Spatial and Temporal Patterns of Arctic Nearshore Fish Community and Food Web Structures

Authors

Mark B. Barton, Florida International UniversityFollow

Document Type

Dissertation

Degree

Doctor of Philosophy (PhD)

Major/Program

Biology

First Advisor's Name

Kevin Boswell

First Advisor's Committee Title

Committee chair

Second Advisor's Name

Joel Trexler

Second Advisor's Committee Title

Committee member

Third Advisor's Name

Alastair Harborne

Third Advisor's Committee Title

Committee member

Fourth Advisor's Name

William Anderson

Fourth Advisor's Committee Title

Committee member

Fifth Advisor's Name

Alexei Pinchuk

Fifth Advisor's Committee Title

Committee member

Keywords

arctic, fish, food web, nearshore, community, structure, composition, stable isotopes, point barrow

Date of Defense

6-29-2018

Abstract

Climate change and increasing anthropogenic activities are causing rapid changes to environmental and ecological processes in the Arctic Ocean. To better understand these changes, scientists have increased research efforts in these regions, but to date the number of studies on Arctic nearshore habitats are lacking. My dissertation responds to the paucity of information and investigates patterns in Arctic nearshore fish communities and food webs to gain insight to how these ecosystems may shift as these changes continue. I used multivariate statistical analysis to examine patterns in community structure and composition to determine that Arctic nearshore fish communities are largely driven by prey availability, salinity and temperature; and that species that are more abundant in warmer conditions are likely to increase in abundance as climatic conditions in the Arctic continue to warm. I improved the ability to apply stable isotope methods to Arctic food web studies by determining more appropriate model parameters using a laboratory-based isotope study on a common Arctic nearshore fish, and discuss its potential as a biological monitor species. These new parameters are used to confirm that a shift in prey resource dependence occurs across the seasonal shift from ice-covered winter to open-water summer conditions. Changes in basal resource dependence also occur later in the season across a latitudinal gradient where a shift to dependence on allochtonous inputs from nearby rivers increased trophic diversity. Using isotopic niche space theory, it was determined that the Arctic nearshore has a diverse prey base but that niche spaces of Arctic warm-water and cold-water species do overlap, and if numbers of warm-water fish continue to increase it will likely increase competition for resources for potentially less-adaptable, well-established, cold-water forage fish. On the other hand, if pelagic productivity is expected to increase and support larger fish biomasses, then there will be more than enough resources for warm-water and cold-water species to coexist, thus creating a more diverse prey base for piscivores in the Arctic.

Identifier

FIDC006901

Recommended Citation

Barton, Mark B., "Spatial and Temporal Patterns of Arctic Nearshore Fish Community and Food Web Structures" (2018). FIU Electronic Theses and Dissertations. 3735.
https://digitalcommons.fiu.edu/etd/3735