The Role of Structure in the Physical Habitat of Anadromous Salmonids
نویسنده
چکیده
A fundamental difference between a canal and a natural stream is structure. Structure includes all the typical anomalies of natural streams that deflect the general downstream flow, such as bends, bars, bedrock knobs, boulders, landslide deposits, and large woody debris. This results in the storage of watershed products in the channel, and in a great heterogeneity in depth, velocity, stream gradient, and substrate conditions. In this paper, I will discuss these functions of structure in salmon habitat and some implications for restoration of habitat.
منابع مشابه
A Disturbance-Based Ecosystem Approach to Maintaining and Restoring Freshwater Habitats of Evolutionarily Significant Units of Anadromous Salmonids in the Pacific Northwest
-To preserve and recover evolutionarily significant units (ESUs) of anadromous salmonids Oncorhynchus spp. in the Pacific Northwest, long-term and short-term ecological processes that create and maintain freshwater habitats must be restored and protected. Aquatic ecosystems throughout the region are dynamic in space and time, and lack of consideration of their dynamic aspects has limited the ef...
متن کاملLinking Stream Carrying Capacity for Salmonids to Habitat Features
—Stream carrying capacity for anadromous salmonids that rear to the smolting stage in freshwater can be predicted from a sequence of cause-response functions that describe fish preferences for macro-habitat features. The channel unit (e.g., pool, glide, riffle) is a useful stratum for quantifying rearing capacity for salmonids, and is a hydrologically meaningful unit for predicting the response...
متن کاملEvolutionary consequences of habitat loss for Pacific anadromous salmonids
Large portions of anadromous salmonid habitat in the western United States has been lost because of dams and other blockages. This loss has the potential to affect salmonid evolution through natural selection if the loss is biased, affecting certain types of habitat differentially, and if phenotypic traits correlated with those habitat types are heritable. Habitat loss can also affect salmonid ...
متن کاملTrophic relationships of exotic anadromous salmonids in the southern Patagonian Shelf as inferred from stable isotopes
On the basis of their thermal preferences, salmon introduced in South America can distribute over the whole Southern Patagonian Shelf Ecosystem (SPSE). Stable isotope (d13C and d15N) data show that the SPSE is dominated by zooplanktivorous species (15 of 37), and its community is distributed over six trophic levels (TL), with salmonids occupying levels 4.2 to 4.9. A dual isotope mixing model wa...
متن کاملComparative transcriptomics of anadromous and resident brook charr Salvelinus fontinalis before their first salt water transition
Most salmonid taxa have an anadromous life history strategy, whereby fish migrate to saltwater habitats for a growth period before returning to freshwater habitats for spawning. Moreover, several species are characterized by different life history tactics whereby resident and anadromous forms may occur in genetically differentiated populations within a same species, as well as polymorphism with...
متن کامل