Population structure of red-cockaded woodpeckers in south Florida: RAPDs revisited

Authors


  • This updated work on woodpecker RAPDs represents the ongoing interest of Susan Haig in elucidating structure and viability of small populations. Reed Bowman is the director of the Applied Avian Biology Lab at Archbold Research Station and is interested in avian population dynamics at local and regional scales. Tom Mullins is the manager of the FRESC Laboratory for Conservation Genetics and prepared the RAPDs for analyses.

Tel.: +1–541-750-7482; Fax: +1–541-758-7761; E-mail: HaigS@FSL.ORST.EDU

Abstract

Six south Florida populations of the endangered red-cockaded woodpecker (Picoides borealis) were sampled to examine genetic diversity and population structure in the southernmost portion of the species' range relative to 14 previously sampled populations from throughout the species range. Random amplified polymorphic DNA (RAPD) analyses were used to evaluate the populations (n= 161 individuals, 13 primers, one band/primer). Results suggested that south Florida populations have significant among-population genetic differentiation (FST= 0.17, P < 0.000), although gene flow may be adequate to offset drift (Nm= 1.26). Comparison of Florida populations with others sampled indicated differentiation was less in Florida (FST for all populations = 0.21). Cluster analyses of all 20 populations did not reflect complete geographical predictions, although clustering of distant populations resulted in a significant correlation between genetic distance and geographical distance. Overall, results suggest populations in south Florida, similar to the remainder of the species, have low genetic diversity and high population fragmentation. Exact clustering of distant populations supports the ability of RAPDs to differentiate populations accurately. Our results further support past management recommendations that translocations of birds among geographically proximate populations is preferable to movement of birds between distant populations.

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