Idea taken from Josh and Brandon... Thought it might be interesting!
I've kept a list for a while of all the birds I haven't seen in Ontario that fall into 2 categories: more than 10 records for the province or less than 10 but mostly in the past few years (and therefore more likely to show up in the near future).
To see 400 species in Ontario takes a fair amount of effort (twitching) but I suppose if you were really dedicated you might be able to find 400 species in the province. At the end of 2013, the Ontario list sits somewhere between 490-493 depending on whether some records are accepted or not. Since I was only in the southern Ontario twitching scene for a few years, my Ontario list is a bit lower than some of the other 'young' birders with some pretty gaping holes in it. Here I will outline those holes and see how close I could get to 400 for the province - won't be happening any time soon but maybe I will eventually get there! The species that say 'on my Michigan list' were almost all at Whitefish Point - a mere 15km or so from the Ontario border.
Current list: 345 species - meaning I need 55 more to hit the magic mark.
The easy ones: species that aren't even on the Ontario review list because they show up so often...
Common Eider - review species in south but not north
American Avocet - on my Michigan list...
Ruff - getting rarer???
Northern Hawk-Owl - these things breed near SSM but are my Canada nemesis bird...on my Michigan list...
Black-billed Magpie - need to drive through Rainy River
Lark Sparrow - dipped on about 4 of these buggers just this spring...on my Michigan list...
Smith's Longspur - breed up in Hudson Bay
running total: 353
The 'easy' ones - lots of ON records but require some effort to find (or twitch) - numbers are approximate as I only have the records up to the end of 2011, so may have been more since then!
Little Blue Heron ~ 70 records
Tricolored Heron ~ 35 records
Mississippi Kite ~ 40 records
Swainson's Hawk ~ 60 records - on my Michigan list...
White-winged Dove ~ 40 records - on my Michigan list...
Scissor-tailed Flycatcher ~60 records
Northern Wheatear ~35 records
Blue Grosbeak ~90 records - on my Michigan list...
running total: 361
The tough but doable ones - either more than 10 ON records or species that I think will be more frequent in the coming years.
Northern Fulmar - this'll be the time I get up to Netitishi
Black-capped Petrel - need a late August/September hurricane for this and several other species
Neotropic Cormorant - probably going to be more of these in the next few years!
Ross's Gull - already missed 2 of these babies - still trying to find one in the Sault...
running total: 388
That leaves me with 12 CMF birds to either find or twitch. What do I think/hope those might be???
Hurricane birds - maybe a shearwater or something crazy like a Trindade petrel - even a tern would be good
Magnificent Frigatebird - missed that Rondeau bird but I'm sure there will be more
Black Rail - may have found one in 2012...
a rare shorebird - Snowy Plover? European vagrant of some sort?
one of the alcids - Thick-billed Murre? Ancient Murrelet? Tufted Puffin? who knows
Groove-billed Ani - hasn't been one in 25 years so we are due, right?
Common Ground-Dove - on my Michigan list...
tropical swift sp. - just because
hummingbirds - not sure why Ontario is so hummingbird-poor but if I get a house here I will be putting up feeders in the hopes of attracting some! Anna's and Allen's are probably the most likely.
western flycatcher sp. - Dusky, Gray, Hammond's, Western Wood-Pewee, 'Western' - one of them will show up eventually
Vermilion Flycatcher - on my Michigan list...
Gray Kingbird - may have found one in 2011 - better views or photographs required!
Violet-green Swallow - just a matter of picking it out from the thousands of Trees
western warbler sp. - Virginia's, Hermit, Lucy's, Red-faced, Golden-cheeked, etc...
Green-tailed Towhee - on my Michigan list...
Black-throated Sparrow - only 3 records but I think it'll turn up again
Great-tailed Grackle - I am guessing there will be more of these in Rainy River in the next 10 years or so
Bullock's Oriole - how have we not had more records of this???
Eurasian Tree Sparrow - a number of records from Whitefish Point, just need one to end up in the Sault...
That would leave me at well over 400 - of course this relies on me actually being in Ontario to look for these things, and Southern Ontario at that - the Sault isn't exactly a great location for twitching...