During the ARK-XXIII/3 expedition of icebreaking RV Polarstern in the high Arctic Ocean(partim north of 73°N)from 25 August to 10 October 2008,550 transect counts lasting 30 min were devoted to seabird and marine...During the ARK-XXIII/3 expedition of icebreaking RV Polarstern in the high Arctic Ocean(partim north of 73°N)from 25 August to 10 October 2008,550 transect counts lasting 30 min were devoted to seabird and marine mammal counts from the bridge.In the whole area,the three most numerous species,kittiwake Rissa tridactyla,fulmar Fulmarus glacialis and Brünnich’s guillemot Uria lomvia represented 90%of the total of 12000 individuals registered,followed by ivory gull Pagophila eburnea,black guillemot Cepphus grylle and Ross’s gull Rodostethia rosea.Four geographical zones were recognized on the basis of number of species and density.Both were especially low in the deeper areas(mean depth of 3000 m),both ice-free and heavily ice-covered:0.3 birds per 30 min count belonging to three and four species respectively.The most numerous species was kittiwake with 0.25 per count(50 individuals)in the ice-covered area.Pinniped numbers were very low as well,the most numerous of the four species tallied being 20 harp seals Phoca groenlandica and 10 ringed seal Pusa hispida.Seven polar bears Ursus maritimus were encountered.These observations were basically confirmed during 12 helicopter flights lasting one hour each with very low numbers:50 kittiwakes and 13 harp seals,almost none in the ice-covered deep zone.A comparison between data obtained from ship and from helicopter seems however to reflect the importance of seabird followers including for long distances.The only cetaceans were two adult belugas Delphinapterus leucas tallied from helicopter.展开更多
The Mediterranean Sea is home to an interesting biodiversity. The current cumulative and descriptive study aims to enumerate some relatively large marine mammals, reptiles, and fishes that have been spotted, caught, b...The Mediterranean Sea is home to an interesting biodiversity. The current cumulative and descriptive study aims to enumerate some relatively large marine mammals, reptiles, and fishes that have been spotted, caught, by-caught, or stranded on the coast of the Gaza Strip, Palestine, which extends about 42 km along the Mediterranean Sea. This 20-year study from 2003 to 2022 relied much on frequent field visits, meetings, and discussions with stakeholders, following local media sites and social media pages, and photography. The study recorded at least 26 giants or relatively large marine organisms on the Mediterranean coast of the Gaza Strip, Palestine. Certainly, the coming years may bring other marine organisms of relatively large sizes. Marine mammals included three species of cetaceans with the Fin Whale (Balaenoptera physalus) being the largest mammal and even the largest animal ever recorded in this study. Marine reptiles included three species of sea turtles, the largest of which is the Leatherback Sea Turtle (Dermochelys coriacea), which is in fact the world’s largest sea turtle. The bony fishes were represented by ten species, the largest of which was the Ocean Sunfish (Mola mola), which is the largest bony fish in the world. The cartilaginous fishes included ten species with the largest specimens encountered were the Shortfin Shark (Isurus oxyrinchus), Bluntnose Sixgill Shark (Hexanchus griseus), Scalloped Hammerhead Shark (Sphyrna lewini), and Giant Devil Ray (Mobula mobular). Seabirds were not included in the study. The Alexandria Pompano (Alectis alexandrinus) and the Silver-Cheeked Toadfish (Lagocephalus sceleratus), which are bony fishes, appear to be the relatively smallest marine organisms recorded here. In conclusion, the role of the various parties must be coordinated to ensure the sustainability of human activities and their compatibility with the task of conserving local marine biota, including the gigantic or relatively large ones.展开更多
The at-sea summertime distribution of marine mammals between South Africa and Antarctica was determined along eight transects surveyed between December 2007 and January 2012. During 1930 30-minute transect counts, 139...The at-sea summertime distribution of marine mammals between South Africa and Antarctica was determined along eight transects surveyed between December 2007 and January 2012. During 1930 30-minute transect counts, 1390 marine mammal individuals were attributed to 19 species： eight toothed whales （Odontoceti）, six pinnipeds, and five baleen whales （Mysticeti）. An additional two toothed-whale species were encountered ＇out of effort＇. The four most numerous species accounted for 85% of the total number of individuals encountered： crabeater seal （Lobodon carcinophagus）, humpback whale （Megaptera novaeangliae）, Antarctic Minke whale （Balaenoptera bonaerensis） and fin whale （B. physalus）. The distribution of these species was related to oceanographic features, such as water masses and fronts, pack ice and ice edge： These differences were statistically highly significant. Biodiversity was compared with other polar marine ecosystems.展开更多
We investigated the role of hydrological features, such as water masses, fronts, eddies, and sea ice, in affecting the distribution of upper trophic level species in the Scotia Sea region during autumn. On board RV Po...We investigated the role of hydrological features, such as water masses, fronts, eddies, and sea ice, in affecting the distribution of upper trophic level species in the Scotia Sea region during autumn. On board RV Polarstern, we performed 365 30-min strip transects recording seabirds and marine mammals along the North Scotia Ridge and the South Sandwich Trench in March--April 2013. Among the 7 identified cetacean species recorded, the humpback whale Megaptera novaeangliae was the most abundant baleen whale （40 individuals）, and noteworthy were sightings of six southern right whales Eubalaena australis. Pinnipeds （3 species, 1650 individuals） were dominated by Antarctic fur seal Arctocephalus gazella （99%）, and seabirds （36 species, 18900 individuals） by Antarctic prion Pachyptila desolata （-50%）. The distribution of these top predators was highly patchy with the majority of observations concentrated in a few counts. This heterogeneity is likely a result of prey availability, and we discuss how hydrological features may have caused the patchiness.展开更多
文摘During the ARK-XXIII/3 expedition of icebreaking RV Polarstern in the high Arctic Ocean(partim north of 73°N)from 25 August to 10 October 2008,550 transect counts lasting 30 min were devoted to seabird and marine mammal counts from the bridge.In the whole area,the three most numerous species,kittiwake Rissa tridactyla,fulmar Fulmarus glacialis and Brünnich’s guillemot Uria lomvia represented 90%of the total of 12000 individuals registered,followed by ivory gull Pagophila eburnea,black guillemot Cepphus grylle and Ross’s gull Rodostethia rosea.Four geographical zones were recognized on the basis of number of species and density.Both were especially low in the deeper areas(mean depth of 3000 m),both ice-free and heavily ice-covered:0.3 birds per 30 min count belonging to three and four species respectively.The most numerous species was kittiwake with 0.25 per count(50 individuals)in the ice-covered area.Pinniped numbers were very low as well,the most numerous of the four species tallied being 20 harp seals Phoca groenlandica and 10 ringed seal Pusa hispida.Seven polar bears Ursus maritimus were encountered.These observations were basically confirmed during 12 helicopter flights lasting one hour each with very low numbers:50 kittiwakes and 13 harp seals,almost none in the ice-covered deep zone.A comparison between data obtained from ship and from helicopter seems however to reflect the importance of seabird followers including for long distances.The only cetaceans were two adult belugas Delphinapterus leucas tallied from helicopter.
文摘The Mediterranean Sea is home to an interesting biodiversity. The current cumulative and descriptive study aims to enumerate some relatively large marine mammals, reptiles, and fishes that have been spotted, caught, by-caught, or stranded on the coast of the Gaza Strip, Palestine, which extends about 42 km along the Mediterranean Sea. This 20-year study from 2003 to 2022 relied much on frequent field visits, meetings, and discussions with stakeholders, following local media sites and social media pages, and photography. The study recorded at least 26 giants or relatively large marine organisms on the Mediterranean coast of the Gaza Strip, Palestine. Certainly, the coming years may bring other marine organisms of relatively large sizes. Marine mammals included three species of cetaceans with the Fin Whale (Balaenoptera physalus) being the largest mammal and even the largest animal ever recorded in this study. Marine reptiles included three species of sea turtles, the largest of which is the Leatherback Sea Turtle (Dermochelys coriacea), which is in fact the world’s largest sea turtle. The bony fishes were represented by ten species, the largest of which was the Ocean Sunfish (Mola mola), which is the largest bony fish in the world. The cartilaginous fishes included ten species with the largest specimens encountered were the Shortfin Shark (Isurus oxyrinchus), Bluntnose Sixgill Shark (Hexanchus griseus), Scalloped Hammerhead Shark (Sphyrna lewini), and Giant Devil Ray (Mobula mobular). Seabirds were not included in the study. The Alexandria Pompano (Alectis alexandrinus) and the Silver-Cheeked Toadfish (Lagocephalus sceleratus), which are bony fishes, appear to be the relatively smallest marine organisms recorded here. In conclusion, the role of the various parties must be coordinated to ensure the sustainability of human activities and their compatibility with the task of conserving local marine biota, including the gigantic or relatively large ones.
文摘The at-sea summertime distribution of marine mammals between South Africa and Antarctica was determined along eight transects surveyed between December 2007 and January 2012. During 1930 30-minute transect counts, 1390 marine mammal individuals were attributed to 19 species： eight toothed whales （Odontoceti）, six pinnipeds, and five baleen whales （Mysticeti）. An additional two toothed-whale species were encountered ＇out of effort＇. The four most numerous species accounted for 85% of the total number of individuals encountered： crabeater seal （Lobodon carcinophagus）, humpback whale （Megaptera novaeangliae）, Antarctic Minke whale （Balaenoptera bonaerensis） and fin whale （B. physalus）. The distribution of these species was related to oceanographic features, such as water masses and fronts, pack ice and ice edge： These differences were statistically highly significant. Biodiversity was compared with other polar marine ecosystems.
文摘We investigated the role of hydrological features, such as water masses, fronts, eddies, and sea ice, in affecting the distribution of upper trophic level species in the Scotia Sea region during autumn. On board RV Polarstern, we performed 365 30-min strip transects recording seabirds and marine mammals along the North Scotia Ridge and the South Sandwich Trench in March--April 2013. Among the 7 identified cetacean species recorded, the humpback whale Megaptera novaeangliae was the most abundant baleen whale （40 individuals）, and noteworthy were sightings of six southern right whales Eubalaena australis. Pinnipeds （3 species, 1650 individuals） were dominated by Antarctic fur seal Arctocephalus gazella （99%）, and seabirds （36 species, 18900 individuals） by Antarctic prion Pachyptila desolata （-50%）. The distribution of these top predators was highly patchy with the majority of observations concentrated in a few counts. This heterogeneity is likely a result of prey availability, and we discuss how hydrological features may have caused the patchiness.
