Observations of a newborn Ross seal pup (Ommatophoca rossi) near the Antarctic Peninsula

1980 ◽  
Vol 58 (11) ◽  
pp. 2156-2158 ◽  
Author(s):  
J. Thomas ◽  
D. DeMaster ◽  
S. Stone ◽  
D. Andriashek

A Ross seal mother and male pup (Ommatophoca rossi) were sighted on 14 November 1978 in Dallmann Bay near the Antarctic Peninsula. This is believed to be the first documented observation of a newborn Ross seal. Behavioral observations and standard measurements taken from this pup enhance the small amount of information known about the early life of the species.

2010 ◽  
Vol 67 (8) ◽  
pp. 1303-1315 ◽  
Author(s):  
Julian Ashford ◽  
Mario La Mesa ◽  
Bettina A. Fach ◽  
Christopher Jones ◽  
Inigo Everson

We measured the otolith chemistry of adult Scotia Sea icefish ( Chaenocephalus aceratus ), a species with a long pelagic larval phase, along the Antarctic Circumpolar Current (ACC) and compared the chemistry with simulated particle transport using a circulation model. Material laid down in otolith nuclei during early life showed (i) strong heterogeneity between the Antarctic Peninsula and South Georgia consistent with a population boundary, (ii) evidence of finer-scale heterogeneity between sampling areas on the Antarctic Peninsula, and (iii) similarity between the eastern and northern shelves of South Georgia, indicating a single, self-recruiting population there. Consistent with the otolith chemistry, simulations of the large-scale circulation predicted that particles released at depths of 100–300 m on the Antarctic Peninsula shelf during spring, corresponding to hatching of icefish larvae from benthic nests, are transported in the southern ACC, missing South Georgia but following trajectories along the southern Scotia Ridge instead. These results suggest that the timing of release and position of early life stages in the water column substantially influence the direction and extent of connectivity. Used in complement, the two techniques promise an innovative approach for generating and testing predictions to resolve early dispersal and connectivity of populations related to the physical circulation of oceanic systems.


2015 ◽  
Vol 24 (2) ◽  
pp. 150-161 ◽  
Author(s):  
Mario La Mesa ◽  
Andrea Piñones ◽  
Barbara Catalano ◽  
Julian Ashford

2021 ◽  
Author(s):  
James Brean ◽  
Manuel Dall’Osto ◽  
Rafel Simó ◽  
Zongbo Shi ◽  
David C. S. Beddows ◽  
...  

2021 ◽  
pp. 1-27
Author(s):  
H. Jay Zwally ◽  
John W. Robbins ◽  
Scott B. Luthcke ◽  
Bryant D. Loomis ◽  
Frédérique Rémy

Abstract GRACE and ICESat Antarctic mass-balance differences are resolved utilizing their dependencies on corrections for changes in mass and volume of the same underlying mantle material forced by ice-loading changes. Modeled gravimetry corrections are 5.22 times altimetry corrections over East Antarctica (EA) and 4.51 times over West Antarctica (WA), with inferred mantle densities 4.75 and 4.11 g cm−3. Derived sensitivities (Sg, Sa) to bedrock motion enable calculation of motion (δB0) needed to equalize GRACE and ICESat mass changes during 2003–08. For EA, δB0 is −2.2 mm a−1 subsidence with mass matching at 150 Gt a−1, inland WA is −3.5 mm a−1 at 66 Gt a−1, and coastal WA is only −0.35 mm a−1 at −95 Gt a−1. WA subsidence is attributed to low mantle viscosity with faster responses to post-LGM deglaciation and to ice growth during Holocene grounding-line readvance. EA subsidence is attributed to Holocene dynamic thickening. With Antarctic Peninsula loss of −26 Gt a−1, the Antarctic total gain is 95 ± 25 Gt a−1 during 2003–08, compared to 144 ± 61 Gt a−1 from ERS1/2 during 1992–2001. Beginning in 2009, large increases in coastal WA dynamic losses overcame long-term EA and inland WA gains bringing Antarctica close to balance at −12 ± 64 Gt a−1 by 2012–16.


Sign in / Sign up

Export Citation Format

Share Document