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WOS 2010 ~ ABSTRACTS p. 16
07 S Development of a bird community integrity index to monitor salt marsh condition at National Wildlife Refuges.
Whitney A. Wiest and W. Gregory Shriver, Dept. Entomology and Wildlife Ecology, Univ. Delaware, Newark, DE
19716, and Hal Laskowski, U.S. Fish and Wildlife Service, Milton, DE 19968
Coastal refuges in the National Wildlife Refuge System protect approximately 1,045,925 acres of salt marsh habitat
in the lower 48 states. Appropriate assessment and monitoring tools are necessary to provide refuge managers with
the ability to determine overall marsh condition in order to maintain or improve the integrity of refuge marshes.
Birds are an appropriate study taxa because they are linked to the overall ecological integrity of their respective
ecosystems and are relatively easy to monitor. During the summers of 2008 and 2009 call-broadcast surveys were
performed at 184 points across nine National Wildlife Refuges and Refuge Complexes on the eastern seaboard. We
tested a bird community integrity (BCI) index to evaluate the marsh bird community integrity at each survey point.
The developed index was based on a previously published index (DeLuca et al. 2004). Species were assigned a
species-specific integrity score based on a combination of species’ attributes (i.e., foraging habit, nesting habit, and
conservation rank). The index evaluated the sum of the detected species’ scores and a component of relative
abundance to calculate point integrity scores. BCI scores were used to compare management treatments of marsh
units within refuges. Significant differences were found between tidally restricted areas and other management
types. We also estimated the percent of habitat cover around each point to evaluate landscape effects on BCI.
08 Winter association of birds with the invasive exotic Brazilian pepper (Schinus terebinthifolius). Jerome A.
Jackson, Dept. Marine and Ecological Sciences, Florida Gulf Coast Univ., Ft. Myers, FL 33965, and Bette J. S.
Jackson, Dept. Biological Sciences, Florida Gulf Coast Univ., Ft. Myers, FL 33965
Brazilian pepper (Schinus terebinthifolius) was introduced to North America in the 1800s and has since become an
abundant invasive exotic in south Florida, forming dense stands of shrubby trees to the exclusion of native
vegetation. We studied bird associations with this plant in southwest Florida and found abundant use of it by
wintering birds as shelter and a source of food. Brazilian pepper blooms through the winter, its tiny white flowers
attracting small insects that pollinate it — and Blue-gray Gnatcatchers, White-eyed Vireos, and wintering wood
warblers, which feed on the insects. During November through February Brazilian pepper produces clusters of red
fruits, which are eaten by Gray Catbirds, Northern Mockingbirds, European Starlings, American Robins, and other
species. Many bird species find shelter within and beneath this tree's dense foliage. Relationships between birds and
Brazilian pepper range from commensal to mutualistic; several species spread the seeds of the plants.
09 S Individuality and recognition in the Great Black-backed Gull, Larus marinus. Christina Masco and Thomas D.
Seeley, Neurobiology and Behavior, Cornell Univ., Ithaca, NY 14850
The Great Black-backed Gull nests in large colonies, occupying territories throughout the breeding season. Territory
boundaries are constantly in contention, and individuals employ specific calls and displays to enforce these
boundaries. One such call is the 'yeow', an aggressive warning call directed at intruders. To test whether gulls are
capable of recognizing each other's calls, I recorded the yeows of 22 individuals and used these recordings as stimuli
in a series of playback experiments. Each playback trial consisted of three conditions in which I varied the source of
the call: mate, neighbor, and stranger. The gulls did not differentiate between mate and neighbor (permutation test, P
= 0.103 and P = 0.187 respectively), but maintained an alert posture in response to a stranger's call significantly
longer than expected (permutation test, P = 0.008). To determine what features of the yeow allow for this
discrimination, I analyzed variation in call structure using spectrographic cross-correlation and principle components
analysis. Caller identity proved to be a strong predictor of variation along the first principle components axis, PCO1
(ANOVA, F-value = 44.50, p < 0.0001). PCO1 showed a strong correlation with yeow duration (R-square = 0.83, p
< 0.0001), suggesting that much of the individual variation among these gulls lies call duration, and this parameter
may be the basis for recognition. Considering the prevalence of intraspecific predation in the Great Black-backed
Gull colonies, the ability to detect unfamiliar calls is highly adaptive.
10 S Influence of adult age on Rose-breasted Grosbeak nestling provisioning rates in stands harvested by single-tree
selection. Sonya Richmond and J. Malcolm, Faculty of Forestry, Univ. Toronto, Toronto, ON M5S 3B3, E. Nol,
Dept. Biology, Trent Univ., Peterborough, ON K9J 7B8, and D. Burke, Ministry of Natural Resources, London, ON
N6E 1L3
We conducted this study to test whether younger, less experienced Rose-breasted Grosbeaks were able to provide
their nestlings with as much food as older, more experienced adults, both in stands harvested by single-tree selection
and in uncut sites. We compared 1) nestling provisioning rates (#trips/nestling/hr), 2) prey load size, and 3) the
proportion of nestling provisioning and nest attendance contributed by after-second-year (ASY) males and secondyear
(SY) males in cut versus uncut sites. We monitored 87 nests in eight harvested and four unharvested hardwood
stands in Algonquin Provincial Park during 2007 and 2008. Nestling provisioning rates, prey load sizes, and the
proportion of nestling provisioning and nest attendance contributed by males did not significantly differ in harvested
and unharvested stands, so nests were pooled for comparison of these parameters between nests with older versus