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WOS 2010 ~ ABSTRACTS p. 30
is needed to determine whether these data indicate that the yellow component of the plumage may be a stronger
selecting factor than the ultraviolet.
P11 S Early successional habitat characteristics and fruit abundance influence stopover use of fall migrating
songbirds. Brad Mudrzynski and Christopher Norment, Dept. Environmental Science and Biology, SUNY College
at Brockport, Brockport, NY 14420
During the 2008 and 2009 fall migrations we used mist nets and visual transects to examine bird use of shrublands
and early successional forests at Iroquois National Wildlife Refuge, NY. The relationship between mist net captures
and transect detections varied across species and habitats, with significant positive relationships for Gray Catbirds
(Dumetella carolinensis) (R2=0.668) and Song Sparrows (Melospiza melodia) (R2=0.384) in shrublands. There
were no significant relationships between the two measures of abundance in forest habitat, or for smaller species
such as warblers in shrublands. Bird abundance was generally greater in shrublands than in early successional
forests and we counted more species using the shrublands, 16, than forest habitat, 9. American Robin (Turdus
migratorius) abundance was positively correlated with shrub cover (p=0.042) and honeysuckle fruit abundance
(p=0.000), while Song Sparrows preferred fields with more red panicled dogwood fruit (p=0.008) and greater
fruiting shrub species richness (p=0.002). These results indicate that in general migrating songbirds prefer
shrublands to early successional forests for stopover habitat; however, exact habitat preferences differ among
species.
P12 An assessment of refueling rates and diet of songbirds during migratory stopover at the Braddock Bay Bird
Observatory. Susan B. Smith, Dept. Biology, Villanova Univ., Villanova, PA 19085
Migrating songbirds rely on stopover sites to rest and replenish body fat and protein but must overcome the
challenges of acquiring food in unfamiliar habitats in order to efficiently refuel before continuing migration. Thus,
the rate at which these birds can replenish energy stores is affected by food availability and quality. I compared
refueling rates and nutritional state of birds captured during spring and fall migration in 2009 at the Braddock Bay
Bird Observatory, an important migratory stopover site on the south shore of Lake Ontario. I measured plasma
concentrations of triglyceride, an indicator of fat deposition, and uric acid, an indicator or dietary protein intake, in
several seasonally frugivorous species that are commonly captured at this site. There were no interspecific
differences in plasma metabolite concentrations during spring; however, during fall Swainson’s Thrushes had
significantly higher plasma triglyceride than White-throated Sparrows and significantly lower plasma uric acid than
White-throated Sparrows and Red-eyed Vireos. I addition, plasma triglyceride was significantly higher and plasma
uric acid was significantly lower during fall compared to spring in Swainson’s Thrushes. Seasonal differences in
triglyceride, but not uric acid, were present in Red-eyed Vireos. These results suggest that there are differences in
dietary protein intake between seasons for some species, most likely representing a switch to frugivory in the fall,
and many birds are able to refuel at a higher rate during fall, possibly due to their consumption of abundant fruit
resources.
P13 Remote radar monitoring of bird activity via the network. Robert C. Beason, Accipiter Radar Corporation,
Orchard Park, NY 14127
Radar is being used increasingly to monitor and record migration and local movements of birds for basic research
and environmental monitoring. Although analog avian radar systems require the presence of an operator to collect
and record data, digital radar systems do not. Digital data can be collected with the radar operating unattended then
reviewed (played back) at the researcher’s convenience. In order to observe activity such as nocturnal migration in
real time, an observer must usually monitor the display directly. Although the raw radar video can be sent to a
remote location through a network, it requires high bandwidth, which is difficult to achieve at remote field locations.
We present a technique to remotely monitor radar detections and tracks of birds in real time. The underlying
mechanism is to reduce the raw radar signals to metadata (i.e., detection and track data) before transmitting them
across the network. Using a radar data server, multiple researchers can simultaneously monitor bird activity from the
same radar, each at a different remote location and each with a display customized to his or her needs. During the
meeting I will demonstrate this capability of real-time monitoring of nocturnal migration by connecting to a radar
located on the highest point of the Niagara escarpment near Fonthill, Ontario, 200 km west of Geneva, NY. This
location provides coverage of the eastern end of Lake Erie and the western end of Lake Ontario. Recorded data from
previous nights’ migration will also be presented.
P14 Annual variation in arrival of long-distant migrants and a comparison of first capture dates and condition
between verified breeders and presumed migrants. Margret I. Hatch, Penn State Worthington Scranton, Dunmore,
PA 18512 and Robert J. Smith, Dept. Biology, Univ. Scranton, Scranton, PA 18510
As part of an on-going study of the ecology of migration at our field site in Northeastern Pennsylvania we examined
annual variation in arrival of six long-distance migrant species that breed at our site. We also examined whether