Date: 9/15/20 11:02 pm From: Alvaro Jaramillo <chucao...> Subject: RE: [MBBIRDS] Smoke birding question for the experts
The exact way in which different species orient during migration is somewhat of an unknown. Do all species do it the same way, or not? What is known is that birds use multiple different independent systems, from stars, to magnetic polarity, land features, polarity of light etc. They also can recalibrate systems, based on the angles of light at sunset, and they do not have to recalibrate daily, but every “once in a while.” As such, they seem to have a pretty robust system for navigation. I don’t think one need worry about the birds not migrating or getting lost strictly due to the fires and smoke. Although they may show more errors, and perhaps less efficient migration due to these errors.
What is the bigger unknown and perhaps a key issue that may not be well studied is what the effect of the bad air has on their physiology. Birds are high metabolism critters, and when migrating they are puffing through a rather immense amount of air for their body size. They have a super efficient system that has no “dead air” when they breathe, unlike our lungs. So there is air passing through their lungs at all times, lots of it, more per unit mass that passes through our lungs. If there are issues where the birds cannot breathe properly, or their high energy flight requirements are not allowing for enough oxygen to get through, that could be a problem. I assume that this is not well studied, and is a big unknown, but I may be wrong.