This picture shows interconnections within the marine ecosystem. Declining fish populations can affect everything from kelp to whales.

Sea Otters. Since 1990, it is estimated that hungry orcas have eaten over 40, 000 sea otters. In some areas of the Aleutian Islands sea otter populations have dropped up to 90%

Rippling effects. Will the disapearance of kelp forest creatures affect other organisms, like eagles or sea birds? The effects are not yet known.

Kelp Forests. Grazed heavily by the urchins, kelp forests and the ecosystem they support, are disapearing.

 

 

 

Fish. Some scientists believe that a series of ecosystem changes in the North Pacific (Bering Sea) began with a decline in abundance and distribution of fish. This decline is due to climatic change and increased fishing pressure

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Sea lions & Seals. Decline in fish populations may have led to a decline in seals and sea lions in the Bering Sea.

Sea Urchins. Without their main predator (sea otters) to keep them in check, urchin populations have increased fast. Urchins have eaten back the kelp forests all along the coast.

Orcas. When their favorite food source (seals and sea lions) declined orcas began searching for other things to eat.

What is an MPA?

A Marine Protected Area (MPA) is an area of the ocean that is protected by law in order to preserve areas of high biological importance. It is similar to a park, but the goal of a MPA is to conserve the life and habitat within. This can include the sea floor and all the life above it in the water.

Human activities that destroy habitat or endanger a species by removing too many individuals are banned in a MPA. Marine biologists have identified mining, oil exploration, aquaculture, dredging, and bottom trawling as some activities that may be destructive and need to be stopped in areas that are to be protected. Like parks, different MPA’s may have different goals, in some, fishing and collecting may be allowed whereas others may be no-go zones for anyone.

Marine Protected Areas may become an important tool for creating sustainable fisheries. Past fishery management has simply tried to limit the amount of fish caught, it hasn’t considered entire ecosystems. A MPA can be designed to protect important habitats like spawning grounds, as well unique habitats like deep-sea hot vents. MPAs can also function to save endangered species by protecting their habitat. Protected areas are beneficial for conservation, but are also good for enhancing fisheries and increasing local economic opportunities.

When properly managed and enforced, Marine Protected Areas have been effective in protecting and rebuilding many marine species. The numbers of certain fish and other species often increase in the waters next to a protected area as well. This is a good thing for local fisheries. We call this the “Spillover Effect” because there are no fences in the ocean. If an area is protected from fishing, the fish in that area will be able to grow older and bigger. Larger fish are able to produce more eggs and therefore more juvenile fish. When these juveniles grow up, and the MPA becomes too full, the fish will move out of the area and into fishing grounds where they can be caught by fishers. A couple years after MPA’s were established in Spain, fisheries reported 50-80% higher catches next to these protected areas. MPA’s seem to be doing the job scientists thought they would.

The idea of restricting human activity in parts of the marine environment has existed for centuries. In Fiji, in the South Pacific, fisheries managers are returning to a practice called “tabu ni qoliqoli”. This is a traditional practice of reserving a fishing ground so that fish populations may increase before a special ceremony. The lagoons are patrolled by local villagers and kept off limits to fishing and diving. It works! Elders are again noticing an improvement in the numbers of fish in the lagoons.

Recently, a MPA was established in British Columbia off the south coast of Vancouver Island. The site, called Race Rocks, is a series of rocky islets. Strong tidal currents (up to 7 knots) around the islets provide a generous supply of nutrients for many marine organisms. The area supports an abundant variety of marine life including Northern and California Sea Lions; Harbour and Elephant Seals, River Otters, Dall’s and Harbour Porpoises, Orcas, Gray Whales, Octopi, sponges, corals, anemones, giant barnacles, algae and sea grasses. The students and staff of Lester B. Pearson College put the energy into monitoring and establishing this first MPA on the Pacific Coast of Canada.

Today, less than 1% of the world’s oceans are included in Marine Protected Areas. This means there are not that many places to look at to see whether MPAs are actually working. However, we do know that something needs to be done to reduce the impact that we have on our fishery resources, and MPA’s are a strategy that is likely to make a difference. It is always important to remember that a few protected areas are not a substitute for good fisheries management and that areas that are not protected must be remembered, managed carefully, and not over exploited.

Big Questions?!?

The placement of MPA’s could be difficult, where do you put them? Do you put them in areas that already have lots of fish or areas that have been fished heavily? How big should reserves be? What shape? Should you make one large reserve or many small ones? Will organisms in the MPA be able to persist despite increased pollution or climate change? And how long does it take before fish move out of the reserve to the areas where they are caught by fisherman? Is the area a source or a sink for jveniles? These are all questions that need to be solved by scientists in the future… maybe you?

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