User: | Open Learning Faculty Member:
The biological attribute I am going to study is the number of birds in the yard. I am defining “in the yard” as: landing in the trees, bushes, on the fence, on the shed, or in the grass; not including birds that fly over without stopping.
The Environmental gradient I am using is the amount of precipitation: rain/no rain/length of rain. I have decided to use precipitation as a predictor of the number of birds because the termperature in Swift Current is fairly constant while during this season the rain is variable and will provide more variance throughout the test.
I have learned in biology classes that most small birds will wait out rain in some sort of shelter. Rain poses a risk of hypothermia. But smaller birds have smaller energy reserves and therefore can withstand less cold (and less rain) than larger birds can. But one problem of having a small energy reserve is that they can’t go too long without eating and therefore if it rains for a long period of time, the smaller birds will come out of their hiding places for some food. Therefore I predict that if I count birds in my yard immediately after it starts raining, that there will be very few to no small ones, but if it continues to rain then the numbers will eventually start to rise again. I will therefore need to establish the average number of birds that frequent the yard when it is not raining in order to compare the numbers in the variable conditions.
My response variable is number of birds in the yard. The predictor variable is if it is raining or not and how long it has been raining for and how much rain (heavy vs. light).
Hey there!
You may not want to collect information on how long it has been raining for as a response variable. I suggest this for a few reasons:
1) Collecting that data could require a lot of time. Further, whether birds venture out or not, as you’ve mention, is a function of how hungry they are. A bird may venture out after only 2 hours of rain if on the day before they went a great number of hours without eating due to rain.
2) In the prairies where precipitation levels are generally lower than in forested areas, it may not be a variable that has an impact.
Perhaps the environmental gradient could be sunny weather, cloudy weather, and rainy weather?
Hope it goes well!
Cheers,
Rob
PS: When you get to module 4 you will have to offer constructive criticism to another student on their hypothesis as part of an assignment. Check!
This is a really interesting study and I look forward to hearing your results! I am wondering how you are going to categorize precipitation. You mentioned heavy rain vs light rain but how will you judge this?
Also, since your point location is the entire backyard, ie. on the fence, on the lawn, in the trees, how will you ensure that you aren’t double counting birds?
Good luck with your study. I am also studying birds but using temperature as my predictor variable.
Yana