PS 78-197
How long do birds in the southernmost forests of the world live? Maximun longevity estimates

Thursday, August 13, 2015
Exhibit Hall, Baltimore Convention Center
Jaime E. Jiménez, Sub-Antarctic Biocultural Conservation Program, IEB-UMAG-UNT, Chile
Amy L. Wynia, Department of Biological Sciences, Sub-Antarctic Biocultural Conservation Program, University of North Texas, Denton, TX
Rajan Rijal, Sub-Antarctic Biocultural Conservation Program, University of North Texas, Denton, TX
Ricardo Rozzi, Omora Ethnobotanical Park, Universidad de Magallanes, Puerto Williams, Chile
Background/Question/Methods

The ecology of southern forest birds is little known, and even less is known on their longevity.

Here, based on monthly mist netting data of more than 12 years we report on the maximum

longevity of forest passerine birds and we model the relationship of longevity with body mass,

month of the first capture, and migratory status. Between March 2000 to August 2013, in a

mixture of deciduous and evergreen forests at the Omora Ethnobotanical Park (56oS), on

Navarino Island, southern Chile, we caught 1,026 individuals at least twice from the 10 most

abundant bird species. We estimated longevity based on the time period between the first and last

capture of each individual in the mist nets. To evaluate the effects of variables on longevity we

ran a generalized linear model.

Results/Conclusions

Our results show that the longest lived species were the migrant

tyrannid White-crested Elaenia (Elaenia albiceps, 15g, 8.15 years), the resident emberizid

Patagonian Sierra-finch (Phrygilus patagonicus, 23g, 7.60 years), and the resident furnarid

Thorn-tailed Rayadito (Aphrastura spinicauda, 12g, 6.85). However, mean longevity for these

species was 1.27 (n=123), 0.89 (n=318), and 0.80 (n=427) years, respectively. The results of the

generalized linear model indicate that the date of first capture, the body mass, and the month

when a bird was captured were the factors that best explained the longevity of the

birds. Although the three migratory species were twice as small (14.08g) as the 6 resident species

(28.97g), there was no effect of body mass on longevity. The estimated longevities are

conservative values of how long each bird species can live as most of these birds were banded as

adults and they still lived after their last recapture.