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

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Advances in Polar Science 2019年第4期30卷 375-381页

作者： claude r.joiris Laboratory for Polar Ecology(PolE) Conservation Biology Unit Royal Belgian Institute for Natural Sciences(RBINS)

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 *** 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 *** geographical zones were recognized on the basis of number of species and *** 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 *** most numerous species was kittiwake with 0.25 per count(50 individuals)in the ice-covered *** 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 *** polar bears Ursus maritimus were *** 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 *** only cetaceans were two adult belugas Delphinapterus leucas tallied from helicopter.

关键词： seabirds marine mammals at-sea distribution high Arctic Ocean

Considerable increase in bowhead,blue,humpback and fin whales numbers in the Greenland Sea and Fram Strait between 1979 and 2014

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Advances in Polar Science 2016年第2期27卷 117-125页

作者： claude r.joiris Laboratory for Polar Ecology(PolE) 1367 RamilliesBelgium Conservation Biology Unit Royal Belgian Institute for Natural Sciences1000 BrusselsBelgium

In the frame of our long-term study of cetacean abundance and distribution in polar marine ecosystems begun in 1979, a drastic increase in the bowbead Balaena mysticetus North Atlantic ＂stock＂ was observed from 2005 on, by a factor 30 and more： from 0.0002 per count between 1979 and 2003 （one individual, n=5430 cotmts） to 0.06 per count from 2005 to 2014 （34 individuals, n=6000 counts）; the most significant part of the increase occurred from 2007 on. Other large whale species （Mysticeti） showed a similar pattern, mainly blue Balaenoptera musculus, humpback Megaptera novaeangliae and fin whales Balaenoptera physalus. This large and abrupt increase cannot logically be due to population growth, nor to survival of a hidden ＂relic＂ population, nor to a changing geographical distribution within the European Arctic, taking into account the importance of the coverage during this study. Our interpretation is that individuals passed through the Northwest and/or Northeast Passages from the larger Pacific stock into the almost depleted North Atlantic populations coinciding with a period of very low ice coverage -- at the time the lowest ever recorded. In contrast, no clear evolution was detected neither for sperm whale Physeter macrocephalus nor for Minke whale Balaenoptera acusrostrata.

关键词： Greenland Sea Fram Strait bowhead whale blue whale humpback whale fin whale

Hotspots of seabirds and marine mammals between New Zealand and the ross Gyre:importance of hydrographic features

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Advances in Polar Science 2018年第4期29卷 254-261页

作者： claude r.joiris Grant r.W.HUMPHrIES Laboratory for Polar Ecology(PolE) 26130 Saint-RestitutFrance Conservation Biology Unit Royal Belgian Institute for Natural Sciences(RBINS)1000 BrusselsBelgium Black Bawks Data Science Fort Augustus PH32 4DRUnited Kingdom

This article is part of our long-term study on the quantitative at-sea distribution of the marine "upper trophic levels"—seabirds and marine mammals—in polar ecosystems, aiming at quantifying the factors influencing their distribution as well as detecting possible spatial and temporal changes, with special attention to hydrography and to global climate changes. During an expedition of icebreaking rV Polarstern in February 2010, along the North–South transect between New Zealand and the ross Gyre, off the ross Sea, 3200 seabirds belonging to 22 identified pelagic species were recorded during 338 half-hour transect counts. Four major hotspots were identified. These were in Sub-tropical Water off New Zealand(up to 300 birds per count), and at the main Southern Ocean fronts: the Sub-Antarctic Front(up to 240 per count), the Antarctic Front(up to 150 per count) and the Polar Front(up to 200 per count), representing the vast majority of recorded seabirds. The most numerous species in the three frontal zones were: prions—mainly slender-billed Pachyptila belcheri—and Salvin’s albatross Thalassarche [cauta]salvini. The eight more abundant species represented 2650 birds, i.e. more than 80% of the total. A random forest clustering method identified four groups of seabird species occupying similar oceanographic niches.

关键词： seabird at-sea distribution transect from New Zealand to Antarctica hydrographic features

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

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Advances in Polar Science 2015年第4期26卷 265-273页

作者： claude r.joiris Grant r.W.Humphries Alain De Broyer Laboratory for Polar Ecology (PolE) Conservation Biology Unit Royal Belgian Institute for Natural Sciences (RBINS) Department of Ecology and Evolution Stony Brook University

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.

关键词： marine mammals at-sea distribution Antarctica

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

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Advances in Polar Science 2015年第4期26卷 282-291页

作者： claude r.joiris Grant r.W.Humphries Diederik D'Hert rené-Marie Lafontaine Henri robert roseline C.Beudels-Jamar Laboratory for Polar Ecology (PolE) Conservation Biology Unit Royal Belgian Institute for Natural Sciences Department of Ecology and Evolution. Stony Brook University

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.

关键词： Scotia Sea Scotia ridge Scotia Trench seabirds & marine mammals southern right whale Antarcticfur seal Antarctic prion