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In marine environments, a nursery habitat is a subset of all habitats where juveniles of a species occur, having a greater level of productivity per unit area than other juvenile habitats (Beck et al. 2001). Mangroves, salt marshes and seagrass are typical nursery habitats for a range of marine species. Some species will use nonvegetated sites, such as Yellow Eyed Mullet, Blue Sprat and Flounder. ==Overview== The nursery habitat hypothesis states that the contribution per unit area of a nursery habitat is greater than for other habitats used by juveniles for the species. Productivity may be measured by density, survival, growth and movement to adult habitat (Beck et al. 2001). There are two general models for the location of juvenile habitats within the total range for a species which reflect life history strategies of the species. These are the Classic Concept: Juveniles and Adults in separate habitats. Juveniles migrate to adult habitat. General Concept: overlap of juvenile and adult habitats. Some marine species do not have juvenile habitats, e.g. arthropods and scallops. Commonly fish, ells, some lobsters, blue crabs (and so forth) do have distinct juvenile habitats, whether with or without overlap with adult habitats. In terms of management, use of the nursery role hypothesis may be limiting as it excludes some potentially important nursery sites. In these cases the Effective Juvenile Habitat concept may be more useful. This defines a nursery as that which supplies a higher percentage of individuals to adult populations. Identification and subsequent management of nursery habitats may be important in supporting off shore fisheries and ensuring species survival into the future. If we are unable to preserve nursery habitats, recruitment of juveniles into adult populations may decline, reducing population numbers and compromising the survival of species for biodiversity and human harvesting. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Nursery habitat」の詳細全文を読む スポンサード リンク
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