Marine Biology Latest Update with Certified Solutions

Marine Biology Latest Update with Certified Solutions The coastal zone the warm, nutrient-rich, shallow water that extends from the high-tide mark on land to the gently sloping, shallow edge of the continental shelf. Makes up less than 10 percent of the world's ocean area but contains 90 percent of all marine species. Provides numerous ecological and economic services. Subject to human disturbance. Estuaries where rivers enter the ocean. include river mouths, inlets, bays, sounds, salt marshes, and mangrove forests. salt marshes some of the most productive habitats on Earth. Serve as fish nurseries. Submerged aquatic vegetation also tremendously productive and important to fisheries. SAV is disappearing from estuaries worldwide, mostly due to nutrient pollution. Mangrove forests found along gently sloping sandy and silty coastlines. Protect coastlines, support fisheries, filter out wastes. Over 1/3 have been destroyed for shrimp farms, agriculture, and development. Kelp forests bring in species from the open seas. An economically important species is the red abalone. Urchins eat the kelp. Sea otters eat the urchins. Without otters, kelp beds decline. Coral reefs less than 0.2 percent of the ocean, yet tons of species live there. Half of the ocean's total biodiversity. High productivity in a nutrient desert. Coral are bleached when they lose their zooxanthellae. The deep sea cold, dark, big, pressure and little to eat. below 400 meters. Mesopelagic, bathypelagic, bathyal, abyssal, hadal. Mesopelagic 200-1000m. Animals are small, huge eyes, large jaws and teeth, bioluminescence and countershading. daily vertical migrations. The bioluminescence is a symbiotic bacteria. Predator avoidance. Species recognition. prey attraction. Mate attraction. lights on underside make fish less visible from below, against the surface. vertical migrations gas bladder bearing fish and large invertebrates. Link between surface and deep ocean. Bathypelagic Realm m. Gulper eel can eat fish as large as itself. Angler fish, males attach to female. Males are dwarfed. going deeper lower biomass, abundance. slow growing, long lived. fewer filter feeders, more deposit feeders and motile scavengers. deep sea floor mud and clay dominated, or formed by biological deposits. Hydrothermal vents are oases of life. Symbiotic chemoautotrophs are base of food web. adaptations to extremes in temperature. Bob ballard discovered hydrothermal vent communities by accident, while on a geology research cruise. discoverer of titanic. Chemosynthetic bacteria In total darkness, use chemical energy to fix carbon, produce food. Take home messages Mostly cold, dark, immense pressure and little to eat but far from lifeless. Largest habitat on the planet. Oasis driven by geothermal energy fueling chemosynthetic symbionts.