Colour wing-tags have been put on Black-tailed Gulls Larus crassirostris at two breeding colonies in 2001 and 2002:

Rishiri Island : Light Blue
Teuri Island: Red

Numbers are printed on the colour tags for individual identification:

For the birds caught in 2001, letter A and three digits were used (A001-A059 for Rishiri Island, A001-A150 for Teuri Island - remember color of the tags were different). All letters and numbers were printed in black.

For the birds caught in 2002, only 2 digits (00-99) were used. Numbers were printed in five different sets of colors: white, lavender (light purple), yellow, green, and dark blue.

Colour flags have been put on the left tarsi of Black-tailed Gulls born at the following breeding colonies since 1998:

Rishiri Island: Red
Teuri Island: Yellow
Esashi (on Hokkaido): Green
Okushiri Island: Blue

A letter was printed on the color flags to show the year of birth of the banded bird:

A: Born in 1998, B: Born in 1999, C: Born in 2000, D: Born in 2001, E: Born in 2002

All color-marked birds (wing-tagged or colour-flagged) have a metal ring on their right tarsi.

Please report sighting of color-marked Black-tailed Gulls to:

The Hokkaido Institute of Environmental Sciences
postal address: 12 chome, Kita-19-Jo-nishi, Hoku-ku
Sapporo City, Japan 060-0819
e-mail: kamome@hokkaido-ies.go.jp
fax: +81-11-747-3254