Sustaining Aquatic Biodiversity FMS 2013 APES Chapter 13

Sustaining Aquatic Biodiversity FMS 2013 APES Chapter 13

Key Concepts Economic and ecological importance Effects of human activities Protecting and sustaining aquatic diversity Protecting and sustaining fisheries Protecting and restoring wetlands

Case Study: A Biological Roller Coaster Ride in Lake Victoria • Lake Victoria has lost its endemic fish species to large introduced predatory fish.

Case Study: A Biological Roller Coaster Ride in Lake Victoria 1980 s – 500 species of fish 80% were cichlids (algae eating fish with slightly different niches) 50% of Cichlid species have gone extinct since

A Biological Roller Coaster Ride in Lake Victoria • Reasons for Lake Victoria’s loss of biodiversity: – Introduction of Nile perch. – Loss of native cichlid species – Lake experienced algal blooms from nutrient runoff. – Invasion of water hyacinth has blocked sunlight and deprived oxygen. – Nile perch is in decline because it has eaten its own food supply.

AQUATIC BIODIVERSITY • We know fairly little about the biodiversity of the world’s marine and freshwater systems. • The world’s marine and freshwater systems provide important ecological and economic services.

The Importance of Aquatic Biodiversity • The most biologically diverse habitats include: – Coral reefs – Estuaries – Deep ocean floor – Huge diversity of habitats and food sources – Highest near the coast ( variety habitats and producers ) – 25, 000 fish species

The Importance of Aquatic Biodiversity: Ecological and Economic • Food Items – 6% of total protein; 16% of animal protein • Many Chemicals – Cosmetics • from seaweed – Medicines and Drugs • Antibiotics and anticancer drug, adhesives, bone reconstructive materials • seaweed, sponges, mollusks, coral barnacles, and other fish

Human Impacts on Aquatic Biodiversity • • • Species loss and endangerment Marine habitat loss and degradation Freshwater habitat loss and degradation Overfishing Nonnative species Pollution and climate change

Species Loss and Endangerment • • Overfishing Habitat destruction Pollution Freshwater species at greater risk – Mussels, crayfish, amphibians, fish

Marine Habitat Loss and Degradation • 53% of coastal wetlands in US have disappeared – Agriculture – Coastal development • 58% of world’s coral reefs are threatened – – – Coastal development Pollution Warmer ocean temperatures • Two-thirds of US estuaries are at risk from pollution • 35% of world’s mangroves have disappeared

Freshwater Habitat Loss and Degradation • The world has lost more than half of its inland wetlands – Agricultural and urban development • 60% of the world’s larger rivers are fragmented by dams, diversions, and canals • Flood control levees and dikes – Alter and destroy aquatic habitats – Disconnect rivers from their floodplains – Eliminate wetlands and backwaters (spawning areas)

Overfishing • 75% of the world’s 200 commercially valuable marine fish species are overfished • Overfishing leads to commercial extinction • Depletions and extinction of species unintentionally caught as bycatch

Non-native Species • Deliberate or accidental introduction into coastal waters, lakes and wetlands – – – purple loosestrife Asian swamp eel zebra mussle • Displace or cause extinction of native species – 68% of fish extinctions

Pollution and Climate Change • 44% comes from runoff from developed coastal areas • Major pollution threats – Oil – Acid deposition – Plant nutrients – Toxic chemicals – Coastal development – Sediment and soil erosion Climate Change could alter migration and feeding patterns increase ocean temperature raise sea levels

PROTECTING AND SUSTAINING MARINE BIODIVERSITY • Six of the world’s seven major turtle species are threatened or endangered because o human activities. Figure 12 -4

Protect endangered and threatened species • Example: Sea turtle – Turtle extrusion devices (TEDs) Olive ridley Loggerhead Leatherback Hawksbill Australian flatback Black turtle Green turtle Kemp's Ridley

Shrimp trawler Turtle Extrusion Device Area enlarged right

Case Study: The Florida Manatee and Water Hyacinths • Manatee can eat unwanted Water Hyacinths. • Endangered due to: – Habitat loss. – Entanglement from fishing lines and nets. – Hit by speed boats. – Stress from cold. – Low reproductive rate

Human Demand for Seafood is Outgrowing the Sustainable Yield for most Fisheries

Commercial Extinction When it is no longer profitable to continue fishing the affected species.

Domino Effect of Losing Cod Fishermen turned to fishing sharks Shark populations in the N. Atlantic declined by 99% Sharks are important apex predators that hunt rays and skates. Subsequently – ray and skate populations exploded, which caused a decline in Bay Scallops

Class Activity 4 groups: Trawlers, Purse Seine, Long Line, Drift Net

Commercial Whaling • Despite ban, Japan, Norway, and Iceland kill about 1, 300 whales of certain species for “scientific purposes”. – Although meat is still sold commercially.

Sucks to be a whale Whales are easy to kill because of their large size and that they need to come to the surface to breath. Overharvesting has driven the Blue Whale close to biological extinction

Blue Whales Continued….

What is Being Done? • 1946 – the IWC (International Whaling Commission) set out to regulate whaling • Set quotas to prevent overharvesting and commercial extinction. • Problem: No power of enforcement = ignored!

Case Study: Holding Out Hope for Marine Turtles Of the 7 species of marine turtles, 6 are either critically endangered or endangered. Example: Leatherback

Case Study: Holding Out Hope for Marine Turtles Leatherback Problems Survived for roughly 100 million years, but faces possible extinction Stable in Atlantic, but declined by 95% in Pacific Bottom trawlers are destroying the coral gardens that serve as their feeding grounds They are hunted for meat, leather, and eggs They drown in nets, on lines, and in traps They choke on plastic Artificial lights disorient hatchlings and end up predated Sea levels flooding nesting habitats and disrupt migration patterns

Case Study: Holding Out Hope for Marine Turtles How are we protecting them? Turning off lights during hatching season Nesting areas roped off Since 1991, US gov’t requires offshore shrimp trawlers to use turtle excluder devices (TEDs) that help keep sea turtles from being caught in nets or allow them to escape. In 2004, US gov’t banned long-lining for swordfish off Pacific coast to help save dwindling sea turtle populations there.

Case Study: Holding Out Hope for Marine Turtles How are we protecting them? Playa Junquillal, NW coast of Costa Rica, use ecotourism instead of selling turtle products. In 2004, volunteers and the WWF biologists, went out to find and rescue turtle nests in Costa Rica before they could be poached, and built hatcheries to protect the eggs. Prior, all nests were poached, a year later, none were poached.

Marine sanctuaries protect ecosystems and species �By international law, a country’s offshore fishing zone extends this far from its shores: � 370 km (200 nautical miles) �Foreign fishing vessels can take certain quotas of fish within such zones with the government’s permission called: �Exclusive economic zones �Ocean areas beyond such zones have laws and treaties pertaining to them, but they are hard to monitor and enforce. These areas are called: �The high seas

Marine sanctuaries protect ecosystems and species �Since 1986, the IUCN has helped to establish a global system of marine protected areas (MPAs)- areas of ocean partially protected from human activities. There are more than 4, 000 MPAs worldwide. �“Partially Protected” they still allow: �Dredging �Trawler fishing �Other ecologically harmful resource extraction activities

World MPAs

Marine sanctuaries protect ecosystems and species �However, In 2007, California began establishing the nation’s most extensive network of MPAs in which fishing will be banned or strictly limited.

California’s MPAs

Establishing a global network of marine reserves: an ecosystem approach to marine sustainability �The primary objective of this ecosystem approach is to protect and sustain the whole marine ecosystem for current and future generations instead of focusing primarily on protecting individual species.

Establishing a global network of marine reserves: an ecosystem approach to marine sustainability �Marine reserves are fully protected and off-limits to human activities to enable these areas to recover. �A global network would include large reserves on the high seas (near upwelling sites), and a mixture of smaller reserves in coastal zones (near commercial fishing areas). �Sites can be temporary or moveable (migrating species).

Establishing a global network of marine reserves: an ecosystem approach to marine sustainability �Studies show that within fully protected marine reserves, commercially valuable fish populations double, fish size grows by almost a third, fish reproduction triples, and species diversity increases by 25%. �These positive changes could happen within 2 -4 years and last for decades.

Establishing a global network of marine reserves: an ecosystem approach to marine sustainability �Reserves also help nearby fisheries because fish move in and out of reserve and larvae float on currents to fishing grounds.

Establishing a global network of marine reserves: an ecosystem approach to marine sustainability �In 2009, a group of Pacific island nations put 4 areas of international waters off limits to fishing to save world’s last great tuna stocks. �In 2008, Kiribati established a reserve the size of California between Fiji and Hawaii. �In 2006, the US created a large reserve NW of the Hawaiian Islands.

Establishing a global network of marine reserves: an ecosystem approach to marine sustainability �Despite all of this, less than 1% of the world’s oceans are in marine reserves and only 0. 1% fully protected. �Many marine scientists call for 30 – 50% protection with protected corridors between them. �In 2004, a study by a team of U. K. scientists showed it would cost the same as the subsidies that promote overfishing.

Some Marine Systems Can Be Restored �The example of reef restoration by a restaurant owner in Israel is an application of: �Reconciliation ecology �Another example is Japan attempting to restore its largest coral reef- 90% died- by seeding it with new corals. �Other ecosystems that could be restored: �Mangrove forests �Coastal marshes �Sea-grass beds

Protecting marine biodiversity requires commitments from individuals and communities �What can individuals and communities do? �Monitor and regulate fishing and coastal land development �Greatly reduce pollution from land-based activities �Think about what you put on your lawns and the kinds of waste generated �Choose sustainably harvested and farmed seafood �Reduce carbon footprint

Protecting marine biodiversity requires commitments from individuals and communities �One emerging strategy is a community based effort to develop and use coastal resources more sustainably and it is called: �Integrated coastal management �Australia manages its Great Barrier Reef Marine Park in this way. �US example: Chesapeake Bay Program

Protecting marine biodiversity requires commitments from individuals and communities �The overall aim of these programs is for fishers, business owners, developers, scientists, citizens, and politicians to identify shared problems and goals in their use of marine resources. �This requires short-term trade-offs!

Key Concepts Economic and ecological importance Effects of human activities Protecting and sustaining aquatic diversity Protecting and sustaining fisheries Protecting and restoring wetlands

11 -3: How Should We Manage and Sustain Marine Fisheries?

Estimating and monitoring fishery populations is the first step �There are many methods of estimating populations of fish and shellfish: � Maximum sustained yield (MSY) model � Maximum # of fish that can be harvested from a fish stock without causing the population to decline. � Optimum sustained yield (OSY) concept � Takes into account interactions between species � Multispecies Management approach � Takes into account predation and competition � Computer models for managing multispecies fisheries in large marine systems �There are uncertainties built into using any of these approaches, so environmental scientists suggest using the precautionary principle, closing some over-fished areas until they recover and we have more

Some communities cooperate to regulate fish harvests �Many fishing communities have developed allotment and enforcement systems for controlling fish catches in which each fisher gets a share of the total allowable catch. These are called: �Catch-share systems

Some communities cooperate to regulate fish harvests �With influx of large modern fishing boats, community management systems have been replaced by comanagement systems (communities and gov’t work together). �Here, gov’t sets quotas for species and divides among communities. May limit fishing season or type of gear used. Usually community manages inshore fisheries and the gov’t manages offshore.

Government subsidies can encourage overfishing �A 2006 study estimates the gov’t around the world give a total of about $30 – 34 billion per year in subsidies to fishers to keep businesses running. �Of that, $20 billion helps them buy ships, fuel, and fishing equipment, the remaining to research and management of fisheries. �Some argue that it encourages overfishing, resulting in too many boats chasing too little fish. �Some countries are using individual transfer rights (ITRs), or fish shares, you get a quota and can sell/lease your shares.

Consumer choices can help sustain fisheries and aquatic biodivesity �An important component of sustaining aquatic biodiversity and ecosystem services is bottom-up pressure from consumers demanding: �Sustainable seafood �Know how and where caught �Is it certified by the Marine Stewardship Council and have the eco-label “Fish Forever”? �Does it have a certified label of sustainable aquaculture or fish farming?

11 -4: How Should We Protect and Sustain Wetlands?

Coastal and inland wetlands are disappearing around the world �U. S. has lost more than half of its coastal and inland wetlands since 1900. �New Zealand has lost 92% of its original coastal wetlands �Italy has lost 95%

Coastal and inland wetlands are disappearing around the world �Drained, filled in, or covered over to create fields, cities, suburbs, and roads �Destroyed to extract minerals, oils, and natural gas, and to eliminate breeding grounds for insects that cause disease. �Rising sea levels

Coastal and inland wetlands are disappearing around the world �As of 2006 New Jersey is the 11 th most populated state in the nation, but the most densely populated, with 1, 174 residents per square mile. �Since the 1780's, the state has lost approximately 39% of it's wetlands, from an estimated 1, 500, 000 acres down to 915, 960 acres of wetlands in the 1980's. �Wetlands in New Jersey face significant pressures, including development and pollution; more than half of the 109 Superfund sites in New Jersey are adjacent to wetlands. �Despite a strong state program, wetlands are still being lost in New Jersey, at a rate of approximately 138 acres a year between 1988 and 2001, according to the NJ DEP.

We can preserve and restore wetlands �Zoning laws: �US requires a permit to fill in wetlands occupying more than 1. 2 hectares (3 acres) or to deposit dredged material on them. � Helped cut annual wetland loss by 80% since 1969 �Mitigation Banking is a policy that allows destruction of existing wetlands as long as an equal area of the same type is created or restored. � Difficult to do � Most restored wetlands fail or do not perform their ecological functions – However, Army Corp. of Engineers and private investors make huge profits failing! � Must be created or restored before existing wetlands destroyed

Case Study: Can We Restore the Florida Everglades? �Between 1962 and 1971, US Army Corps of Engineers straightened and built a canal on Kissimmee River �Work done to the river dried out much of the Everglades and then converted to farmland �Population increased; more development �Much of Everglades drained, diverted, paved over, polluted by agricultural runoff, and invaded by many species.

Case Study: Can We Restore the Florida Everglades? �Outcomes: �Everglades half the size �Vulnerable to summer wildfires � 90% of wading birds gone �Populations of vertebrates from deer to turtles down 75 -95% �Florida Bay now saltier and warmer due to diversion of fresh water for crops and cities �Algal blooms, sometimes covering 40% of the bay, due to nutrient output from farms and cities �Bay and Florida Keys coral reefs, diving, fishing, and tourism affected

Case Study: Can We Restore the Florida Everglades? �In 1990, Florida’s state gov’t and the US gov’t agreed on the world’s largest ecological restoration project known as the Comprehensive Everglades Restoration Plan (CERP).

Case Study: Can We Restore the Florida Everglades? �Goals of the plan: �Restore curving flow of Kissimmee River �Remove 250 miles of canals and levees blocking water south of Lake Okeechobee �Buy 93 sq mi of farmland allow it to be flooded �Create 18 large reservoirs and underground storage �Build new canals, reservoirs, and pumping systems to catch water flowing out to sea and return it to Everglades

Case Study: Can We Restore the Florida Everglades? �Plan is beginning to unravel � 2003, sugarcane growers convinced FL gov’t to increase amount of phosphorus and to extend deadline for reducing from 2006 to 2016 �Experienced cost overruns � Funding, esp. fed. Gov’t has fallen short �Far behind on almost every component of the project

Case Study: Can We Restore the Florida Everglades? �Bottom Line: �Prevention of environmental harm works better and is less costly then trying to undo it �When we intervene in nature, unitended and often harmful consequences usually result. �Classic case of where the precautionary principle should have been used!

11 -5: How Should We Protect and Sustain Freshwater Lakes, Rivers, and Fisheries?

Freshwater ecosystems are under major threats �Use HIPPCO � 40% of the world’s rivers have been dammed or otherwise engineered �Many of the world’s wetlands have been destroyed �Aquatic species have been crowded out of at least ½ of the world’s freshwater habitat areas �Invasive species, pollution, climate change threaten many ecosystems �Increasing human population and projected climate change make these matters worse

Case Study: Can the Great Lakes Survive Repeated Invasions by Alien Species? �The Great Lakes are the world’s largest body of fresh water. �Since the 1920 s, they have been invaded by at least 162 nonnative species �One of the biggest threats is the sea lamprey, a parasite of almost any fish, depleting many species, like trout �US and Canada use chemicals to kill sea lamprey larvae that costs $15 million per year

Case Study: Can the Great Lakes Survive Repeated Invasions by Alien Species? �Another invader: the zebra mussel from Europe from ballast water! �Has no known enemies in the Great Lakes �Displaced many mussel species and thus depleted food supply for other species �Clogged irrigation pipes, shut down water intake pipes, fouled beaches, jammed ships’ rudders, grown in huge masses on boat hulls, piers, pipes, rocks…everywhere! �Costs US and Canada $1 billion/year or $114, 000 per hour

Case Study: Can the Great Lakes Survive Repeated Invasions by Alien Species? �Another mussel: guagga mussel from Russia �Can survive greater depths and tolerate more extremes than zebra mussels �Have rapidly replaced many other bottom-dwellers in Lake Michigan, reducing food supply �It is now found all the way in the Colorado River and its reservoir system

Case Study: Can the Great Lakes Survive Repeated Invasions by Alien Species? �The Asian or grass carp brought up by catfish farmers from the south to help remove suspended matter and algae from their aquaculture farm ponds �Flooding released them into the Mississippi River �Have moved north to the Illinois River and some found in Lake Michigan �Prolific swimmers, voracious appetite, can jump/collide, have no natural predators

Managing river basins is complex and controversial �Rivers and streams’ ecological and economic services disrupted by: �Overfishing �Pollution �Dams �Water withdrawl for irrigation

Managing river basins is complex and controversial �Columbia River (runs through SW Canada and NW US) an example of this disruption �Has 119 dams (19 as hydroelectric power) and supplies water to major urban areas and large irrigation projects �Reduced populations of wild salmon by interfering with mature fish returning to spawn �Drop in population by 94% since dams were built � 9 species of salmon listed as endangered or threatened �Gov’t has spent $3 billion to save them to no avail

Managing river basins is complex and controversial �Snake River (State of Washington) another example of this disruption �Conservationists, native American tribes, and commercial salmon fishers want the gov’t to remove four small hydroelectric dams to restore salmon spawning habitat �Farmers, barge operators, and aluminum workers argue that removing the dams would hurt local economies by reducing irrigation water, eliminate shipping, and reducing supply of cheap electricity

We can protect freshwater ecosystems by protecting watersheds �Lakes and streams receive many of their nutrients from ecosystems of bordering land such as: from falling leaves, animal feces, and pollutants generated by people. �All these inputs are washed into bodies of water by rainstorms and melting snow. �Therefore, to protect rivers and streams, we must protect its watershed from excessive inputs.

We can protect freshwater ecosystems by protecting watersheds �In 1968, National Wild and Scenic Rivers Act �Wild rivers: those relatively inaccessible �Scenic rivers: those of great scenic value that are free of dams, mostly undeveloped, and only accessible in a few places �These rivers are protected from widening, straightening, dredging, filling, and damming �Only keeps 3% rivers free-flowing and 1% protected

Freshwater fisheries need better protection �Sustainable management involves �Supporting populations of commercial and sport fish species �Preventing such species from being overfished �Reducing or eliminating invasive species �Traditionally done by: �Regulate time and length of fishing seaons �Regulate the number and size of fish that can be taken

Freshwater fisheries need better protection �Other techniques: �Building, stocking, and protecting reservoirs and ponds with fish �Preventing sediment buildup and pollution �Controlling predators, parasites, and diseases by improving habitats, breeding genetically resistant fish varieties, using antibiotics and disinfectants �Hatcheries can also be used to restock bodies of water with fish

E. O. Wilson’s proposed priorities for protecting the world’s remaining ecosystems and species