Stable carbon and nitrogen isotope trophic enrichment factors for Steller sea lion vibrissae relative to milk and fish/invertebrate diets

2015 ◽  
Vol 523 ◽  
pp. 255-266 ◽  
Author(s):  
CA Stricker ◽  
AM Christ ◽  
MB Wunder ◽  
AC Doll ◽  
SD Farley ◽  
...  
Keyword(s):  
Nitrogen Isotope ◽  
Enrichment Factors ◽  
Steller Sea Lion ◽  
Stable Carbon ◽  
Sea Lion ◽  
Carbon And Nitrogen ◽  
Trophic Enrichment

Stable-isotope and electron-microscopic evidence that cyamids (Crustacea: Amphipoda) feed on whale skin

2000 ◽  
Vol 78 (5) ◽  
pp. 721-727 ◽  
Author(s):  
Donald M Schell ◽  
Victoria J Rowntree ◽  
Carl J Pfeiffer
Keyword(s):  
Stable Isotope ◽  
Food Source ◽  
Nitrogen Isotope ◽  
Isotope Ratios ◽  
Observational Evidence ◽  
Food Sources ◽  
Stable Carbon ◽  
Electron Microscopic ◽  
Carbon And Nitrogen ◽  
Trophic Enrichment

Cyamids (Crustacea: Amphipoda) are found only on whales. Observational evidence and the morphology of the mouthparts have indicated that whale skin is the primary food for these organisms. It has also been suggested, however, that the cyamids may be feeding on epidermal diatoms and meiofauna associated with the skin or using the whales as transport to regions of high zooplankton densities, where small pelagic organisms are captured while the whales feed. Here we report electron-microscopic and isotopic evidence that whale skin was ingested and assimilated by cyamids. Stable carbon and nitrogen isotope ratios of cyamids and whale skin from six species of whales were compared with those of zooplankton from the regions through which the whales migrate, to infer the most likely food sources. In all cases, cyamid isotope ratios closely matched those of the whale skin and not those of the zooplankton, again indicating that whale skin was the predominant food source. Unlike most other carnivorous organisms, cyamids do not show a trophic enrichment of δ15N, a trait also found in other species of Amphipoda.

scholarly journals Spatial and Seasonal Variations of Sedimentary Organic Matter in a Subtropical Bay: Implication for Human Interventions

2020 ◽  
Vol 17 (4) ◽  
pp. 1362 ◽  
Author(s):  
Xuan Lu ◽  
Fengxia Zhou ◽  
Fajin Chen ◽  
Qibin Lao ◽  
Qingmei Zhu ◽  
...  
Keyword(s):  
Organic Matter ◽  
Surface Sediment ◽  
Seasonal Variations ◽  
Seasonal Changes ◽  
Nitrogen Isotope ◽  
Anthropogenic Influences ◽  
Stable Carbon ◽  
Δ13c And Δ15n ◽  
Carbon And Nitrogen ◽  
Induced Changes

Elemental (total organic carbon (TOC) and total nitrogen (TN)) and stable carbon and nitrogen isotope compositions (δ13C and δ15N, respectively) in the surface sediment of Zhanjiang Bay (ZJB) in spring and summer were measured to study the spatial and seasonal changes of organic matter (OM) and assess the human-induced and environment-induced changes in the area. The OM in the surface sediment of ZJB was a mixture of terrestrial and marine sources, and was dominated by marine OM (54.9% ± 15.2%). Compared to the central ZJB, the channel and coastal ZJB areas had higher δ13C and δ15N values, higher TOC and TN concentrations, and lower TOC/TN ratios, indicating higher primary productivity and higher percentages of marine OM in the latter two subregions. Mariculture activities, sewage inputs, and dredging were responsible for these phenomena. Clear seasonal variations in OM were observed in ZJB. The average proportions of terrestrial OM in summer increased by 10.2% in the ZJB channel and 26.0% in the coastal ZJB area compared with those in spring. Heavy rainfall brought a large amount of terrestrial OM into the channel and coastal ZJB areas, leading to the increase of the terrestrial OM fraction in these two subregions in summer. In summary, anthropogenic influences had a significant influence on the spatial and seasonal variations of sedimentary OM in ZJB.

scholarly journals Hair cortisol and stable carbon and nitrogen isotope ratios in barbary macaques ( Macaca sylvanus ) from Gibraltar

2019 ◽  
Vol 33 (9) ◽  
pp. 831-838 ◽  
Author(s):  
Michael A. Schillaci ◽  
Jessica Lintlop ◽  
Monika Sumra ◽  
Mark Pizarro ◽  
Lisa Jones‐Engel
Keyword(s):  
Nitrogen Isotope ◽  
Isotope Ratios ◽  
Hair Cortisol ◽  
Stable Carbon ◽  
Macaca Sylvanus ◽  
Barbary Macaques ◽  
Carbon And Nitrogen

scholarly journals Diet and disease in Tomar, Portugal: Comparing stable carbon and nitrogen isotope ratios between skeletons with and without signs of infectious disease

2019 ◽  
Vol 105 ◽  
pp. 59-69 ◽  
Author(s):  
Ana Curto ◽  
Patrick Mahoney ◽  
Anne-France Maurer ◽  
Cristina Barrocas-Dias ◽  
Teresa Fernandes ◽  
...  
Keyword(s):  
Infectious Disease ◽  
Nitrogen Isotope ◽  
Isotope Ratios ◽  
Stable Carbon ◽  
Carbon And Nitrogen
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