Moseley's Rockhopper Penguin (Eudyptes moseleyi)

2020 ◽  
Author(s):  
Josep del Hoyo ◽  
Nigel Collar ◽  
Ernest Garcia
Keyword(s):  

2015 ◽  
Vol 93 (2) ◽  
pp. 123-131 ◽  
Author(s):  
Brian G. Walker ◽  
P. Dee Boersma ◽  
John C. Wingfield

Comparing baseline and stress-induced glucocorticoid hormone levels in animals is a popular tool to assess differences in stress experienced among groups. We compare corticosterone levels in Magellanic Penguins (Spheniscus magellanicus (J.R. Forster, 1781)) in situations where we hypothesize differences in stress patterns may exist. We compared penguins both within and between breeding seasons, birds breeding at two different locations, penguins at three different ages, penguins that had shown evidence of recent fighting, and, finally, how stress patterns differed for four different penguin species. Throughout a breeding season (settlement, incubation, and chick-rearing), we found no differences in either baseline or stress-induced hormone concentrations. Chick, juvenile, and adult penguins did not differ in baseline corticosterone levels, but juveniles had a reduced stress response. Penguins in one season showed a stress response to capture, likely due to a recent severe weather event. We found no differences in baseline or stress-induced hormone titers for birds from two different breeding locations. Evidence of recent fighting also did not alter baseline corticosterone levels. Finally, among four species of penguins measured (Magellanic, Humboldt (Spheniscus humboldti Meyen, 1834), Galápagos (Spheniscus mendiculus Sundevall, 1871), and Rockhopper (Eudyptes chrysocome (J.R. Forster, 1781)), baseline levels were always consistent, while stress-induced levels were significantly higher in the Rockhopper Penguin only.



Polar Biology ◽  
2016 ◽  
Vol 40 (4) ◽  
pp. 735-751 ◽  
Author(s):  
Kyle W. Morrison ◽  
Doug P. Armstrong ◽  
Phil F. Battley ◽  
Sarah E. Jamieson ◽  
David R. Thompson


2019 ◽  
Author(s):  
Kerry-Jayne Wilson ◽  
Thomas Mattern
Keyword(s):  


1986 ◽  
Vol 64 (4) ◽  
pp. 963-972 ◽  
Author(s):  
Jacob G. Sivak ◽  
Rebecca F. Glover

The anatomy of the membrana nictitans was examined in the rockhopper penguin (Eudyptes crestatus) and in two ducks, a diver (Mergus cucullatus, hooded merganser) and a nondiver (Anas platyrhynchos, common mallard), by light and transmission electron microscopy. In general, the nictitans is organized in a manner reminiscent of the cornea; i.e., an external epithelium, an internal endothelium, and a fibrous stromal layer in between. However, it is thinner than the cornea, a fact reflected by the relatively thin stroma. Nictitans organization varies between species and in different regions of the same membrane. The cellular and acellular components are less organized and not as tighltly packed in the nondiver than in the two other species. In addition, portions of the nictitans that would be coincident with the cornea when it is in place in front of the eye are more highly organized in both divers. The anatomy of the leading edge of the nictitans, including the marginal plait, which may help lock the membrane in position, is described.





PLoS ONE ◽  
2013 ◽  
Vol 8 (11) ◽  
pp. e79487 ◽  
Author(s):  
Nina Dehnhard ◽  
Katrin Ludynia ◽  
Maud Poisbleau ◽  
Laurent Demongin ◽  
Petra Quillfeldt




Polar Biology ◽  
2008 ◽  
Vol 31 (8) ◽  
pp. 925-932 ◽  
Author(s):  
Maud Poisbleau ◽  
Laurent Demongin ◽  
Ian J. Strange ◽  
Helen Otley ◽  
Petra Quillfeldt


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