ACTIVITY DESCRIPTION: Students learn how water pollution can affect plants and animals through bioaccumulation. MATERIALS 16 eagle ponchos 60 fish (15 of each colour) Bin for lake 8 hula hoops Fish colour chart 4 Velcro fish pictures Make sure you have all items before the students arrive!
THIS IS NOT A SCRIPT - IT IS A GUIDELINE BEGIN THE ACTIVITY What will I be doing? Help the students put on their eagle ponchos. Ensure the students know that in wearing this eagle poncho, they have now become eagles. Aid in the calculation of points using the fish colour chart. Lead a discussion on how contaminants in water can get into fish species, and ultimately affect animals that eat the fish, and what we can do to protect them. Background Information Prior to European settlement, Bald Eagles were abundant along the north shores of Lake Erie and Lake Ontario. An estimated 200 pairs nested from the Ottawa River to the lower Great Lakes and nesting densities were as high as one nest per mile of shoreline along Lake Erie. Loss of nesting and foraging habitat along with direct human persecution led to a marked decline in the Bald Eagle population in the southern Great Lakes. The introduction of protective legislation helped the southern Ontario eagle population rebound to approximately 100 pairs by 1950. Unfortunately, this recovery was short-lived due to the introduction of certain pesticides, such as DDT and PCBs, into the Great Lakes aquatic food chain. From the 1940s to the 1960s, tonnes of chemical compounds were deposited into the Great Lakes, either by direct application or through transportation by air or water. These chemicals settled into the sediment of lake bottoms. From there, they spread to the tiny aquatic plants and organisms and then into the bodies of fish and fish-eating birds. This effect has 2 processes, bioaccumulation and biomagnification. Bioaccumulation refers to the increase in concentration of a pollutant from the environment to the first organism in a food chain. This means that one animal gets contaminated by eating another animal that is already contaminated. Biomagnification refers to the increase in concentration of a pollutant from one link in a food chain to another. This means that as animals eat a greater number of creatures with contaminants, they become even more contaminated themselves. This accumulation of chemicals in the eagles bodies caused severe eggshell thinning. Eggshells were so thin that the incubating birds often crushed the eggs in the nest. For those eggs that did hatch, the young often had life threatening deformities. Canada and the United States have since restricted the use of DDT and tightened
regulations for disposing of industrial chemicals. The populations of Bald Eagles are slowly rebounding. There are a few nests located throughout Elgin County. Other Eagle Facts: Eagles have more than 7000 lightweight and extremely strong and flexible feathers covering their body assisting in regulating their core temperature and maneuvering around prey. In southern Ontario, Bald Eagles favour nesting territories near large water bodies and nest in a variety of tree species. Eagles feed primarily on fish, mammals, and aquatic birds, but will scavenge dead prey when necessary. Bald Eagles will attempt to obtain food by whatever means possible, including stealing from other birds or even scavenging fish killed through hydro turbines or road kill. Activity Set-up Place bucket/tub/bin in centre with all fish to be used, this will be the lake. Place hula hoops ( nests ) approximately 5 metres away circling the lake (about 5 large strides) and at least 2 metres apart (about 2 large strides). An example of the suggested layout is shown in the picture below.
Activity Overview The goal of this game is for the students to gain the highest number of points by collecting healthy fish, rather than contaminated ones. Divide the group into pairs and help the students put on their eagle ponchos. Going around the circle, assign each Eagle pair a mealtime (i.e. breakfast, lunch, dinner). Instruct them that when their mealtime is called, one of the pair will fly to the lake to retrieve a fish to feed the nest (this should avoid the stampede effect of everyone running to the fish at once). Set up the fish colour chart by placing the Velcro fish pictures on the board so that one colour represents the healthy fish and three colours represents the fish that have been contaminated by oil, road salt, and dog poop. The students should not know which colours are which, so make sure that the chart is not visible. Place 15 of the good coloured fish in the pool and place only 10 of the remaining three colours. Each pair starts from their nest (hula hoop) and upon hearing their mealtime runs one member of the pair at a time to the lake (pool) to grab a fish without knowing which colour is which. Students must take turns within their pair and can only take one fish at a time. Once the first student has returned to the nest, the second student must wait to hear their mealtime called once again before taking their turn to retrieve a fish. This is done for a total of two turns each (allowing each pair to gather 4 fish in their nest). After each student has taken two turns, reveal the fish colour chart. Have the pairs gather their fish and calculate the number of points they have collected using the fish colour chart. A total of 7 or more points are needed for the eagle families to survive. Remember to change up the colours of the fish on the board before playing the game again. What made this game tricky? Wait for answers. Not knowing what colours of fish were safe makes it hard to pick the right ones. Eagles cannot tell if a fish has been contaminated by chemicals and other pollution. This makes it difficult for them to survive because they aren t able to pick only the healthy fish.
What can we do? Can anyone tell me what we can do to stop contamination of the water to help protect eagles and other animals? 1. Don t use pesticides on lawns 2. Use sand on walkways and driveways instead of salt. 3. Never pour oil and other hazardous waste down the drain. 4. Pick up after your pets. WHAT HAVE WE LEARNED? Keep our water clean! Animals and plants need clean water to live! Updated April 28, 2016