Predicting early life connectivity of Antarctic silverfish, an important forage species along the Antarctic Peninsula

2015 ◽  
Vol 24 (2) ◽  
pp. 150-161 ◽  
Author(s):  
Mario La Mesa ◽  
Andrea Piñones ◽  
Barbara Catalano ◽  
Julian Ashford
Keyword(s):  
Antarctic Peninsula ◽  
Early Life ◽  
Forage Species ◽  
Antarctic Silverfish ◽  
The Antarctic

Influence of environmental conditions on spatial distribution and abundance of early life stages of Antarctic silverfish,Pleuragramma antarcticum(Nototheniidae), in the Ross Sea

2010 ◽  
Vol 22 (3) ◽  
pp. 243-254 ◽  
Author(s):  
Mario La Mesa ◽  
Barbara Catalano ◽  
Aniello Russo ◽  
Silvio Greco ◽  
Marino Vacchi ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Early Life ◽  
General Circulation ◽  
Ross Sea ◽  
Life Stages ◽  
Early Life Stages ◽  
Pleuragramma Antarcticum ◽  
Antarctic Silverfish ◽  
The Antarctic ◽  
Western Ross Sea

AbstractThe Antarctic silverfishPleuragramma antarcticumBoulenger is the dominant fish species in the high Antarctic zone, playing a key role in the Ross Sea midwater shelf ecosystem. Unlike other notothenioids, it is holoplanktonic species, spending its entire life cycle in the water column. Early life stages ofP. antarcticumare generally found in the upper 200 m and their spatial distribution is largely affected by water masses and general circulation. To understand better the mechanisms involved in the geographical distribution of the Antarctic silverfish within the western Ross Sea, an analysis of abundance and distribution was carried out in relation to oceanographic conditions. Samples were collected in summer during the 1998, 2000 and 2004 Italian cruises, covering the majority of the western sector of the Ross Sea. Overall 127 stations were sampled using standard plankton nets for biological samples and CTD and XBT to record abiotic parameters. Although all surveys were in December–January, the yearly results differed in terms of relative abundance of larval developmental stages and of oceanographic characteristics. The 1997–98 samples were characterized by very low abundance overall and by the virtual absence of early larvae. In summers 1999–2000 and 2003–04 the abundance ofP. antarcticumwas one order of magnitude higher than in the earlier season. In 1999–2000 catches were mainly composed of pre-flexion larvae and late postlarvae, while in 2003–04 catches were made up of pre-flexion larvae and juveniles. In January 2000 the Ross Sea summer polynya was fully open as the pack ice was almost completely melted, whereas in January 1998 and 2004 the opening of the polynya was considerably delayed. As a consequence, a delay in phytoplankton blooms and a decrease in primary production were observed in the summer seasons 1998 and 2004 with respect to 2000. The spatial distribution of early life stages, that were confined to the continental shelf and shelf break of the Ross Sea, generally appeared to be positively influenced by transition zones (oceanographic fronts). In addition, most of catches were recorded on or in close proximity to the banks (Pennell, Mawson, Ross and Crary) that characterize the continental shelf of the Ross Sea. On the basis of present findings and literature data, a link between the general circulation in the western Ross Sea and the distribution pattern of the early life stages ofP. antarcticumhas been developed.

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
Keyword(s):  
Antarctic Peninsula ◽  
Early Life ◽  
Amount Of Information ◽  
Behavioral Observations ◽  
The Antarctic

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.

Testing early life connectivity using otolith chemistry and particle-tracking simulations

2010 ◽  
Vol 67 (8) ◽  
pp. 1303-1315 ◽  
Author(s):  
Julian Ashford ◽  
Mario La Mesa ◽  
Bettina A. Fach ◽  
Christopher Jones ◽  
Inigo Everson
Keyword(s):  
Antarctic Peninsula ◽  
Early Life ◽  
Large Scale ◽  
Circulation Model ◽  
Model Material ◽  
Otolith Chemistry ◽  
Larval Phase ◽  
Scotia Sea ◽  
South Georgia ◽  
The Antarctic

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.

scholarly journals Open ocean and coastal new particle formation from sulfuric acid and amines around the Antarctic Peninsula

2021 ◽  
Author(s):  
James Brean ◽  
Manuel Dall’Osto ◽  
Rafel Simó ◽  
Zongbo Shi ◽  
David C. S. Beddows ◽  
...  
Keyword(s):  
Sulfuric Acid ◽  
Antarctic Peninsula ◽  
Particle Formation ◽  
Open Ocean ◽  
New Particle Formation ◽  
The Antarctic
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