Trophic analysis of two species of Atopsyche (Trichoptera: Hydrobiosidae)

Resource polymorphisms and competition for resources are significant factors in speciation. Many examples come from fishes, and cichlids are of particular importance because of their role as model organisms at the interface of ecology, development, genetics and evolution. However, analysis of trophic resource use in fishes can be difficult and time-consuming, and for fossil fish species it is particularly problematic. Here, we present evidence from cichlids that analysis of tooth microwear based on high-resolution (sub-micrometre scale) three-dimensional data and new ISO standards for quantification of surface textures provides a powerful tool for dietary discrimination and investigation of trophic resource exploitation. Our results suggest that three-dimensional approaches to analysis offer significant advantages over two-dimensional operator-scored methods of microwear analysis, including applicability to rough tooth surfaces that lack distinct scratches and pits. Tooth microwear textures develop over a longer period of time than is represented by stomach contents, and analyses based on textures are less prone to biases introduced by opportunistic feeding. They are more sensitive to subtle dietary differences than isotopic analysis. Quantitative textural analysis of tooth microwear has a useful role to play, complementing existing approaches, in trophic analysis of fishes—both extant and extinct.

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Trophic Analysis of Ruffe (Gymnocephalus cernuus) and White Perch (Morone americana) in a Lake Superior Coastal Food Web, Using Stable Isotope Techniques

Journal of Great Lakes Research ◽

10.1016/s0380-1330(96)70968-1 ◽

1996 ◽

Vol 22 (2) ◽

pp. 436-443 ◽

Cited By ~ 28

Author(s):

Michael E. Sierszen ◽

Janet R. Keough ◽

Cynthia A. Hagley

Keyword(s):

Stable Isotope ◽

Food Web ◽

White Perch ◽

Lake Superior ◽

Morone Americana ◽

Gymnocephalus Cernuus ◽

Isotope Techniques ◽

Trophic Analysis

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Phytoplankton size structure, distribution, and primary production as the basis for trophic analysis of Caribbean ecosystems

ICES Journal of Marine Science ◽

10.1093/icesjms/fsq182 ◽

2010 ◽

Vol 68 (4) ◽

pp. 751-765 ◽

Cited By ~ 6

Author(s):

Marie-Hélène Forget ◽

Trevor Platt ◽

Shubha Sathyendranath ◽

Paul Fanning

Keyword(s):

Primary Production ◽

Annual Cycle ◽

Size Structure ◽

Marine Ecosystem ◽

Chlorophyll Concentration ◽

Remotely Sensed ◽

Remotely Sensed Data ◽

Phytoplankton Size ◽

Trophic Analysis ◽

Phytoplankton Size Structure

Abstract Forget, M-H., Platt, T., Sathyendranath, S., and Fanning, P. 2011. Phytoplankton size structure, distribution, and primary production as the basis for trophic analysis of Caribbean ecosystems. – ICES Journal of Marine Science, 68: 751–765. An oceanographic survey was conducted in Caribbean waters in April and May 2006 to assess the marine ecosystem in the context of a trophic analysis of the foodweb. Analyses of pigment and absorption data revealed that the phytoplankton community was dominated by pico- and nanophytoplankton, particularly at the deep chlorophyll maximum. Based on cluster analysis of remotely sensed data, three dynamic provinces were defined for the region. A 5-year time-series of sea surface temperature and chlorophyll concentration provided information on the annual cycle of these properties. To implement the computation of primary production on a synoptic scale, parameters characterizing the biomass profiles and photosynthesis–irradiance relationships were assigned using four protocols: two regional approaches, a regression with surface chlorophyll, and the nearest-neighbour method (NNM), which has the advantage of assigning parameters on a pixel-by-pixel basis. Monthly images of primary production were computed over an annual cycle using MODIS chlorophyll a concentration. The NNM and the use of dynamic provinces emerged as the methods of choice for parameter assignment. Finally, a new approach from remotely sensed data was developed to estimate production-to-carbon ratios, a key input to Ecopath models. The results contribute to ecotrophic analysis of the Lesser Antilles Pelagic Ecosystem project.

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