You’ve heard a lot from me. Here are two very nice perspectives on the why and how of green big days: the first by Andy Kleinhesselink, the second by Josiah Clark.
Why do a self-propelled/Green/carbon-free/bicycling Big Day?
It doesn’t matter what you call it, doing a Big Day without a car is something very few birders have done. Why add the extra twist to the already crazy sport of the Big Day?
It’s not really about being “green”
The conventional Big Day records take a lot of driving—the ABA Big Day record (an astonishing 294 species!) required driving over 300 miles across the state of Texas. This year the record holders, Team Sapsucker, plan to go even farther, from Arizona to the California coast. That’s an amazing feat of birding but also a lot of driving—especially when you consider all the scouting that goes into such a long route. Driving for birds contributes to the elevated carbon dioxide concentrations that are acidifying the oceans and warming the climate—ultimately these effects may be endangering many species of birds that we hope to see.
But even a 300 or 500 mile Big Day drive is really nothing compared to the thousands of long trips birders make each year to chase rarities. And it’s even less when you compare it to the estimated nearly 3 trillion miles Americans drive each year.
Any way you add it up, birding just doesn’t add much to global warming. Doing a green Big Day is a beautiful gesture towards less carbon intensive recreation, but it’s not really a pragmatic environmental solution.
It’s more efficient
The truth is that what makes a self-propelled Big Day (lets face it a Biking Big Day) so compelling is that it is more of an adventure than any driving Big Day could ever be! During a Big Day by bike you can hear and see birds all around you the entire day — even while you are moving! In a car you can only hear birds well when you get out of the car. And you can only see a fraction of the birds that are around you from the inside of a car. You want to be one with the birds? Then get on a bike. Not only does a bike let you detect birds non-stop, it also lets you get to some birds that you can’t even get to in car. Any birder knows the stress and danger of pulling over to look for birds on the side of a busy road. On a bike that danger is greatly minimized because there are just many more safe and legal places to stop a bike than there are to stop a car. Not only that but in many places the best birding can be done along designated bike paths and trails. During a Big Day, these spots often take too long to walk to from a parked car but you can get to them easily on a bike. On our Santa Clara Big Day last year we took advantage of the many miles of the Bay Trail that goes along the south end of SF Bay. Hitting all these spots would actually take longer and yield fewer birds in a car. In fact our species total last year, 181, is nearly as good as the Santa Clara Big Day record set by car of 187.
April is the glory month for diversity in birds, where lingering wintering birds are still present and neotropical songbird migrants are just arriving. They are highly detectable as they sing and set up breeding territories. While a heat wave is not the best for a long distance bicycling event, it is among the best conditions for a spring “migrant fallout”. We find the best conditions for bird watching are often the most difficult conditions for the birds themselves. The high-pressure stops North bound migrants in their tracks, which otherwise stream into the prevailing wind. At dawn these nocturnal migrants set down in mass on ridges, like Skyline in the illuminating light, where they regroup into feeding flocks and reorient themselves. Windy NW conditions are generally the worst for birding, as it shuts down activity and makes hearing birdsong difficult.
Somewhat counter intuitively, flying into the prevailing north wind creates lift (Bernoulli’s Principle) and keeps songbird migrants (the bulk of the species) on the move and virtually undetectable. (Conversely large movements of seabirds (few species), notably loons and shorebirds can be seen flying north over the ocean on north wind days. ) The heat also forces migrating songbird athletes to search for food and water, usually around riparian areas, making them easier to find. At the same time raptors, which use thermals can be seen throughout the day slowly working their way north. Shorebirds are also forced to stop and can be seen in mass along the bayshore. 90% of the northbound shorebirds on the Pacific Flyway pass through SF Bay within one week of April 15, basically now.
The team “The BeastMasters” consists of myself and PHD students Rob Furrow and Andy Kleinhesselink