Balanites wilsoniana: Regeneration with and without elephants

Tropical forest trees that produce large fruits and/or large seeds are believed to be dependant on a few and often rare large vertebrates for dispersal. However, little is known about the population dynamics of such trees when they lose their specialised dispersers. This study examines the juvenile spatial distribution of Balanites wilsoniana, Dawe & Spraque, which is believed to be dependant solely on elephants for dispersal, in forests with and without elephants. Using camera traps, elephants were confirmed to be the only frugivores feeding and thus dispersing Balanites wilsoniana fruits. There was a high density of seedlings beneath adult trees in one forest without elephants, which was attributed to low seed and seedling predation in this forest. Nevertheless, it was only in the forest with elephants that juveniles were established away from adult trees. Analysis of the spatial distribution of these juveniles by size revealed that saplings and poles are more likely to be found away from adult trees thus providing evidence that dispersal enhances juvenile survival. This study underlines the importance of seed dispersal for trees that cannot maintain their populations through seedlings germinating and surviving beneath adult conspecifics. The study also demonstrates that loss of vertebrates has ramifications for tree species dynamics above and beyond loss of seed dispersers.     

Die Nutria als Pelztier

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Stream types in Idaho: An approach to classification of streams in natural areas

Five types among small streams are described: ephemeral streams, spring streams, and three types among permanent streams. Key features used to designate stream type are order, gradient, pattern of flow, and substrate which are readily identifiable, nonvariable characteristics. Type designation is supported on an ecological basis by analysis of extensive collections of aquatic plants and invertebrates.     

A methodology for the selection of aquatic natural areas

A methodology is presented for selection of aquatic natural areas based on numerical ranking of sites. Non-weighted points are assigned to 24 physical and biological characteristics of the aquatic and terrestrial components of a proposed natural area. Cumulative score reflects both natural diversity and occurrence of unusual species or conditions. A systematic selection procedure is described which can be utilised by land managers or natural area organisations to arrive at and support objective decisions involving natural area selection.     

Senior and geriatric care programs for veterinarians.

Earlier detection allows earlier intervention, and thus improved treatment success. Senior profiling improves anesthetic safety by identifying hidden existing diseases and permitting the postponement of anesthesia or altering the anesthetic plan. Furthermore, pharmaceutic safety is increased through the detection of underlying diseases that may preclude the use of certain drugs or suggest new alternative treatments. Many dietary recommendations are based on disease diagnosis, making senior profiling an important dietary database. Finally, earlier disease management by means of improved anesthetic, pharmaceutic, and dietary recommendations offers our patients and clients the best medical management possible.