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Recent food-web changes in the Laurentian Great Lakes are affecting energy and nutrient allocation to lake whitefish ( Coregonus clupeaformis) with potential downstream effects on egg condition and recruitment. We tested whether egg condition was conserved or varied with maternal condition in eight stocks from Lakes Erie, Michigan, and Superior. Egg condition was conserved across stocks based on ( i) a lack of correlation between females and eggs for total lipid, DHA, and other essential fatty acids; ( ii) higher levels of energy and long-chain polyunsaturated fatty acids (LC-PUFA) in eggs compared with females; and ( iii) no among-stock differences for those same variables in eggs. Females from northern Lake Michigan generally made the greatest trade-offs between egg size and fecundity. Highly fecund females provisioned less lipid, but more n-3 LC-PUFA to their eggs. A lack of stock-level patterns in energy and nutrient allocation suggests that trade-offs occur at the level of individual females and that females in poor condition make greater trade-offs among egg size and fecundity, total lipids, and n-3 LC-PUFA than females in good condition. [ABSTRACT FROM AUTHOR]

Proper data management (applying coordinated standards and structures to data collection, maintenance, retrieval, and documentation) is essential for complex projects to ensure data accuracy and accessibility. In this article, we used a recent project evaluating changes in Lake Whitefish (Coregonus clupeaformis) growth, condition, and recruitment in the Great Lakes as a case study to illustrate how thoughtful data management approaches can enhance and improve research. Data management best practices described include dedicating personnel to data curation, setting data standards, building a relational database, managing data updates, checking for and trapping errors, extracting data, documenting data sets, and coordinating with project collaborators. The data management actions taken ultimately resulted in a rich body of scientific publication and a robust database available for future studies. Investing in data management allowed this project to serve as a model for taking the first steps toward a common goal of sharing, documenting, and preserving data that are collected and reported during the scientific research process. RESUMEN: en proyectos complejos, un manejo apropiado de datos (aplicación coordinada de estándares y estructuras a recolección, mantenimiento, recuperación y documentación) resulta esencial para asegurar la precisión y accesibilidad de los mismos. En la presente contribución se utiliza un proyecto de evaluación de los cambios en el crecimiento, condición y reclutamiento del coregono en los Grandes Lagos, como caso de estudio para ilustrar cómo un manejo adecuado de datos puede incrementar y mejorar la investigación. Las mejores prácticas en cuanto a manejo de datos incluyen: dedicar personal a la curación de datos, fijar estándares en los datos, construcción de una base de datos relacional, manejo de actualización de datos, revisión y filtro de errores en los datos, extracción de datos, documentación de bases de datos y coordinación con colaboradores del proyecto. Las acciones de manejo de datos que se tomaron resultaron en la producción de un cuerpo importante de publicaciones y en una base de datos robusta, disponible para investigaciones futuras. Los recursos invertidos en el manejo de datos permitieron que este proyecto sirviera de modelo para tomar los primeros pasos hacia el objetivo común de compartir, documentar y preservar datos que son recolectados y reportados durante el proceso de una investigación científica. [ABSTRACT FROM AUTHOR]

We collected lake whitefish Coregonus clupeaformis and round whitefish Prosopium cylindraceum from the main basin of Lake Huron and Georgian Bay in the Laurentian Great Lakes of North America to investigate details of diet and feeding tactics of these species in different seasons. Lake whitefish supports important commercial fisheries in Lake Huron and both species make use of habitats near the Bruce Nuclear Power Development, on the eastern shore of Lake Huron. Most fish of both species showed generalist feeding behavior, but some lake whitefish appeared to show specialist prey selection. The invasive spiny water flea Bythotrephes longimanus was an important component of the diet of both species. There was considerable dietary overlap between the whitefish species, but the ecological implications of these dietary overlaps are mitigated by the fact that dominant prey species differed in most seasons. We conclude that the potential for ecologically significant interactions between lake whitefish and round whitefish resulting from competition for similar benthic food resources in the main basin of Lake Huron is probably low [Current Zoology 56 (1): 109–117 2010]. [ABSTRACT FROM AUTHOR]

Lake trout Salvelinus namaycush, lake whitefish Coregonus clupeaformis and cisco Coregonus artedi are salmonid fishes native to the Laurentian Great Lakes that spawn on rocky substrates in the fall and early winter. After comparing the locations of spawning habitat for these species in the main basin of Lake Huron with surficial substrates and the hypothesized locations of fast-flowing Late Wisconsinan paleo-ice streams, we hypothesize that much of the spawning habitat for these species in Lake Huron is the result of deposition and erosion by paleo-ice streams. This hypothesis may represent a new framework for the identification and protection of spawning habitat for these native species, some of which are currently rare or extirpated in some of the Great Lakes. We further suggest that paleo-ice streams may have been responsible for the creation of native salmonid spawning habitat elsewhere in the Great Lakes and in other glaciated landscapes. [ABSTRACT FROM AUTHOR]