Saturday, 21 April 2012

Rarities in Ontario

While procrastinating for my exams the other day I created a graph that shows the number of rarities found in Ontario for every day of the year:

Notice anything surprising?
The general trend was expected. But that peak in May is way over the top. And it doesn't even seem like a coincidence.
Here are the numbers (date in May on the left, and frequency on the right):

11 75
12 64
13 73
14 74
15 64
16 56
17 76
18 56
19 59
20 54
21 54

That's a solid 11 days when 50+ rarities have been discovered over the years on that date. Yet every one (and I mean every single one - see for yourself) of the other days in the year have less than 50! So in terms of statistics, that is a "p-value" of 0.05 or less (or  >.95 depending on how you choose to calculate it)!

Anyway, I thought it was an interesting observation. Of course the data will be a bit skewed towards having higher values in May because that's when many birders come out of hibernation. But I'm pretty sure those people are birding all of May, not just May 11-21? And I have a feeling that they aren't the rarity finders... but I could be wrong?

*Credit goes to the guys at Long Point for compiling all the data in that file*
The 4000+ plus records for Ontario puts the ~300 Newfoundland records to shame! I do have another 300+ in the works though (that's a summer project).

Anyway, I've got 3 megas (aka exams) this week... so I should be working on those.

Don't forget about the Bird Song Quiz below. I don't think anyone has aced it yet!
And thanks to everyone who has been participating. If you're eager to continue learning check out this new site/software - it's pretty impressive.

1 comment:

  1. Hey Alvan,

    This is a really neat visualization of the data. I`m curious where you got the data for it and what the definition you used for a `rare` bird was.

    I think the spike in May is definitely real but it is definitely partly because of `the Pelee effect` - everyone and their mother is out birding in mid May. I bet if you could standardize it for effort October would actually be better or for true rarities...

    Anyways, looks good! When you back in Ontario?