Using the habitat preferences of painted buntings (Passerina ciris) to guide restoration inititiatives on a developing barrier island in South Carolina

Background/Question/Methods

Habitat loss and degradation are major causes for the decline of many songbird species. The decline in migratory songbirds was originally blamed primarily on habitat loss in the tropics. However, studies have shown that habitat loss and fragmentation on breeding grounds also play a substantial role.  One species, the painted bunting (Passerina ciris) has seen declines of over 60% from 1966-1995, or 3.5% annually, according to Breeding Bird Surveys, mostly due to habitat losses. Because of this decline, the painted bunting has been given high priority by many conservation organizations. 

Kiawah Island, SC is a breeding site for painted buntings from April to October.  However, this barrier island is developing at a rapid rate.  Therefore, given people’s affinity for this charismatic bird, we used the habitat preferences of painted buntings to guide restoration initiatives on Kiawah Island and to promote homeowner financed restoration.  To do this, we used radio telemetry to locate the birds and vegetation sampling techniques to quantify the areas they chose.  Specifically we wanted to: 1) determine habitat use and preferences of painted buntings on Kiawah Island (including any tolerance of and/or preferences for developed areas), 2) identify territory size, to guide land preservation efforts, and 3) determine nesting habitat requirements associated with fecundity levels.

Results/Conclusions

We caught 64 birds (Sex: M-32, F-27, Unk-5; Age: ASY-50, SY-9, HY-3, U-2) at residential feeders.  Both sexes and all age classes showed a preference for edge between maritime shrub-scrub forest and marsh.  Males sang from emergent canopy trees, and females utilized mid-story shrub/tree species.  Mean activity heights of males differed significantly from those of females and birds of unknown sex (ANOVA F = 70.78, P = < 0.001).  There were no significant differences for ground cover, midstory, or canopy structure preferences.  Therefore, similar vegetation structure could benefit males, females, adults, and young buntings alike.  Nests were predominantly found in the mid-story, either in shrubs or Spanish moss (Tillandsia usneoides; n = 21; mean nest height = 2.9 m., 4 successful).  Our data suggest that restoration of developed homestead should focus on increasing mid-story habitats.