Feeding ecology of benthic mobile predators: experimental analyses of their influence in rocky subtidal communities of the Gulf of Maine

In the early 1980s, the National Oceanic and Atmospheric Administration (NOAA) initiated an ecosystem analysis of Gouldsboro Bay in eastern Maine as part of a planned marine sanctuary. The original report to NOAA by Walter H. Adey was not published after the sanctuary concept for Maine was abandoned. Because significant human-related climatic and ecosystem changes are underway in the Gulf of Maine, that report provides valuable baseline data and is included as the Appendix to this volume. After qualitatively describing the geological, physical, chemical, and biogeographical features of Gouldsboro Bay and adjacent Dyer Bay, we quantitatively describe the principal bay ecological communities with data collected during the 1981–1983 ecosystem assessment as well as additional measurements taken within the past decade. We then undertake a comparison of the primary productivity of these bays with the Google Earth Pro polygon tool to determine component areas. Benthic taxa are the dominant primary producers in both bays: rockweeds (primarily Ascophyllum nodosum, with Fucus vesiculosus secondary) in the intertidal; Irish moss (Chondrus crispus, with Fucus distichus secondary) as a near monoculture in the lowest intertidal (infralittoral); kelps (primarily Saccharina latissima, Laminaria digitata, and Agarum clathratum) in the rocky subtidal; and the angiosperm Zostera marina (seagrass) in soft bottom substrate. The rocky intertidal, dominated by Ascophyllum with a specific productivity of 10.6 kg/m2/year, provides nearly one-third of all bay productivity. Because of the proportionally greater shore length relative to area of Dyer Bay, it has 45% greater productivity for its surface area than Gouldsboro Bay. Kelp has a specific productivity value of 7.2 kg/m2/year, and Zostera of 1.2 kg/m2/year. The kelps provide approximately 20% of Gouldsboro Bay’s primary productivity and 35% of that of Dyer Bay. Zostera provides roughly 20% of total primary productivity in Gouldsboro Bay and 12% in Dyer Bay. With a primary productivity of 1.73 kg/m2/year, salt marshes provide only 3.7% (Gouldsboro) and 2.6% (Dyer) of total primary productivity. With a primary productivity of 0.06 kg/m2/year, plankton account for 23.8% of Gouldsboro Bay and 16% of Dyer Bay primary productivity.

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Marine Ecosystem Analysis of Gouldsboro and Dyer Bays, Maine

Smithsonian Contributions to the Marine Sciences ◽

10.5479/si.11950329.v1 ◽

2020 ◽

pp. vii-192

Author(s):

Walter H. Adey ◽

Thew S. Suskiewicz ◽

Douglas B. Rasher

Keyword(s):

Primary Productivity ◽

Salt Marshes ◽

Gulf Of Maine ◽

Marine Ecosystem ◽

Google Earth ◽

Rocky Intertidal ◽

Saccharina Latissima ◽

Specific Productivity ◽

Rocky Subtidal ◽

Total Primary Productivity

In the early 1980s, the National Oceanic and Atmospheric Administration (NOAA) initiated an ecosystem analysis of Gouldsboro Bay in eastern Maine as part of a planned marine sanctuary. The original report to NOAA by Walter H. Adey was not published after the sanctuary concept for Maine was abandoned. Because significant human-related climatic and ecosystem changes are underway in the Gulf of Maine, that report provides valuable baseline data and is included as the Appendix to this volume. After qualitatively describing the geological, physical, chemical, and biogeographical features of Gouldsboro Bay and adjacent Dyer Bay, we quantitatively describe the principal bay ecological communities with data collected during the 1981–1983 ecosystem assessment as well as additional measurements taken within the past decade. We then undertake a comparison of the primary productivity of these bays with the Google Earth Pro polygon tool to determine component areas. Benthic taxa are the dominant primary producers in both bays: rockweeds (primarily Ascophyllum nodosum, with Fucus vesiculosus secondary) in the intertidal; Irish moss (Chondrus crispus, with Fucus distichus secondary) as a near monoculture in the lowest intertidal (infralittoral); kelps (primarily Saccharina latissima, Laminaria digitata, and Agarum clathratum) in the rocky subtidal; and the angiosperm Zostera marina (seagrass) in soft bottom substrate. The rocky intertidal, dominated by Ascophyllum with a specific productivity of 10.6 kg/m2/year, provides nearly one-third of all bay productivity. Because of the proportionally greater shore length relative to area of Dyer Bay, it has 45% greater productivity for its surface area than Gouldsboro Bay. Kelp has a specific productivity value of 7.2 kg/m2/year, and Zostera of 1.2 kg/m2/year. The kelps provide approximately 20% of Gouldsboro Bay’s primary productivity and 35% of that of Dyer Bay. Zostera provides roughly 20% of total primary productivity in Gouldsboro Bay and 12% in Dyer Bay. With a primary productivity of 1.73 kg/m2/year, salt marshes provide only 3.7% (Gouldsboro) and 2.6% (Dyer) of total primary productivity. With a primary productivity of 0.06 kg/m2/year, plankton account for 23.8% of Gouldsboro Bay and 16% of Dyer Bay primary productivity.

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EELS (Anguilla anguilla (L.)) OF THE LOWER RIVER SHANNON, WITH PARTICULAR REFERENCE TO SEASONALITY IN THEIR ACTIVITY AND FEEDING ECOLOGY

Biology & Environment Proceedings of the Royal Irish Academy ◽

10.3318/bioe.2007.107.2.87 ◽

2007 ◽

Vol 107 (2) ◽

pp. 87-94 ◽

Cited By ~ 6

Author(s):

P. Cullen ◽

T. K. McCarthy

Keyword(s):

Feeding Ecology ◽

Anguilla Anguilla

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Predicting bycatch hotspots based on suitable habitat derived from fishery-independent data

Marine Ecology Progress Series ◽

10.3354/meps13302 ◽

2020 ◽

Vol 641 ◽

pp. 159-175

Author(s):

J Runnebaum ◽

KR Tanaka ◽

L Guan ◽

J Cao ◽

L O’Brien ◽

...

Keyword(s):

Habitat Suitability ◽

Mixed Model ◽

Linear Mixed Model ◽

Gulf Of Maine ◽

Homarus Americanus ◽

Management Tool ◽

American Lobster ◽

Suitable Habitat ◽

Climate Conditions ◽

Suitability Index

Bycatch remains a global problem in managing sustainable fisheries. A critical aspect of management is understanding the timing and spatial extent of bycatch. Fisheries management often relies on observed bycatch data, which are not always available due to a lack of reporting or observer coverage. Alternatively, analyzing the overlap in suitable habitat for the target and non-target species can provide a spatial management tool to understand where bycatch interactions are likely to occur. Potential bycatch hotspots based on suitable habitat were predicted for cusk Brosme brosme incidentally caught in the Gulf of Maine American lobster Homarus americanus fishery. Data from multiple fisheries-independent surveys were combined in a delta-generalized linear mixed model to generate spatially explicit density estimates for use in an independent habitat suitability index. The habitat suitability indices for American lobster and cusk were then compared to predict potential bycatch hotspot locations. Suitable habitat for American lobster has increased between 1980 and 2013 while suitable habitat for cusk decreased throughout most of the Gulf of Maine, except for Georges Basin and the Great South Channel. The proportion of overlap in suitable habitat varied interannually but decreased slightly in the spring and remained relatively stable in the fall over the time series. As Gulf of Maine temperatures continue to increase, the interactions between American lobster and cusk are predicted to decline as cusk habitat continues to constrict. This framework can contribute to fisheries managers’ understanding of changes in habitat overlap as climate conditions continue to change and alter where bycatch interactions could occur.

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