DATA COLLECTION METHOD
MIGRATION PROTOCOL
(U.S. & Canada)
Beginning about 1 March, EarthTrek observers in the Gulf Coast states should begin watching hummingbird feeders and flowering plants for the earliest spring migrant Ruby-throated Hummingbird. It takes a while for RTHU to disperse throughout their breeding range, so observers north of the Gulf Coast should begin observations at least a week or so ahead of the migration dates indicated on the map above.
In spring report the arrival dates of your first migrant male and female RTHU, determined by plumage. During summer, report your first sighting of a juvenile male RTHU. During autumn, report the last day(s) you observe RTHU, based on the birds’ ages and sexes.
Migration Protocol (US & Canada) Data collection sheet. Print this sheet off and use it to complete your data collection. Later you will log the data from this sheet online.
NOTE 1: Adult male RTHU have red throats, adult females have white throats. However, because recently fledged males also can have white throats, a late spring, summer, or fall white-throated RTHU could be a female OR a young male. (See accompanying photos and refer to Ageing & Sexing RTHU.)
NOTE 2: Other “red-throated hummingbirds” resembling RTHU occur in other parts of North America but these are some other species--NOT Ruby-throated Hummingbirds, Archilochus colubris. (See accompanying photos and refer to Other Hummingbird Species.)
NOTE 3: Rarely, RTHU overwinter in the continental U.S., especially in coastal areas. Locations for any RTHU present in the U.S. between 1 November and 29 February should be reported directly to RESEARCH.
NOTE 4: EarthTrek observers may also wish to submit RTHU spring arrival data to Lanny Chambers at his hummingbird Web site.
Migration Protocol (US & Canada) Data collection sheet. Print this sheet off and use it to complete your data collection. Later you will log the data from this sheet online.
MIGRATION PROTOCOL
(Mexico & Central America)
Beginning about 1 August, EarthTrek observers in northern Mexico should begin watching hummingbird feeders and flowering plants for the earliest fall migrant Ruby-throated Hummingbird. Based on plumage, report when you see your first adult male and the first appearance(s) of any other age/sex classes. It is not known how long it takes RTHU to disperse from their North American breeding grounds into their non-breeding “winter” range in Mexico and Central America, so depending on your location you will need to be diligent through about the middle of December. In spring report the last day(s) you observe RTHU, based on the birds’ ages and sexes. No one knows when the last RTHU leave the Neotropics on their northward journey, but there are no records for RTHU in Central America or Mexico after about 1 May.
Migration Protocol (Mexico & Central America) Data collection sheet. Print this sheet off and use it to complete your data collection. Later you will log the data from this sheet online.
NOTE 1: Adult male RTHU have red throats, adult females have white throats. However, because recently fledged males also can have white throats, a fall migrant white-throated RTHU could be a female OR a young male. By the time spring migration starts in Mexico and Central America, any RTHU with a completely white throat can be sexed as female. (See accompanying photos and refer to Ageing & Sexing RTHU.)
NOTE 2: Other “red-throated hummingbirds” resembling RTHU occur in Mexico and Central America but these are some other species--NOT Ruby-throated Hummingbirds, Archilochus colubris. (See accompanying photos and refer to Other Hummingbird Species.)
NOTE 3: Rarely, RTHU overwinter in the continental U.S., especially in coastal areas. Locations for any RTHU present in the U.S. between 15 October and 15 March should be reported directly to RESEARCH.
NESTING PROTOCOL
(U.S. & Canada ONLY)
It is believed for most locales male Ruby-throated Hummingbirds arrive first in spring migration, after which they establish breeding territories. Females probably arrive a week to so later, choose a male, mate, and construct a nest from spider webs, lichens, and plant down. Males are not known to participate in nest building, incubation, brooding, or nestling care. RTHU do not nest in Mexico or Central America.
For the RTHU nesting protocol you should collect as much information as possible about various aspects of nesting behavior, based on date. This includes such things as when nest construction began and ended, when eggs hatched and nestlings fledged, etc. Of special interest is the rate of nesting failures, whether a nest is re-used, and if a given female appears to double- or triple-brood.
Nesting Protocol (US & Canada only) Data collection sheet. Print this sheet off and use it to complete your data collection. Later you will log the data from this sheet online.
NOTE 1: It is of utmost importance that you DO NOT DISTURB THE HUMMINGBIRD NEST in any way. Loss of a nest due to observation, photography, or data collection is unacceptable.
NOTE 2: Please report only RTHU nests that are/were active; an active nest is one at which you saw a female building, sitting on eggs or nestlings, and/or feeding nestlings. (Do NOT report old nests or abandoned nests at which you saw no activity.)
NOTE 3: Other “red-throated hummingbirds” resembling RTHU nest in other parts of North America but these are some other species--NOT Ruby-throated Hummingbirds, Archilochus colubris. These nests should not be reported via EarthTrek. (See accompanying photos and refer to Other Hummingbird Species.)