With all the presentations complete, ALL groups claimed that both abiotic and biotic factors affected the trout population from the 1930s-2000s.  Students used quantitative and qualitative evidence to back up their claims.  Check out each of the group's presentations!  Way to go 6th grade!  I will certainly miss you next year!

And last but not least, we've got a movie!

And while the presentations roll in, we did another technology challenge to summarize our learning!  We made some word clouds that accentuate key scientific vocabulary from our life science unit!

As we wait for our presentations to be finished regarding what affected the trout population, sixth graders were challenged to make a meme on one of the following themes as they relate to our Life Science Unit.  Students were to make a meme on one of the following:

​Table 1: Predator/prey relationship
Table 2: Competition
Table 3: Stable populations
Table 4: Food Webs
Table 5: Structure/function 
Table 6: Abiotic factors
Table 7: Bioaccumulation

Something's a little fishy here...

We are pretty much in agreement that the sea lamprey's invasion into the Great Lakes explains the decline in the trout population starting in 1945, but what we aren't so sure about what the rapid decline of the sea lamprey in 1960.  What's causing this decline?  Is it a biotic factor like food supply?  Or can it be abiotic, like pollution?

We learned a bit about a chemical called dioxin and its effects on a food we through bioaccumulation.  Here is some data Mrs. Brinza got her hands on...

We started to put two and two together that the dioxin had an impact fairly deep.  Our understanding of bioaccumulation would also help explain why the sea lamprey, who as an invasive without any predators, would end up with the most dioxin in its body, and therefore, see the greatest dip in its population.

​As this student's meme points out...

All this makes us wonder though...what happened to keep the sea lamprey population so low and the trout population rebound in the 1980s?  Was this when lampricide was introduced and a limit to the production of dioxin as a waste product? 

​Check out this website which gives great information on the usage of lampricides!

Using the computer model to simulate an invasive and the effects that its arrival has on a stable ecosystem, students determined what an invader ate.  They used the graphs and the data to see how populations of organisms fluctuated over time and how competition between organisms affected population size, too!

Students then took to Google Drawing to make their evidence that much clearer to the reader.  Check out the three examples of the evidence they collected above.  Way to go sixth grade!

Everyone in the sixth grade claimed that the invasive sea lamprey had an impact on the trout's population.  Its advantageous structures (mouth, teeth, gills, swimming ability and total number of eggs) prove it to be a predator, but some of the data we found doesn't match up with that claim.

By 1980, the trout population was on the rise, and we would expect that the invasive sea lamprey's population would follow en suite.  But it didn't...and we see a steady decline to where it almost disappears by the time 2000 rolls around.  What other factors can be causing the trout's population to rebound while the lamprey's population to decline?

We did some research to learn of human impact to reduce the sea lamprey's success, like with the development of some barriers and chemicals to aid in a reduced population.  But is is possible that another organism can be competing with the lamprey for either its food, or maybe another resource it needs, like water or space?

Our best bets at figuring this out are to use a computer model that shows population changes between three organisms.  As these organisms compete for food and space, what happens?  We'll be using a computer based model to help explain this!

After a careful examination of the trout and lamprey's structures that could give them an advantage or disadvantage, sixth graders are using all the evidence they've gained to support a claim to the question:  Could the Sea Lamprey have a major impact on the trout population?  

They also spent time building physical models this week...it really gave insight into how each of the organisms' structures aided in its success or failure!  

We're still wondering if we have the whole picture to this trout mystery though, as there are points in the graph that don't match up with the whole predator/prey claim.  Hmmmmmmmm....