Ecological Archives A023-023-A1

W. F. de Boer, S. van de Koppel, H. J. de Knegt, J. J. A. Dekker. 2013. Hibernation site requirements of bats in man-made hibernacula in a spatial context. Ecological Applications 23:502–514. http://dx.doi.org/10.1890/1051-0761-23.2.502

Appendix A.Detailed documentation of field data collection and used variables: six tables of temperature, one-to-one analyses, and squared Mahalanobis distances, and three figures, including a map of study sites, impact of human use on Myotis mystacinus/M. brandtii, and ecological-niche factor analysis (ENFA) analyses results for Myotis daubentonii and Plecorus auritus.

Methods

The New Dutch Waterline (NDW; a defense line covering roughly 85 × 4 km with 46 fortresses) was constructed from 1815 onwards. The line lost its defense function around 1940, and presently, there is a large variation in management, human use, and state of maintenance between the objects. Some of them remained property of the Ministery of Defence and are hardly disturbed, while others are used as campsite, museum, party center, or hotel. Some objects are open only in summer, others during the whole year (Schepel 2001; Will 2002; Visser 2004; Limpens et al. 2007; Schuring 2008). Some objects have a primary nature function.

Objects were visited once, between 15th of December and 15th of February of each year, and counts were performed by experienced and licensed bat workers. Census data was validated by provincial coordinators and the Dutch Mammal Society. Identification was done visually, as handling of hibernating bats is considered to cause unacceptable disturbance. This means that sibling species Myotis mystacinus and M. brandtii could not be distinguished. However, the abundance of M. brandtii in the Netherlands is very low (Van der Coelen and Verheggen 1997a,b; Mostert et al. 2004), and they are closely related and share many ecological characteristics with only minor differences (Stebbings 1988; Van der Coelen and Verheggen 1997a,b). Also both Pipistrellus species, Pipistrellus pipistrellus and P. nathusii, were combined due to identification problems.

Only bat data recorded during five winters (2003/2004 – 2007/2008) was used, because the conditions in and in the surroundings of the objects can change over time. These annual counts were averaged per object to calculate the bat abundance (i.e., number of individuals), both in total and per species. The response variables were measured at each objects as follows:


INTERNAL, NON-SPATIAL VARIABLES

 

EXTERNAL, NON-SPATIAL VARIABLES

 

EXTERNAL, SPATIAL VARIABLES

All spatial variables were gathered in seven buffers with a binary increasing radius from the object: 0.5, 1, 2, 4, 8, 16, and 32 km. As bats can fly several hundred metres up to 30 km, depending on the species (Limpens et al. 2007), it is expected that the used buffer size ranges are representative for the habitat of bats. Cover by water, built-up areas, natural and agricultural areas in the buffers were determined as the percentage of cover on topographic maps, using a grid cell size of 25 × 25 m in ArcGIS 9.3.1 (ESRI 2009), following the classification of Hazeu (2005):


LITERATURE CITED

ESRI. 2009. ArcGIS, v 9.3.1. ESRI, Redlands, USA.

Hazeu, G. W. 2005. Landelijk Grondgebruiksbestand Nederland (LGN5): vervaardiging, nauwkeurigheid en gebruik. Alterra report 1213. Alterra, Wageningen, The Netherlands.

Limpens, H. J. G. A., E. A. Jansen, and J. J. A. Dekker. 2007. Ondersteboven van de waterlinie: onderzoek naar gebruik door vleermuizen, knelpunten en mogelijkheden tot duurzame ontwikkeling in de Nieuwe Hollandse Waterlinie; part 3, onderzoeksrapportage. Report 2006.54.3. Zoogdiervereniging VZZ, Arnhem, The Netherlands.

Masing, M., and L. Lutsar. 2007. Hibernation temperatures in seven species of sedentary bats (Chiroptera) in northeastern Europe. Acta Zoologica Lituanica 17:47–55.

Mostert, K., K. Spoelstra, and J. P. Bekker. 2004. The occurrence of whiskered bat (Myotis mystacinus) and Brandt's bat (Myotis brandtii) in the Netherlands. Lutra 48:57–64.

Schepel, S. 2001. De waterlinie in de eenentwintigste eeuw. Pages 105–149 in A. de Haas, editor. De Nieuwe Hollandse Waterlinie. Waanders Uitgevers, Zwolle, The Netherlands.

Schuring, H. 2008. Langs de linie: ontdek natuur, cultuur & landschap van de Nieuwe Hollandse Waterlinie. ANWB Media & Projectbureau Nieuwe Hollandse Waterlinie, Den Haag, The Netherlands.

Stebbings, R. E. 1988. Conservation of European Bats. Christopher Helm Publishers, Kent, UK.

Van der Coelen, J. E. M., and L. S. G. M. Verheggen. 1997a. Brandts vleermuis Myotis brandtii (Eversmann, 1845). Pages 81–82 in H. J. G. A. Limpens, K. Mostert, and W. Bongers, editors. Atlas van de Nederlandse vleermuizen: onderzoek naar verspreiding en ecologie. Stichting Uitgeverij van de Koninklijke Nederlandse Natuurhistorische Vereniging, Utrecht, The Netherlands.

Van der Coelen, J. E. M., and L. S. G. M. Verheggen. 1997b. Gewone baardvleermuis Myotis mystacinus (Kuhl, 1819). Pages 72–80 in H. J. G. A. Limpens, K. Mostert, and W. Bongers, editors. Atlas van de Nederlandse vleermuizen: onderzoek naar verspreiding en ecologie. Stichting Uitgeverij van de Koninklijke Nederlandse Natuurhistorische Vereniging, Utrecht, The Netherlands.

Visser, A. R. 2004. De begrenzing van de historische Nieuwe Hollandse Waterlinie. Pages 121–136 in H.C.M. Kleijn, R.J.A. Van Suchtelen van de Haare, D. A. Hierick, B. A. van Tilburg, and A. de Vries, editors. Op weerstand gebouwd: verdedigingslinies als militair erfgoed. Waanders Uitgevers, Zwolle, The Netherlands.

Walsh, A. L., and S. Harris. 1996. Factors determining the abundance of vespertilionid bats in Britain: geographical, land class and local habitat relationships. Journal of Applied Ecology 33:519–529.

Webb, P. I., J. R. Speakman, and P. A. Racey. 1996. How hot is a hibernaculum? A review of the temperatures at which bats hibernate. Canadian Journal of Zoology 74:761–765.

Will, C. 2002 Sterk water: de Hollandse Waterlinie. Uitgeverij Matrijs, Utrecht, The Netherlands.


 

Table A1. Air temperatures at which bat species that are present in the NDW have been recorded hibernating in the wild (based on Webb et al. 1996; Masing and Lutsar 2007); na = not available.

Species

Minimum temp. (°C)

Maximum temp. (°C)

Eptesicus serotinus Schreber

0.5

6.5

Myotis brandtii Eversmann

-2.5

10.0

Myotis dasycneme Boie

-2.5

10.6

Myotis daubentonii Kuhl

-3.0

11.0

Myotis mystacinus Kuhl

0.0

10.3

Myotis nattereri Kuhl

-3.0

10.5

Pipistrellus nathusii Keyserling & Blasius

na

na

Pipistrellus pipistrellus Schreber

-5.0

12.0

Plecotus auritus L

-2.5

9.7

 

Table A2. Results of one-by-one regressions and correlations between total bat abundance (Ln-transformed) and non-spatial variables. Only significant results are depicted.

Variable

Prediction

n

Linear regression

 

Spearman correlation

B

t

P

R²adj

 

r

P

VO

+

40

0.001

5.603

<0.001*

0.438

 

 

 

AR

+

40

0.137

6.377

<0.001*

0.504

 

 

 

NH

+

39

0.006

5.358

<0.001*

0.422

 

 

 

WT

+

40

 

 

 

 

 

 

 

TA

-+-

30

 

 

 

 

 

 

 

TX

-

30

 

 

 

 

 

 

 

TN

-

30

 

 

 

 

 

 

 

TS

-

30

-0.994

-2.121

0.043

0.108

 

 

 

TR

-

30

 

 

 

 

 

 

 

TD

-

30

 

 

 

 

 

 

 

TZ

-

30

 

 

 

 

 

 

 

HA

+

30

 

 

 

 

 

 

 

HX

+

30

 

 

 

 

 

 

 

HN

+

30

 

 

 

 

 

 

 

HS

-

30

 

 

 

 

 

 

 

HR

-

30

 

 

 

 

 

 

 

HD

-

30

 

 

 

 

 

 

 

DR

-

40

 

 

 

 

 

 

 

GC

+

40

 

 

 

 

 

0.432

0.005

GS

+

40

 

 

 

 

 

 

 

OV

-

36

 

 

 

 

 

 

 

VI

-

40

 

 

 

 

 

 

 

* = relationship significant after Bonferroni correction

 

Table A3. Results of one-by-one GzLM and correlations between species richness and non-spatial variables. Only significant results are depicted.

Variable

Prediction

n

GzLM Poisson

 

Spearman correlation

B

Wald Χ²

P

AIC

 

r

P

VO

+

56

4.67*10-4

37.901

<0.001*

171.507

 

 

 

AR

+

55

0.049

47.376

<0.001*

162.331

 

 

 

NH

+

55

0.002

32.498

<0.001*

168.785

 

 

 

WT

+

41

 

 

 

 

 

 

 

TA

-+-

41

0.210

6.492

0.011

133.810

 

 

 

TX

-

44

 

 

 

 

 

 

 

TN

-

44

 

 

 

 

 

 

 

TS

-

44

 

 

 

 

 

-0.299

0.048

TR

-

44

 

 

 

 

 

 

 

TD

-

44

 

 

 

 

 

 

 

TZ

-

44

 

 

 

 

 

 

 

HA

+

44

 

 

 

 

 

 

 

HX

+

44

 

 

 

 

 

 

 

HN

+

44

 

 

 

 

 

 

 

HS

-

44

 

 

 

 

 

 

 

HR

-

44

 

 

 

 

 

 

 

HD

-

44

 

 

 

 

 

-0.353

0.019

DR

-

56

 

 

 

 

 

0.350

0.008

GC

+

56

 

 

 

 

 

0.393

0.003

GS

+

56

 

 

 

 

 

 

 

OV

-

52

 

 

 

 

 

0.346

0.012

VI

-

56

 

 

 

 

 

 

 

* = relationship significant after Bonferroni correction

 

Table A4. Results of one-by-one regressions and correlations between abundance (Ln-transformed) and presence/absence of Myotis daubentoni and non-spatial variables. Only significant results are depicted.

 

Variable

 

Prediction

 

Presence/absence

 

Linear regression

Spearman correlation

Logistic regression

n

B

t

P

R²adj

r

P

n

B

Wald

P

R²

VO

+

22

0.001

2.464

0.023

0.195

 

 

56

0.005

12.184

<0.001*

0.487

AR

+

22

0.075

2.368

0.028

0.180

 

 

56

0.324

11.671

0.001*

0.481

NH

+

21

0.004

2.640

0.016

0.230

 

 

55

0.029

10.616

0.001*

0.494

WT

+

22

 

 

 

 

 

 

56

 

 

 

 

TA

-+-

18

 

 

 

 

 

 

44

 

 

 

 

TX

-

18

 

 

 

 

 

 

44

 

 

 

 

TN

-

18

 

 

 

 

 

 

44

 

 

 

 

TS

-

18

 

 

 

 

 

 

44

 

 

 

 

TR

-

18

 

 

 

 

 

 

44

 

 

 

 

TD

-

18

 

 

 

 

 

 

44

 

 

 

 

TZ

-

18

 

 

 

 

 

 

44

 

 

 

 

HA

+

18

 

 

 

 

 

 

44

 

 

 

 

HX

+

18

 

 

 

 

 

 

44

 

 

 

 

HN

+

18

 

 

 

 

 

 

44

 

 

 

 

HS

-

18

 

 

 

 

 

 

44

 

 

 

 

HR

-

18

 

 

 

 

 

 

44

 

 

 

 

HD

-

18

 

 

 

 

 

 

44

 

 

 

 

DR

-

22

 

 

 

 

 

 

56

0.020

5.180

0.023

0.132

GC

+

22

 

 

 

 

 

 

56

0.013

10.554

0.001*

0.374

GS

+

22

 

 

 

 

 

 

56

 

 

 

 

OV

-

22

 

 

 

 

 

 

52

0.059

7.488

0.006

0.220

VI

-

22

 

 

 

 

 

 

56

 

 

 

 

* = relationship significant after Bonferroni correction

 

Table A5. Results of one-by-one regressions and correlations between abundance (Ln-transformed) and presence/absence of Plecotus auritus and non-spatial variables. Only significant results are depicted.

 

Variable

 

Prediction

 

Presence/absence

 

Linear regression

Spearman correlation

Logistic regression

n

B

t

P

R²adj

r

P

n

B

Wald

P

R²

VO

+

31

0.001

5.810

<0.001*

0.522

 

 

56

0.004

7.409

0.006

0.313

AR

+

31

0.064

5.352

<0.001*

0.480

 

 

56

0.282

7.728

0.005

0.339

NH

+

30

0.003

5.014

<0.001*

0.454

 

 

55

0.026

7.480

0.006

0.356

WT

+

31

0.008

2.247

0.032

0.119

 

 

56

 

 

 

 

TA

-+-

23

 

 

 

 

 

 

44

 

 

 

 

TX

-

23

 

 

 

 

 

 

44

 

 

 

 

TN

-

23

 

 

 

 

 

 

44

 

 

 

 

TS

-

23

 

 

 

 

 

 

44

 

 

 

 

TR

-

23

 

 

 

 

 

 

44

 

 

 

 

TD

-

23

 

 

 

 

 

 

44

 

 

 

 

TZ

-

23

 

 

 

 

 

 

44

 

 

 

 

HA

+

23

 

 

 

 

 

 

44

 

 

 

 

HX

+

23

 

 

 

 

 

 

44

 

 

 

 

HN

+

23

 

 

 

 

 

 

44

 

 

 

 

HS

-

23

 

 

 

 

 

 

44

 

 

 

 

HR

-

23

 

 

 

 

 

 

44

 

 

 

 

HD

-

23

 

 

 

 

 

 

44

-0.443

5.682

0.017

0.207

DR

-

31

 

 

 

 

 

 

56

0.020

5.275

0.022

0.129

GC

+

31

 

 

 

 

 

 

56

 

 

 

 

GS

+

31

 

 

 

 

 

 

56

 

 

 

 

OV

-

27

 

 

 

 

 

 

52

0.040

4.129

0.042

0.115

VI

-

31

 

 

 

 

 

 

56

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

* = relationship significant after Bonferroni correction

 

Table A6. Squared Mahalanobis distances for total bat abundance of four different response variables (Total bat abundance, total number of species and number of bats for Myotis daubentoni and Plecotus auritus) against each of the spatial variables over different buffer sizes. The highest Mahalanobis distance per variable is underlined, indicating the most important buffer size per variable.

Response

Buffer size

CW

CB

CN

CA

LL

NO

NB

NS

DN

N total

0.5

0.77

1.33

1.98

1.91

0.92

5.37

0.43

0.96

NA

 

1

0.77

1.66

1.97

1.66

0.75

4.78

0.47

1.19

0.76

 

2

0.90

1.84

1.76

1.43

0.79

3.45

1.10

1.59

0.87

 

4

1.07

1.57

1.12

1.07

1.01

2.36

1.17

1.31

0.95

 

8

1.09

1.19

1.11

0.99

1.13

1.08

1.07

1.18

1.07

 

16

1.03

1.05

1.14

1.00

0.86

1.35

1.33

1.02

1.19

 

32

0.97

0.67

0.91

0.90

0.90

0.68

0.73

1.29

1.29

N Spp

0.5

0.78

1.21

2.03

1.63

0.87

4.56

0.43

0.97

NA

 

1

0.78

1.44

2.09

1.45

0.73

4.14

0.46

1.08

0.69

 

2

0.92

1.58

1.73

1.29

0.77

3.34

1.00

1.40

0.76

 

4

1.05

1.43

1.05

0.98

0.93

2.19

1.11

1.26

0.81

 

8

1.13

1.10

1.06

0.93

1.05

1.05

1.02

1.21

0.99

 

16

1.01

1.00

1.05

0.96

0.88

1.24

1.24

1.03

1.09

 

32

0.97

0.78

0.87

0.92

0.95

0.69

0.74

1.26

1.14

Myotis daubentoni

0.5

0.81

1.24

1.97

2.03

1.02

4.85

0.48

1.19

NA

 

1

0.95

1.80

1.92

1.87

0.81

4.66

0.50

1.30

0.79

 

2

1.24

2.12

1.41

1.61

0.76

6.32

1.21

2.44

0.87

 

4

1.17

1.85

0.99

1.13

0.99

2.99

1.18

1.32

0.94

 

8

1.04

1.35

1.05

0.99

1.18

1.13

1.21

1.32

1.15

 

16

0.90

1.15

1.25

0.95

0.78

1.63

1.53

1.03

1.38

 

32

0.83

0.65

0.90

0.77

0.78

0.68

0.70

1.50

1.51

Plecotus auritus

0.5

0.73

1.36

1.61

1.46

0.91

5.25

0.35

0.90

NA

 

1

0.72

1.37

1.90

1.37

0.74

4.16

0.37

0.98

0.89

 

2

0.88

1.42

2.08

1.16

0.75

3.15

1.05

1.18

1.04

 

4

1.12

1.29

1.31

1.02

1.00

2.37

1.07

1.27

1.13

 

8

1.21

1.00

1.09

0.94

1.14

0.92

0.98

1.16

1.18

 

16

1.20

0.94

1.00

1.01

1.00

1.13

1.21

1.04

1.14

 

32

1.15

0.79

0.95

1.08

1.09

0.74

0.78

1.23

1.15

NA=Not applicable

 

 

 

 

 

 

 

 

 

 

 

Fig a1

Fig. A1. Map of the location of the New Dutch Waterline in the Netherlands with a detail of the defence line. Detail picture (on the right): black dots represent the larger forts and fortified areas; dark gray areas represent the land that could be inundated (source: http://en.wikipedia.org/wiki/New_Dutch_Waterline).


 

Fig A2

Fig. A2. Bar graph (mean ± SE), showing the negative effect of humans use (a) and public access of objects (b) on abundance of Myotis mystacinus/M. brandtii, on the basis of volume corrected residuals.


 

FigA3a

 

Fig A3b

Fig. A3. ENFA scatter plot with the marginality axis (x-axis) and the first specialization axis (y-axis) for and the number of bats for Myotis daubentonii (a) and Plecorus auritus (b). Light gray: the ecological space of all available hibernation objects. Dark gray: the ecological dimension of the objects used for hibernation. Arrows illustrate the correlation of the habitat composition over the marginality (horizontal) and first specialization (vertical) axes, where longer arrows along the x-axis indicate that a particular variable is either positively or negatively selected. The size of the arrows along the y-axis indicates the degree to which the bats restricted their choices and is independent of the direction of the arrow. For correlation values of the environmental variables, refer to Table 4. The inset bar graphs display the eigenvalues/variance ratio per specialization axis.


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