An Inventory of Some Relatively Large Marine Mammals, Reptiles, and Fishes Sighted, Caught, By-Caught, or Stranded in the Mediterranean Coast of the Gaza Strip-Palestine

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.

Very low biodiversity of top predators—seabirds and marine mammals—in the high Arctic Ocean

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.

Fauna of marine mammals in China

Marine mammals, 41 species in total including 8 species of Mysticeti, 27 species of Odontoceti, 5 species of Pinnipedia and only 1 species of Sirenia have been known and recorded in China. According to the number of species of China marine mammals in each natural sea area, the Bohai Sea possesses only 9 species, accounting for the least, whereas the species in the South China Sea has the most abundant, existing 28 species. In comparison with Taiwan Province, 32 species distribute along the coast of mainland, and 30 species along the coast of Taiwan Province. Some species with rather strong Torrid Zone nature apparently represent the fauna of marine mammals in the southern sea area. Cold-warm species coming from the frost sea area represent the fauna of marine mammals in the northern sea area.

Summer distribution of marine mammals encountered along transects between South Africa and Antarctica during 2007 – 2012 in relation to oceanographic features

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.

Impacts of global climate change on birds and marine mammals in Antarctica

Birds and marine mammals in Antarctica, especially penguins and seals, are top consumers and critical elements of the Southem Ocean ecosystem. As a region undergoing rapid global change, new challenges will be posed to the survival of these vertebrates species. Global climate change causes many alterations, such as ocean temperature rise, altered sea ice distribution, and abnormal climate events along with effects of intensive human activities, such as fishing. These not only directly affect the spatiotemporal distributions and population dynamics of Antarctic birds and marine mammals but also indirectly influence them via modification of their food resources. At present, the impact of climate change on birds and marine mammals in the Antarctica is focusing on a number of species in a few areas. Response mechanisms of these species are still very limited and therefore require further long-term and continuous monitoring and research.

Adaptation of mammals to hypoxia

Oxygen plays a pivotal role in the metabolism and activities of mammals.However,oxygen is restricted in some environments-subterranean burrow systems or habitats at high altitude or deep in the ocean-and this could exert hypoxic stresses such as oxidative damage on organisms living in these environments.In order to cope with these stresses,organisms have evolved specific strategies to adapt to hypoxia,including changes in physiology,gene expression regulation,and genetic mutations.Here,we review how mammals have adapted to the three high-altitude plateaus of the world,the limited oxygen dissolved in deep water habitats,and underground tunnels,with the aim of better understanding the adaptation of mammals to hypoxia.

Seabird and marine mammal at-sea distribution in the western Bering Sea and along the eastern Kamtchatka Peninsula

Seabird and marine mammal at-sea distribution in the western Bering Sea and along the eastern Kamtchatka(Kamtsjatka)Peninsula was determined during 114 transect counts,lasting 30 min each,in September 2018.A total of 58000 seabirds were tallied,i.e.a mean value of 510 per count.The most abundant species was short-tailed shearwater:43250 individuals representing 74%of the total.Fulmar and kittiwake represented 13%and 8%of the total.Important geographical differences were noted,concerning both the number of seabird species and their abundance.The following species were tallied mainly in the northern zone(North of 60°N):fulmar(light morphs),short-tailed shearwater,Vega(herring)gull and horned puffin.In the southern zone,including Commander(Komandorski)Islands,observed species included fulmar(dark morphs),pelagic cormorant,glaucous-winged gull,red-legged kittiwake and black guillemot.The vast majority of the 100 cetaceans and 40 pinnipeds were tallied in the southern area,mainly porpoises,killer whale and humpback whale,and Largha(spotted)seal.

Major hotspots detected along the Scotia Ridge in autumn for southern right whales Eubalaena australis, Antarctic fur seals Arctocephalus gazella and Antarctic prions Pachyptila desolata

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.

Oxidative stress indicators in human and bottlenose dolphin leukocytes in response to a pro-inflammatory challenge

Marine mammals undergo cycles of tissue ischemia and reperfusion during the dive response.Reperfusion injury can result in oxidative tissue damage and the activation of a pro-inflammatory immune response.The risk of oxidative damage is reduced by antioxidants.Our hypothesis is that the reported higher antioxidant defenses within marine mammal tissues provide additional protection in situations that produce oxidative stress,like inflammation,in comparison to terrestrial mammal tissues.Leukocytes were isolated from the whole blood of Pacific bottlenose dolphins(Tursiops truncatus gilli)and humans(Homo sapiens)and were exposed to lipopolysaccharides(LPS,10μg/mL)in vitro to simulate a pro-inflammatory challenge.Oxidative stress indicators,including superoxide radical(O_(2)^(•−))production,activities of superoxide dismutase(SOD),catalase(CAT),glutathione peroxidase(GPx),glutathione reductase(GR),and glutathione S-transferase(GST),as well as oxidative protein damage,were quantified by spectrophotometry.Following 48 h under experimental conditions,bottlenose dolphin leukocytes produced 1.9 times more O_(2)^(•−)but displayed 2.0 times lower protein carbonyl concentrations compared to human leukocytes.Following 48 h under experimental conditions,bottlenose dolphin leukocytes displayed 7.9,2.0,11.1,and 3.3 times more activities of CAT,GPx,GR,and GST,respectively,compared to human leukocytes.These results suggest that,under cell culture conditions,the antioxidant defenses in bottlenose dolphin leukocytes provide additional protection against pro-inflammatory challenges in comparison to human leukocytes,likely as an adaptive advantage.

Detection of antibodies against Toxoplasma gondii in Mirounga leonina Linnaeus,1758(Pinnipedia,Phocidae)from Elephant Island

Objective:To investigate the presence of antibodies against Toxoplasma gondii(T.gondii)in Mirounga leonina(M.leonina)Linnaeus from Elephant Island,Antarctica.Methods:The animals were anesthetized,restrained,measured,weighed and had their blood collected by venipuncture of intervertebral lumbar epidural vein.Blood samples were collected from 102 individuals.Indirect hemagglutination and serum dilution at a proportion of 1:25 was used for specific immunoglobulin G anti-T.gondii detection.Results:Only one(0.98%)specimen,a newly weaned calf,was seropositive.Conclusions:This study is the highest serological survey for antibody detection against T.gondii in M.leonina.The results suggest a low level of exposure to T.gondii,probably due to the absence of felids in the study area.The seropositivity presented by the elephant seal may be related to the presence of oocysts in water or cysts in their preys.Despite being reported the presence of the parasite in fish and molluscs,there are no records of tissue cysts or oocysts in squid or fish of the diet of M.leonina.Thus,further parasitological studies focused on preys of elephant seals are needed for a better understanding of infection of M.leonina by T.gondii.