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THE WILSON JOURNAL OF ORNITHOLOGY • Vol. 124. No. 2. June 2012 
FIG. I. Representative path of a wing-flagged male 
Saltmarsh Sparrow observed for I hr patrolling its home 
range (male OAGIJ. 10 Jim 1985). The male spent all its 
time during this period watching from perches. Hying 
between perches, and occasionally singing from perches or 
in flight. Large tilled circle: First observation; lines: flight 
paths: small filled circles: lookout or song posts; small bar 
final observation; scale bar: 10 m. 
We assessed male dispersion in relation to nest 
stage by a graphical method. We assumed that 
males can ascertain the breeding condition of 
receptive females, and predicted their distribu¬ 
tions would be related to the reproductive states of 
females. Thus, they would be concentrated around 
nests under construction or in the process of 
receiving eggs. We plotted nests and locations of 
b.rds on grid maps. We used the Poisson 
distribution to calculate a coefficient of disper¬ 
sion, D t , the ratio of observed variance to mean 
Rohlf n .QQs! °S UITence in sma " P |ots (Sokal and 
Rohlf 995). We tested the significance of the 
observed distribution's departure from random 
dispeiston with Chi-square goodness of fit 
analyses (Zar 1984, Brower et al. 1990 ) 
Saltmarsh Sparrows have a large cloaeal protu¬ 
berance (cp), which may be used as an index or 
sperm competition (Birkhcad et al. 1993). The 
fnsha^fm 6 k SaUmarsh Sparrows is cylindrical 
m shape from base to top. as confirmed by diameter 
weesZTj" ° n aSamp,e of Protuberances. Thus, 
e estimated cp size (min') as the volume of •, 
cinder (Briskie 1993,. We examined cp “L 
year r m r'r 8 "’“'p ba " dcd durin « halch- 
calendTe f “ h,nc,ion ° f ^ measured as 
calendar year classes I to 5. Sample sizes were 
versus oTderT T" !, year * and Wc spared first-year 
We used ' SPS T'v '" * ' W m C laMifica 11 on ■ 
notation follows Sokal and Rohlf (1995) and the 
rejection level was 0.05. Means are reported with 
standard errors. 
RESULTS 
Male Mate-searching Behavior .—Males spent 
about 75% of their time from 0500 to 1000 his 
patrolling their home ranges (n = 5,205 unit 
observations witnessed during 173 hrs of timed 
periods). They roamed over circumscribed area' 
(Fig. I) within their home ranges, spending 
47.4% of their time on lookout. 16.8% singing. 
16.3% in sexual-social interactions, 12.2% in 
Rights (including flight-singing), and 7.3% in 
unknown activities. Mean duration of lookout 
sessions was 27.0 ± 1.28 sec per perch (w = 417), 
anil of singing bouts (on I or more consecutive 
perches and song flights between them) was 16.5 
1 1.15 sec (n = 203). The morning roaming 
behavior was associated with male-female and 
male-male meetings and appeared to be searching 
behavior. Males also searched the ground, fre¬ 
quently emerging and peering from the top of llie 
grass, then disappearing into the turf again. 
Types of Social Interactions.—We recorded 
1,265 inter and intrasexual encounters based on 
band combinations or behavioral identifications 
during 173 hrs of timed observations (Table I)- 
Male-female interactions were overtly or appar¬ 
ently sexual in nature. Male-male interactions 
mostly involved perch takeovers or meetings with 
any more distant sparrow that turned out to be 
other male Saltmarsh Sparrows. 
Male-female Interactions.—We observed 593 
male-female encounters (Table I) in which a 
female solicited copulation, attacked or chased a 
male, or fought with a male in male-initialed 
meetings. One or more males met a female on the 
ground or joined a flying female, at times striking 
or grabbing her in the air and knocking her to the 
ground. A male that met a female on (he ground 
usually attempted to mount her immediately, or 
stayed on the sidelines while the pounce effort of 
another male proceeded. 
typically, intersexual encounters witnessed 
from platform blinds were meet-and-pounee 
encounters. Sixty-five percent of these interac¬ 
tions (range = 56.6-79.0) involved a single male 
and female. The other cases consisted of iwo lo 
seven males that met one female. Usually one 
(-'90% of cases) or occasionally two or three 
males at the multi-male meetings attempted to 
mount the female. Up to four or five males in 
