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1

Cestodes from penguins on King George Island [South Shetlands, Antarctic]

100%
Cielecka D., Wojciechowska A., Zdzitowiecki K.
Acta Parasitologica
|
1992
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tom 37
|
nr 2
The paper contains descriptions of three species of cestodes from three species of penguins on King George Island: Parorchites zederi (Baird, 1853) in Pygoscelis papua, P. antarctica and P. adeliae, Tetrabothrius pauliani Joyeux et Baer, 1954 in P. antarctica and P. adeliae and T. joubini Railliet et Henry, 1912 in P. antarctica. Tetrabothrius pauliani is recorded for the first time in the South Shetlands, and P. adeliae is a new host record of this parasite. A description is given of P. zederi cercoids found in seal intestine. The question of the geographical distribution of the species under study is discussed, as well as the problem of the life cycle of P. zederi.
2
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Change in N and P concentrations in Antarctic streams as a response to change in penguin populations

63%
Nedzarek A.
Papers on Global Change
|
2010
|
nr 17
This study presents changes in the concentrations of nitrogen and phosphorus in two streams in Western Antarctica (Admiralty Bay, King George Island, South Shetlands) that differ in trophic status. The results suggest a decline in concentrations of the determined forms of N and P between 2001 and 2005. The decrease ranged from 9.3% for reactive phosphorus to 73.2% for ammonium-nitrogen. Such inferred declines in N and P concentrations are considered to reflect reduced deposition on land of organic matter brought in from the seas by the penguins nesting in the area. The ultimate cause of this is in turn the steady decline in abundance that is being noted for these penguins.
3

Taxonomic revision of Eocene Antarctic penguins based on tarsometatarsal morphology

63%
Myrcha A., Jadwiszczak P., Tambussi C. P., Noriega J. I., Gazdzicki A., Tatur A., Del Valle R. A.
Polish Polar Research
|
2002
|
tom 23
|
nr 1
5-46
4

Is cleaning penguins worth the effort? Results from flipper banding

63%
Whittington P.
The Ring
|
1997
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tom 19
|
nr 1-2
5
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The oldest fossil record of the extant penguin genus Spheniscus - a new species from the Miocene of Peru

63%
Gohlich U. B.
Acta Palaeontologica Polonica
|
2007
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tom 52
|
nr 2
Described here is a partial postcranial skeleton and additional disarticulated but associated bones of the new fossil penguin Spheniscus muizonisp. nov. from the latest middle/earliest late Miocene (11–13 Ma) locality of Cerro la Bruja in the Pisco Formation, Peru. This fossil species can be attributed to the extant genus Spheniscus by postcranial morphology and is the oldest known record of this genus. Spheniscus muizonisp. nov. is about the size of the extant Jackass and Magellanic penguins (Spheniscus demersus and Spheniscus magellanicus). Beside Spheniscus urbinai and Spheniscus megaramphus it is the third species of Spheniscus represented in the Pisco Formation. This study contains morphological comparisons with Tertiary penguins of South America and with most of the extant penguin species.
6
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A new Miocene penguin from Patagonia and its phylogenetic relationships

63%
Acosta H. C., Tambussi C., Donato M., Cozzuol M.
Acta Palaeontologica Polonica
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2007
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tom 52
|
nr 2
We describe a new medium−sized penguin, Madrynornis mirandus gen. et sp. nov., from the early late Miocene Puerto Madryn Formation, Chubut Province, Argentina. Although it is evident that extant and fossil penguins form a remarkably homogeneous family of birds, Spheniscidae, their within−group phylogenetic relationships are less obvious. In order to identify the phylogenetic position of the new taxon, we conducted a phylogenetic analysis using 44 osteological characters sampled from 14 representative species of all living genera and five fossil species of Spheniscidae. The family is clearly monophyletic and Madrynornis mirandus is closely related to living taxa. Our phylogenetic interpretation is congruent with biostratigraphic data, with Paraptenodytes from the early Miocene (about 20 Ma) located at the base of the Spheniscidae. Classically, two basic tarsometatarsal types were recognized (one for pre−Miocene and the other for the post−Miocene penguins) based on the pattern of the proximal foramina and the hypotarsus. Madrynornis mirandus exhibits an arrangement of the proximal foramina and a degree of metatarsals fusion similar to that in the living forms, although its elongation index (total length/proximal width) is reminiscent of the extinct Paraptenodytes(a penguin historically recognized as a pre−Miocene form, coming from the early Miocene of Argentina). Madrynornis reveals that the two basic tarsometatarsal types co−existed among Miocene penguins.
7

Nutrients and cations content in soil solutions from the present and abandoned penguin rookeries [Antarctica, King George Island]

63%
Juchnowicz-Bierbasz M., Rakusa-Suszczewski S.
Polish Journal of Ecology
|
2002
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tom 50
|
nr 1
Penguin rookeries are one of the main sources of nutrients for the poor ecosystems of Antarctica. At the current penguin rookeries, and in their vicinity, nitrogen rich ornithogenic soils are formed. Relict ornithogenic soils created at the abandoned rookeries hundreds or even thousands years ago are rich in phosphates. In the region of maritime Antarctica, water plays an important role in distribution and redistribution of nutrients (surface flows and percolation). Soil decomposition processes result in cations and nutrient release. In nutrients originating from relict ornithogenic soils of the Antarctic tundra, phosphates are the dominating elements; while in nutrients originating from contemporary ornithogenic soils nitrogen (mainly ammonia) is the main ingredient. Mineral soils free of penguin influence contain minute amounts of nutrients. Low pH of soil solutions (<4) causes increase of dissolving of phosphate complexes. Near penguin rookery, pH was lowest (2.73-3.33) and intermediate (2.92-3.77) in relict soils. The values of pH were the highest in soil solutions from mineral soil (5.43-7.33). High concentration of cations (mainly K) in soil solutions from the ornithogenic soils and relict ornithogenic soils, suggest their organic (animal) origin.
8

Eocene penguins of Seymour Island, Antarctica: The earliest record, taxonomic problems and some evolutionary considerations

51%
Jadwiszczak P.
Polish Polar Research
|
2006
|
tom 27
|
nr 4
287-302
Penguin bones from the La Meseta Formation (Seymour Island, Antarctic Peninsula) are the only record of Eocene Antarctic Sphenisciformes. Being an abundant component of the youngest unit of the formation (Telm7), they are not so common in earlier strata. Here, I present the oldest penguin remains from the La Meseta Formation (Telm1-Telm2), often bearing close resemblance to their counterparts from younger units. Addressing the recent findings in fossil penguin systematics, I suggest there is too weak a basis for erecting new Eocene Antarctic taxa based on non-tarsometatarsal elements of penguin skeletons, and considering Oligocene species part of the studied assemblage. Finally, I conclude if the common ancestor of extant Sphenisciformes lived in the Eocene Antarctic (as suggested recently), penguins referred to Delphinornis seem to be prime candidates to that position.
9

Additions to the lichen flora of Victoria Land, Antarctica

51%
Smykla J., Krzewicka B., Wilk K., Emslie S. D., Sliwa L.
Polish Polar Research
|
2011
|
tom 32
|
nr 2
10

Persistent organic pollutants (POPs) in the marine food web: herrings from the Southern Baltic Sea (Clupea harengus) - penguins from the zoo (Spheniscus demersus)

51%
Reindl A. R., Bolalek J., Falkowska L.
Oceanological and Hydrobiological Studies
|
2013
|
tom 42
|
nr 1
11

Eocene penguins of Seymour Island, Antarctica: Taxonomy

51%
Jadwiszczak P.
Polish Polar Research
|
2006
|
tom 27
|
nr 1
3-62
Skeletal remains of penguins from the Eocene La Meseta Formation (Seymour Island, Antarctica) constitute the only extensive fossil record of Antarctic Sphenisciformes. No articulated skeletons are known, and almost all fossils occur as single isolated elements. Most of the named species are based on tarsometatarsi (for which the taxonomy was revised in 2002). Here, 694 bones (from the Polish collection) other than tarsometatarsi are reviewed, and allocated to species. They confirm previous conclusions and suggest that ten species grouped in six genera are a minimal reliable estimate of the Eocene Antarctic penguin diversity. The species are: Anthropornis grandis, A. nordenskjoeldi, Archaeospheniscus wimani, Delphinornis arctowskii, D. gracilis, D. larseni, Marambiornis exilis, Mesetaornis polaris, Palaeeudyptes gunnari and P. klekowskii. Moreover, diagnoses of four genera (Anthropornis, Archaeospheniscus, Delphinornis and Palaeeudyptes) and two species (P. gunnari and P. klekowskii) are supplemented with additional, non-tarsometatarsal features. Four species of the smallest penguins from the La Meseta Formation (D. arctowskii, D. gracilis, M. exilis and M. polaris) seem to be the youngest taxa within the studied assemblage - their remains come exclusively from the uppermost unit of the formation. All ten recognized species may have co-existed in the Antarctic Peninsula region during the Late Eocene epoch.
12
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Aspects of diversity in early Antarctic penguins

51%
Jadwiszczak P., Mors T.
Acta Palaeontologica Polonica
|
2011
|
tom 56
|
nr 2
Penguin bones from the Eocene La Meseta Formation (Seymour Island, Antarctic Peninsula) constitute the only extensive fossil record of Antarctic Sphenisciformes. Here, we synonymize some of the recognized genera (Anthropornis with Orthopteryx, Delphinornis with Ichtyopteryx) and species (Anthropornis nordenskjoeldi with Orthopteryx gigas, Delphinornis gracilis with Ichtyopteryx gracilis). Moreover, we suggest that Antarctic species of Anthropornis and Palaeeudyptes, so−called giant penguins, may in fact comprise only one species each instead of two, based on evidence of well−marked sexual dimorphism. We also present new estimates of body mass based on femora testifying to the impressive scope of interspecific body−size variation in Eocene Antarctic penguins.
13

Enigmatic morphological disparity in tarsometatarsi of giant penguins from the Eocene of Antarctica

51%
Acosta Hospitaleche C., Jadwiszczak P.
Polish Polar Research
|
2011
|
tom 32
|
nr 2
14
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Climate change influences on Antarctic bird populations

45%
Korczak-Abshire M.
Papers on Global Change
|
2010
|
nr 17
Rapid changes in the major environmental variables like: temperature, wind and precipitation have occurred in the Antarctic region during the last 50 years. In this very sensitive region, even small changes can potentially lead to major environmental perturbations. Then the climate change poses a new challenge to the survival of Antarctic wildlife. As important bioindicators of changes in the ecosystem seabirds and their response to the climate perturbations have been recorded. Atmospheric warming and consequent changes in sea ice conditions have been hypothesized to differentially affect predator populations due to different predator life-history strategies and substantially altered krill recruitment dynamics.
15

Coccidian parasites (Apicomplexa) of penguins (Pygoscelis ssp.) from Livingston Island and King George Island, the Antarctic

45%
Golemansky V.
Polish Polar Research
|
2011
|
tom 32
|
nr 3
16

Diet of the Adelie penguin during three consecutive chick rearing periods at Laurie Island

45%
Libertelli M. M., Coria N., Marateo G.
Polish Polar Research
|
2003
|
tom 24
|
nr 2
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