# Feeding habits and trophic niche overlap between sympatric golden jackal (Canis aureus) and red fox (Vulpes vulpes) in the Pannonian ecoregion (Hungary)

> Golden jackals are moving back into Hungary, where red foxes had the field to themselves. Four years of scats showed that both live mainly on voles, but when a hard winter made voles scarce, jackals turned to wild boar piglets and carcasses while foxes turned to fruit and birds. The newcomer turned out to be the pickier eater.

Summary by Kersey Lawrence, Original Wisdom. Updated 9 November 2026. Page: https://www.originalwisdom.com/tracking-literature/2006-lanszki-heltai-feeding-habits-trophic-niche/

## Citation and access

- **Authors:** József Lanszki, Miklós Heltai and László Szabó
- **Year published:** 2006
- **Journal or source:** Canadian Journal of Zoology
- **Full citation:** Lanszki, J., Heltai, M. and Szabó, L. 2006. Feeding habits and trophic niche overlap between sympatric golden jackal (Canis aureus) and red fox (Vulpes vulpes) in the Pannonian ecoregion (Hungary). Canadian Journal of Zoology 84(11): 1647–1656.
- **DOI:** 10.1139/z06-147
- **Access status:** Publisher link only
- **Where to find it:** https://doi.org/10.1139/z06-147

## Tags

- **Species:** Mammals > Golden jackal; Mammals > Red fox
- **Region:** Europe > Hungary
- **Tracking:** Scat; Sign surveys; Tracking; Tracks and signs identification
- **Behaviour and ecology:** Behaviour; Carnivore coexistence; Feeding; Hunting; Interspecific competition; Predation; Range expansion; Scavenging
- **Methods and technology:** Capture-mark-recapture; Chi-square test; Linear regression
- **Data type:** New field data
- **Observer qualification:** Not reported
- **Discipline:** Behaviour and ecology; Wildlife tracking
- **Year published:** 2006

## Detailed keywords

- **Species:** Studied: golden jackal (Canis aureus) and red fox (Vulpes vulpes). Food remains found in scats: common vole (Microtus arvalis, the main prey), field mice (Apodemus species), bank vole (Clethrionomys glareolus), European water vole (Arvicola terrestris), muskrat (Ondatra zibethicus), hazel dormouse (Muscardinus avellanarius), harvest mouse (Micromys minutus), gleaner mouse (Mus spicilegus), shrews (Sorex and Crocidura species), brown hare (Lepus europaeus), wild boar (Sus scrofa, mainly piglets and carcasses), cervids (deer, mostly hunters’ remains), common pheasant (Phasianus colchicus), other birds, snakes, lizards, fish, invertebrates, least weasel (Mustela nivalis), martens (Martes species), red fox (in one jackal scat), domestic cattle and pig carcasses, domestic cats and dogs, fruits, seeds and other plants. In the study area but not studied: red deer (Cervus elaphus), fallow deer (Dama dama), western roe deer (Capreolus capreolus), Eurasian badger (Meles meles), European pine marten (Martes martes), beech marten (Martes foina), European otter (Lutra lutra), wild cat (Felis silvestris), domestic sheep. Stray dogs were very rare or absent. Comparison species from other studies: coyote (Canis latrans), gray fox (Urocyon cinereoargenteus), black-backed jackal (Canis mesomelas), side-striped jackal (Canis adustus), swift fox (Vulpes velox).
- **Location and habitat:** Pannonian ecoregion, southwestern Hungary, central Europe (45°56’N, 17°41’E; 20.5 km²), on the northern edge of the golden jackal’s range, in an area the jackal has recently recolonized. Mostly arable farmland: a mosaic of cultivated land (cereals and soybean, 34.5%), abandoned fields (31.3%), oak, elm and ash forest (26.5%) and willow and blackthorn shrubs (7.8%). Continental climate; 2003 had an especially cold, long winter and a hot, dry summer. Intensive trophy hunting of deer. Domestic animal carcasses were dumped 2.2 km from the study area. Scats were collected on a standard route in a 650 ha area, about 1.6 km from settlements.
- **Topics:** diet analysis by scat analysis, feeding ecology, trophic niche breadth and overlap, interspecific competition, carnivore coexistence, mesocarnivores, range expansion and natural recolonization, small-mammal specialization, prey switching after a decline in small mammals, searcher versus pursuer hunting strategies, scavenging on wild boar and domestic carcasses, fruit eating, prey size classes, small-mammal abundance, scat identification of jackal versus fox. Possible inconsistencies in the paper: (1) the abstract says foxes consumed more small mammals than jackals, but its own figures (jackal 77%, fox 68%) and the results say jackals ate significantly more; (2) for prey of 15 to 50 g the results first give jackal 81.8% and fox 83.6%, then jackal 76.0% and fox 64.3% (the second pair matches Figure 3 and the abstract’s “under 50 g: 92% and 87%”); (3) prey over 300 g is given as 16.1% and 13.1%, but all prey over 50 g as only 8.2% and 12.8%. The first set of figures may be biomass rather than frequency, but the paper does not say.
- **Statistics or models:** relative frequency of occurrence (%O) and percentage of biomass consumed (%B) with conversion factors; general log-linear likelihood tests with Bonferroni correction; paired samples t test; multivariate analysis of variance (MANOVA, SPSS 10.0) with least significant difference (LSD) post hoc tests; chi-square test on prey mass classes; Levins’ standardized niche breadth (BA); Renkonen index of niche overlap; linear regression. Small-mammal density by live-trap mark-recapture (minimum number alive, MNA, per hectare). Relative abundance of jackals and foxes as scats per km of route; jackal family groups by howling counts and stimulated calling; fox density from harvests and den density.
- **Data type:** New field data: scats collected monthly from December 2000 to November 2004 (814 jackal and 894 fox scats); small mammals trapped seasonally from October 2001 to October 2004. Hunting-bag data 2000 to 2004 from the Hungarian game management database (existing data). Supplementary Tables S1 and S2 are on the journal website.

## Synopsis

### 1. What they did

Golden jackals died out in Hungary by the early 1900s and have recently come back on their own. Little is known about their role in this new range, or how they share food with red foxes, which until then had been the only wild canid there. The researchers tested two ideas: that the larger jackal would eat more hoofed animals and be more of a generalist than the fox, and that the two species’ diets would overlap less as they divided up food.

- Collecting scats. Every month from December 2000 to November 2004, they walked a standard route (12.8 to 22.7 km) through farmland, forest and shrubs in southwestern Hungary and collected jackal and fox scats.

- Telling jackal from fox. They identified scats by smell, size and shape. Jackals often leave piles of scats within a circle of 1 to 1.5 m; individual scats in these piles were separated by age (if known), visible content and colour. Predator hairs found in the scats were identified under the microscope. The route was kept away from villages to avoid dog scats, and questionable samples (1% to 2%) were left out.

- Analysing diet. In the laboratory, 814 jackal and 894 fox scats were washed and sieved, and the food remains identified with keys and reference collections. They worked out how often each food appeared and estimated how much of the diet each made up by weight.

- Measuring food supply. Small mammals were live-trapped each season from October 2001 to October 2004.

- Comparing the two predators. They compared diets between species, seasons and years, and calculated how broad each diet was (niche breadth) and how much the two overlapped.

### 2. What they found

What they ate

- Small mammals were the main food of both. They made up about 77% of the jackal’s diet by weight and 68% of the fox’s. The common vole was by far the most important prey, followed by field mice.

- For jackals, wild ungulates (especially wild boar, mainly piglets in spring) were the second most important food. Deer appeared rarely, mostly from remains left by hunters.

- For foxes, plants (mainly fruit) were the second most important food, at about 18% of the diet by weight compared with about 6% for jackals.

- Both scavenged on wild boar and on domestic cattle and pig carcasses from a nearby dump. Brown hare, pheasant, other birds, reptiles, fish and invertebrates were eaten only in small amounts.

- No killing of livestock and no garbage eating were found.

- One jackal scat contained fox remains; whether the fox was killed or scavenged is unknown.

Prey size

- Both mostly ate small prey. Prey of 15 to 50 g appeared more often in jackal scats (76.0%) than in fox scats (64.3%); foxes ate more very small prey (under 15 g) and more prey over 50 g.

Changes over time

- After the severe winter of 2003 and the dry summer that followed, small mammals became scarce. Both predators ate fewer of them.

- Jackals switched mainly to wild boar (piglets and carcasses), domestic carcasses and plants; foxes to other birds and plants.

- Jackals switched earlier and returned to small mammals earlier, in 2004, when small mammals were plentiful again. Foxes kept eating more fruit and other foods through 2003 and 2004.

- Foxes’ diets varied more between seasons and years than jackals’ did.

Niche breadth and overlap

- Both diets were very narrow. Jackals had the narrower diet (standardized breadth 0.06 versus 0.09 for foxes), so they were more of a specialist.

- Diet overlap was high, 73% on average. It was 84% and 81% in 2001 and 2002, and fell to 60% in 2003 and 66% in 2004.

- Overlap rose as foxes ate more small mammals, but showed no clear link with how many small mammals jackals ate.

### 3. What they concluded

- Contrary to their first prediction, the golden jackal was more carnivorous and more specialized than the red fox, and the differences between the two species’ diets were smaller than expected.

- The high share of small rodents points to both being mainly solitary searching hunters. Jackals may have hunted wild boar piglets or injured ungulates cooperatively or scavenged them, but the paper could not tell how much was hunted and how much scavenged.

- Supporting their second prediction, the two predators reduced their high overlap by turning to different foods when small mammals were scarce. The ability to share food may help them live side by side, as close relatives can when the most important resources are plentiful.

- No evidence of competition between the two in the region has been reported, although the jackal may be the dominant competitor, being about twice the fox’s size.

- The jackal’s particular feeding habits may play an important part in its recent spread into central Europe.

### 4. How tracking was or was not used

The study rests on scat identification. The researchers collected scats along a fixed route every month for four years and told jackal from fox scats by smell, size and shape, using the jackal’s habit of leaving scats in piles, and confirmed with microscope identification of predator hairs in the scats. They separated individual scats within piles by age, content and colour. Scats per kilometre of route were also used as a measure of how common each species was. No following of tracks was reported.

### 5. Tracker or observer certification

Not reported. The paper does not say who collected or identified the scats, or how reliable the jackal versus fox identification was, although the whole diet comparison depends on it.

### 6. Other technologies, skills or innovations

- Laboratory scat analysis: washing through a 0.5 mm sieve, drying, and identifying bones, hair, feathers and plant remains under the microscope with keys and the authors’ own reference collections.

- Converting dry remains into the fresh weight of food eaten, with different factors for each food type and lower digestibility values where scavengers ate bone and skin.

- Live-trapping small mammals with 199 to 299 glass-doored wooden traps per session to track how much prey was available.

- Howling counts and stimulated calling to count jackal family groups (at least three).

### 7. Implications for conservation (from the paper)

- The spread of the jackal raises conservation and management questions, and its role in its new range is barely known.

- From a wildlife management point of view, the results did not confirm damage by jackals to ungulates or small game.

- Being able to share food resources may help the jackal and fox live together in the region.

### 8. Implications for tracking (Original Wisdom's observations)

_These are Original Wisdom's observations, not the authors'._

- Diet studies of two similar species stand or fall on telling their scats apart. Here identification used smell, size, shape, the jackal’s scat piles and hair checks, but its accuracy was not tested, so it is worth knowing what checks were used when reading such comparisons.

## Cite this summary

Lawrence, K. 2026. Summary of: Feeding habits and trophic niche overlap between sympatric golden jackal (Canis aureus) and red fox (Vulpes vulpes) in the Pannonian ecoregion (Hungary) (Lanszki and Heltai et al., 2006). Original Wisdom, Tracking Literature. https://www.originalwisdom.com/tracking-literature/2006-lanszki-heltai-feeding-habits-trophic-niche/