Freshwater fishFreshwater fish are those that spend some or all of their lives in fresh water, such as rivers and lakes, with a salinity of less than 1.05%. These environments differ from marine conditions in many ways, especially the difference in levels of salinity. To survive fresh water, the fish need a range of physiological adaptations. 41.24% of all known species of fish are found in fresh water. This is primarily due to the rapid speciation that the scattered habitats make possible.
Spawn (biology)Spawn is the eggs and sperm released or deposited into water by aquatic animals. As a verb, to spawn refers to the process of releasing the eggs and sperm, and the act of both sexes is called spawning. Most aquatic animals, except for aquatic mammals and reptiles, reproduce through the process of spawning. Spawn consists of the reproductive cells (gametes) of many aquatic animals, some of which will become fertilized and produce offspring.
Wildlife corridorA wildlife corridor, habitat corridor, or green corridor is an area of habitat connecting wildlife populations separated by human activities or structures (such as roads, development, or logging). This allows an exchange of individuals between populations, which may help prevent the negative effects of inbreeding and reduced genetic diversity (via genetic drift) that often occur within isolated populations. Corridors may also help facilitate the re-establishment of populations that have been reduced or eliminated due to random events (such as fires or disease).
Saltwater fishSaltwater fish, also called marine fish or sea fish, are fish that live in seawater. Saltwater fish can swim and live alone or in a large group called a school. Saltwater fish are very commonly kept in aquariums for entertainment. Many saltwater fish are also caught to be eaten, or grown in aquaculture. However, many fish species have been overfished and are otherwise threatened by marine pollution or ecological changes caused by climate change. Fishes that live in the ocean can be carnivores, herbivores, or omnivores.
Fish mealFish meal is a commercial product made from whole wild-caught fish, bycatch, and fish by-products to feed farm animals, e.g., pigs, poultry, and farmed fish. Because it is calorically dense and cheap to produce, fishmeal has played a critical role in the growth of factory farms and the number of farm animals it is possible to breed and feed. Fishmeal takes the form of powder or cake. This form is obtained by drying the fish or fish trimmings, and then grinding it. If the fish used is a fatty fish it is first pressed to extract most of the fish oil.
Insular biogeographyInsular biogeography or island biogeography is a field within biogeography that examines the factors that affect the species richness and diversification of isolated natural communities. The theory was originally developed to explain the pattern of the species–area relationship occurring in oceanic islands. Under either name it is now used in reference to any ecosystem (present or past) that is isolated due to being surrounded by unlike ecosystems, and has been extended to mountain peaks, seamounts, oases, fragmented forests, and even natural habitats isolated by human land development.
SalmonSalmon (ˈsæmən; : salmon) is the common name for several commercially important species of euryhaline ray-finned fish from the family Salmonidae, which are native to tributaries of the North Atlantic (genus Salmo) and North Pacific (genus Oncorhynchus) basin. Other closely related fish in the same family include trout, char, grayling, whitefish, lenok and taimen. Salmon are typically anadromous: they hatch in the gravel beds of shallow fresh water streams, migrate to the ocean as adults and live like sea fish, then return to fresh water to reproduce.
Sustainable landscape architectureSustainable landscape architecture is a category of sustainable design concerned with the planning and design of the built and natural environments. The design of a sustainable landscape encompasses the three pillars of sustainable development: economic well-being, social equity and environmental protections. The United Cities and Local Governments, UNESCO, and the World Summit on Sustainable Development further recommend including a fourth pillar of cultural preservation to create successful sustainable landscape designs.
Edge effectsIn ecology, edge effects are changes in population or community structures that occur at the boundary of two or more habitats. Areas with small habitat fragments exhibit especially pronounced edge effects that may extend throughout the range. As the edge effects increase, the boundary habitat allows for greater biodiversity. Urbanization is causing humans to continuously fragment landscapes and thus increase the edge effect. This change in landscape ecology is proving to have consequences.
