Division of Biological Sciences University of Missouri-Columbia Columbia, MO 65211 U.S. Dept. of Agriculture, Forest Service Institute of Tropical Forestry Southern Forest Experiment Station Call Box 25000, Rio Piedras, Puerto Rico 00928-2500 nowledge of the lifespans of wild birds is of both aesthetic interest and scientific importance. The ac- cumulation of such knowledge can be accomplished almost solely through the bird banding process. Clapp et al. 11982,1983), Klimkiewicz et al. 11983), and Klimkiewicz and Futcher (1987) have recently summarized longevity records for North American birds through a survey of the Bird Banding Laboratory's records. Little information exists about longevity of Neotropical birds, in part because of the limited amount of bird ban- ding that has been done in that region. Here we present estimates of the longevity of Puerto Rican birds gathered during a 15-year study at a single site on that island. Although the number of birds banded cannot compare to the totals for all North American bandings Isee above references I, the longevities recorded are often quite com- parable and provide an interesting first estimate of lifespans for tropical island birds. Additionally, winter site fidelity in some migratory birds provides longevity records comparable to those recorded on the breeding grounds. Study Site and Methods Our banding studies have been done in the Guanica Forest of southwestern Puerto Rico, a 4000 ha reserve that is coverd with the dry scrub forest typical of such climates in the West Indies. Although this area receives nearly 100 cm of rain yearly, little rain falls from December to April. During this period, drying winds, shallow soils, and bright sunlight make for extremely arid conditions which results in a forest that is partially evergreen and includes many arborescent cacti. The short nature of the vegetation (usually less than 20 feet tall) makes mist netting a highly effective technique for sampling the bird population. We have been using a line of mist nets as a population monitoring tool Isee Faaborg et al. 1984), using the tech- nique outlined in Terborgh and Faaborg 119731. All ban- dings reported here were from a single straight line of 16 mist nets 136 mm mesh, 12 m long, Association of Field Ornithologists type ATX) placed as close to end-to-end as possible and run from dawn to dusk for three consecutive days. The number of new individuals captured declines sharply during this period, such that only about 20% of the three-day total is captured on the third day. Samples have been collected during January or early February of every year from 1973 through 1988 except 1977 and 1979, plus samples were taken in June of 1973 and October of 1986. All birds captured were banded, weighed, measured, and released. Recaptures (birds banded in previous years) allow us to estimate avian longevity in this location. We have followed the standard procedure (see Clapp et al. 1982) of listing longevity records as years-months (0-00). The longest recapture period is the length of time between banding and last recapture of a bird. Estimated maximum longevity is the above period plus the time from initial banding to the previous June 1, assuming that all birds were born on that date. Average recapture time is the average time between first and last captures for all in- dividuals of a species caught in two different sampling periods. Results and Discussion We have captured 39 species of birds in this netline over the 15-year period. Of these, 18 have never been recap- tured in subsequent sampling periods (Table 1). Often, this is due to very small sample sizes; in other cases, it sug- gests mobile bird populations, both among winter residents (such as the Cape May and Prairie Warblers) and residents (such as the Black-faced Grassquit I. Recapture information is not available for hummingbirds, as we clip tails to mark them. There is great variation in the longevity characteristics of birds that have been captured in at least two samples ITable 2 I. Some species Isuch as the Common Ground Dove I have large sample sizes but show low recapture rates and short longevity estimates. In other cases, near- ly 30% of banded individuals have been recaptured, often several times, and even average longevity is high. In a few cases, the presence of apparently sedentary individuals has given us a long recapture time despite either small total samples or low recapture rates. Several records are worthy of note. Perhaps the most im- pressive recapture is that of a Puerto Rican Tody which was banded in February, 1974, and recaptured 4 other times, the last in January of 1988. This period of 13 years, 11 months between banding and last capture and an estimated 14 years, 6 month of age is amazing for a 5.5 g bird living in such a harsh environment! Although the estimated ages of 11 years, 7 months for the Puerto Rican Flycatcher and Pearly-eyed Thrasher are impressive, these birds are appreciably larger (22 and 100 g, respectivelyI and seemingly more durable than the body. The age estimate of the flycatcher is exceeded in North America only by the Great Crested Flycatcher IMyiarchus crinitus; 13 years, 11 months [Clapp et al. 198311 among congeners. The longevity of the Pearly-eyed Thrasher exceeds all of these shown for members of the North American Mimidae in Klimkiewicz et al. 11983 I. The maximum longevity estimate for the Puerto Rican Vireo exceeds those listed for nearly all North American vireos IKlimkiewicz et al., 1983 I. Such is also the case for the resident Adelaide's Warbler when compared to North American warblers of the genus Dendroica. Although we have found that the Northern Parula rarely is recaptured, one of our recaptures gives an estimated maximum longevity of 7 years, 7 months, which exceeds that listed in Klimkiewicz et al. (1983) by nearly 3 years. Although only one individual Prothonothary Warbler was ever recaptured, it appeared in the same net over a 4-year span. This longevity estimate of 4 years, 7 month is close to the 4 years, 11 months listed by Klimkiewicz et al. (1983 I. Although one can point out examples like those above it is difficult to make generalizations about the differences between Puerto Rican and North American birds through such comparisons. Yet, given that we are comparing a few dozen to a few hundred birds banded at a single location with often thousands of birds banded throughout North America, one cannot help but get the impression that these resident birds of Puerto Rico are rather long lived, despite the seeming harshness of the seasonally dry forests in which they live. Acknowledgements We would like to thank our wives and many colleagues, students, and friends who have helped with the netting over the years. The Department of Natural Resources of the Commonwealth of Puerto Rico has always been very helpful in granting us permission to do this work. In re- cent years, Miguel Canals, biologist for the Puerto Rican Department of Natural Resources, has provided assistance on a daily basis. Financial support for this work has come from the Frank M. Chapman Fund of the American Museum of Natural History, the Research Council of the Graduate School, University of Missouri-Columbia, the U.S. Agency for International Development, and the U.S. Forest Service, Institute of Tropical Forestry. We also wish to thank James L. Ingold for valuable com- ments on the manuascript. Literature Cited Clapp, R.B., M.K. Klimkiewicz, and J.H. Kennard. 1982. Longevity records of North American birds: Gaviidae through Alcidae. J. Field Ornithol. 53: 81-124. Clapp, R.B., M.K. Klimkiewicz, and A.G. Futcher. 1983. Longevity records of North American birds: Colum- bidae through Paridae. J. Field Ornithol. 543:123-137. Faaborg, J., w.J. Arendt, and M.S. Kaiser. 1984. Rainfall correlates of bird population fluctuations in a Puerto Rican dry forest: A nine year study. Wilson Bull. 96:575-593. Klimkiewicz, M.K., R.B. Clapp, and A.G. Futcher. 1983. Longevity records of North American birds: Remizidae through Parulinae. J. Field Ornithol. 54:287-294. Klimkiewicz, M.K. and A.G. Futcher. 1987. Longevity records of North American birds: Coerebinae through Estrildidae. J. Field Ornithol. 58:318-333. Terborgh, J., and J. Faaborg. 1973. Turnover and ecological release in the avifauna of Mona Island, Puerto Rico. Auk 90:759-779. Table 1. Species and numbers of birds banded in the Guanica Forest which have never been recap- tured in subsequent samples. SPECIES NO, BANDED American Kestrel (Falco sparverius) 1 Zenaida Dove (Zenaida aurita) 3 Key West Quail-dove (Geotrygon chrysia) 12 Puerto Rican Screech-owl (Otus nudipes) 1 Puerto Rican Nightjar (Caprimulgus noctitherus) 1 Antillean Mango (Anthracothorax dominicus) 24 Puerto Rican Emerald (Chlorostilbon maugaeus) 1 Gray Kingbird (Tyrannus dominicensis) 1 Gray-cheeked Thrush* (Catharus minimus) 1 Cape May Warbler* (Dendroica tigrina) 23 Prairie Warbler* (Dendroica discolor) 18 Northern Water-thrush* (Seiurus noveboracensis)* 1 Hooded Warbler* (Wilsonia citrina) 6 Wilson's Warbler* (Wilsonia pusilia) 1 Blue-hooded Euphonia (Euphonia musica) 6 Indigo Bunting* ,asserina cyanea) 1 Black-faced Gras61uit (Tiaris bicolor) 34 Shiny Cowbird (Molothrus bonariensis) I *denotes winter resident Table 2. Banding and longevity information for bird species banded and recaptured in the Guanica Forest, Puerto Rico. See text for explanations of terms. NO. BIRDS NO. OF MEAN RECAP- LONGEST ESTIMATED SPECIES NO. BANDED RECAPTURED RECAPTURES TURE TIME RECAPTURE LONGEVITY Common Ground Dove (Columbina passerina) 50 Mangrove Cuckoo (Coccyzus minor) 9 Puerto Rican Lizard-cuckoo (Saurothera vieilloti) 8 Puerto Rican Tody (Todus mexicanus) 40 Puerto Rican Woodpecker (Melanerpes portoricensis) 11 Caribbean Elaenia (Elaenia martinica) 60 Puerto Rican Flycatcher (Myiarchus antillarum) 56 Red-legged Thrush (Turdus plumbeus) 50 Pearly-eyed Thrasher (Margarops fuscatus) 101 Puerto Rican Vireo (Vireo latimeri) 19 Northern Parula* (Parula americana) 36 Adelaide's Warbler (Dendroica adelaidae) 68 Black-and-white Warbler* (Mniotilta varia) 47 American Redstart* (Setophaga ruticilla) 62 Prothonotary Warbler* (Protonotaria citrea) 3 Ovenbird* (Seiurus aurocapillus) 24 Bananaquit (Coereba flaveola) 291 Stripe-headed Tanager (Spindalls zena) 24 Puerto Rican Bullfinch (Loxigilla portoricensis) 228 Black-cowled Oriole (Icterus dominicensis) 2 Troupial (Icterus icterus) 15 3 3 1-08 2-00 2-07 1 1 2-00 2-00 2-07 2 3 1-08 3-00 3-07 7 15 3-11 13-11 14-06 2 2 2-06 4-00 4-07 6 10 2-00 5-00 5-07 16 29 4-00 11-00 11-07 14 21 3-06 7-00 7-07 18 28 3-08 11-00 11-07 7 14 2-09 8-09 9-04 2 2 4-00 7-00 7-07 10 13 2-05 6-11 7-06 13 19 1-11 4-00 4-07 11 13 1-11 6-11 7-06 1 2 4-00 4-00 4-07 4 4 1-09 2-00 2-07 38 55 2-00 6-00 6-07 4 4 2-01 6-00 6-07 46 63 2-03 7-00 7-07 1 2 1-11 1-11 2-06 2 2 2-11 3-11 4-06 *denotes winter resident IBBA CALL FOR PAPERS The 1989 meeting of the Inland Bird Banding Association will be held on September 8-10, 1989 at the University of Minnesota Raptor Rehabilitation Center on the St. Paul campus. All members and banders are invited and encouraged to submit abstracts for papers or posters covering any aspect of banding, for inclusion in the scientific session to be held on Saturday, September 9th. For information and guidelines, please contact Betsy Jones, Dept. of Veterinary Biology, College of Veterinary Medicine, University of Minnesota, St. Paul, MN 55108, home phone: 612-490-1975, work phone: 612-624-5322. Abstracts are due no later than June 1, 1989.