AP PSYCHOLOGY

Detailed explanation-1: -Fish generally prefer larger shoals. This makes sense, as larger shoal usually provide better protection against predators. Indeed, the preference for larger shoals seems stronger when predators are nearby, or in species that rely more on shoaling than body armour against predation.

Detailed explanation-2: -Salmon must protect themselves from predators. They are particularly susceptible to predators when migrating so they seek deep pools for protection. In the ocean, some salmon stay together in a school, confusing predators with their flashy sides and causing them to be mistaken for a single large predator.

Detailed explanation-3: -The other highly notable adaptation in salmon is their gills. Atlantic Salmon have four sets of gills with specialized cells that allow them to migrate between salt and fresh water. The four sets also allow for efficient dissolving of oxygen.

Detailed explanation-4: -In the ocean, Atlantic salmon are eaten by: Large predatory fish like Atlantic halibut, Atlantic bluefin tuna, swordfish, and striped bass. Greenland shark, mako sharks, porbeagle sharks, and other sharks. Seabirds such as the Northern gannet.

Detailed explanation-5: -Threats. Threats to wild Pacific salmon include illegal harvest (poaching), habitat destruction from development and mining activities, dams and other blockages in rivers, unregulated overharvesting, and a rapidly changing climate.