalba, Delphinus delphis, Grampus griseus, Tursiops truncatus and Ziphius cavirostris) and one considered visitor (Steno bredanensis). We had a total of 220 sightings during the 2010 and a total of 240 sightings in the 2011. The most frequent species was S. coeruleoalba. By the comparison of the data from the two sampling seasons, a significant increase of D. delphis sightings and a decrease of sightings of B. physalus and P. macrocephalus was observed from 2010 to 2011. While all the other species were observed in both sampling seasons, Z. cavirostris and Steno bredanensis were observed only during 2011. The presence of mixed groups of odontocetes was documented too: we sighted groups composed by S. coeruleoalba and D. delphis, by S. coeruleoalba and T. truncatus, and by S. coeruleoalba and G. griseus. The results of this research add useful information on cetacean species in a very poorly known area and highlight the need to standardize large scale and long term monitoring programs in order to detect variation in presence, abundance and distribution of cetaceans populations and understand the effect of anthropogenic factors.

scholarly journals Combined line-transect and cue-count estimate of sperm whale abundance in the North Atlantic, from Icelandic NASS-2001 shipboard survey

2009 ◽  
Vol 7 ◽  
pp. 73
Author(s):  
Thorvaldur Gunnlaugsson ◽  
Gisli A Víkingsson ◽  
Daniel G Pike
Keyword(s):  
North Atlantic ◽  
Sperm Whale ◽  
Line Transect ◽  
Physeter Macrocephalus ◽  
Preliminary Estimate ◽  
Sperm Whales ◽  
Deep Dive ◽  
The North ◽  
Surface Time ◽  
Track Line

Sperm whales (Physeter macrocephalus) pose a particular problem to shipboard surveys as they dive for extended periods and are therefore likely to be missed (not available) even if they are right under the track line. To address these problems the NAMMCO planning committee for the NASS 2001 survey drew up guidelines to be followed when sperm whales were sighted. This required every deep dive to be recorded and considered to be a cue, from which a cue-count estimate is calculated if the cue rate is known. For those whales that did not dive before coming abeam, a conventional line-transect estimate is calculated, which gives an instantaneous surface estimate from which a total estimate can be obtained if the proportion of the time spent at the surface is known. These estimates are compared and combined. Precise dive cycle information is missing for the mostly single all male sperm whales in this area but a preliminary estimate of 11,185 (cv 0.34) is obtained for the surveyed area with an assumed surface time of 20% and two deep dives per hour.

scholarly journals Cetacean strandings along the German North Sea coastline 1604–2017

2021 ◽  
pp. 1-20
Author(s):  
Carl Christian Kinze ◽  
Richard Czeck ◽  
Helena Herr ◽  
Ursula Siebert
Keyword(s):  
North Sea ◽  
Native Species ◽  
Sperm Whale ◽  
Beluga Whale ◽  
Delphinapterus Leucas ◽  
Common Dolphin ◽  
Physeter Macrocephalus ◽  
Pilot Whale ◽  
Stenella Coeruleoalba ◽  
Fin Whale

Abstract The occurrence of 19 cetacean species along the German North Sea coastline as well as the lower reaches of the major rivers discharging into the German Bight is reviewed for the period 1604–2017 based on records of dead animals, either stranded dead or put to death. The harbour porpoise (Phocoena phocoena) is considered the most abundant and only native species in German coastal and riverine waters. Based on written sources its presence can be traced back to at least 1651, although with statistical data only available from 1990. Finds of further 18 species have been documented: white-beaked dolphin (Lagenorhynchus albirostris), bottlenose dolphin (Tursiops truncatus), Atlantic white-sided dolphin (Lagenorhynchus acutus), common dolphin (Delphinus delphis), striped dolphin (Stenella coeruleoalba), Risso's dolphin (Grampus griseus), long-finned pilot whale (Globicephala melas), killer whale (Orcinus orca), beluga whale (Delphinapterus leucas), narwhal (Monodon monoceros), Sowerby's beaked whale (Mesoplodon bidens), northern bottlenose whale (Hyperoodon ampullatus), sperm whale (Physeter macrocephalus), minke whale (Balaenoptera acutorostrata), sei whale (Balaenoptera borealis), fin whale (Balaenoptera physalus), blue whale (Balaenoptera musculus) and humpback whale (Megaptera novaeangliae). This review corrects several false species assignments earlier introduced in literature based on incorrect scientific or ambiguous German vernacular names and recovers lost records of beluga whale, northern bottlenose whale, sperm whale and fin whale.

Stomach contents of a sperm whale (Physeter macrocephalus) stranded in Italy (Ligurian Sea, north-western Mediterranean)

2013 ◽  
Vol 94 (6) ◽  
pp. 1087-1091 ◽  
Author(s):  
Fulvio Garibaldi ◽  
Michela Podestà
Keyword(s):  
Stomach Contents ◽  
Sperm Whale ◽  
Western Mediterranean ◽  
Physeter Macrocephalus ◽  
Sperm Whales ◽  
Western Basin ◽  
Ligurian Sea ◽  
Beak Size ◽  
Species Specific ◽  
Available Information

The stomach contents of a male sperm whale, Physeter macrocephalus, stranded on Forte dei Marmi beach (Italy, Ligurian Sea) were examined. Food items consisted exclusively of cephalopod hard parts: 233 upper and 291 lower beaks and one fish eye lens. The majority of the identified cephalopod beaks belonged to Histioteuthis bonnellii, but a few beaks of Galiteuthis armata and Octopoteuthis sp. were also found. A new beak size–cephalopod size regression was created for H. bonnellii with specimens caught in the study area. Reconstructed prey weight for the species was much higher when applying this new regression instead of Clarke's, highlighting the need for area- and species-specific regressions for dietary studies. Our analysis represents the second report on the stomach contents of sperm whales from the Mediterranean and the first available information for the Western basin.

scholarly journals Estimated Abundances of Cetacean Species in the Northeast Atlantic from Two Multiyear Surveys Conducted by Norwegian Vessels between 2002–2013

2020 ◽  
Vol 11 ◽  
Author(s):  
Deanna Leonard ◽  
Nils Øien
Keyword(s):  
Barents Sea ◽  
Distance Sampling ◽  
Humpback Whales ◽  
Line Transect ◽  
Physeter Macrocephalus ◽  
Sperm Whales ◽  
Independent Observer ◽  
Northeast Atlantic ◽  
Management Procedure ◽  
Fin Whales

Two shipboard line-transect surveys of the Northeast Atlantic were conducted between 2002–2007 and 2008–2013 to meet the ongoing requirements of the Revised Management Procedure (RMP) for common minke whales (Balaenoptera acutorostrata acutorostrata) developed by the International Whaling Commission’s Scientific Committee. Here we present estimated abundances for non-target species for which there were sufficient sightings, including fin whales (Balaenoptera physalus), humpback whales (Megaptera novaeangliae), sperm whales (Physeter macrocephalus), killer whales (Orcinus orca), harbour porpoises (Phocoena phocoena), and dolphins of genus Lagenorhynchus. The 2 surveys were conducted using a multiyear mosaic survey design with 2 independent observer platforms operating in passing mode, each with 2 observers. The abundances of Lagenorhynchus spp. from the 2002–2007 survey were estimated using single-platform standard distance sampling methods because of uncertainty in identifying duplicate sightings. All other estimates were derived using mark-recapture distance sampling techniques applied to a combined-platform dataset of observations, correcting for perception bias. Most notably, we find that the abundance of humpback whales, similar in both survey periods, has doubled since the 1990s with the most striking changes occurring in the Barents Sea. We also show that the pattern in distribution and abundance of fin whales and sperm whales is consistent with our earlier surveys, and that abundances of small odontocete species, which were not estimated in earlier surveys, show stable distributions with some variation in their estimates. Our estimates do not account for distributional shifts between years or correct for biases due to availability or responsive movement.

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