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Scent‐Marking Behaviour in a Pack of Free‐Ranging Domestic Dogs

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Most mammals scent‐mark, and a variety of hypotheses have been put forward to explain this behaviour. Most of our knowledge about scent marking in domestic dogs comes from studies carried out on laboratory or companion dogs, while few studies have been carried out on free‐ranging dogs. Here, we explored the functional significance of different scent‐marking behavioural patterns in a pack of free‐ranging domestic dogs by testing two non‐exclusive hypotheses: the indirect territorial defence and the dominance/threat hypotheses. Through direct observation, we recorded the locations of dog scent marks (urination, defecation and ground scratching) and information regarding the identity and posture of the marking animal. We found evidence that markings are used by dogs to form a ‘property line’ and to threaten rivals during agonistic conflicts. Both males and females utilized scent marking to assert dominance and probably to relocate food or maintain possession over it. Raised‐leg urination and ground scratching probably play a role in olfactory and visual communication in both males and females. Urinations released by females, especially through flexed‐leg posture, may also convey information about their reproductive state. Finally, our observations suggest that defecation does not play an essential role in olfactory communication among free‐ranging dogs and that standing and squat postures are associated with normal excretion. Our results suggest that many of the proposed functions of marking behaviours are not mutually exclusive, and all should be explored through detailed field and laboratory studies.
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RESEARCH PAPER
Scent-Marking Behaviour in a Pack of Free-Ranging Domestic
Dogs
Simona Cafazzo*, Eugenia Natoli& Paola Valsecchi*
* Dipartimento di Biologia Evolutiva e Funzionale, Universita
`degli Studi di Parma, Parma, Italy
Azienda USL Roma D, Area Dipartimentale Sanita
`Pubblica Veterinaria, Rome, Italy
Correspondence
Simona Cafazzo, Dipartimento di Biologia
Evolutiva e Funzionale, Universita
`degli Studi
di Parma, via G.P. Usberti 11/A, 43100 Parma,
Italy, and via Gasperina 300, 00173 Rome,
Italy.
E-mail: simona.cafazzo@inwind.it
Received: June 20, 2011
Initial acceptance: September 16, 2011
Final acceptance: July 5, 2012
(M. Herberstein)
doi: 10.1111/j.1439-0310.2012.02088.x
Abstract
Most mammals scent-mark, and a variety of hypotheses have been put
forward to explain this behaviour. Most of our knowledge about scent
marking in domestic dogs comes from studies carried out on laboratory or
companion dogs, while few studies have been carried out on free-ranging
dogs. Here, we explored the functional significance of different scent-
marking behavioural patterns in a pack of free-ranging domestic dogs by
testing two non-exclusive hypotheses: the indirect territorial defence
and the dominance/threat hypotheses. Through direct observation, we
recorded the locations of dog scent marks (urination, defecation and
ground scratching) and information regarding the identity and posture of
the marking animal. We found evidence that markings are used by dogs
to form a ‘property line’ and to threaten rivals during agonistic conflicts.
Both males and females utilized scent marking to assert dominance and
probably to relocate food or maintain possession over it. Raised-leg urina-
tion and ground scratching probably play a role in olfactory and visual
communication in both males and females. Urinations released by
females, especially through flexed-leg posture, may also convey informa-
tion about their reproductive state. Finally, our observations suggest that
defecation does not play an essential role in olfactory communication
among free-ranging dogs and that standing and squat postures are associ-
ated with normal excretion. Our results suggest that many of the proposed
functions of marking behaviours are not mutually exclusive, and all
should be explored through detailed field and laboratory studies.
Introduction
Scent marking may be defined as the deposition of
odour by urination, defecation or the release of glan-
dular secretions (Kleiman 1966). Scent marking may
communicate detailed information about the scent
source, including social status, age, sex and reproduc-
tive state, group composition and individuality (e.g.
Ralls 1971; Gorman & Trowbridge 1989; Smith et al.
2001).
Most of our knowledge about scent marking in
domestic dogs (Canis lupus familiaris) comes from stud-
ies carried out on laboratory or companion dogs.
Urinary behaviour in domestic dogs is sexually dimor-
phic (Beach 1974; Ranson & Beach 1985). Adult
males urinate more frequently than do females and
are more likely than females to direct their urine at
specific targets (Martins & Valle 1948; Bekoff 1979a;
Ranson & Beach 1985). In addition, adult males typi-
cally raise a hind leg to urinate, while adult females
usually squat (Martins & Valle 1948; Beach 1974).
While urination clearly has the physiological function
to empty the bladder in both sexes, its role in scent
marking is thought to be more important in male dogs
than in female dogs (Martins & Valle 1948; Bekoff
1979a; Pal 2003). Indeed, Kleiman (1966) suggested
that female dogs mark with urine only around the
time they are in oestrus. Lisberg & Snowdon (2009,
2011) observed that, outside of oestrus, both high-
status males and females urinated, investigated urine
and countermarked more than same-sex dogs with
lower status. Moreover, males and females were
Ethology 118 (2012) 1–12 ©2012 Blackwell Verlag GmbH 1
Ethology
equally likely to countermark and investigate urine
(Lisberg & Snowdon 2011).
A study (Pal 2003) carried out using direct observa-
tion of urine-marking behaviour of free-ranging
domestic dogs further showed that urine marking was
displayed especially during territorial defence. Ques-
tions remain, however, regarding the function of
urine-marking behaviour and other scent-marking
behaviours, especially in relation to different social
classes within a pack.
In the current study, we explored the functional
significance of different scent-marking behaviours in
a pack of free-ranging domestic dogs living in a subur-
ban environment. We focused on three different
behavioural patterns of marking: urination, defeca-
tion and ground scratching. Scent marking by urina-
tion is a common practice in the family Canidae (e.g.
Scott & Fuller 1965; Kleiman 1966; Beach 1974; Fox
et al. 1975; Peters & Mech 1975; Dunbar 1977, 1978;
Bekoff 1979a; Wells & Bekoff 1981; Gese & Ruff 1997;
Allen et al. 1999; Pal 2003; Zub et al. 2003). Defeca-
tion and ground scratching can also serve as scent
marking in canids (e.g. wolves, Canis lupus: Peters &
Mech 1975; Barja & De Miguel 2004; coyote, Canis la-
trans: Wells & Bekoff 1981; Gese & Ruff 1997). Scats
often are left in conspicuous locations, such as on
rocks, plants and trail junctions, probably increasing
their effectiveness as visual and olfactory marks.
Ground scratching often occurs after defecation or
raised-leg urination, and it may serve as a chemical
signal and as a visual signal (Peters & Mech 1975;
Bekoff 1979b; Bekoff & Wells 1986). The chemical
component may involve either scent deposited from
interdigital glands or the dispersion of olfactory cues
from deposited urine or faeces (Peters & Mech 1975;
Fox & Cohen 1977). The visual component may
involve the act of ground scratching or the marks left
on the ground by such scratching (Kleiman & Eisen-
berg 1973; Bekoff 1979b). Ground scratching has not
been reported to follow squat urination and appears
to be performed predominantly by high-ranking
males (e.g. wolves: Peters & Mech 1975; coyotes: Gese
& Ruff 1997).
Our aim was to test two non-exclusive hypotheses
related to the function of scent marking by free-rang-
ing domestic dogs: the ‘indirect territorial defence
hypothesis’ and the ‘dominance/threat hypothesis’.
Animals may scent-mark for the purpose of defend-
ing food resources or territories, thereby reducing
fights with conspecifics (indirect territorial defence
hypothesis). Scent marks could work as a chemical
‘keep out sign’, which would deter or intimidate
intruders (Wyatt 2003), or scent marks allow an
intruder to identify the territory owner by matching
scent marks encountered in the territory with the
scent of individuals encountered (Gosling (1982).
Identification of the territory owner by the intruder
can help to avoid escalated conflicts between them
and thus is beneficial to both parties (Gosling &
Roberts 2001). If the costs of scent-marking the terri-
tory (in terms of time and energy and perhaps
increased vulnerability to predators) are lower than
the costs of attacking an intruder, scent marking
becomes an economic strategy for territorial defence
(Gosling 1982, 1986; Gosling & Roberts 2001).
According to both scent fence and scent-matching
mechanisms, scent marking should be concentrated
in areas where scent marks are most likely to be
encountered by an intruder, that is, along the territo-
rial boundary (Gosling 1982). Studies on different
mammalian taxa have supported this prediction (e.g.
wolves, Peters & Mech 1975; Rothman & Mech 1979;
Zub et al. 2003; tigers, Panthera tigris: Smith et al.
1989; marmots, Marmota spp.: Boero 1995; Blumstein
& Henderson 1996; blind mole-rats, Spalax ehrenbergi,
Zuri et al. 1997; coyote, Wells & Bekoff 1981; Gese &
Ruff 1997; Allen et al. 1999; ethiopian wolves, Canis
simensis, Sillero-Zubiri & Macdonald 1998).
Ralls (1971) hypothesized that social mammals tend
to mark frequently in any situation where they are
both intolerant of and dominant to other members of
the same species. In other words, they mark when
they are likely to attack another member of the same
species and are likely to win if they do attack. Such
behaviour may occur in territorial defence, but it will
not necessarily be restricted to territorial situations. In
fact, scent marking may function to communicate
dominance status among group members, thus reduc-
ing the need for costly fights. The dominance/threat
hypothesis has received support from several studies
on scent marking in mammals (e.g. Walther 1978;
Gosling & Roberts 2001; Miller et al. 2003; Bonanni
et al. 2007).
In this study, we aim to test the general prediction
that, if scent marking is used to communicate indirect
defence of territory (territorial defence hypothesis), dogs
would mark more frequently along the periphery of the
territory than in its interior (prediction 1a); moreover,
dogs are expected to mark more frequently at strategic
places, such as crossroads, where potential intruders are
most likely to encounter marks (prediction 1b).
According to the dominance/threat hypothesis, we
predicted that dominant animals would mark more
frequently than subordinate animals (prediction 2a).
We also may predict a positive correlation between
scent marking and aggressive behaviour (prediction
Ethology 118 (2012) 1–12 ©2012 Blackwell Verlag GmbH2
Scent-Marking Behaviour in Domestic Dogs S. Cafazzo, E. Natoli & P. Valsecchi
2b) and an increase in marking rate prior to or during
agonistic interactions than during non-agonistic
encounters (prediction 2c).
Finally, to confirm and extend the results of previ-
ous research, in this study, we also asked the follow-
ing questions: is the rate and posture of scent marking
influenced by sex of dogs? Do dogs scent-mark at
different rates in different social contexts and in differ-
ent places? Do female dogs use urination, ground
scratching and defecation to mark their territory or to
indicate dominance?
Methods
Study area
The research was carried out in a suburban environ-
ment situated in the south-western outskirts of Rome,
Italy (41°50N, 12°23W; elevation: about 60 m). The
study area was about 300 ha and was delimited to the
north, west and south by roads with heavy traffic and
to the east by cultivated areas.
The south-west sector was urbanized, although
not densely populated. The north-east sector was
mainly occupied by a nature reserve called ‘Tenuta
dei Massimi’.
The habitat in the reserve consists mainly of open
grasslands with interspersed wooded areas (see
Bonanni et al. 2010a for a more detailed description).
All dog packs had free access to virtually every part
of the study area. Nevertheless, the individuals of the
pack studied mainly frequented the area of the Natu-
ral Park where the dense vegetation of the wooded
areas offered good shelter for the animals, especially
for lactating females and their puppies. However, they
frequently approached a central road crossing the
study area, especially in the early morning, to feed
on the food (mainly meat from a slaughterhouse)
brought every day by volunteer dog caretakers.
Subjects
The dog pack studied belonged to a population of
about 100 adult animals inhabiting the study area. All
dogs were mediumsized to large mongrels, and there
was not a recognizable predominant breeding type
(Cafazzo 2007). With very few exceptions, dogs were
not socialized to humans although they were depen-
dent on humans for food provisioning. All dogs of the
pack were individually recognized by coat colour and
pattern, hair length and body size; they were sexed by
genital morphology (for a detailed description, see
Cafazzo et al. 2010 and Bonanni et al. 2010a,b).
Observations of this pack of dogs began in Mar.
2005. We had direct knowledge of age in dogs 2 yr
and younger. The ages of the remaining dogs were
assessed by estimating body size and general appear-
ance (e.g. white hair on the muzzle) as well as tooth
wear (e.g. Gier 1968) and eruption (Kirk 1977) during
capturing and immobilization procedure (see Cafazzo
et al. 2010 for details of age estimation). Dogs were
thus reliably classified as juveniles (6 mo to 1 yr),
subadults (12 yr) and adults (more than 2 yr). At
the start of the research, the dog pack consisted of 27
individuals. Owing to some deaths, births and disap-
pearances of some individuals during the period of
observation (see. Cafazzo et al. 2010 for a detailed
description), the pack size ranged from 25 to 42 indi-
viduals. The final statistical analysis was applied to 27
dogs: six adult males, five adult females, four subadult
males, one subadult female, six juvenile males and
five juvenile females.
Behavioural observations
The study began in Apr. 2005 and lasted until the end
of May 2006. Data were collected in three different
contexts: in the presence of food, when receptive
females were courted by males (and food was not
present), and in the absence of sources of competition
(i.e. when food was not present and outside the oes-
trus period) for a total of 282.53 h of recording. Data
collection was carried out following Altmann’s (1974)
methods: focal animal sampling method was used in
the absence of sources of competition, whereas the
focal subgroup sampling method was used in the
presence of food and receptive females.
For each urination, defecation and ground scratch-
ing performed by the focal animals, the type, time and
location of the behaviour were recorded. According to
Kleiman (1966), urinations were classified as scent-
marking events rather than eliminations; when urine
was released in small quantity following olfactory
investigation, it was orientated towards a conspicuous
substrate (plants, rocks, food, walls, car wheels, etc.),
elicited by familiar landmarks, novel odours or objects
and conspecifics marks (usually dogs marked just over
or some distance away from investigated spots). Uri-
nation posture recorded included: (1) raised-leg uri-
nation (one hind leg is raised off the ground, whether
or not there is a vertical target); (2) flexed-leg urina-
tion (the dog squats and elevates one hind leg slightly
forward or directly under the body); (3) standing uri-
nation (dogs do not squat but they stand with their
hind legs straight); (4) squat urination (the dog’s hind
part is lowered, the hind legs are bent under the body
Ethology 118 (2012) 1–12 ©©2012 Blackwell Verlag GmbH 3
S. Cafazzo, E. Natoli & P. Valsecchi Scent-Marking Behaviour in Domestic Dogs
and the urogenital region comes close to the ground).
We also recorded all events of defecation. Scats were
considered as true marking cues if they were depos-
ited following olfactory investigation at conspicuous
or raised sites (Kleiman 1966). Finally, we also
recorded all events of ground scratching, the alternate
movements of the legs through which the dog
scratches the ground, sending grass and earth flying
backward; it often occurs after raised-leg urination
and defecation (Rothman & Mech 1979; Zub et al.
2003).
The individual measure of behavioural patterns
was corrected for animal observation time because
the latter varied between individuals.
In the absence of sources of competition, we also
recorded the location of the focal animal using the
instantaneous- sampling method (60-s intervals)
(Altmann 1974). Thus, we could estimate for each
dog, the time spent in the following zones: along the
territorial boundaries, outside the territory, at feeding
sites, at denning sites and somewhere else in the
territorial area.
Home range and territory sizes
To analyse the spatial distribution of scent marking,
we calculated the sizes of the home range and of the
defended area by applying the minimum convex poly-
gon method (Southwood & Henderson 2000). Home
range was examined by plotting the locations of the
animals sighted covering fixed paths everyday twice
per day. We totalled 150.65 ±19.95 sightings for each
dog during 197 days of observation. Home range size
was estimated by drawing a convex polygon connect-
ing the outermost sightings and computing its area,
including inner buildings and fenced areas.
As a counterevidence of the territory size esteem,
the locations where pack members clearly won the
territorial fights against intruders were plotted. A ter-
ritorial fight was defined as an agonistic encounter
between pack members under study and dogs belong-
ing to neighbouring social packs. The pack members
were considered winning the agonistic encounter
when they managed to drive away the intruders.
Statistical analysis
By using data on the direction of submissive behav-
iour observed between dogs, we could arrange all
individuals belonging to the pack studied in a linear
dominance hierarchy whose details are described
elsewhere (Cafazzo et al. 2010).
To test the predictions generated from the indirect
territorial defence hypothesis, we expressed the indi-
vidual marking rate as the number of markings
recorded in each zone divided for the time spent in
the same zone. Then, we compared the individual
marking rate displayed along territorial boundaries (at
crossroads or not) with those displayed both outside
(about 100 m beyond the territorial boundaries) and
inside the territorial area. A scent mark was classified
as a boundary mark when it occurred within 50 m of
the territorial boundaries. We also compared the
hourly rate of scent markings observed at denning
sites, feeding sites (when no food was present) and
somewhere else to analyse the spatial distribution of
scent marking inside the territorial area. For these
analyses, we only considered the scent markings
recorded in the absence of sources of competition
(scent marking that occurred during territorial conflict
or in the presence of food or oestrus females were not
included) because the spatial distribution of scent
marking observed in the other two contexts (during
feeding and courting) was influenced by the location
of feeding sites and by movements of receptive
females.
As in this dog pack the dominance rank, the rate of
aggressive behaviour and the age of the individuals
were correlated (see Cafazzo et al. 2010), we applied
a principal components analysis (PCA) to replace the
mentioned three original variables with new uncorre-
lated component variables, linear combinations of the
original variables, called principal components or fac-
tors. Then, we tested the dominance/threat hypothe-
sis by correlating the hourly rate of marking
behaviours to the PCA components that explained
most of the variation in the data.
By comparing the rate of scent marking during an
agonistic conflict with the rate of marking during
non-agonistic interactions, we verified the relation
between marks and the aggressive motivation towards
other dogs. For this analysis, we separately considered
interactions between pack members and with dogs
from other packs.
We tested the hypotheses and investigated the
relationship between scent marking and sex and
social context using two-tailed non-parametric sta-
tistical tests [Wilcoxon signed-ranks test (t), Mann
Whitney U-test, and Spearman rank correlation
(r
s
)], (STATISTICA 7.1 edition, StatSoft Italy s.r.l.
2005). Probability level for rejection of the null
hypothesis was set at p <0.05. Media and range
of behavioural patterns analysed are listed in
Table 1.
Ethology 118 (2012) 1–12 ©2012 Blackwell Verlag GmbH4
Scent-Marking Behaviour in Domestic Dogs S. Cafazzo, E. Natoli & P. Valsecchi
Results
Home range and territory
Although some subgroups sometimes covered longer
distances than other subgroups, pack members usu-
ally moved all together throughout the area, and indi-
viduals’ home ranges clearly overlapped within the
pack. The home range pack size was calculated as
xof
the individuals’ home ranges (N =27), and it aver-
aged 60.98 ±9.18 ha.
Territorial boundaries were assumed to be the
same for all members of the pack because it has
been observed that all pack members cooperated for
territorial and resources defence against intruders
from other neighbouring social packs (Bonanni et al.
2010a). Group territory size measured 22.14 ha and
its boundaries were inside the boundaries of the home
range. We defined the periphery of the territory as a
zone within 50 m of the territorial boundaries. This
periphery or boundary zone comprised about 21% of
the area of territory. All dens, resting and feeding sites
were located inside the territory and never in the
periphery.
Scent-marking behaviours: influence of sex and
context
We recorded a total of 782 urinations, 143 ground
scratches and 89 defecations during 282.53 h of
observation. Of 782, 589 were raised-leg, 52 flexed-
leg, 36 standing and 105 were squat urinations.
All squat and standing urinations were identified as
simple eliminations because they were never pre-
ceded by olfactory investigation, and they were
released on inconspicuous substrates (the ground).
For males, the incidence of marking was greater than
the incidence of simple elimination (Wilcoxon signed
rank test: t=1.00, z=3.46, n =16, p =0.0005). On
the contrary, females more frequently displayed
normal excretion than marking (t=7.00, z=2.09,
n=11, p =0.04).
Of 89 defecations recorded, only nine scats have
been considered to have a communicative function
because they were deposited following investigation
on raised sites (on rocks or plants); moreover, these
nine scats were deposited at crossroads. The incidence
of scent marking via urination was greater than
the incidence of scent marking via defecation.
The proportion of different postures displayed dur-
ing urination varied among the two sexes. Males
typically performed raised-leg urination (N =581;
94.01%), while they rarely displayed standing urina-
tion posture (N =36; 5.83%); only a juvenile male
was observed displaying a squat posture (N =1,
0.16%). Females rarely displayed raised-leg urination
(N =8, 4.88%), while they usually displayed flexed-
leg (N =52, 31.71%) and squat urination postures
(N =104; 63.42%).
The sex of dogs influences the frequency of scent
marking via urination: the marking rate via urination
was higher for males than for females (Mann
Whitney U-test: U=42.5, n1 =16, n2 =11, p =
0.023). Females included a different representation of
age categories than males because only one subadult
female was observed. As this could skew the results,
we also compared only adult dogs when looking at
male vs. female marking, and we found again that
males marked via urination more frequently than
females (U=2.37, n1 =6, n2 =5, p =0.017).
The hourly rate of raised-leg urination displayed by
males was higher during feeding than in the presence
of receptive females; although the male raised-leg uri-
nation rate was higher in the absence of sources of
competition than in the presence of food, the differ-
ence was not significant (Table 2). Male raised-leg
urination rate was also higher in the absence of
sources of competition than in the presence of recep-
tive females (Table 2). Males ground-scratched more
frequently in the presence of food than in the pres-
ence of receptive females and even more frequently
in the absence of sources of competition (Table 2).
Standing urination was never observed in the pres-
ence of receptive females and its hourly rate did not
differ across the other two social contexts (Table 2).
Females displayed flexed-leg urination more fre-
quently during their oestrus than in the presence of
food and in the absence of sources of competition;
moreover, the hourly rate of flexed-leg urination was
higher in the presence of food than in the absence of
Table 1: Media and range of hourly rates of behavioural patterns
considered
N Media Minimum Maximum
Urination marking displayed
by males
16 0.72 0.13 2.67
Urination marking displayed
by females
11 0.27 0.00 0.72
Ground-scratching displayed
by all dogs
27 0.11 0.00 0.48
Standing urination displayed
by males
16 0.07 0.00 0.22
Squat urination displayed
by females
11 0.47 0.12 0.71
Defecation displayed by
all dogs
27 0.11 0.03 0.19
Ethology 118 (2012) 1–12 ©©2012 Blackwell Verlag GmbH 5
S. Cafazzo, E. Natoli & P. Valsecchi Scent-Marking Behaviour in Domestic Dogs
sources of competition (Table 3). Squat urination
hourly rate did not differ among the three social con-
texts (Table 3). All ground scratchings and raised-leg
urinations performed by females were recorded in the
absence of sources of competition.
Test of predictions
Prediction 1
Males scent-marked more frequently along territorial
boundaries and in the interior of the territory than
in rest of their home range (Table 4), while females
were never observed marking outside the territorial
area.
The hourly rate of scent marking via urination
along territorial boundaries vs. the interior was
influenced by the sex of dogs. Males scent-marked
via raised-leg urination along territorial boundaries
at a higher frequency compared with the interior
(Table 4) and mainly at the crossroads along territo-
rial borders (t=5.00, z=2.98, n =16, p =0.003). In
contrast, females scent-marked via flexed-leg urina-
tion more frequently inside the territorial area than
along the boundaries (Table 4). All events of raised-
leg urination by females (N =8) were observed along
the periphery at the crossroads. Also males scent-
marked via raised-leg urination mainly at the cross-
roads along territorial borders (t=5.00, z=2.98,
n=16, p =0.003). Inside the territory, females scent-
marked more frequently at denning sites than at feed-
ing sites and somewhere else (Table 5), even if the
urine-marking rate was higher at feeding sites than
somewhere else the difference was not significant
(Table 5). On the contrary, the urine-marking rate of
males was higher at feeding sites than denning sites
and somewhere else (Table 5), while it did not differ
between denning sites and somewhere else (Table 5).
Males ground-scratched along territorial boundaries
at a higher frequency compared with the inside
(t=0.00, z=2.67, n =16, p =0.007) and outside of
territory (t=0.00, z=2.64, n =16, p =0.006), but no
difference was found between the ground-scratching
rate recorded inside and outside the territory (t=
11.00, z=1.21, n =16, p =0.36). Females scratched
the ground only along territorial boundaries following
raised-leg urination.
Scent marking via defecation was displayed only by
the alpha male along territorial boundaries. Of 11
events of defecation displayed by the alpha male, 9
(81.82%) were deposited along territorial boundaries
at crossroads and mainly on conspicuous or high
substrates (rocks and plants; N =7, 77.78%).
All elimination events and the 80 events of defeca-
tions identified as normal excretions were randomly
distributed: along territorial boundaries, in the inte-
rior of the territory and in the rest of the home range
(Table 6).
Prediction 2
For males, the first factor of the PCA alone explained
86.66% of the total variance in the data (Fig. 1a):
Table 2: We used the Wilcoxon signed-ranks test to compare the hourly rates of raised-leg urination, ground scratching and standing urination
performed by males, among three competitive contexts: in the absence of sources of competition, in the presence of food and during courting of
receptive females
Raised-leg urination Ground scratching Standing urination
tzptzptz p
Absence of sources of competition vs. presence of food (n =16) 49 0.98 0.32 5.00 2.07 0.04 36 0.66 0.50
Presence of food vs. during courting (n =16) 0.00 3.40 0.001 1.00 2.38 0.02 a a a
Absence of sources of competition vs. during courting (n =16) 0.00 3.40 0.001 0.00 2.67 0.01 a a a
a
Standing urination was never observed in the presence of receptive females.
Table 3: We used the Wilcoxon signed-ranks test to compare the hourly rates flexed-leg urination and squat urination performed by females among
three competitive contexts: in the absence of any sources of competition, in the presence of food and during courting by males
Flexed-leg urination Squat urination
tzptzp
Absence of sources of competition vs. presence of food (n =11) 3.00 2.10 0.04 15.00 1.60 0.11
Presence of food vs. during courting (n =7) 0.00 2.37 0.002 11.00 0.50 0.51
Absence of sources of competition vs. during courting (n =7) 0.00 2.36 0.002 5.00 1.52 0.13
Ethology 118 (2012) 1–12 ©2012 Blackwell Verlag GmbH6
Scent-Marking Behaviour in Domestic Dogs S. Cafazzo, E. Natoli & P. Valsecchi
males characterized by high negative scores on this
factor were high-ranking older individuals who
displayed a higher frequency of aggressive behaviour.
The second factor of the PCA explained just 12.01%
of the variance (Fig. 1a).
The first factor was negatively correlated with both
urine scent-marking hourly rate (r
s
=0.95, n =16,
p=0.000001) and ground-scratching hourly rate
(r
s
=0.67, n =16, p =0.005) displayed by males.
Therefore, high-ranking old dogs were more aggres-
sive and displayed scent-marking behavioural pat-
terns more frequently than juveniles or subadults.
For females, the first factor of the PCA alone
explained 73.90% of the total variance in the data
(Fig. 1b); the second factor of the PCA explained
24.48% of the variance. Thus, females characterized
by high negative scores for the first factor were high-
ranking old individuals who displayed a higher fre-
quency of aggressive behaviour. Females with high
negative scores on the second factor displayed a
higher frequency of aggressive behaviour (Fig. 1b).
Moreover, these dogs were also younger, on average,
than those that had high negative scores on the first
component. The rate of scent marking via urination
displayed by females was negatively correlated to the
first factor (r
s
=0.88, n =11, p =0.0004), but it
was not correlated to the second factor (r
s
=0.28,
n=11, p =0.41).
Males scent-marked via urination more frequently
during agonistic than non-agonistic interactions with
both other pack members and dogs from other packs
(Table 7). Moreover, the rate of marking during ago-
nistic interactions with pack members was lower than
during agonistic interactions with dogs from other
packs (t=0.00, z=3.30, n =16, p =0.001). Females
also scent-marked via urinations (both flexed-leg and
raise-leg urinations) more often during agonistic than
non-agonistic interactions with both other pack mem-
bers and dogs from other packs (Table 7). However,
for them, the rate of marking during agonistic interac-
tions with pack members and with dogs from other
packs did not differ (t=5.00, z=0.67, n =11,
p=0.5). Finally, the rate of ground scratching was
higher during agonistic than non-agonistic interac-
tions with both pack members and dogs from other
packs (Table 7). Dogs ground-scratched at higher rate
Table 4: We used the Wilcoxon signed-ranks test to compare the hourly rate of raised-leg urination displayed by males (n =16) and the hourly rate
of flexed-leg urination displayed by females (n =11) outside and inside of the territory and along territorial boundaries
Raised-leg urination (n =16) Flexed-leg urination (n =11)
tzptzp
Outside of the territory vs. territorial boundaries 0.00 3.52 0.0004
Territorial boundaries vs. inside of the territory 0.00 3.51 0.0004 0.00 2.20 0.03
Outside of the territory vs. inside of the territory 1.00 2.85 0.0004
Table 5: We used the Wilcoxon signed-ranks test to compare the hourly rate of urine marking displayed by males (n =16) and females (n =11)
inside the territory at different sites: denning sites, feeding sites and somewhere else
Raised-leg urination (n =16) Flexed-leg urination (n =11)
tzptzp
Denning sites vs. feeding sites 0.00 2.98 0.003 0.00 2.22 0.02
Denning sites vs. somewhere else 10.00 1.12 0.26 0.00 2.18 0.04
Feeding sites vs. somewhere else 0.00 2.91 0.004 0.00 1.83 0.07
Table 6: We used the Wilcoxon signed-ranks test to compare the hourly rate of standing urination displayed by males (n =16), squat urination
displayed by females (n =11) and defecation displayed by all dogs (n =27) outside and inside of the territory and along territorial boundaries
Standing urination (n =16) Squat urination (n =11) Defecation (n =27)
tzptzptzp
Outside of the territory vs. territorial boundaries 13.00 0.17 0.87 7.00 1.18 0.24 103.00 0.76 0.45
Territorial boundaries vs. inside of the territory 3.00 1.86 0.07 30.00 0.27 0.79 135.00 1.30 0.19
Outside of the territory vs. inside of the territory 10.00 1.12 0.26 11.00 1.95 0.06 158.00 0.45 0.66
Ethology 118 (2012) 1–12 ©©2012 Blackwell Verlag GmbH 7
S. Cafazzo, E. Natoli & P. Valsecchi Scent-Marking Behaviour in Domestic Dogs
during agonistic interaction with dogs from other
pack than with pack members (t=0.00, z=3.06,
n=27, p =0.002).
Discussion
Indirect territorial defence hypothesis
Our results provide evidence that scent marking by
free-ranging domestic dogs may serve as demarcation
of territorial boundaries according to the territorial
defence hypothesis. Male dogs, as other species of
canids (wolves: Harrington 1981; Asa et al. 1985a,b,
1990; Harrington & Asa 2003; Peters & Mech 1975;
Zub et al. 2003; coyotes: Wells & Bekoff 1981; Gese &
Ruff 1997; Allen et al. 1999), appear to delimit their
territory by means of urine and scratching. Dogs, as
wolves (Zub et al. 2003) and coyotes (Wells & Bekoff
1981), were observed scent-marking especially at
crossroads, where the intrusion of other dogs from
neighbouring packs might be more likely. Neverthe-
less, whether scents alone (i.e. the scent-fence
hypothesis) or the matching between scents and sig-
nallers (territory owners; i.e. the scent-matching
hypothesis) would keep out intruders needs to be
explored. Moreover, as we did not study the scent-
marking distribution pattern of neighbouring dog
packs, we cannot exclude that the concentration of
scent marking along territorial boundaries could
also be caused by dogs countermarking unfamiliar
conspecifics’ urine; this does not necessarily indicate
territory defence as the main function of urine
marking.
Wolves have been observed depositing and accu-
mulating scats at strategic sites (e.g. crossroads, con-
spicuous substrates), probably to increase their
effectiveness as visual and olfactory marks (Barja
et al. 2004). In our dog pack, only the alpha male was
observed scent-marking by means of faeces at cross-
roads, but a real accumulation of scats in this place
has never been observed. As group members collec-
tively defended the territory in agonistic encounters
with intruders, if scats functioned in territorial
defence, a group-wide (rather than ‘alpha only’) use
of scats along boundaries, especially at crossroads,
should be expected. It is not clear why it was per-
formed only by the alpha male.
Contrary to males, female dogs scent-marked
mainly in the interior of the territory. Nevertheless,
the findings that both females and males scent-
marked inside the territory suggest that information
was also conveyed via these internal marks.
Dominance/threat hypothesis
Our results are also consistent with the dominance/
threat hypothesis (Ralls 1971). High-ranking individ-
uals are more likely to display marking behaviour.
(a)
(b)
Fig. 1: Principal components analysis (PCA) results for males (a) and
females (b). The circles shows the correlation between the original vari-
ables and the two new components. (a) Pearson correlations between
factor 1 of the PCA and the original variables were: 0.95 (Age), 0.97
(Hierarchical rank), 0.86 (Rate of aggressive behaviour). Pearson corre-
lations between factor 2 and the original variables were: 0.27 (Age),
0.17 (Hierarchical rank), 0.50 (Rate of aggressive behaviour). (b) Pear-
son correlations between factor 1 of the PCA and the original variables
were: 0.90 (Age), 0.98 (Hierarchical rank), 0.68 (Rate of aggressive
behaviour). Pearson correlations between factor 2 and the original vari-
ables were: 0.42 (Age), 0.12 (Hierarchical rank), 0.74 (Rate of aggres-
sive behaviour).
Ethology 118 (2012) 1–12 ©2012 Blackwell Verlag GmbH8
Scent-Marking Behaviour in Domestic Dogs S. Cafazzo, E. Natoli & P. Valsecchi
Moreover, the frequency of scent marking was clearly
related to aggressive behaviour given that dogs
marked more frequently during agonistic interactions
than non-agonistic interactions between both pack
mates and dogs from other packs. A higher frequency
of territorial marking behaviour performed by high-
ranking individuals was also found in wolves (Mech
1999, 2000; Peterson et al. 2002) and coyotes (Gese &
Ruff 1997), as well as in high-status companion dogs
(Lisberg & Snowdon 2011).
Males urinated raising a leg at higher rates during
conflicts with other dogs, especially against intruders
and along territorial boundaries; females displayed
raised-leg urinations only along territorial boundaries
and more often during agonistic interactions with
intruders. These findings support the idea that this
behavioural pattern may serve both as a mechanism
of border enforcement (as suggested for other species
of canids: coyotes, Gese & Ruff 1997; wolves, Barja
et al. 2004) and as a visual cue to display dominance
or threat to opponents.
The functions of ground scratching
Males scratched the ground mainly after raised-leg
urinations along territorial boundaries; females were
observed scratching the ground only after raised-leg
urinations. Both of them displayed this behaviour,
especially during territorial conflicts. Finally, high-
ranking older individuals scratched the ground more
often than low-ranking younger dogs. These results
highlight the role of ground scratching as a display of
social dominance and as a means of territorial
defence. In fact, scents dispersed during ground
scratching may identify the social status of the signal-
ler and inform intruders of territorial boundaries.
Therefore, from our results, ground scratching in
domestic dogs appears to be an additional visual mark
to reinforce the olfactory cue of urine marking and to
intimidate opponents.
Influence of sex
The rate of marking was higher in males than in
females as observed in other studies carried out on
free-ranging dogs (Bekoff 1979a; Pal 2003), laboratory
(Dunbar 1977, 1978) and companion dogs (Lisberg &
Snowdon 2011) as well as on wolves (Mech 2006).
Moreover, older individuals marked at higher rates
than younger as reported in previous studies on
domestic dogs (Wirant & McGuire 2004; Wirant et al.
2007) as well as on wolves (Sillero-Zubiri & Macdon-
ald 1998) and coyotes (Gese & Ruff 1997). Actually,
adults dominated over subadult dogs and subadults
dominated over juveniles; males dominated over
females in each age classes (see Cafazzo et al. 2010).
Therefore, high-ranking adult males scent-marked
more frequently than other age/sex categories.
Raised-leg urination posture was exhibited by males
and rarely by females, which used mainly flexed-leg
urination posture. Our results suggest that different
postures might be correlated with certain behaviours
and contexts: flexed-leg urination appeared to be
associated with reproductive state and with the
defence of dens and food; raised-leg urination seems
to be mainly associated with aggression and demarca-
tion of territorial boundaries in both males and
females.
Influence of the context
In free-ranging dogs in India, a higher rate of scent
marking has been reported during the oestrus period
(Pal 2003). Although we observed females scent-
marking more often during oestrus, males scent-
marked mainly during feeding and in the absence of
sources of competition than in the presence of
receptive females. Agonistic interactions among
male dogs were more frequent in the presence of
receptive females than in the absence of sources of
competition and even more frequent in the presence
Table 7: We used the Wilcoxon signed-ranks test to compare the hourly rate of urine marking displayed by males (n =16) and by females (n =11)
and the hourly rate of ground scratching by all dogs (n =27) during agonistic and non-agonistic interactions with both other pack members and dogs
from other packs
Urine marking by males
(n =16)
Urine marking by
females (n =11)
Ground scratching
(n =27)
tzptzptzp
Agonistic interactions vs. non-agonistic interactions with other
pack members
0.00 3.52 0.0004 2.50 2.17 0.03 0.00 2.93 0.003
Agonistic interactions vs. non-agonistic interactions with dogs
from other packs
2.5 3.14 0.001 0.00 2.67 0.008 0.00 3.29 0.001
Ethology 118 (2012) 1–12 ©©2012 Blackwell Verlag GmbH 9
S. Cafazzo, E. Natoli & P. Valsecchi Scent-Marking Behaviour in Domestic Dogs
of food (see Cafazzo et al. 2010). Although scent
marking is linked to aggressive interactions and the
rate of aggressions was high in the presence of
receptive females, males marked more frequently in
the absence of sources of competition and in the
presence of food than in the presence of receptive
females. In the absence of sources of competition,
dogs marked mainly along territorial boundaries;
therefore, the use of scent marking during inter-
group competition for territorial defence might have
a predominant role with respect to the use of scent
marking during competition for receptive females.
As for males, we observed a higher level of competi-
tion among females in the presence of food than in
the absence of sources of competition (see Cafazzo
et al. 2010). The higher frequency of scent marking
by both males and females during feeding may be
linked to the high level of competition for food
among pack members. Moreover, dogs often marked
on food after taking their meals and before leaving
the feeding site, also when sufficient food still
remained there. According to Pal (2003), it may be
hypothesized that scent marking may facilitate relo-
cation of food resources, as also observed in red
foxes, wolves and coyotes (Henry 1977; Harrington
1981, 1982); although from our data, we cannot
exclude that dog scent marking during feeding in
order to guard this resources instead.
Scent marking by females during their oestrus likely
functions, at least in large part, as a declaration of
their reproductive state (Beach & Gilmore 1949;
Eisenberg & Kleiman 1972; Fox & Cohen 1977; Pal
2003); on the other hand, the lowest frequency of
marking behaviour displayed by males in the presence
of receptive females might suggest their scent marks
are not directly associated with the courtship of
females, in contrast to what reported by Pal (2003).
Nevertheless, we cannot exclude that females gain
information about the quality of potential mates from
the quality of their odours released by markings, as
observed in other species (Brown & Macdonald 1985;
Rich & Hurst 1998, 1999).
Conclusion
These results provide further support for the idea that
free-ranging dogs still retain some features of the
social organization and communication of their
wild ancestor, the wolf, that evolved before domesti-
cation (Bonanni et al. 2010a, b; Cafazzo et al. 2010;
Bonanni et al. 2011). They also remind us that many
of the proposed functions of marking behaviours are
not mutually exclusive, and all should be explored
through detailed field and laboratory studies of all
types of marks.
Acknowledgements
We are grateful to the caretakers, Annamaria Andre-
ozzi and Mirella De Paolis, for their availability to
answer all our questions about dogs and to Dr Gius-
eppe Cariola working at the Veterinary Hospital of
Rome for his help and assistance during the study.
Special thanks are due to Mark Bekoff for providing
relevant literature and to Roberto Bonanni who criti-
cally read the drafts of this paper and improved its
quality. Finally, we are thankful to the editor and the
referees whose suggestions improved the manuscript.
This research was partially funded by the Department
of Education, University and Research of Italian
Government (PRIN 2004 to P.V.), and by University
of Parma (FIL 2005 to P.V.).
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Scent-Marking Behaviour in Domestic Dogs S. Cafazzo, E. Natoli & P. Valsecchi
... Overmarking occurs with the same frequency in intact and castrated dogs [74], and high-status dogs investigate more urine marks than low-status dogs [73]. Overmarking female urine by males might happen to guard potential mates, and this might be enforced by aggressive encounters and domination display [75]. Overall, countermarking might just be a way of exchanging information [65], allowing individuals to assess competitors and to evaluate potential mates [73], but smaller dogs can exaggerate their signals and their competitive ability by using a higher leg raise during urination. ...
... Jezierski et al. identified that individual elements such as style and time of sniffing can influence the results of a dog's olfactory work [78]. Other factors such as the effects of the dog's routine, the use of cues other than olfactory ones (visual), and the non-verbal communication between handler and dog have also been mentioned [39,[71][72][73][74][75][76][77][78][79]. ...
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... Indeed, the domestic dog can transmit information to conspecifics relating to individual identity, including sex and social status. One method which dogs use to diffuse chemical signals is urine marking (Catala et al. 2019;McGuire Bemis 2017;Horowitz 2017;Cafazzo et al. 2012) as illustrated in figure 4. In female dogs, urine marking usually occurs around oestrus, indicating it is a signal related to mate attraction and sexual reproduction. However, urine marking in males, and also, to a lesser extent, females, is thought to be related to territory defence and dominance hierarchies (Cafazzo et al. 2012). ...
... One method which dogs use to diffuse chemical signals is urine marking (Catala et al. 2019;McGuire Bemis 2017;Horowitz 2017;Cafazzo et al. 2012) as illustrated in figure 4. In female dogs, urine marking usually occurs around oestrus, indicating it is a signal related to mate attraction and sexual reproduction. However, urine marking in males, and also, to a lesser extent, females, is thought to be related to territory defence and dominance hierarchies (Cafazzo et al. 2012). To illustrate using a personal anecdote; I lived for many years alongside an un-neutered male mixed-breed dog I had named Sebastian. ...
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Olfaction, as a semiotic modality, receives relatively less attention than other sensory modalities. However, chemiosemiosis and semiochemicals are fundamental components of zoosemiosis, occurring across animal taxonomic groups. Indeed, olfaction is thought to be one of the most ancient sensory modalities from an evolutionary perspective and significantly, even unicellular organisms, such as the bacterium Escherichia coli , utilize a form of chemiosemiosis when foraging for nutrients, as part of a process known as ‘chemotaxis’. Further, many taxonomic groups have evolved to produce dedicated ‘semiochemicals’ (often known as pheromones or allomones) which have the sole purpose of being diffused into the environment as a social signal. In this paper, I highlight the importance of Umwelt theory when studying animal communication, by reviewing the less conspicuous and intuitive chemiosemiotic modality, across animal taxa. I then go on to discuss chemiosemiosis within a linguistic framework and argue that complex pattern recognition underpins linguistic theory. Thus, I explore the concept that chemiosemiosis has features in common with language, when the factor of time, in the transmission and decoding of a signal, is taken into account. Moreover, I provide discursive evidence in support of a unified theory of sensory perception, based on structural and functional aspects of signal transmission and cognitive complex pattern recognition. I conclude by proposing a chemosemiotic hypothesis of language evolution.
... year-round territorial defence mainly by males (Gese & Ruff 1997;Pal 2003;Núñez & De Miguel 2004;Arnold et al. 2011;Cafazzo, Natoli & Valsecchi 2012) and male foxes guard their mates during the short oestrus period (Baker et al. 2004a;Kitchen et al. 2005a;Ralls et al. 2013), which may limit foraging opportunities (Alberts et al. 1996;Girard-Buttoz et al. 2014). In foxes, changes in group composition are promoted by population density and are accompanied by changes in mating system (Iossa et al. 2009), probably when males lose their ability to monopolise reproduction (Say et al. 1999;Wright et al. 2010). ...
... Philopatry can lead to increased competition for resources among kin (West et al. 2002;Lehmann, Perrin & Rousset 2006;Cafazzo et al. 2012 (Schneider & Kappeler 2014) and badgers (Cresswell et al. 1992) and also occurs in foxes (S Harris, unpublished data). In this study, the higher strength of dominant foxes meant they were more central in their social network; this may enable dominants to reinforce their social status and exert greater control over subordinate conspecifics to monopolise resources (Drews 1993;Modlmeier et al. 2014) and potentially reproduction. ...
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The red fox (Vulpes vulpes) is a contentious species of global importance as a predator, competitor, vector of disease and pest. Understanding their social system is essential for successful species management and mitigating human-wildlife conflict. Foxes are solitary foragers that form groups in certain circumstances. It is unclear whether these groups are beneficial or simply the ‘best of a bad job’ due to ecological constraints. Further, little is known about how stable or cohesive fox groups are, which can have implications for disturbance or removal. I addressed these issues to further our understanding of how fox groups operate. I set up camera traps in residential gardens where foxes were fed (food patches), to study social and competitive relationships in the high density fox population of suburban Bristol, UK. I collected over 152,000 photos of foxes and identified 192 individuals. Social groups were difficult to define, but the most reliable definition encompassed shared space use, a sighting threshold and the number of social connections. Group membership was relatively stable; foxes associated in communities, mainly within their territory boundary and maintained long term relationships that lasted until death or emigration. However, in all seasons the majority of relationships lasted less than a day and were probably between foxes from different social groups, indicating that intergroup contacts were not uncommon and occurred year round. Food patches were hotspots for sociality. Foxes improved their foraging efficiency by selecting high quality patches and coinciding their foraging activity with anticipated food availability, which increased contact rates at high quality patches. Females foraged according to their seasonal energetic demands, while males reduced their foraging effort in the winter mating season in favour of mate-searching behaviour. This contributed to a significant alteration in social structure in winter, with an increased rate of territory intrusion by strangers, a greater proportion of short term relationships and reduced social connectivity, demonstrating a role of females in maintaining group cohesion in winter. Dominant foxes occupied central network positions and therefore had a major influence on group connectedness; the demise of a dominant male led to significant social perturbation in one territory, supporting the importance of breeders in canid groups. Dominance also facilitated priority access to food, but so too did resident group membership, perhaps through familiarity with local resources and conspecifics. Subordinates compensated for intragroup competition by utilising lower quality patches and risky extraterritorial foraging, which was observed at an unexpectedly high rate year round. Contrary to the resource dispersion hypothesis, this indicated that group size was not limited by within-territory resources. To my knowledge, this is the most detailed study of fox sociality to date. Despite low contact rates fox groups were relatively stable and more similar in complexity to other canids than previously acknowledged. High individual flexibility in space use and year-round extraterritorial movement may have functioned to mitigate competition, but also explained how foxes responded so rapidly to local demographic change, providing evidence for the futility of management by removal.
... The dog's high sensitivity of the olfactory system might subserve a particular fitness-enhancing trait present in the evolutionary ancestor of today's canids, i.e. the detection of a prey in relative close proximity (Horowitz et al. 2013) or the inference about the location of a distal prey via airborne olfactory particles (Hepper and Wells 2005). Apart from that, domestic dogs use olfaction in social contexts, such as social interactions (Bräuer and Blasi 2021), identity recognition (Cafazzo et al. 2012;Lisberg and Snowdon 2009), intrasexual competition for mates, territorial defence (Bidder et al. 2020) and parental care (Foyer et al. 2016;Lévy et al. 2004). In general, the olfactory bulb and its projection structures, including the olfactory tract and striae, are larger in dogs than in humans in absolute terms and relative to brain size (Kavoi and Jameela 2011), suggesting higher olfactory functionality (Haehner et al. 2008). ...
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The extraordinary olfactory capabilities in detection and rescue dogs are well-known. However, the olfactory performance varies by breed and search environment (Jezierski et al. in Forensic Sci Int 237:112–118, 2014), as well as by the quantity of training (Horowitz et al. in Learn Motivation 44(4):207–217, 2013). While detection of an olfactory cue inherently demands a judgment regarding the presence or absence of a cue at a given location, olfactory discrimination requires an assessment of quantity, a task demanding more attention and, hence, decreasing reliability as an informational source (Horowitz et al. 2013). This study aims at gaining more clarity on detection and discrimination of olfactory cues in untrained dogs and in a variety of dog breeds. Using a two-alternative forced choice (2AFC) paradigm, we assessed olfactory detection scores by presenting a varied quantity of food reward under one or the other hidden cup, and discrimination scores by presenting two varied quantities of food reward under both hidden cups. We found relatively reliable detection performances across all breeds and limited discrimination abilities, modulated by breed. We discuss our findings in relation to the cognitive demands imposed by the tasks and the cephalic index of the dog breeds.
... For example, a dog has a highly developed olfactory sense. As a form of signaling, dogs can obtain information about another individual, including sex, age, and reproductive status, from its scent (Cafazzo et al., 2012). It is therefore pertinent that all efforts to detect linguistic features such as grammar and syntax in animal communications have misguidedly focused on vocalization and ignored other modalities. ...
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In this paper, I examine the way humans interact with domestic companion animals, with a focus on 'positive reward-based training' methods, particularly for dogs. From a biosemiotic perspective, I discuss the role of animal training in today's society and examine what binary reward-based reinforcement schedules communicate, semiotically. I also examine the extent to which reward-based training methods promote better welfare, when compared to the more traditional methods which rely on aversive stimuli and punishment, if and when they are relied upon excessively. I conclude that when used as the primary means of communication, they have the potential to be detrimental to animal welfare, because the underlying social signal is control and resource dominance. As an alternative view to behaviourist-based learning theory and conditioning, I outline how enactivist theories of cognition support a semiotic approach to interspecific human-animal communication. I therefore propose a move toward a dynamic semiosis and mutual understanding based upon Peirce's phenomenology, resulting in a more balanced merging of Umwelten. The aim is to create rich and more complex semiospheres around humans and domestic animals, which allow for individual agency and autonomy.
... The fact that dogs with higher levels of exploration had more intensive forays might indicate that attachment in those dogs is not strong. Further, exploration behaviours might be exhibited in a more original, non-domestic context, i.e., search for resources or marking territory (Cafazzo et al., 2012;Dos Santos et al., 2018). Although the SSP is a widely used assessment to study attachment in dogs, future research on free-ranging dogs also might consider alternative approaches, such as manipulative tasks in the presence or absence of caregivers (Horn et al., 2013) or shifting the experimental setting to the caregiver's homes (Wedl et al., 2010). ...
Article
Domestic dogs have a close and mutualistic relationship with humans. When unconfined, they usually stay close to the owner’s home, but some undertake intensive forays in nature with negative impacts on wildlife. Predictors for such problematic dogs in previous research concentrated on dog characteristics and husbandry. Here we additionally explored which aspects of the dog-human bond influenced the movements of free-ranging village dogs in southern Chile. Using an interdisciplinary framework, we assessed the strength of this relationship through (i) attachment behaviours performed during the Strange Situation Procedure (SSP, dog’s perception of the relationship) and (ii) the Monash Dog-Owner Relationship Scale questionnaire (MDORS, owner’s perception) in 41 dog-owner dyads while remotely monitoring the dogs’ movements using GPS tracking (n = 36394 locations). We found that 39% of dogs had > 5% of their locations in natural areas, but only three individuals exhibited overnight excursions. Home range size (1.8 – 4227 ha) and mean distances to the owner’s home (0 – 28.4 km) varied greatly among individuals. Through generalized linear models we identified that dogs had larger home ranges, moved farther away from home or accessed nature more (i.e., they exhibited more intensive forays) when they explored more, greeted their owners intensively, and expressed more passive behaviours in the presence of their owners (SSP). However, the MDORS questionnaire was a poor predictor of home range, distance to home and access to nature. When considering the dogs’ background, older dogs, males, and dogs that got missing more frequently exhibited more intensive forays. Compared to SSP results in confined dogs, we suggest that owners of free-ranging dogs do not play an important role as an attachment figure. We conclude that the dog-owner bond indeed influences roaming behaviour in dogs. This highlights the necessity of wildlife management strategies considering the cultural context. In specific terms, we recommend to foster the knowledge of the importance of bonds between dogs and their owners in educational campaigns on responsible dog ownership, along with biological (age, sex) and behavioural characteristics (exploration, getting missing). That way, awareness campaigns can focus on owners of possible problematic dogs.
... According to the thermoregulatory behaviour, most of the time, tigers lying down [45%] and 19% of tigers facing direct sunlight and 20% of tigers observed in the shade [49]. Defecation does not play a crucial role in olfactory contact for free-range dogs, and standing and squat postures are consistent with natural excretion [50]. Lynx preferred conspicuous objects for marking and increased scent marking rate when walking along with linear structures, such as forest roads [51][52][53]. ...
Article
Wildlife forensic is the implementation of the combined sciences, natural and cultural science. The court of law focused on the regulation of wildlife protection and conservation. Criminals that regulate illicit trade across nations and continents face the most significant threat. The tiger is the largest of all cats, the most iconic, and one of the most endangered. Due to its higher trading value, those animals are unlawfully slaughtered or poached for black-marketing, medical use and jewellery products. Tiger or leopard protection indirectly protects habitats and ecological health. By transmitting signals through vision, scent marks and voices, they are socially connected. Because of the dramatic reduction in tiger numbers, studying their behaviour habits is very difficult. Therefore, in this study, the Indian Leopard and Bengal Tigers [Felidae-family] are studied using the non-destructive approach through its claw nail markings. The transactional survey was the approach adopted for collecting data-signs of tiger nail bruises. This review focuses on the study of their behavioural habits and extensively study them for their conservation.
... In FRDs, the fitness consequences of grouping have not been investigated yet, although it has been suggested that one of the most important benefits of grouping may be the possibility of defending resources collectively Carr 1995, Bonanni and. In the study population, individuals displayed scentmarking behavior typical of wolves (which was not restricted to the highest-ranking male and female, although its rate was positively affected by dominance rank; Cafazzo et al. 2012), and larger packs usually outcompeted smaller ones in interpack conflicts over food and space (Bonanni et al. 2011). Moreover, cooperation in raising puppies, which has been observed primarily among closely related females, may provide them with inclusive fitness benefits (Paul and Bhadra 2018). ...
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Domestication has greatly changed the social and reproductive behavior of dogs relative to that of wild members of the genus Canis, which typically exhibit social monogamy and extended parental care. Unlike a typical gray wolf pack that consists of a single breeding pair and their offspring from multiple seasons, a group of free-ranging dogs (FRDs) can include multiple breeding individuals of both sexes. To understand the consequences of this shift in reproductive behavior, we reconstructed the genetic pedigree of an FRD population and assessed the kinship patterns in social groups, based on genome-wide single-nucleotide polymorphism genotypes. Consistent with behavioral observations, the mating system of the study population was characterized by polygynandry. Instead of the discreet family units observed in wolves, FRDs were linked by a network of kinship relationships that spread across packs. However, we also observed reproduction of the same male–female pairs in multiple seasons, retention of adult offspring in natal packs, and dispersal between neighboring packs—patterns in common with wolves. Although monogamy is the predominant mating system in wolves, polygyny and polyandry are occasionally observed in response to increased food availability. Thus, polygynandry of domestic dogs was likely influenced by the shift in ecological niche from an apex predator to a human commensal.
... In the last 30 years there has been a growing scientific interest in dog cognition as dogs have developed special skills to function effectively in the human environment, as a consequence of the oldest domestication process we have evidence for 1 . It is well known that dogs have an excellent olfactory sense, and that they rely heavily on it when exploring the environment or recognizing individuals [2][3][4][5][6] . Dogs can learn to recognize various odours 7,8 , they can be trained to discriminate and indicate the presence of odours of narcotics, explosives, plants, parasites and various diseases such as cancer and diabetes [9][10][11][12][13][14][15] . ...
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Most current knowledge about dogs’ understanding of, and reacting to, their environment is limited to the visual or auditory modality, but it remains unclear how olfaction and cognition are linked together. Here we investigate how domestic dogs search for their owners using their excellent olfactory sense. We raise the question whether dogs have a representation of someone when they smell their track. The question is what they expect when they follow a trail or whether they perceive an odour as a relevant or non-relevant stimulus. We adopted a classical violation-of-expectation paradigm—and as targets we used two persons that were both important to the dog, usually the owners. In the critical condition subjects could track the odour trail of one target, but at the end of the trail they find another target. Dogs showed an increased activity when the person did not correspond with the trail compared to a control condition. Moreover, we found huge individual differences in searching behaviour supporting the assumption that dogs are only able to smell when they really sniff, and that the temperature has an influence on dogs performance. Results are discussed in the light of how cognitive abilities, motivation and odour perception influence each other.
Chapter
Dogs, together with humans, are one of the most successful species on the planet. In the Western world, dogs usually live as companions and often take on important roles for their human partners. However, a larger proportion of dogs worldwide are free-ranging – living in the human environment, but otherwise making their own decisions. In this chapter we summarize the various aspects of the socio-ecology of these dogs. The discordant reports, going from solitary to structured packs, likely reflect the flexibility and adaptability of this species as well as possible genetic differences between populations of FRDs. The high variation in sociality begs the question of which socio-ecological factors, such as food distribution and abundance, interdependence, closeness to humans, etc., may be affecting the dogs’ social structure. Where packs do form, the internal structure remains still scarcely understood. It appears that, in most cases, groups are composed of multiple males and females, but mostly due to the absence of genetic data and/or long-term studies, it remains unclear whether the pack members are related with each other or not. Both males and females are largely promiscuous, and parental care seems to be mostly provided by the mother, with varying support from putative fathers and other (related?) females. Dog packs collectively defend established territories, marking and engaging in defensive aggression against other packs.
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The mating strategies of male mammals consist of intrasexual competition for access to females and then attempts to maximise contacts with receptive females. The form that these attempts take is strongly influenced by female movements in response to food and their tendency to form social groups. Female reproductive success (RS) is primarily (although not entirely) determined by the number of offspring that can be produced and the factors that limit this are the availability of the nutrients needed for reproduction and the chance that offspring will be killed by predators. Many aspects of female behaviour are profoundly influenced by these considerations: for example, the movements of female antelopes in relation to spatial and temporal variation in grassland quality appear to be adaptations to optimise food quality while avoiding habitats that offer cover to predators. In addition, females can reduce the chance of predation by cryptic behaviour, alone or in small groups, or by the “selfish herd” advantages of joining larger social groups. Collectively, these female behaviours appear to dictate the mating strategy that is most profitable for males to adopt (Gosling, in press). Excluding lekking, these strategies fall into two main classes: (1) males follow one or more females, waiting until they become receptive, and (2) they defend part of the food resource that females need so that they can intercept females that are attracted to the resource (Gosling, in press). This second strategy is known as “resource defence territoriality” (Emlen and Oring, 1977).
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Urine-marking by Canis lupus never occurred when a cache was stocked, rarely occurred during later investigation if some food was still present, but usually occurred soon after the cache was emptied. The animal marking an empty cache was often not the one which had exploited it. Once an empty cache was marked it received little further attention, as opposed to caches that were empty but not urine-marked. Urine-marking may thus enhance foraging efficiency in wolves by signalling that a site contains no more edible food despite the presence of lingering food odors.-from Author