VDGIF/Norfolk Botanical Garden Eagle Cam: Banding results

The Virginia Department of Game and Inland Fisheries, in partnership with the Norfolk Botanical Garden and WVEC, is providing a rare glimpse into the life of two bald eagles and their offspring!

Thursday, April 23, 2009

“Banding results”

Yesterday's banding of the three eaglets at the Norfolk Botanical Garden was successful. Climbers from Nuckols Tree Care (who volunteered their services) accessed the nest and lowered the eaglets to biologists from the Center for Conservation Biology at William & Mary. The weather gave us brief cause for concern as a small rain squall moved through the area - but close monitoring of radar maps indicated that we could proceed safely.

All three of the young eagles looked healthy with no signs of any problems. They were weighed and measured, with a small blood sample taken in an effort to develop a DNA database of bald eagles. The measurements allow biologists to assess the development of the chicks and can be used to identify the gender of the chicks. The information is summarized below - note that the sex of one of the eaglets could not be determined as its measurements fell in between the range for male and female birds.

Eaglet #1 - Band # 679-01346 Color Band: HK
Hatched March 21st
Gender: Male
Weight: 2630 grams (5.80 pounds)
Wing Chord (length of wing from wrist to end of longest primary feather): 23.9 cm
Tail Length: 7.8cm

Eaglet #2 - Band # 679-01345 Color Band HH
Hatched March 22nd
Gender: Unknown
Weight: 2973 grams (6.55 pounds)
Wing Chord: 22.5cm
Tail Length: 4.5cm

Eaglet #3 - Band # 679-01344 Color Band HE
Hatched March 25th
Gender Male
Weight: 2715 grams (5.99 pounds)
Wing Chord: 20.2
Tail Length: 4.5cm

Note that although the oldest bird has the lowest weight - its feathering was notably more advanced then its siblings

Each of the chicks were fitted with two bands. These bands are issued by the US Geological Survey Biological Resources Division, who manages the Bird Banding Laboratory (BBL) at the Patuxent Wildlife Research Center in Maryland. The BBL maintains a database with information on all birds banded under its authority. The first band is aluminum and has a unique alphanumeric code. The code on this band identifies the location and date the bird was banded along with any other vital information recorded. These bands can be difficult to read in the field (although it is possible with very good optics). The second is a color band and has a two letter code and is more easily read in the field. All birds banded in the Chesapeake Bay region are fitted with purple bands. The public can report sightings of banded birds at the BBL website Bird banding provides valuable information to researchers that can be applied to bald eagle conservation. Reports of bands can reveal something about the movements of bald eagles once they fledge from the nest, as well as information about longevity. The bands are more then large enough to accommodate any future growth and small enough to remain securely attached

The researchers that perform this work are highly experienced and able to accomplish this task with minimal disturbance to the birds. The eaglets were banded at this stage in their development because they remain fairly docile during the procedure. The adults soared overhead but did not interfere with the banding. Shortly after the equipment was moved from the base of the nest tree one of the adults returned to the nest. By 2:30 pm the female had returned yet again to feed all three of the eaglets. The eagles have since resumed their typical schedule.

In May, one of the chicks will be fitted with a satellite transmitter. This will provide real time data allowing the movements of the bird to tracked once it leaves the nest. The transmitter is relatively small and does not interfere with the bird's flight. This transmitter will collect invaluable data and help fill in information gaps regarding the movements of eagles. This type of data will inform future management decisions and identify important habitats and resources.

From left to Right: Dr. Bryan Watts (eaglet #2), Reese Lukei (eaglet #1), Stephen Living (eaglet #3)