Full text of DOI:10.1007/BF03192451

FRAGMENTA THERIOLOGICA
Acta Theriologica 46 (4): 441–445, 2001.
PL ISSN 0001–7051
Behavioural observations of interactions in a free-ranging
lynx Lynx lynx family at kills
Paolo MOLINARI and Anja MOLINARI-JOBIN
Molinari P. and Molinari-Jobin A. 2001. Behavioural observations of interactions in a
free-ranging lynx Lynx lynx family at kills. Acta Theriologica 46: 441–445.
The behaviour of a free-ranging female lynx Lynx lynx Linnaeus, 1758 and her
kittens at 12 different kills was studied for 44 hours of observation from September
1996 to March 1997. The development of interactions at kills of a lynx family group
showed the following pattern: until the end of September we often observed two lynx,
usually both kittens, feed from the kill at the same time. After the age of four months
aggression between kittens was observed frequently, with the bigger kitten being
dominant. From September the kittens were never again seen feeding together at the
kill. However, we never observed fighting, and aggressive behaviour did not increase
with the age of the kittens. Whereas until December one of the kittens was always first
at the kill, from January onwards it was mostly the adult female who ate first. She
introduced her kittens to the home range of a neighbouring female where the family
break-up occurred. The kittens were last seen together with their mother on 26 March.
Dispersal seemed to be initiated by the female abandoning the kittens.
Progetto Lince Italia, Via A Diaz 90, 33018 Tarvisio, Italy,
e-mail: p.molinari@progetto-lince-italia.it (PM); University of Bern, Baltzerstrasse 3,
3012 Bern, Switzerland, e-mail: JobinMolinari@aol.com (AMJ)
Key words: Lynx lynx, behaviour, kill use, dispersal
Introduction
Adult European lynx Lynx lynx Linnaeus, 1758 live as solitary individuals with
exclusive home ranges. The male does not take part in parental care (Breitenmoser
et al. 1993). At the end of May, the female bears litters of one to exceptionally four
cubs in a breeding den where they are maintained for approximately 6–9 weeks. In
August, when meat becomes an important part of kitten’s diet, the young lynx
accompany the mother to the kill (Schmidt 1998). Lynx kittens stay with their
mother until they are 10–11 months old. The family break up coincides with the
lynx’s mating season in February–March (Schmidt et al. 1997, Zimmermann 1998).
Most descriptions of direct observations in feeding order of a lynx family group
were based on data from enclosures (eg Naidenko 1998). Direct observations of lynx
in the wild are rare and they seldom last for more than few minutes. We had the
unique opportunity to observe an adult female lynx with her two kittens at kills in
the wild from September 1996 to March 1997. This paper describes the develop-
ment of interactions at kills until the family break up.
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Material and methods
The study was conducted in the Jura Mountains, a secondary chain of limestone mountains
forming the north-western border of Switzerland with France. The most important prey species for
lynx in the Jura Mountains were roe deer Capreolus capreolus (69%) and chamois Rupicapra rupicapra
(22%; Jobin et al. 2000). Lynx usually fed for several days on an ungulate kill.
In December 1990, the adult female lynx “Aida” was caught in the Swiss Jura Mountains with
foot-snares installed at a fresh kill and fitted with a radio-collar (Breitenmoser et al. 1993). Until 31
December 1995, she was located on average every 2.8 days. During these 5 years she was re-captured
twice with foot-snares and four of her kittens were caught with the same system, which proved to be
very efficient. However, when Aida had to be caught the fourth time in order to change the radio-collar
in the winter of 1995/96, we were not able to catch her with the snares, as she became trap-wise. We
therefore had to change the capture technique: when we found a fresh kill made by her, we put up a
tent 4–8 m from the kill and waited inside with a blowpipe for Aida to come to feed. Aida was
re-captured with the blowpipe method on 16 February 1997.
The observer in the tent recorded the feeding succession and aggressive interactions of the
different lynx. To be able to observe the lynx after dusk we installed a small torch above the kill. The
signal from Aida’s radio-collar allowed us to estimate her distance to the kill even when we were not
able to see her. We continued our observations until family break-up with the same method even after
the capture of Aida.
Results
In May 1996, Aida gave birth to three kittens: two males and one female. From
September 1996 to March 1997 we observed Aida and two of her kittens at 12
different kills for 44 hours. One of the two kittens was clearly bigger than the other;
the third kitten presumably died before September. We started the observations on
14 September. Both kittens arrived at the same time. They spent a total of 85 min
on the kill, of which 45 min together, they did not seem to eat a lot of meat. From
the radio-signal we knew that Aida was nearby, but she only came to eat when her
kittens had apparently lost interest. The next day, both kittens arrived before Aida
and fed together at the kill. After a pause of two hours they restarted feeding, this
time, however, not together but alternating, with the smaller kitten feeding longer
than the bigger one. One hour later – when the kittens had finished feeding – Aida
arrived. While she fed, the bigger kitten played around with the kill. As soon as Aida
finished, both kittens restarted feeding before they all left. This detailed
description shows the typical feeding behaviour and rank order in which the lynx
fed (Table 1). On 26 September it was the bigger kitten which fed first, followed by
the smaller one. While the smaller one fed, the other kitten snarled and showed his
teeth. The smaller kitten retreated immediately. On 1 November we observed an
interaction between Aida and the bigger kitten: before it approached the kill Aida
was eating at, it rubbed against her, then they faced each other pushing their heads
together. It was only afterwards that it started to feed. We also observed how the
smaller kitten tried to feed while the bigger one was on the kill. However, the bigger
kitten no longer tolerated the smaller one nearby. The smaller kitten had only
access to the kill when the bigger one had finished feeding.

Observations of a lynx family at kills
443
Table 1. Development of feeding order in a free-ranging lynx family from 14 September until family
break-up in March. K1 – bigger kitten, K2 – smaller kitten, Aida – adult female, K1-K2 – both kittens
together, Aida-K1 – female and bigger kitten together. The time one or more lynx were observed at the
kill is given in hours and minutes.
Date
Time at kill
Feeding order
K1, K2, K1-K2, Aida
14 September
15 September
26 September
1 November
28 November
6 December
7 January
04.50
05.40
03.20
02.25
04.40
01.40
02.30
02.25
03.15
00.40
04.05
03.10
04.40
K1-K2, K2, K1, K2, K1, K1-K2, Aida, Aida-K1, K1-K2
K1, K2, K1, K2, Aida
Aida, Aida-K1, K1, K2, K1, K2
K1, K2, K1, K2, Aida
K1, K2
Aida, K1, K2, Aida
K2, K1, Aida, K2
23 January
31 January
4 February
16 February
10 March
Aida, K2, K1, K2
Aida
Aida, K2, K1
Aida, K2, K1, K2, K1
Aida, K2
18 March
From 7 to 22 November we found four foxes and one hare killed and eaten by
Aida, but no sign of the kittens. But on 28 November we found an ungulate kill
where the whole family was together again. At this kill we observed a similar
pattern as previously: the bigger kitten ate first; but as soon as the small one
approached, it was chased off; Aida fed last. On the kill found on 6 December only
the two kittens were observed (Table 1). The next day we found another kill nearby
that Aida presumably used while the kittens fed on the old kill.
By the end of January 1997, Aida started to make excursions with the kittens
out of her usual home range. She first travelled north-eastwards along the edge of
the neighbouring female’s home range, where we found a roe deer fawn killed, but
already completely consumed (28 January). The next kill on 31 January was even
further away from her home range. Aida fed first and when the small kitten tried to
approach, she chased it off. And as soon as the smaller one tried to feed it was
chased off by the bigger one. When this kill was finished the lynx family headed
south-westward and turned back to their usual home range, where we observed
Aida alone on a roe deer doe kill. She then traversed her home range quickly, still
heading south-westwards into the former home range of the female “Elsa”, who
had been poached 5 months previously. Aida and her kittens were to stay in the
former home range of Elsa until the family break-up. On the following kills Aida
always fed first, the kittens only came near the kill when Aida had left. On 10
March we observed the family for the last time together at the same kill. On 18
March Aida again ate first; afterwards the small kitten fed, called several times
without receiving an answer, and then left as well. The kill was then abandoned

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P. Molinari and A. Molinari-Jobin
and we had no indication that the big kitten had fed on this kill. On 26 March we
observed tracks of Aida and the two kittens travelling further south-westward. On
1 April Aida was back in her usual home range – alone.
Discussion
We described the development of interactions at kills of a lynx family group in
the Jura Mountains. While until December one of the kittens was usually first at
the kill, from January onwards it was mostly the adult female Aida who ate first.
The hierarchy changed when the kittens were around 7 months old. An apparent
feeding order with the largest lynx eating first and the smallest last was also
observed at a kill found at the end of December (Literak et al. 2000).
Sokolov and coauthors (1994) observed fights between sibling kittens 6–9 weeks
old that led to significant traumas and sometimes to death. When we started our
observations, kittens were already 17 weeks old, and aggressive interactions
observed were always followed by immediate retreat of the recipient. In fact, the
older the kittens were, the more the family members tended to avoid one another
and to show increasing independence just before the time of dispersal. According to
Schmidt (1998) there is no gradual loosening of contact between the mother and
her kittens towards the end of the raising period: kittens leave their mothers
suddenly, without an initial phase of separation. However, as early as November
kittens were observed to spend time away from the mother, when Aida might have
reinforced her hunting effort to make parallel kills to ensure constant access to food
for her kittens, where the kittens were using the old kill and Aida the new one.
The majority of the literature on juvenile dispersal assumes or presumes that
resource and/or reproductive competition occur between adults and juveniles and
thus juvenile dispersal is forced by resident adults of the same sex. However, Wolff
(1993) pointed out that very few mammal studies have documented that juvenile
dispersal results from adult aggression. According to our observations, lynx
dispersal seemed to be initiated by the female abandoning the kittens. The only
aggressive behaviour of Aida towards a kitten at a kill was observed two months
before separation. In cougars Felis concolor, Beier (1995) did not observe aggres-
sion of the female towards the kittens either: the mother often left her kitten(s) 0–3
km at the edge of her home range while she moved to the opposite edge of her home
range.
In the Jura Mountains, most separations of lynx kittens from their mothers
occurred within the home range of the mother, where the kittens stayed for 31 25
days after separation (Zimmermann 1998). Aida’s excursions beginning at the end
of January may be explained by resource competition: as Aida already competed
with her daughter of the previous year who took over her core area (Swiss Lynx
Project, unpubl.), she introduced her kittens into an area where, presumably, no
female was present. This example showed that dispersal might be influenced by a

Observations of a lynx family at kills
445
variety of social and environmental conditions. In conclusion, we suggest that
dispersal in lynx is not caused by female parent aggression.
Acknowledgements: We thank F. Zimmermann for support with the fieldwork, and S. Lovari,
C. Breitenmoser-Würsten and three unknown referees for comments on an earlier version of the
manuscript. The study was funded by the Federal Office of Environment, Forestry and Landscape
(BUWAL), the canton of Vaud, the Swiss League for Protection of Nature (Pro Natura), and WWF
Switzerland.
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Received 2 March 2001, accepted 2 August 2001.