Marine Biology Lets name the zone The zones

Marine Biology • “Let’s name the zone. . The zones… • http: //www. youtube. com/watch? v=ufx. Gw 8 Eq. Y 5 Q&safe=active

Major Ocean Life Zones

Intertidal • Intertidal Zone: – The area of shoreline between the low and high tides – Stressful, biologically productive habitat – Sandy beaches: • Constantly shifting environment, little protection against waves – Rocky shores: • Good anchorage for seaweeds and animals, but exposure to wave action at high tides; temperature fluctuations and drying out at low tides • Inhabitants have adaptations to drying out

Intertidal

Benthic • The Benthic Environment – The ocean floor, which extends from the intertidal zone to the deep ocean trenches – Consists of sediments (sand mud) – Burrowing animals • Bacteria, worms, clams, etc. – Three zones: • Bathyal (shallowest) • Abyssal • Hadal (deepest)

Major Ocean Life Zones

Coral Reefs • Benthic Environment: – Corals: soft-bodied animals, similar to jellyfish • • Live in hard cups or shells of calcium carbonate Accumulated skeletons produce coral reefs Found in warm, shallow waters Require light for symbiotic zooxanthellae Also capture food with stinging tentacles High productivity even in poor nutrient waters Most diverse marine environment - 100 s of species Ecologically important as habitat and protect coastlines form erosion • Provide humans with foods, pharmaceuticals, recreation

Coral Reefs

Coral Reefs

Sea Grass Beds • Benthic Environment – Sea Grasses • • • Flowering plants adapted to live in sea water Require shallow water for photosynthesis Quiet temperate, subtropical, and tropical waters High primary productivity Ecologically important: – Stabilize sediments, reduce erosion, provide food and habitat for marine organisms

Sea Grass Beds

Kelp Forests • Benthic Environment – Kelps • • Largest and most complex of all seaweeds Brown algae, Common in cooler temperate marine waters Especially abundant in relatively shallow waters along rocky shores • Primary food producers for kelp forest ecosystem • Provide habitat for many marine organisms: – Tubeworms, sponges, sea cucumbers, clams, crabs, fishes, sea otters • Very diverse ecosystem

Kelp Forests

Problems in the Kelp Forests • Otters in Trouble – Sea urchins feed on kelp otters feed on sea urchins kelp is maintained – Sea otter population in Alaska has had a 90% decline since 1990 • Sea urchin populations are exploding, devastating kelp forests • Killer whales typically feed on seals and sea lions, but those populations have declined, so now feed on otters • Starting point is possibly decline in fish stocks caused by overfishing/climate change • Terrestrial food chains have also been affected

Sea Otters- Keystone Species

Neritic Province • The Neritic Province – Part of the pelagic environment that overlies the ocean floor from the shoreline to a depth of 200 meters – Organisms are floaters (plankton) or swimmers (nekton) – Euphotic Zone: upper level of neritic zone • • • Sufficient light to support photosynthetic organisms Phytoplankton are basis of food webs Zooplankton feed on phytoplankton Plankton-eating nekton consumes zooplankton Carnivorous nekton consumes plankton-eating nekton

Floaters and Swimmers

Oceanic Province • The Oceanic Province – The part of the pelagic environment that overlies the ocean floor at depths greater than 200 m – Largest marine environment (75% of water) – Loosely described as ‘deep sea’ – Cold waters, high pressure, no light – Life adapted to darkness and scarce food • Drifting or slow swimming, reduced bone & muscle mass • Light producing organs to locate mates or prey • Depend on ‘marine snow’ (organic debris form upper layers of ocean) • Filter feeders, scavengers, predators • Many large invertebrates, e. g. , giant squid

Deep Sea Life

Global Climate Change 1. What are the four main life zones in the ocean, and how do they differ from one another? 2. Finish Deep Sea Planet Earth

Day 3

Case Study: Depleting Bluefin Tuna Stocks – Being fished at 4 times the sustainable level – Economic value places it in danger – Conservation measures protect the species – Overfishing • • Harvesting of fishes faster than they can reproduce 30% of worldwide fishes 80% of commercial fish stocks in US If overfishing and pollution aren’t curbed, populations of all harvested seafood species will be gone by 2048

Human Impacts on the Ocean • Learning Objectives: 1. Contrast fishing and aquaculture and relate the environmental challenges of each activity 2. Identify the human activities that contribute to marine pollution and describe their effects 3. Explain how global climate change could potentially alter the ocean conveyor belt

Human Impacts on the Ocean • • Fisheries and aquaculture Marine shipping Marine pollution Coastal development Offshore mining Global climate change In 2008, less than 4% of ocean remained unaffected by human activities; 41% serious harm

Human Impacts on the Ocean • Marine Pollution and Deteriorating Habitat – Paradox: ocean provides food but is used as dumping ground – Pollution increasingly threatens fisheries – 80% of ocean pollution comes from land activities

Human Impacts on the Ocean

Human Impacts on the Ocean

Human Impacts on the Ocean • World Fisheries – Valuable food resources • 90% of world’s catch is fishes, • 6% is clams, oysters, squid, octopus, and other molluscs • 3% is crustaceans: lobsters, crabs, shrimp • 1% is marine algae – World’s Annual Harvest • 1950 - 19 million tons • 2004 - 95 million tons

Human Impacts on the Ocean • Problems and Challenges for the Fishing Industry – No nation has legal claim to open ocean • Resources are susceptible to overuse and degradation (Tragedy of the Commons) – Many species have been harvested to the point where their numbers are severely depleted • Unstable for marine species that rely on them as part of food web • At least 75% of world’s fish stocks are exploited, overexploited or depleted – Growing human population requires protein – Technological advances allows efficient catch, removing all fish from an area – 25% of all is bycatch (unintentionally caught, then discarded)

What a Scientist Sees

Human Impacts on the Ocean • Aquaculture – Fish farming: growing of aquatic organisms for human consumption • Fresh and marine water • HDCs harvest more from open ocean • Developing nations harvest more from aquaculture – Abundant supply of cheap labor – Limit to harvest is the area available for farming • Fish farms have dense populations – Lots of polluting waste – Cause net loss of wild fish (raised fish tend to be carnivorous) – Ocean ranching: deep-water, off-shore aquaculture • Doesn’t harm coastline, but less oversight

Human Impacts on the Ocean

Human Impacts on the Ocean • Shipping, Ocean Dumping, Plastic Debris – Millions of ships dump oily ballast and waste – MARPOL bans marine pollution from shipping industry • Not well enforced – Ocean Dumping Ban Act • Cities used to dump sewage into ocean, diseasecausing organisms contaminated shellfish – Plastic waste • • Doesn’t degrade, just breaks up into smaller pieces Pacific Garbage Patch, 2009, 2 x size of Texas Plastic pieces entangle marine mammals and birds Filter feeders ingest plastic pieces, carriers of PCBs

Human Impacts on the Ocean

Human Impacts on the Ocean • Coastal Development – Alters or destroys coastal ecosystems: • Mangroves, salt marshes, sea grass beds, coral reefs – Coastal areas overdeveloped, highly polluted, overfished – Coastal management plans are inadequate • Biggest problem is human population size • 60% of world’s population lives within 150 km (93 mi) of coastline • As much as 75%, by 2025

Human Impacts on the Ocean • Human Impacts on Coral Reefs – 25% of world’s corals are at high risk • Silt washing downstream from clear-cut forests is smothering reefs • High salinity from freshwater diversion projects • Overfishing of top predators • Damage by tourists • Pollution from ocean dumping and coastal pollution • Bleaching = stressed corals expel zooxanthellae

What a Scientist Sees

Human Impacts on the Ocean • Offshore Extraction of Mineral and Energy Resources – Large deposits of minerals lie under the sea floor • Manganese nodules – mining would adversely affect sea life and market value would not cover expense of mining – Disputes over deposits under international waters • Petroleum – Major source of energy – Major threat to fishing

Human Impacts on the Ocean

Human Impacts on the Ocean • Climate Change – Incomplete understanding, unanticipated effects • There could be a disruption of the ocean conveyor belt, which transports heat around the globe • Climate warming could shut down conveyor belt within a decade – Could cause major cooling in Europe – Major warming in other parts of the world – Would not sequester CO 2 into ocean more CO 2 in atmosphere more warming more weakening of belt

Global Climate Change 1. What are some of the harmful environmental effects associated with the fishing industry? With aquaculture? 2. How does the widespread use of plastics contribute to ocean pollution? 3. How might the effect of global climate change on the ocean alter the global climate?

Addressing Ocean Problems • Learning Objectives: 1. Describe international initiatives that address problems in the global ocean 2. Explain goals associated with correcting ocean problems in the future

Addressing Ocean Problems • Problems are complex and require complex solutions – UN Convention on the Law of the Sea (UNCLOS) 1994 - 157 countries have ratified • Protecting ocean resources – UN fish stocks agreement - 1995 • Regulates marine fishing – Fishery Conservation and Management Act - 1977 • Protect essential fish habitat for 600 species • Reduce overfishing, rebuild populations, minimize bycatch • Fishing quotas, restrictions on fishing gear, limits on number of fishing boats, closure of fisheries during spawning

Addressing Ocean Problems • Future Actions – US Commission on Ocean Policy-2004 report • Create a new ocean policy to improve decision making– Consolidate agencies • Strengthen science and generate information for decision makers – Need for high quality research • Enhance ocean education to instill in citizens a stewardship ethic – Environmental education should be part of the curriculum at all levels, including strong marine component

Addressing Ocean Problems • Future Actions – Establishment of “no-take” reserves – Substantial reduction of fishing fleet – Remove subsidies of fishing industry – Adopt an ecosystem-based approach to manage ocean environments • Focus on preserving the health and function of the entire marine ecosystem • Establish networks of fully protected marine reserves • Less than 5% of US marine environments have been protected, with great success

Addressing Ocean Problems

Case Study • The Dead Zone in the Gulf of Mexico – N and P runoff from Mississippi river • Algae grow rapidly, dead algae sink to bottom and decompose, deplete water of O 2 (hypoxic zone) – Only anaerobic bacteria thrive there – March to September, worst June-August – Climate change is making dead zones worse, even without runoff • Threaten biodiversity and coastal fisheries

Case Study

Global Climate Change 1. Which international treaties aim to protect ocean resources? 2. What are the main goals recommended by the US Comission on Ocean Policy?

Major Ocean Life Zones • Marine environment is divided into zones: – Intertidal zone – Benthic (ocean floor) zone – Pelagic (ocean environment) zone • Neritic – From shore to 200 m (650 ft) depth • Oceanic – Depth greater than 200 m, beyond continental shelf

Quick Pop Quiz- just 2 and 4. 1. Describe the El Nino event and what effect it has on global weather. 2. Name two zones in the ocean. 3. Describe what the TAO/TRITON array do. 4. Where are most coral reefs located? (Think latitude. )