Hey Steve

For sure you should keep lists, and not only lists but, if you really want
to start adding to knowledge of these little-visited areas, dates, numbers,
locations, sex and age where possible. If you can, take lots of photographs
for documenting stuff.

One of the reasons is that some species are common as fleas in the high
country but very rare at sea level---ptarmigan, rosy-finches and Pine
Grosbeaks are a good example. In other words, they migrate
mountaintop-to-mountaintop, and there's not a whole lot of data on this
because so few birders are in these habitats for much of the time. Others go
through mountain passes on their way from the coast to the interior in the
northward migration---turns out that in years where snows up high are very
deep, rosy-finches 'trapped' at sea level by snow cover up high will do a
daily commute to high up to see if the passes are open, that is, is there
enough showing above the snow to eat (great thanks here to the guy who
answered my query about rosy-finch and bluebird migration in heavy-snow
years whose emails I've lost in a crash---if you're reading, please weigh in
here) and return to sea level if not. So if it's April and you're seeing
rosy-finches or lots of persistent Mountain Bluebirds at sea level, chances
are the snow is too deep for them to subsist at altitudes more usual for
them.

Here's another instance of what your data, should you wish to record it,
could show, using Vancouver BC birding as a case study. On Nature
Vancouver's older checklists up until the late 1980's, Pine Grosbeaks,
Gray-crowned Rosy-finches and Rock and Willow Ptarmigans were listed as
extremely rare. But that was based on nothing but sea-level sightings: we
were too busy chasing Gyrfalcons and Yellow-billed Loons and other winter
birds down at sea level year after year. Then one late October, an English
birder new to Vancouver asked diffidently if ptarmigan were common in
Vancouver. Hell, no! we replied. Where'd ya see it? Up on Mount Seymour (one
of the local North Shore mountains you can drive up to in 30-45 minutes). Of
course, everyone raced up the mountain as soon as possible to twitch this
new sighting. After a hike, yep, there they are, three or four Willow Ptarm.
And we found a few rosy-finches and quite a few Pine Grosbeaks as well (the
checklist at the time had them as rare, so to see a flock of twelve was
great fun).

Well, next year we went back up there a little bit earlier, and year after
that, and so on. Turns out the 'great rarity' of these ptarms, finches, and
grosbeaks was an artefact of coverage---e.g., no coverage, great
rarity---and that these birds were actually as regular up on the local
mountains as church on Sunday, enough that it was possible to establish
relatively firm arrival dates for them in the southbound migration. Not only
that but we also started seeing species not normally associated with local
mountain-top breeding such as Turkey Vulture (turns out that each local
North Shore mountain has at least one pair) and a local birder named J.
Denham found Northern Goshawk in distraction/nest-defence mode on one of the
local mountains, or mountaintop migrants such as Baird's Sandpiper and
California Gull. And I still can't figure out what the heck a flock of 10-15
White-crowned Sparrows was doing at nearly 1400 meters in January in a
frigid deep-snow coniferous forest (other than literally being stalked by my
lifer Northern Pygmy-Owl). Were they a different, more montane race from the
ones wintering at sea-level? Dunno, never got close enough. But why weren't
they spending the winter like any sane White-crown in January, in a
blackberry thicket and going to dedicated feeders at the Reifel Refuge? Is
this just more sea-level-centric thinking? No one knows, but there may be a
pattern of high-altitude wintering we know little about just for this one
species. See the possibilities?

And what about migration of other species? At high altitudes, who shows up
where, and when? In either direction? Who stays and breeds? There's tons of
questions even minimal sighting information can help clarify because there's
still a huge amount we don't know about mountaintop-to-mountaintop
migration, who arrives/winters/breeds/departs where. So, yeah, Steve, I'd
encourage you to keep lists, and whatever other data you're comfortable
collecting. But especially dates, 'cos that's what really gives you the nuts
and bolts of migration, breeding and wintering. If you can add age and sex,
bonus.

best wishes

Michael Price
Vancouver BC Canada
loblollyboy at gmail.com

Every answer deepens the mystery.
- E.O. Wilson
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