A female Bristle-thighed Curlew (Numenius tahitiensis) collected on Laysan Island on 30 Apr. 1991 was at least 23 yr and 10 mo old, making it the oldest known scolopacid in North America. Resightings of Bristle-thighed Curlews marked on Laysan from 1988 to 1990, and recent encounters with two of the 95 curlews banded in 1967, suggest an annual survivorship of >85%.
Division qf Biological Sciences
University of Montana
Missoula, Montana 59812 USA
REGISTRO DE LONGEVIDAD EN NUMENIUS TAHITIENSIS: UNA EXTENSI)N
Sinopsis.--Una hembra de Numenius tahitiensis capturada en la Isla de Laysan el 30 de
abril de 1991, tenla al menos 23 anos y 10 meses de edad, lo que hace de este esp6cimen el
registro mils antiguo conocido entre las especies de escolopficidos en Norte Am6rica. Registros
visuales de N. tahitiensis marcados en Laysan durante 1988 y 1989, y registros recientes de
dos de los 95 ejemplares marcados en 1967, sugieren una supervivencia anual mayor de
85%.
On 31 Aug. 1989, I saw a banded Bristle-thighed Curlew (Numenius
tahitiensis) on Laysan Island, Northwestern Hawaiian Islands, and read
the band number (564-00019) through a spotting scope. The bird had
been banded on 4 Sep. 1967 by Roger Clapp on Lisianski Island, 225
km WNW of Laysan (Marks et al. 1990). At a minimum age of 22 yr
and 2 mo, it was the oldest known scolopacid in North America (see
Miller and McNeil 1988). On 30 Apr. 1991, I collected this curlew on
Laysan Island to assess fat content at the start of spring migration. I
opened the body cavity and determined that the bird was an obese female
(body mass = 773 g, wing chord = 249 mm, tarsus length = 63.7 mm,
exposed culmen length = 92.3 mm). When I collected the bird, > 70% of
the approximately 300 curlews present on Laysan were uniquely color-
banded on their tibiotarsi. I deliberately avoided collecting color-banded
curlews and would not have shot this bird had I known it was banded
(USFWS aluminum band on tarsus). This encounter extends the longevity
record for Bristle-thighed Curlews (and for North American scolopacids)
to 23 yr and 10 mo.
Based on resightings of individually marked birds, the annual survival
rate for Bristle-thighed Curlews wintering on Laysan was 80-90% from
1988 to 1990 (J. S. Marks and R. L. Redmond, unpubl. data). Encounters
with birds banded previously would provide an independent appraisal of
this estimate. In 1967, 95 curlews were banded on Laysan and Lisianski
islands (Clapp and Wirtz 1975, Ely and Clapp 1973). Since 1988, two
of these birds have been encountered on Laysan alone (the collected bird
plus another captured in 1988 and resighted in 1989; see Marks et al.
1990). Given that researchers have spent very little time on Lisianski
Island, and that aluminum bands can be difficult to detect, it is likely
that several other curlews banded in 1967 were alive between 1988 and
1990. This would suggest a mean annual survivorship of 85-90% for
curlews from this 1967 banding cohort.
ACKNOWLEDGMENTS
I thank R. L. Redmond for his continued support in all aspects of the research, and S.
M. Leasure for assistance on Laysan in 1991. The manuscript was improved by the comments
of R. B. Clapp, E. H. Miller and R. L. Redmond. The work was funded by the U.S. Fish
and Wildlife Service (Alaska Fish and Wildlife Research Center, Hawaiian Islands National
Wildlife Refuge, Montana Cooperative Wildlife Research Unit), the National Geographic
Society, the World Wildlife Fund, Sigma Xi, the Hawaii Audubon Society and a Paul A.
Stewart award. The National Marine Fisheries Service, the U.S. Coast Guard and the
NOAA research ship 'Townsend Cromwell' provided invaluable logistical support. Bristle-
thighed Curlews were collected under federal and state permits issued to R. L. Redmond.
LITERATURE CITED
CLAVe, R. B., AND W. O. WIRTZ, II. 1975. The natural history of Lisianski Island,
Northwestern Hawaiian Islands. Atoll Res. Bull. 186.
EL", C. A., AND R. B. CLAPP. 1973. The natural history of Laysan Island, Northwestern
Hawaiian Islands. Atoll Res. Bull. 171.
MARKS, J. S., R. L. REDMOND, P. HENDRICKS, R. B. CLAPP, AND R. E. GILL, JR. 1990.
Notes on longevity and flightlessness in Bristle-thighed Curlews. Auk 107:779-781.
MILLER, E. H., AND R. McNEIL. 1988. Longevity record for the Least Sandpiper: a
revision. J. Field Ornithol. 59:403-404.
Received 15 Jul. 1991; accepted 15 Oct. 1991.