Morphological dietary composition of Antarctic toothfish (Dissostichus mawsoni) along the East Antarctic continental slope

Abstract To predict how the fishing of Antarctic toothfish, Dissostichus mawsoni , would affect the ecosystem, it is necessary to understand the species’ ecological niche. Morphological analysis of the stomach contents of 960 D . mawsoni specimens collected at depths of 946–1,600 m along the East Antarctic continental slope from December 2016 to March 2017 was used to assess dietary composition according to depth, sex, site, and size. Fishes were the most common prey item for D . mawsoni , comprising 97.8% based on the index of relative importance. Among the nine fish families consumed by D . mawsoni , Macrouridae was the dominant taxon. The size of D . mawsoni increased with depth. The dietary composition of D . mawsoni did not show significant differences by depth or sex, but did differ with site and size. D . mawsoni was the top predator in the ecosystem along the East Antarctic continental slope and can be considered an opportunistic feeder, feeding on abundant food in the environment. Therefore, additional studies of the diet of Antarctic toothfish are necessary to maintain the ecosystem structure and function in a changing environment, and the results of this study can be used as a monitoring baseline.

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Morphological dietary composition of Antarctic toothfish (Dissostichus mawsoni) along the East Antarctic continental slope

Polar Biology ◽

10.1007/s00300-021-02820-9 ◽

2021 ◽

Author(s):

Gi Chang Seong ◽

Seok-Gwan Choi ◽

Sangdeok Chung ◽

Doo Hae An ◽

Hyun-Woo Kim ◽

...

Keyword(s):

Continental Slope ◽

Dietary Composition ◽

Antarctic Toothfish ◽

Dissostichus Mawsoni

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The effects of modern war and military activities on biodiversity and the environment

Environmental Reviews ◽

10.1139/er-2015-0039 ◽

2015 ◽

Vol 23 (4) ◽

pp. 443-460 ◽

Cited By ~ 46

Author(s):

Michael J. Lawrence ◽

Holly L.J. Stemberger ◽

Aaron J. Zolderdo ◽

Daniel P. Struthers ◽

Steven J. Cooke

Keyword(s):

Military Training ◽

Structure And Function ◽

Aquatic Systems ◽

Ecosystem Structure ◽

Population Declines ◽

Exclusion Zone ◽

Negative Effects ◽

And Function ◽

Ecosystem Structure And Function ◽

Modern War

War is an ever-present force that has the potential to alter the biosphere. Here we review the potential consequences of modern war and military activities on ecosystem structure and function. We focus on the effects of direct conflict, nuclear weapons, military training, and military produced contaminants. Overall, the aforementioned activities were found to have overwhelmingly negative effects on ecosystem structure and function. Dramatic habitat alteration, environmental pollution, and disturbance contributed to population declines and biodiversity losses arising from both acute and chronic effects in both terrestrial and aquatic systems. In some instances, even in the face of massive alterations to ecosystem structure, recovery was possible. Interestingly, military activity was beneficial under specific conditions, such as when an exclusion zone was generated that generally resulted in population increases and (or) population recovery; an observation noted in both terrestrial and aquatic systems. Additionally, military technological advances (e.g., GPS technology, drone technology, biotelemetry) have provided conservation scientists with novel tools for research. Because of the challenges associated with conducting research in areas with military activities (e.g., restricted access, hazardous conditions), information pertaining to military impacts on the environment are relatively scarce and are often studied years after military activities have ceased and with no knowledge of baseline conditions. Additional research would help to elucidate the environmental consequences (positive and negative) and thus reveal opportunities for mitigating negative effects while informing the development of optimal strategies for rehabilitation and recovery.

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Environmental ecology: The impacts of pollution and other stresses on ecosystem structure and function

Ecological Economics ◽

10.1016/0921-8009(91)90028-d ◽

1991 ◽

Vol 4 (2) ◽

pp. 168-169

Author(s):

Nils Kautsky

Keyword(s):

Structure And Function ◽

Ecosystem Structure ◽

And Function ◽

Ecosystem Structure And Function

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Experimental warming differentially affects vegetative and reproductive phenology of tundra plants

Nature Communications ◽

10.1038/s41467-021-23841-2 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Courtney G. Collins ◽

Sarah C. Elmendorf ◽

Robert D. Hollister ◽

Greg H. R. Henry ◽

Karin Clark ◽

...

Keyword(s):

Growing Season ◽

Plant Phenology ◽

Reproductive Phenology ◽

Ecosystem Structure ◽

Experimental Warming ◽

Growing Seasons ◽

Tundra Ecosystem ◽

Phenological Shifts ◽

And Function ◽

Ecosystem Structure And Function

AbstractRapid climate warming is altering Arctic and alpine tundra ecosystem structure and function, including shifts in plant phenology. While the advancement of green up and flowering are well-documented, it remains unclear whether all phenophases, particularly those later in the season, will shift in unison or respond divergently to warming. Here, we present the largest synthesis to our knowledge of experimental warming effects on tundra plant phenology from the International Tundra Experiment. We examine the effect of warming on a suite of season-wide plant phenophases. Results challenge the expectation that all phenophases will advance in unison to warming. Instead, we find that experimental warming caused: (1) larger phenological shifts in reproductive versus vegetative phenophases and (2) advanced reproductive phenophases and green up but delayed leaf senescence which translated to a lengthening of the growing season by approximately 3%. Patterns were consistent across sites, plant species and over time. The advancement of reproductive seasons and lengthening of growing seasons may have significant consequences for trophic interactions and ecosystem function across the tundra.

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