GEOG 442
Biogeography
Urban Biogeography Self-Guided Field Trip
Urban Fauna: Field Observation
Each student will do a "pigeon watch," following the procedure of the PigeonWatch project, Cornell University, Department of Ornithology. This project illustrates the use of citizen science to generate data in support of a scientific investigation. Citizen volunteers (or, ahem, students "volunteered" by their professor) collect simple data for processing by others elsewhere. Other examples of citizen sicence projects are Tokyo University's International Pellet Watch program to monitor persistent organic pollutants in "nerdles" washed up on beaches, the California State Water Resources Board Citizen Monitoring Program, and the SETI screensaver program. Since this is a biogeography course and since your professor is notoriously fond of pigeons, in this case Columba livia, this lab will follow the Pigeon Watch protocol.
Getting Your Data
Doing a Pigeon Watch entails visiting a site frequented by pigeons somewhere in the region, whether urban commercial, industrial, suburban, or coastal, long enough to census the number of birds present, count color morphs among them (using the seven morphs described on the Pigeon Watch poster on my office bulletin board or by visiting the PigeonWatch Fancy Threads page), and noting which color bird engages in courting behavior towards which other color bird(s), marking each separate target of a courting male.To do this lab, print a copy of the Pigeonwatch Habitat Form and the PigeonWatch Tally Sheet.
Read the Pigeonwatch instructions to become familiar with the goals of the project and the procedures involved.
Then, select four different spots to observe pigeons according to the instructions. Count on spending at least fifteen minutes at each spot. You are looking for some place where pigeons are hanging out. They are often found where they might find food, such as fast food restaurants, parks where people feed pigeons, urban areas where people drop food, or beach areas. I would like to see observations made in a variety of locations: perhaps an urban-industrial area, a commercial area (shopping center or strip), a suburban residential area (single family dwellings or apartments), and a coastal location (hey, a day at the beach, with credit!).
You might want to coördinate with one or more people in class to get these locations covered. It would be okay for two people to share pigeon watching duties, but, if you collaborate, please do at least six (instead of four).
Writing up Your Results
Fill out the field data entry form during your visit and bring them to class on the day after the Thanksgiving break, together with any field notes for questions or clarifications or reactions you may have. Please be very careful to describe where, exactly, you set up each Pigeon Watch. Be sure to print a map of each area, marking it with your site(s). You can use Thomas Bros. map pages or online map providers, such as Google Maps, Yahoo Maps, MapBlast, or Mapquest.Additionally, please write a paragraph or two verbally summarizing the proportion of each flock in each of the seven color morphs, the number of courtship attempts you recorded, and the distribution of color morphs among the pairs of pigeons involved in a courtship sequence. Which morphs were most common? What colors were the hopeful males and, for each color of male, what was the distribution of color morphs he went after? Do you see any patterns? Were there differences between your pigeon watch sites in these numbers and proportions and what was the character of each site you visited? You might want to read the Pigeon Watch "Why Study Pigeons" essay at to look for a context to put your observations in.
Make sure to autograph your forms and your essay!
I'll assemble the data and send them on to Cornell after the semester ends, where they'll add to an international citizen science project attempting to document the coloring of feral pigeons all over the world and the mating preferences of males and the selections by agreeable females. The purpose of this data collection is to learn how much morphic diversity is being maintained in feral flocks and whether that diversity is being maintained by sexual selection. The proportions of any allele in any population is a balance among natural selection (including sexual selection) and introduction of genes through mutation or migration.
My sneaking suspicion after watching pigeons for several decades is that sexual selection may have little to do with the maintenance of morphic diversity against natural selection pressure for cryptic coloration: The various morphs are constantly being re-introduced by coop escapees. Humans have selected for white, pied, grizzled, black, red, and any number of other odd colors and patterns. Indeed, many domestic breeds are defined by particular coloring or bizarre feather patterns, among other traits. And every pigeon breeder regularly loses birds. Those that are at least minimally fit flyers have at least a small chance at survival in the "wild," and these survivors bring their odd colors with them. So, the Cornell lab focusses on sexual selection, while I suspect migration from domestic flocks maintains the small numbers of strange colors out there. Enough citizen science data may be able to differentiate the two hypotheses!