How have pigeons in eastern North America evolved?

Methods

Summary

one bow net trap will be set and baited .This trap will be set where birds naturally congregate. After several birds are within trapping range, the trap will be deployed,  and any captured birds will be removed. The trap will not be deployed if any birds other than rock doves are within trapping range.  All other species captured will be promptly released. Once brought to the study site (very close to capture site), the target species will have measurements taken of them. The measurements for rock doves are as follow:

Bill length, from outer tip of upper mandible to nare.( mm)

tail length (mm)

Tarsus length (mm)

wing chord (mm)

wing length extended (mm)

Head length, from bill tip to back of head.(mm)

Overall body length, from base of bill to tip of tail.(mm)

Weight ( grams)

Length of leg feathering from start of leg to end of feathering. (mm)

Once  these measurements have been taken, the tip of the first secondary feather on the left wing will be cut in a V-shape. This process will not harm the bird or it’s ability to fly in any way. The shape and location of the clipping is to insure against the re-measurement of the same bird in preceding trials. The bird will then be photographed, then released.This procedure will be repeated until 50 different birds have been captured, measured and photographed. birds that will be expected from the study include those that are injured, sick or of domestic origin. in these cases, they will be brought to either a local wildlife rehabilitation facility or Animal shelter (see non releasable bird protocol).

materials list:

1 Calipers (making mm Measurements)

1 Gram scale  (mass measurements)

1 Small container (for weighing birds)

1 Bow-net trap ( for capture)

1 Millet seed/ cracked corn (bait)

X Large Cardboard boxes (transport and temporary holding)

1 Pet carrier (transport and long-term holding eg, domestic birds)

1 Flagging( keep public away from traps)

1 Signs (keep public away from traps)

4 food/water dishes ( for long-term holding)

X Towels/rags ( always good to have a few with birds)

1 Scissors ( making feather cuts)

1 Antibiotic cream ( for minor bird injuries if found)

Challenges

permitting and approval from potential capture sites has already been a problem. of course, after a great deal of emailing and paperwork, this challenge has mostly been overcome. as with working with any wild animal, their is always an issue of making sure that the animal is present at the study site. I have used ebird's species map tool to help find areas with high pigeon density, but trapping 50 pigeons may be a challenge. to be completely honest, I am not sure of all of the challenges I may face, this Is my first field study.

Pre Analysis Plan

Null hypothesis:

If the morphological traits of various individuals of different rock dove populations are analyzed, no significant difference will be found in the traits from individuals of each population.

statistical analysis:

standard deviation will be used to identify if a significant difference exists in the different populations of rock doves. then a T-test will be conducted on each variable to again check for significant differences.

data collected :                                                                                                                                 color and pattern, (this will be found after the field portion of this study using photos to minimize handling stress on the birds). Please note that I have used the traditional pigeon-keeper names for these traits so they may be unfamiliar to some.

Color:

Blue

White

Brown

Red

pattern/modifier:

Resesive red

Light check

Dark check (t-check)

Grizzle

Bar

Smoke

Pied

White-winged

Bronzewing

Spread

Barless

Eye:

Orange

Pearl

Bull

Albino

other

Each bird captured will be assigned a number and will have its plumage color(s) marked as well as its eye color and plumage color modifiers.

data collected: morphometrics

Bill length, from outer tip of upper mandible to nare.( mm) 

wing length extened (mm)

Tarsus length (mm)

tail length (mm)

Wing length, from base of wing to longest primary feather(mm)

Head length, from bill tip to back of head.(mm)

Overall body length, from base of bill to tip of tail.(mm)

Weight ( grams)

Length of leg feathering from start of leg to end of feathering. (mm)