Engineers in the forest.

How do foxes and badgers modify

forest vegetation?

Joanna Czarnecka1, Justyna Sokal1,

Przemysław Kurek2, Jan Holeksa3

1Maria Curie-Skłodowska University, Lublin, Poland2Institute of Botany, Polish Academy of Sciences, Kraków, Poland3A. Mickiewicz University, Poznań, Poland 

The entrance to burrow of the fox (Vulpes vulpes)

Introduction or…

…what was the starting point of our study

Ecosystem engineers modify the

availability of resources to other species

They cause physical changes in biotic

and abiotic matter, but do not influence

trophic interactions directly

Jones CG., Lawton J.H., Shachak M. 1994. Oikos

Introduction

Ecosystem engineers

create, modify or maintain

existing habitats

Introduction

Animals building nests and burrows are good

example of engineering species

The primary function of the nests:

hazard mitigation

1. Nests are habitats theirselves

2. Nests affect habitats in which they are built

But also:

Introduction

Girlatovce, eastern Slovakia, 2009

Nest as habitats

Nests of the white stork (Ciconia

ciconia) are habitats for many

plant and animal species.

Seedlings of 97 plant species (Czarnecka, Kitowski 2013)

1 2 3 4 5 6 7 8 9 100

5

10

15

20

25

30

Tota

l N c

onte

nt (

g kg

-1)

Nest number

Average content in Polish soils

Study aim

Burrows affect habitats in which they are built

Fox (Vulpes vulpes) and badger (Meles meles) disperse seeds

and deposit them with faeces

D + D

DisturbanceSett of badger

DispersalFaeces on ”the dormant”

Study aim

How do the activity of animals influence

qualitative and quantitative structure

of understorey trees and shrubs

in the vicinity of burrows?

Local patches versus matrix

The nest closest vicinity versus forest floor vegetation

Source: commons.wikimedia.org

Study site and methods

Landscape parksNational parks

Lublin

Poznań

Kraków

The Kampinos National Park

Warsaw

Study site and methods

The Vistula river

Warsaw

The Kampinos National Park (KNP)

Source: Matuszkiewicz 2003

Pine and mixed oak-pine forest

Pine and mixed oak-pine forest

Ash-alder forests

Ash-alder forestsAsh-alder forests

Potential landscape fito-compexes of KNP

Oak-hornbeam and mixed forests

Oak-hornbeam and mixed forests

Oak-hornbeam and mixed forests

Oak-hornbeam and mixed forests

Studied burrows (N = 36)

Study site and methods

Matrix

Patches

Burrow plot100 m2

Control plot100 m2

50 m

Badger

N = 19 burrows exploited intensively all

over the year more complex structure

Fox

N = 17 burrowsexploited less intensively mostly

in mating season and during winter smaller and simpler structure

All plant individuals

were counted

Matrix differences

Burrowing places – preferences of studied animal species

Badger

versus

fox

Higher clay and silt content

Higher soil fertilityHigher content of:

total carbon (C) total nitrogen (N) magnesium (Mg) calcium (Ca) potassium (K)

Plant communities

with higher tree species

richness

and greater broadleaved

trees admixture

Source: Kurek et al. 2014

Matrix differences – control plots

Burrowing places – preferences of studied animal species

BadgerN = 19

FoxN = 17

Total number of species (trees and shrubs) 18 12

Frequency (%)

Frangula alnus 89 76

Sorbus aucuparia 79 35

Pyrus communis 42 18

Padus avium 26 6

Juniperus communis 32 53

Mean diversity measures

0

1

2

3

4

5

Badger Fox

Species number

P <0.05(U-test)

*

Shannon diversity

-2.22044604925031E-16

0.2

0.4

0.6

0.8

1

1.2

1.4

NS

23 tree and shrub species were found in total

Influence of the animal activity

PATCHES (burrow plots) versus MATRIX (control plots)

Meannumber

of individuals

Badger

All species Frangula alnusNS

NS

0

10

20

30

40

50

05

101520253035404550

Meandiversitymeasures

Species number Shannon diversityP <0.01

(Wilcoxon test)**

0

1

2

3

4

5

6

7

0

0.4

0.8

1.2

1.6

2

**P <0.01

(paired samples

t-test)

Influence of the animal activity

PATCHES (burrow plots) versus MATRIX (control plots)

Badger

Control plotBurrow plot

Matrix

Patches

Axis 1 and diversity index: Sr = +0.84; p < 0.0001

Axis 1 and number of species: Sr = +0.45; p < 0.01

Axis 1 and abundance of F. alnus: Sr = -0.65; p < 0.0001

50 m

DCA

Influence of the animal activity

PATCHES (burrow plots) versus MATRIX (control plots)

Fox

www.wikimedia (Malene)

Meannumber

of individuals

All species Frangula alnus

NS NS

05

1015202530354045

0

10

20

30

40

50

Meandiversitymeasures

Species number Shannon diversity

0

1

2

3

4 P <0.05(Wilcoxon test)*

0

0.5

1

1.5

2 P <0.05(paired

samples t-test)*

Influence of the animal activity

PATCHES (burrow plots) versus MATRIX (control plots)

Fox

www.wikimedia (Malene)

Control plotBurrow plot

No obvious pattern

Axis 1 and number of species: Sr = +0.53; p < 0.01

Axis 1 and abundance of F. alnus: Sr = +0.82; p < 0.0001

DCA

What is more important?

D or D? DISTURBANCE or DISPERSAL?

Sample – frequencies (%) of particular species, N = 23

SpeciesBadger Fox

Matrix Patches Faeces Matrix Patches Faeces

1 Frangula alnus 89 89 0.7 76 82 0.7

2 Rhamnus catharticus 5 21 - - 12 -

3 Cerasus avium 11 26 10.1 6 12 5.1

Low impact

Disturbance

Dispersal

Is any general pattern there?

What is more important?

D or D? DISTURBANCE or DISPERSAL?

Sample – frequencies (%) of particular species, N = 23

Spearman rank correlation for frequencies

Badger Fox

In patchesand

in matrix

In patchesand

in faeces

Disturbanceand

seed source

Dispersal

Sr = 0.42; p < 0.05 Sr = 0.57; p < 0.01

Sr = 0.47; p < 0.05 Sr = 0.54; p < 0.01

Both are important!

Conclusions

1.Burrowing animals create patches which

are different from forest vegetation

2.They cause evident increase of local plant

species diversity. The result depends on

animal species

3.There are two main aspects of animal

activity: disturbance and internal seed

dispersal and their importance differs for

different plant species