Expert Group Instructions

1. Read the article assigned to your group. You may take notes by underlining or highlighting important information.

2. Discuss with your expert group the following key questions about the ways humans can alter the ocean system:

Describe how humans are altering the ocean system, including the specific parts of the ocean system that are affected.

Is this a positive change to the ocean system or a negative change? Why?

How/Why are humans responsible for this? If the change is negative, can this be prevented? How? Is this change in the ocean system reversible or permanent?

3. AS A GROUP , Create a rough draft of a poster that summarizes the answers to the questions above. You may use illustrations, diagrams, or graphic organizers to communicate the information.

4. After teacher approval, obtain a sheet of chart paper and create a final draft of your poster. Hang your poster in the classroom.

Home Group Instructions

1. Obtain a copy of “Ocean Resources Content Frame” for each group member.

2. Participate in a gallery walk of the posters with your home group. 3. At each poster, the “Expert” that participated in the creation of

the poster will teach the group the important points on the poster.

4. Each group member is responsible for recording the information in their content frame.

** IMPORTANT: Ask the teacher questions if needed!!

Runoff Pollution1

It’s a beautiful Saturday—a perfect day to make some extra spending money washing cars for family and neighbors, gassing up and oiling the lawn mower, laying down some fertilizer on those yellow patches in the yard, walking the dog, and spraying your mom’s rosebushes for pesky bugs. The health of your nearby stream is probably one of the last things on your mind as you tackle your tasks. But guess what! Each of your jobs could harm a nearby stream, lake, or wetland. How? Well, consider.... Many cleaning products used in washing cars contain phosphates and other chemicals that can make fish and other aquatic life sick. Using a hose to wash off suds creates a stream of wastewater that can travel down your driveway, into the street, and down a storm drain. No prob? Well, what do you think is at the other end of your storm drain? Usually a stream!

Working with MotorsMotors must be maintained if you want them to work properly. Oil, gasoline, brake fluid, degreasers, and antifreeze are a few of the products you need. All of these products contain chemicals that can harm aquatic life if they get into a stream, lake, or wetland. One gallon of used oil can ruin a million gallons of fresh water—a year’s supply for 50 people. If you accidently spill these products on the ground when you’re working, the next rainstorm will pick them up and carry them to the nearest stream.

Some chemicals can cause immediate harm or death to insects, fish, and animals within 96 hours or less (for example, antifreeze, which is toxic to pets, has a sweet taste that cats and dogs love). Others cause harm over time.

Fertilizing the LawnGreen lawns need lots of fertilizer,

right? Wrong! Too much fertilizer applied at the wrong time can cause disease, weeds, and poor root growth. Too much fertilizer can make your lawn less able to withstand heavy rain or dry weather. In addition, rain can also pick up excess fertilizer and carry it to a lake or stream. This fertilizer causes algae and weeds grow in the water.

Walking the DogDon’t be embarrassed to say it—pet poop is potential pollution. Pet feces contain a lot of bacteria that can contaminate streams, lakes, and ponds. One study found that a single gram of dog feces contains 23 million fecal coli form bacteria. In addition, pet poop contains nitrogen and phosphorus; two elements that fertilize algae and other aquatic plants and make them grow out of control.

Do you know…the difference between a storm drain and a

sewer? Storm drains collect water from outside our homes and businesses and carry it, untreated, directly to streams and rivers. Sewers collect water from inside homes and businesses and carry it to treatment plants,

where it is cleaned before it reaches streams and rivers. Only rain should go into storm drains, not trash, oil, or other pollutants.

Controlling Insect PestsPests are a pain, but getting rid of

them can be a greater pain if you do it wrong. Using harsh pesticides can be harmful for people and the environment. According to the Federal Centers for Disease Control, 82 % of Americans already have a widely used insecticide in their bodies called Dursban. A technique known as integrated pest management is the best approach to controlling pests and protecting waterways from pollution. Chemical insecticides are used in moderation, if at all. The focus is on early identification of pests and natural controls

such as introducing predators to feed on the pests and planting plants that are naturally resistant to pests.

Let’s talk facts!

Runoff pollution includes many small sources, like septic tanks, cars, trucks and boats, plus larger sources, such as farms, ranches and forest areas. 80% of pollution to the marine environment comes from land-based sources. Millions of motor vehicle engines make daily, one-drop-at-a-time "oil spills" onto roads and parking lots, which significantly add to runoff pollution. Some water pollution actually starts as air pollution, which settles into waterways and oceans.Top soil or silt from fields or construction sites can run off into waterways, harming fish and wildlife habitats. “Non-point source pollution”, commonly called runoff pollution, can make river and ocean water unsafe for humans and wildlife. Drinking water supplies can be contaminated by polluted runoff, as can coastal waters containing valuable fish stocks. Experts think there is a link between agricultural runoff and water-borne organisms that cause lesions and death in fish (Pfisteria). Humans who come in contact

with these polluted waters and affected fish can also experience harmful symptoms. More than one-third of the shellfish-growing waters of the United States are adversely affected by coastal pollution. Correcting the harmful effects of runoff pollution is costly. Each year millions of dollars are spent to restore and protect areas damaged or endangered by non-point source pollutants.

A rtificial Reefs: Oases for Marine Life in the Gulf 2 Whether it’s an operating oil and gas (petroleum) production platform or a retired platform intentionally placed for conservation and fisheries enhancement, a typical 4-pile platform jacket (the underwater support structure of an offshore platform) provides 2-3 acres of living and feeding habitat for thousands of underwater species.

That’s a good thing, because the natural bottom of the Gulf of Mexico (GOM) is a flat plain, comprised of mud, clay and sand with very little natural rock bottom and reef habitat. Without the platform and other artificial reefs, fish and other marine life typically would become widely dispersed, far from ideal conditions for commercial fishing and recreational fishing and diving.

Invertebrates and plants attach to petroleum platforms within weeks of their placement in the marine environment. Within a year, the platform can be completely covered with plants and invertebrates, attracting mobile invertebrates and fish species, and forming a highly complex food chain.

Petroleum platforms function as completely new places to live; niches for countless animals. In addition to harboring many species of fish, these platforms serve as hunting grounds for quick moving fish that live in the open ocean, such as mackerel and tuna. These fish species use the steel platform reefs as places to grab a quick meal, as areas to rest where the platform structure weakens or deflects currents, and as places to hide from species that may prey on them. Marine researchers have reported fish population densities to be 20 to 50 times higher at oil and gas platforms than in nearby open water. Each platform can serve as a critical habitat for 10,000 – 20,000 fish, many of which are of recreational and commercial importance.

Retired petroleum platforms are required to be removed from the marine environment and taken to shore for disposal within one year from termination of the oil and gas lease. An alternative to onshore disposal is the conversion of retired platforms to permanently submerged artificial reefs, i.e. Rigs-to-Reefs (RTR).

Three methods for removing and reefing a platform are used in the RTR process.

1. Platform Tow and Place

2. Platform Topple in Place

3. Platform Partial Removal

At the end of 1998, 1,715 platforms were retired from oil and gas production, 128 of the retired platforms were donated and permanently dedicated as RTR for fisheries enhancement. Recreational charter boat captains, fishermen, and divers from across the Gulf have all firmly established oil and gas platforms and RTR as the most popular offshore fishing and diving destinations in the GOM.

The use of retired and obsolete oil and gas platforms for reefs has proved to be highly successful. State governments, the oil and gas industry, and the commercial and recreational fishermen, have all been beneficiaries of RTR. Their large numbers, availability, stability, and durability has made offshore oil and gas platforms and RTR the largest artificial reef complex in the world.

Content FrameHow can the

ocean system be altered?

DescriptionPositive (+) or Negative (-)

change?

How/Why are humans responsible for this?

Can this be prevented? How?

Runoff pollution

Artificial Reefs

Sound impact

Marine Debris

Overfishing

Oil spills

Boat noise that is within the audible range of marine mammals, such as these killer whales, may prevent them from hearing important sounds. Photo ©Tom Kieckhefer

Sound Impact on Marine Animals3

Water is an effective medium for the transmission of sound, therefore both marine animals and people use sound as a tool for finding objects, navigating, and communicating under water. Many marine animals rely on sound for survival and depend on adaptations that enable them to sense their surroundings acoustically, communicate, locate food, and protect themselves under water. Some recent research suggests that increased background noise and specific sounds might affect marine animals in several ways. Sounds may cause marine animals to:

Alter their behavior, such as changes in movement, breathing patterns, and vocalizations Prevent marine animals from hearing important sounds (called masking) Become stranded Cause hearing loss (temporary or permanent), or damage tissue.

Behavioral Changes

Marine animal responses to sound can vary from the simple turn of a head or more significant changes such as subtle changes in diving, surfacing, vocalization patterns or even a change in habitat use. In a study of beluga whales conducted in an area of frequent boat traffic, the beluga whales stopped feeding and rapidly swam away from approaching ice-breaking vessels. The whales traveled up to 80 km away from productive feeding areas and remained there for 1-2 days before returning.

Some of the strongest behavioral reactions occur when the sounds are similar to those made by predators. Harbor seals responded to playbacks of mammal-eating killer whales and unfamiliar fish-eating killer whales, but did not respond to familiar calls of fish-eating killer whales. This also suggests that animals can become accustomed to sounds that appear harmless by learning from previous experiences and stop responding to them.

Masking

Masking occurs when a loud sound drowns out a softer sound or when noise is at the same frequency as a sound signal, interfering with a marine animal's ability to hear a sound of interest. Just as it can be difficult to hear someone talking at a loud party, high noise levels in the ocean may interfere with marine animals' ability to hear important sounds. Animals may try to minimize masking by changing their behavior. Just as you may talk more loudly to be heard at a party, animals may use louder calls. These behavior changes may also include producing more calls, longer calls, or shifting the frequency of the calls.

The effects of noise on the vocal behavior of beluga whales in the St. Lawrence River Estuary have been studied. This region is both a main route for commercial shipping and a popular location for whale watching. Beluga whales live in the region year-round. Researchers found that when exposed to noise from a small motorboat and from a ferry; belugas reduced their calling rate as the boats were approaching, but then increased the repetition of

certain calls when boats came within 1 kilometer. Beluga whales also changed the type of vocalizations and shifted to higher frequencies, perhaps in an attempt to minimize masking.

Strandings

Whales sometimes come ashore and become stranded. Marine mammals are known to strand, and unfortunately many stranded animals die. One controversial issue is the extent to which there is a relationship between the use of military sonar and the stranding of beaked whales. Beaked whale strandings are relatively rare, with 17 beaked whale strandings reported in the U.S. in 1999 and 5 strandings in 2000. Strandings of more than one beaked whale at the same time are very uncommon. Stranding events involving multiple beaked whales have been reported that coincided closely with military activities using sonar. In 3 well-documented cases, there is enough information available to associate the strandings with sonar use. These events occurred in Greece (1996), the Bahamas (2000), and the Canary Islands (2002).

There are a number of hypotheses that attempt to explain the three stranding incidents. The stranded whales in the Bahamas and Canary Islands had tissue damage caused by excessive internal bleeding. One hypothesis that has been proposed is that tissue damage can occur when resonance from loud sounds causes air- or fluid-filled organs (such as the lungs or swim bladder) to vibrate at very large amplitudes. As the organs vibrate, blood vessels and tissues of the organs might become damaged. Another hypothesis compares the whale’s condition to decompression sickness. The scientists suggested that beaked whales might have changed their diving pattern in response to the sounds and come to the sea surface faster than normal, causing bubbles to form in the tissues. Much more scientific research is needed to understand why there is a relationship between whale strandings and the use of sonar.

Hearing Loss

Loss of hearing in marine animals from exposure to sound may be a temporary or permanent condition. The extent to which hearing loss occurs depends on a number of variables including the frequency and level of the sound, duration of exposure, and the health of the animal. The amount of data on hearing loss in marine animals is limited. The majority of data on marine mammal hearing has come from studies of the anatomy of the ear of different marine mammal species.

Hearing loss depends on the intensity and frequency of the sound, and how long the animal is exposed to the sound. Humans exposed to extremely loud sounds for short periods of time (e.g. rock concerts, explosions) may experience temporary or permanent hearing impairment. Similarly, human hearing damage can also be caused by exposure to moderate levels of noise over long periods of time, as in a noisy work environment. Animals can suffer hearing loss for the same reasons.

Overfishing The celebrities of the ocean – tuna, salmon, whales and seabirds - are in danger of losing their food supplies as a result of heavy fishing. Overfishing, as it is often called, basically means catching too many fish; fishing so much that the fish cannot sustain their population. The fish get fewer and fewer, until there are

none to catch.

Several of the world’s largest commercial fisheries include small fish such as herring, pollock, and mackerel, which support the vast ocean web of big fish, marine mammals, and seabirds (See Figure 1). The loss of these small fish at the bottom of the food chain can pose serious danger to other species. Some of these dangers include malnutrition, death of offspring or disruption in migration and breeding patterns.

Fish are an important component of the ocean’s web life and do all the work in the ocean. Often times, people forget how important fish are as wildlife in interdependent ecosystems. In the past, it always seemed that there was an unending supply of fish. Now, we know that is simply not true.

Today, many marine ecologists think that the biggest single threat to the ocean’s ecosystem is overfishing. The world’s appetite for fish is far exceeding the ocean’s ecological limits, and this appetite could possibly have massive impacts on marine ecosystems. Scientists warn that overfishing results in profound changes in our oceans, perhaps changing them forever.

Figure 1: Smaller prey fish are in high demand.

Overfishing has severely depleted cod stocks in the Atlantic. The cod catch has plummeted over the past 30 years and some fisheries have been closed entirely. FAO warns that cod and many other heavily fished stocks will recover only if catches are sharply reduced and

carefully monitored for at least a decade.

Data source: FAO Fishstat 2004

A variety of factors have influenced the increased demand for fish including the increase in populations of the United States and the world, increase in fish consumption by many people trying to live healthier, and improvements in fishing technology which makes fishermen more efficient at their jobs. The reality of fishing in the 20th century is that the industry is dominated by fishing boats that far out match a fish population’s ability to replenish itself. These boats can have state of the art technology to help locate fish quickly and accurately, hold tons of fish, and stay out longer at sea.

A purse seiner net is used to haul tuna to coastal feeding pens

Photograph by Paul Sutherland via National Geographic

1 EPA Polluted Runoff http://www.epa.gov/owow/NPS/nps_edu/urban.html 2 Bureau of Ocean Energy Management, Regulation and Enforcement, http://www.gomr.boemre.gov/homepg/regulate/environ/rigs-to-reefs/artificial-reefs.html 3 Discovery of Sound in the Sea, http://www.dosits.org/animals/effectsofsound/marinemammals/