year previously when she was in oestrus. Now they suddenly appeared, confidently and
without fear of observers, in the heart of the Sonso community. In addition, they associ-
ated closely with each other (M. Emery Thompson et al. in preparation). A fourth adult
female, Flora, who arrived at the same time^43 with two sons, a subadult, Fred, and a
juvenile, Frank, appeared, in contrast, to be frightened of human observers. A fifth new
adult female, Polly, has joined Sonso with her juvenile son Pascal; she too was initially
frightened of observers and, though probably first seen in early 2002, was not described
until 2003.^44 All five of these adult females have settled in to the Sonso community, and,
because the whole community was well known to all observers by the time the first new-
comers arrived, we can be 99% confident that these are immigrant adult females
(Table 5.8). At least six other shy, new parous females have been noted by observers as
of 2004, though we are still waiting to see if they will permanently integrate into Sonso.
Emery Thompson et al. (in preparation) comment on the fact that whereas some
immigrant females are fearful of community members and of human observers, others,
even when they arrive with offspring, are able to enter the Sonso community without
problems with residents or humans. A possible explanation is that some of these females
may be natal females returning after many years absence. This cannot be discounted;
our recognition of allcommunity members dates back only to 1995. These confident
females rapidly become well established and show no problems of habituation to
observers; it is as if they knew the members of the Sonso community already. As seen
above, in recent years several have arrived together.
Could it be that we have actually missed seeing these females, that they are not in fact
new arrivals but had hitherto successfully evaded detection by our field assistants and
students? This is extremely improbable according to Emery Thompson (in preparation)
Inter-community movements of adult females 105Table 5.8: Named immigrants into the Sonso community, 1995–2003.
Name (code) Date of Age–sex In oestrus? With
immigration category offspring?
(age–sex categ.)
Mama (MM) 6/95 AF Yes Muhara (I2F)
Janie (JN) 9/95 SAF Small swelling No
Harriet (HT) 9/96 AF No Hawa (I1M)
Clea (CL) 8/97 SAF No No
Emma (EM) 9/97 Juv/SAF No No
Melissa (ML) 10/01 AF Yes, full Mark (JM)
Sabrina (SB) 10/01 AF Yes, full Sally (SA)
Wilma (WL) 10/01 AF No Willis (JM)
Juliet (JT) 1/02 SAF Yes, full No
Polly (PL) 1/03 AF No Pascal (JM)
Flora (FL) 5/03 AF No Fred (SAM)
Frank (JM)
Key:I2Finfant 2 female; I1Minfant 1 male; other age–sex codes as throughout.
(^43) Flora was first seen on 10 November 2001 but not named until May 2003.
(^44) Polly was named in July 2003.