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Culpeo Zorro (Andean Fox) - Lycalopex culpaeus
Culpeo Zorro (Andean Fox) - Lycalopex culpaeus

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Kingdom: Animalia 
Phylum: Chordata 
Class: Mammalia 
Order: Carnivora 
Family: Canidae 
Genus: Lycalopex 
Species: culpaeus

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Range and Habitat

The culpeo ranges along the entire length of western South America. It is found in Ecuador, Peru, Bolivia, Argentina and Chile, with a small population in Columbia. The culpeo is more numerous in the southern parts of Argentina, with a strong population of over 200,000 individual animals. In northern Argentina, however, the culpeo is almost nonexistent. They prefer the pampas grasslands and deciduous forests of their range.

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Physical Appearance

The culpeo is the largest of the South American foxes. Their overall size increases the further south in their range they live. Males are 10 - 15% larger than the females. Their coat is brownish-tawny colored, with paler undersides, and a generally greyish back, and their tail has a black tip.

Shoulder Height:

Head and Body Length:
24-46 in. (60-115 cm) 
Tail Length:
12-18 in. (30-45 cm) 
11-29 lb. (5-13.5 kg)


Rodents and lagomorphs (rabbits and hares) are the most prominent in the culpeo's diet. They sometimes take young lambs a week old and younger. They are the main form of control of the rabbit population that was introduced to South America in the early 1900's. Depending on where they live, their diet can be almost 97% carnivorous to some areas where up to 30% of their diet is vegetable matter.

Reproduction and Life Cycle
The mating period is from August to October. After a gestation period of 55-60 days, the female gives birth to 2-5 cubs in a den among the rocks. The father stays to help gather food for the nursing mother. The pups are a sandy color. When they are only a week old, they are already fighting to establish a hierarchy. The pups reach adulthood by autumn, at which point the males leave to establish their own territories, while the females stay with their parents. Their life expectancy, for some reason, is very short. Of 100 foxes studied in Chile, only five were older than 2 years.

Life information
Gestation: 55-60 days 
Litter size: 2-5 
Age at sexual maturity: 
Male: less than 1 year 
Female: less than 1 year 
Life Span: 2-3 years

Social Behavior
The culpeo society is a hierarchical matriarchy, since it is the females who fight for dominance. The dominant females inherit their territory from their parents, while the males have to search for their own territory. The dominant female in each territory has breeding rights, and subservient females must leave to establish their own territory to breed. The dominant female also feeds first. Courtship, which occurs during the winter, involved a lengthy ritual of mock-fighting.

The culpeo is hunted for its skins in Argentina and Bolivia, but this does not seem to be having an impact on their population.

Lycalopex culpaeus andinus (Thomas, 1914) 
Lycalopex culpaeus culpaeus (Molina, 1782) 
Lycalopex culpaeus lycoides (Philippi, 1896) 
Lycalopex culpaeus magellanicus (Gray, 1837) 
Lycalopex culpaeus reissii (Hilzheimer, 1906) 
Lycalopex culpaeus smithersi (Thomas, 1914) 

Print References
Alderton, David. Foxes, Wolves, and Wild Dogs of the World. Blandford Press: United Kingdom, 1994. 
Nowak, Ronald. Walker’s Carnivores of the World. The Johns Hopkins University Press: Baltimore, 2005.
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South American fox confronts prey eight times its size

Jeremy Hance 
February 10, 2009

In a paper in Mammalia researchers from the Wildlife Conservation Society (WCS) announce the first observation of South America’s culpeo fox hunting young guanacos, a relative of llamas. In doing so the fox comes head-to-head with aggressive mothers defending their young: researchers were surprised to find the small 30 pound (14 kg) predator facing off a group of 260 pound (120 kg) adult guanacos. 

The hunt provided new information not only about the diet—and audacity—of the culpeo fox, but also showed never-before-seen behavior from the guanaco. When attacked by the culpeo fox, researchers were surprised to see the guanacos move into defensive herds and not shy away from kicking and charging at the fox. Before this, guanacos were thought to have only one strategy against predation—flight. Whenever a guanaco is attacked by a puma, its other known predator, it flees rather than defends itself. 

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The culpeo fox chasing a guanaco. 

While the puma attacks guanacos with stealth and ambush, the culpeo fox chases young guanaco until they drop from exhaustion, a hunting strategy known as “cursorial predation”. The guanaco’s novel defensive response to the culpeo fox is probably due both to the fox’s smaller size and its hunting strategy, which makes flight a useless response. 

As opportunistic predators, culpeo fox have been known to prey on lizards, rabbits, birds, rodents, and even sheep. But successfully hunting young guanaco—and surviving attacks from adults—awards this small wild canine new stature. 

The observations were made on the island of Tierra del Fuego off the southern tip of South America. Perhaps significantly the island is free of pumas. 

CITATION: Andres J. Novaro, Claudio A. Moraga, Cristobal Bricen, Martin C. Funes, Andrea Marino(2009) First records of culpeo (Lycalopex culpaeus) attacks and cooperative defense by guanacos (Lama guanicoe). Mammalia, Volume 73.
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  • Claudiu Constantin Nicolaescu
Diet of the andean fox Lycalopex culpaeus (Molina 1782) in a dry inter-Andean forest in northern Ecuador

We describe the diet of the Andean fox (Lycalopex culpaeus) based on the analysis of 36 feces collected in the dry forest on San Antonio, Pichincha province, Ecuador. We found 94 prey items that were grouped into five categories: arthropods, mammals, birds, vegetables and miscellaneous (fungi and plastic remains). Mammals were the most common food item in terms of abundance and frequency; among them, the forest rabbit Sylvilags andinus was the most important prey.

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Feeding ecology of the culpeo in southern Ecuador: wild ungulates being the main prey.

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We identified a total of 413 prey items in 304 scats 
(Tab. 1), collected during a year of sampling. A total of 16 mammalian species were identified, which were by far the most consumed prey. Indeed, mammals were 
present in 100% of the scats analysed. Cervids were the most consumed prey group, with a frequency of occurrence (FO) of 71%. The next most significant group in terms of FO was small mammals (26%), followed by big rodents (12%), carnivorous (10%) and rabbits (8%) (Tab. 1). Birds and fruits were poorly represented, both being found in only 3% of the scats analysed. Contributions of consumed biomass in terms of percentage were similar, except for small mammals (0.95% CB), others (0.11% CB) and fruits (0.02% CB), with values much lower than those provided by FO.

hair remains of puma were found in scats collected during different samplings and times, thus belonging to three different individuals. In fact, puma remains were also found in the culpeo’s diet elsewhere (see Pia, 2013). There are two possible explanations for this finding: one, pumas were consumed as carrion (the most probable if these individuals were adults); and two, there was active predation on young pumas. In support of the latter it is known that coyotes kill adult bobcats (see Palomares and Caro, 1999), whose sizes could be similar in some cases to those of adult culpeos (especially males) and young pumas (especially females). Because these felids can kill 
culpeos (Pacheco et al., 2004; De Oliveira and Pereira, 
2014), young pumas could be killed in turn by adult 
culpeos if given the opportunity, as a culpeo’s strategy for reducing the risk of intra-guild predation (e.g. Palo-
mares and Caro, 1999). However, having only the evi-
dence of hair remains in scats we were unable to differentiate between the two possibilities.

Composition of the diet of Lycalopex culpaeus in an inter-Andean dry forest in San Antonio de Pichincha,
North of Ecuador, based on 36 fecas collected in 2015 and 2016.

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Fox culpeo fueguino - lycalopex culpaeus lycoides

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Scientific classification
Kingdom: Animalia 
Phylum: Chordata 
Class: Mammalia 
Order: Carnivora 
Family: Canidae 
Genus: Lycalopex 
Species: culpaeus

Description: This is the largest and heaviest subspecies of all those that make up the species Lycalopex culpaeus. Some males reach 156 cm of body length, being in this measure the length of the tail 53 cm and weigh up to 14 kg, being the second largest canid in South America.
Its fur is also denser and longer than that of the other subspecies, which is why it is widely used in fur, where it is treated as a species of its own: Tierra del Fuego fox. This subspecies has the appearance of a sturdy fox, reddish head and legs, belly, neck and mouth white and gray back striped black. The tail is very populated with gray hairs that turn black at its tip.

Distribution: It is distributed in the archipelago of Tierra del Fuego, at the southern end of the American continent, being the southernmost canid in the world. It lives in all the habitats of the Big Island of Tierra del Fuego and on Hoste Island. It was extirpated in the historical times of Gable Island. Although it has favorable habitat for this subspecies, it is not present in Navarino Island or in other austral islands, which could not be reached because they were separated from their populations by the cold and deep channels of the Pacific.

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Diet: It feeds on rodents, rabbits, birds and lizards, and to a lesser extent on plants and carrion.
Solo attacks were observed on the Tierra del Fuego fox (which has respectable body dimensions) to hunt young and even subadults of guanacos, with a disparity between predator and prey of 14 kg and up to 40 kg in the young guanaco. This behavior was unknown until 2007 when it began to be observed in the Karukinka natural park, on the Big Island of Tierra del Fuego. Scientists stipulate the reason for the alleged new depredation because of the adverse climatic condition of the island, which makes food scarce and weakens the animals. The absence of pumas on that island is also considered as a factor, which allows the fox to occupy its ecological niche. Finally, it is presumed that this behavior is not new, since the fox is nocturnal, a habit that allows it to collect most of its prey, but makes observation difficult. Faced with the threat of the red fox, the guanacos resort to cooperative strategies to protect their young, developing a shield formation, a circle around the vulnerable. If successful, they can kick the canine away, something that is impossible to do in front of a puma.
In some very anthropized areas it attacks flocks of sheep, which is why it has been harshly persecuted by farmers, who shoot or poison carrion. As a consequence of this, it has become very rare in some areas and in others it has become extinct.


Content of feces of lycalopex culpaeus obtained in Magallanes on August 2-3 (winter) and November 21 -30 (spring) of 1978.

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One of my favorite Canines of all time. I would love to see what big prey they rarely take, since I have heard it can be pretty big.
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Agonistic behavior between introduced beaver (Castor canadensis) and endemic culpeo fox (Pseudalopex culpaeus lycoides) in Tierra del Fuego Island and implications

Over the last 70 years, introduced beavers (astor
canadensis) have been successful in establishing and modifying the landscape of southernmost Patagonia. Habitat availability and lack of large carnivorous predators have contributed to this success. The Fuegian culpeo fox (Pseudalopex culpaeus lycoides) is an endangered subspecies and the largest native predator found in Tierra del Fuego Island. The predatory behavior of a culpeo towards a beaver was studied by analyzing a video footage recovered by tourists, and consumption of beaver was documented with camera traps. An ethogram of the predatory behavior sequence was developed and true durations and percentage of time allocated to each behavior were analyzed. The Bcapture^ and Bwatch^ behaviors had the highest durations within the predatory sequence (61.83 and 42.61 s, respectively), while Brest^ was the most frequent maintenance behavior observed (93.82 s). The culpeo may provide the only natural population control for beavers, although up to date, there is no evidence to confirm this ecological role. Based upon photos from camera traps, we confirm the occurrence of fox feeding on beavers. This is the first description of the stages of the interaction between a Fuegian culpeo fox and a North American beaver under natural conditions. We discuss the ecological implications of this interaction.


After the first revision of the video footage, the constructed ethogram included four behaviors associated to the predatory behavior sequence of the culpeo and two maintenance behaviors described in Table 1. True durations (seconds) and percentage of time allocated to each behavior are presented in Table 2.From the predatory sequence, Bcapture^ comprised the highest percentage of time followed by Bwatch^ while, within the maintenance behaviors, Brest^ had the highest duration.
The sequence analysis and true durations of the behaviors involved in the predatory behavior are presented in Fig. 1. From the four behaviors, Bcapture^ and Bwatch^ involved the highest amount of time of the sequence.
The beaver was observed to deploy two behaviors during the footage. These were Bgalloping^ on dry land (locomotor behavior) and Bseeking protection in water^ (protection behavior).
Additionally, images retrieved from camera traps show culpeo consuming beaver’s carcasses. In Fig. 2, a group of Fuegian culpeos (potentially a female and two offspring) is observed at night ingesting beaver meat from a specimen that was caught by a trap. In the second image (Fig. 3), and adult culpeo fox is observed scavenging on a trapped beaver carcass
during the day. These photographs are provided to demonstrate that foxes can and will eat beaver's meat when provided the opportunity.

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The present manuscript describes for the first time an agonistic interaction between a Fuegian fox and a beaver, involving a predatory sequence with no predation. This interaction occurred during the southern winter; when food is scarce and  thus, it may represent an opportunistic event on which the fox
sought resources during the cold season.
MacNulty et al. (2007) established an ethogram for carnivore predatory behavior based upon wolves (Canis lupus). We were able to identify in the fox four of the six behavioral components proposed by MacNulty et al. (2007) (Table 1 and Fig. 1). The behavior Bsearch^ may not have been identified in the 
culpeo due to the opportunistic nature of the film, so we cannot conclude it is not present. The Battack group^ component is not present because only one beaver was observed. The fox spent most of its time resting after the beaver escaped, which occurs 
towards the end of the footage after the failed attack (35%; Table 2). During the last seconds, the fox pants intensely, probably due to fatigue as result of the predatory behavior displayed.
One key aspect to the outcome of the observed footage is the presence of a creek where the beaver can seek refuge. 
Beavers are known to remain close to watercourses as means of security. In addition, due to their size (up to 45 kg), beavers are known to be strong enough to drown a dog or a wolf, by pulling them underwater (Gorbunova et al. 2008). The beaver displayed two behaviors associated with protection against 
predation: Bgalloping^ and Bseeking of protection in the water.^ According to Patenaude (1984), seeking protection in water is a reaction to disturbance that appears at the age of 6–10 days in beavers. Galloping behavior has also been described as an escape reaction on dry land (Patenaude 1984). The beaver’s behavioral reactions were successful in this case, likely due to the presence of a nearby stream.


Culpeos are known to display predatory behavior towards juvenile guanacos (Novaro et al. 2009) and attack huemul deer (Hippocamelus bisulcus), both fawns (Corti et al. 2010) and sick adults (Briceño et al. 2013); all of which are heavier than culpeos. Based upon the behaviors to wards a beaver analyzed in this study, we conclude that culpeos can also deploy predatory behavior towards beavers, even including them in their diet when possible.
Whether this predatory interaction results in actual predation will probably depend on age and health status of beaver attacked and on proximity to streams where beavers can seek refuge[b].[/b]


The Fuegian culpeo is the largest native terrestrial carnivore in Tierra del Fuego Island and, as such, may play a role on limiting some populations of introduced mammal species, which outnumber native species in this area by almost two to one (Valenzuela et al. 2014). Culpeos can consume large numbers of introduced mammals where these become abun
dant and in some cases even base the bulk of their diets on them (Jaksic et al. 1983; Novaro et al. 2000). The culpeo’s limiting effect on beaver populations would depend to some extent on the ability of this predator to switch among different prey, both introduced and native, as their numbers change in 
space and time, as has been shown for other canids (Letnic et al. 2012; Randa et al. 2009). In any case, our study suggests that a new and possibly strong interaction may have appeared in Tierra del Fuego involving culpeos and beavers as a source 
of food as prey or carrion, and perhaps even facilitating and interaction with other introduced prey, such as muskrats (Crego et al. 2016; Appendix).
We believe that three aspects of the reported interaction need to be considered due to their implications for management:
First, given the current distribution and abundance of beavers, the culpeo could have better predatory chances on these populations in suboptimal beaver habitats and in areas through which beaver are likely to disperse, where their vulnerability to predation may increase. Mainly, these would be streams
with shallow watercourses and areas away from streams. Furthermore, dispersing juveniles, smaller and perhaps with less defensive skills, would likely be more vulnerable to predation than adults.
Second, in Tierra del Fuego, there is currently an important removal effort to control beaver populations through trapping. 
Traps are being deployed and revised sporadically and often beaver carcasses consumed by foxes. It is unknown how this availability of carcasses may be subsidizing culpeo fox populations or other introduced canids such as chilla foxes 
(Pseudalopex griseus) or dogs. The latter increasing in importance, with feral dog populations reported becoming abundant at the Argentinean side of the Island (Schiavini and Narbaiza 2015).
Finally, this newly observed interspecific interaction
may have an impact on the health of Patagonic ecosystems as these close encounters and interactions could augment cross species transmission of pathogens, which in turn
have the potential to contribute to local wildlife extinctions (Daszak 2000; Harvell et al. 2002; Smith et al. 2006; Smith  et al. 2009).

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First records of culpeo (Lycalopex culpaeus) attacks and cooperative defense by guanacos (Lama guanicoe).

Observations were made during daylight hours in
January (austral summer) and June 2007 near the Vicuña ranger station of Karukinka Natural Park in Chilean Tierra del Fuego (54808920.50 S, 68842916.80 W). The habitat was a forest grassland mosaic of Southern beech trees
(Nothofagus pumilio and Nothofagus antarctica) and
meadows. In Tierra del Fuego, as in most studied sites, there is a guanaco birthing pulse during December (Raedeke 1979). Guanaco young weigh approximately 12 kg at birth and 33 kg by the following June (Sarno et al. 1999, B. Gonzalez personal communication).
On January 15 2007, as we observed a guanaco group

of nine adults and seven newly born young moving
through a patch of N. pumilio forest from approximately 50 m away, the young were attacked by an adult culpeo which started chasing them around a clump of Berberis sp. bushes. Two adult guanacos cornered the culpeo against a fallen tree and kicked it repeatedly with their front legs. The culpeo withdrew and repeated its charge at the young, with the adult guanacos charging again after the culpeo. The struggle lasted approximately 3 min. Eventually, the culpeo gave up and left. After the culpeo was gone the guanaco group quickly moved into a nearby meadow. One adult was bleeding from the nose
and another from the neck, but we could not determine if these injuries were inflicted by the culpeo or if the guanacos hurt themselves against fallen trees or bushes during the struggle. We could not see if any of the young were bitten inside the clump of bushes and none of the young appeared injured, but the group was sighted the following day and only six young were observed.
During late January 2007, on five occasions we
observed that guanacos from different family groups in the same study area reacted in a consistent manner to sightings and barks of culpeo and chilla. This response included the group quickly coming together, always where the young guanacos were, some adults approaching the sighted culpeo or chilla or the forest patch from where the barking came, and the group remaining vigilant until the predator left.
On June 13 2007, we observed an adult culpeo chasing a young guanaco in a snow-covered forest clearing around a dam built by invasive Canadian beavers (Castor canadensis) (Figure 1). The chase was observed during 5 min after the guanaco and culpeo came out of a N. pumilio forest patch, and continued at least until both guanaco and culpeo re-entered the same forest patch. Inside the clearing, both animals ran past within 5 m of the observers and both panted heavily, suggesting that the chase had been going on for some time when the animals came into the clearing. Wool that was the color
and length of guanaco hair hung from the culpeo’s muzzle, indicating that the culpeo had bitten the guanaco.
Guanaco young are not expelled from family groups
before the spring when they approach 1 year of age. As this guanaco was approximately 6 months old, it is possible that the culpeo had separated the young from its group before we spotted them. We cannot confirm this, however, because we did not observe the young interact with other guanacos nearby.
A comparison of our observations with those in pre-
vious studies (Bank and Franklin 1998) highlights the
behavioral plasticity of guanacos in displaying different anti-predatory strategies (flight or active defense) when faced with two predators that differ in body size and hunting strategy. A response based on detecting the predator at a certain distance and fleeing can be effective in facing a predator, such as the puma, which does not pursue its prey long distance, but may not be effective when faced with a cursorial predator (Creel and Creel 2002), such as the culpeo. The size difference between adult guanacos and culpeos, on the other hand, may make the risk of confrontation acceptable to guanacos.
Cooperative defense by guanacos when threatened by
culpeos may be an additional advantage of social group formation that adds to the benefits of dilution and early detection. This advantage is likely most significant during the first weeks after birth, when guanacos are most vulnerable to predation by culpeos due to their small size. Our records are similar to observations of interactions between female mule deer and coyotes, in which survival of the young depends upon the aggressiveness with
which female deer defend them (Lingle and Pellis 2002). Our observations also support the findings of Sarno et al. (1999), who reported that the young of more aggressive female guanacos were more likely to survive during the first year of life, although much of this advantage of aggressiveness may be related to dominance over other guanaco females. It is likely that in guanacos, as with mule deer, the probability that the young are protected successfully from predators increases as the number of females in the group becomes larger, highlighting the impact that social behavior can have on demographic
parameters (Lingle and Pellis 2002, Marino and Baldi
2008). Because culpeos occur almost everywhere where guanacos are present, and culpeos can be locally abundant (Novaro and Walker 2005), it is important to document how often culpeo attacks are successful and what are the demographic consequences of culpeo predation for guanaco populations.

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Native-predator–invasive-prey trophic interactions in Tierra del Fuego: the beginning of biological resistance?

The Magellanic sub-Antarctic ecoregion in southwestern South America is a remote area identified as one of the 24 wilderness regions remaining in the planet (Mittermeier et al. 2003). However, it has recently been invaded by several exotic mammal species, coming mainly from the northern hemisphere. One of the most
conspicuous and studied invasive species in the region is the American beaver (Castor canadensis). By building dams and cutting trees, beavers have modified large areas of forest into meadows, thereby greatly transforming the landscape (Henn et al. 2016). By creating ponds, beavers facilitate the establishment of other invaders, such as the muskrat (Ondatra zibethicus), which in turn, facilitates the rapid spread of another invasive mammal:
the American mink (Neovison vison; Crego et al. 2016). The impacts of these invasive species in Tierra del Fuego require further investigation so that we can better understand the implications for the evolution of the native communities in this remote and still unspoiled region of our planet. We examine the trophic relationship between the endemic Culpeo fox (Pseudalopex culpaeus) and the invasive muskrat on Tierra del Fuego, to compare with the nearby fox-free Navarino Island where the three invasive mammals have been previously described (Crego et al. 2016). Between December 2014 and February 2015, we conducted two expeditions along the Beagle Channel, on the southern edge of the large Island of Tierra del Fuego (Tierra del Fuego). One was to Caleta Ferrari in Yendegaia National Park (54°500 S, 68°490 W) and the other to Alberto de Agostini National Park,
specifically in the areas of Pia, Alemania, and Holanda
glaciers (see Crego et al. 2015). We monitored terrestrial mammals using camera-traps baited with canned fish, and indirect evidence such as scats, tracks, or the presence of burrows. We also recorded the presence of the native Culpeo fox and collected its scats to study its diet (Fig. 1). Additionally, we searched for evidence of other mammals’ activity, particularly of the American mink, the American beaver, and the muskrat.

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FIG. 1. Culpeo fox photographed using a camera trap in Caleta Ferrari, Yendegaia National Park, Tierra del Fuego, Chile.

The most prevalent prey item in the Culpeo’s diet
appears to be the invasive muskrat (Fig. 2). The muskrat, introduced to Tierra del Fuego in 1948, shared a similar motivation for the introduction of the mink and beavers, the fur industry (Jaksic et al. 2002). Nonetheless, to the best of our knowledge, the presence of muskrat in the diet of the native fox has not been previously reported, as was also the case of the abundant beaver (Wallem et al. 2007). The Culpeo is the apex predator in Tierra del Fuego. Reports of its diet consisted mainly of small native rodents and the medium-sized introduced lagomorphs (Oryctolagus cuniculus and Lepus europaeus), with occasional occurrence of birds and young guanacos (Lama guanicoe; Novaro et al. 2000). Despite similar to
us, Novaro et al. (2000) reported a high percentage in
occurrence (51%) and dry mass (83.5%) of introduced
mammals in Culpeo’s diet, they did not find muskrat
being consumed by native foxes between 1989 and 1994 (data collection time interval). Our findings show that the muskrat has become an important prey of the sampled foxes, being the second most frequent item and representing the highest percentage of dry mass in the scats (around 90% when it is present; Fig. 2C). This suggests that Culpeos are intensively preying on these invasive rodents and changing the proportion of previously prey in their diets. However, further investigation is needed to understand the strength and scale of this predator–prey interaction and the negative effects on the muskrat population. To accomplish this, it will be necessary to measure
the rates of muskrat consumption by Culpeos in Tierra del Fuego and the resulting impacts on foxes and muskrat’s per capita growth rate. Tierra del Fuego could be a case of native resistance to invasion because of consumption of an invasive species by a native predator. However, other important community-level consequences are expected from this new predator–prey interaction. Our predictions are that the mink would be affected by the Culpeo, as a competitor for the muskrat as prey, and/or as a potential prey, prediction than need to be tested with
empirical data, currently unavailable. Notwithstanding,
the nearby Navarino Island, offers a suitable point of
comparison with Tierra del Fuego, where mink, beavers, and muskrats interact in the absence of foxes. In this system, Crego et al. (2016) suggested two positive feedbacks among these invaders. By transforming the fast water rivers into meadow ponds, beavers create suitable habitat for muskrats. In turn, muskrats have become the main prey item for mink living in inland habitats, away from the seacoast. On Navarino Island, the mink is the only new top terrestrial predator; however, in Tierra del Fuego, the predator community includes two foxes and a
native otter (Valenzuela et al. 2014). Culpeo fox are
likely competing with mink consuming muskrat. What
could be the impacts on fox population and the other fox preys, under a complete or significant removal of the muskrat? Also interesting is the ecological role played by Culpeo foxes in Tierra del Fuego, potentially impacting muskrat populations would also impact on mink population through competitive mechanisms. An interesting aspect in this trophic network is that muskrat may increase apparent competition with native Culpeo’s prey, by subsidizing fox populations.

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Evolution, ecology and management converge when
biological invasions are studied (Allendorf and Lund-
quist 2003). Predator interactions in Tierra del Fuego are complex and multiple, and the muskrat may disrupt the natural predator–prey dynamics. On one hand, we must understand the natural history of the invaders as well as their potential native predators to prevent undesired management effects, such as the remotion of invasive preys might cause invasive predators to consume more native prey (Glen et al. 2013). On the other hand, a comparison of Tierra del Fuego with Navarino Island opens the opportunity to evaluate hypotheses in the field of community ecology (Shea and Chesson 2002) and
ecosystem level effects, such as cascade effects of native ecosystem response to invasive species (Strayer 2012). Carlsson et al. (2009) and Mooney and Cleland (2001) pointed out the need to identify mechanisms that explain how native predators respond to introduced prey and other predators in an evolutionary context. In a broader scope, we open the discussion on how the new communities formed will shape the course of evolution into the future. If we want to conserve pristine areas, like the sub-Antarctic Magellanic ecoregion, the question that arises is: would it be the same in the future if we do not
take into account the disruptions of evolutionary lines
into new communities and species interactions? We
believe that some insights can emerge from the study of the evolutionary trajectory of ecological networks and invasive species such as the example examined here.
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  • Claudiu Constantin Nicolaescu

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