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Litter Sizesand Breeding Seasons

of Hedgehogs in Germany

Monika Neumeier

Edited by Pro Igel e.V.

3. Edition, Reissue

Litter Sizes and Breeding Seasons of Hedgehogs in germany

Bibliographic Information published by the Deutsche Nationalbibliothek

data is available in the Internet at http://dnb.dnb.de.

Reference:This work and all its parts are protected by copyright. Application outside the limits of copyright law without consent having been obtained from Pro Igel e.V. is inadmissible. No part of this publication may be reproduced or transmitted in any form or by any means without permission in writing from the publisher.

All Rights reserved3. Edition, Reissue 2016© Pro Igel e.V., Lindau/B. & M. Neumeier, Lindau/B.

Cover Photography: Reinhard-Tierfoto, HeiligenkreuzsteinachEditorial Management: Ulli Seewald, Münster/Westf.Layout and Typesetting: Pamela Kröhl, Niestetal, Ulli Seewald, Münster/Westf.Printed and bound in Germany by: Häuser KG, KölnCover Design: Pamela Kröhl, Niestetal

Photo Credits:

-

ISBN 978-3-940377-16-6

Correspondence and inquiries to:Pro Igel e.V. E-Mail: [email protected]

Actual Informations in the Internet under www.pro-igel.de

05

Preface to the Reissue

This book by Monika Neumeier is a milestone in knowledge about our native brown breasted hedgehog. The author has been an outstanding expert in the the-ory and practice of everything to do with hedgehogs (Erinaceus europaeus Linna-

eus 1758) for more than four decades, has written numerous books and publications on hedgehogs and is the initiator and co founder of the Society Pro Igel e.V.

In this study, Monika Neumeier has swept away longstanding errors based on as-sumptions which academics and others still publish today about the reproduction,

of a large collection of data on almost 2000 litters over many years, Neumeier proves

biological knowledge about hedgehogs but is essential for meaningful and appropriate hedgehog care and for constructive endeavours in hedgehog and wildlife conservation.

All this is reason enough for the Society and Publisher Pro Igel e.V. to issue this

compact” - with thanks to our tireless author for her commitment to hedgehogs.

Münster, Westph., September 2016

Ulli Seewald, President Pro Igel e.V.

Preface

Ifrom the Ingolstadt animals’ shelter following an appeal from them. From then the number of hedgehogs I looked after grew from year to year, I set up my rescue cen-

tre. At some point it occurred to me that no one ever brought me very small hedgehogs before the month of August. I puzzled over this “coincidence”. In the 70’s and right into the early 80’s of the last century you could read in all the current hedgehog books that

-

the proviso that a second litter was only possible “under favourable conditions”. These “favourable conditions” seemed very prevalent as there were many so called autumn

any case orphaned hoglets were never brought into my rescue centre before August.This observation made me think. I asked other hedgehog rehabilitators by letter or

friends said that he would get a few very young hoglets brought in at the end of May or beginning of June every year without fail. The man lived about half way between

-vations that hedgehogs only had one litter. He referred to older literature for example J.

hedgehog takes good care of his young/for he goes to the grapevines/pulls the grapes to the ground/rolls on them with his prickly back/sometimes you see him covered in grapes/ so that he looks like a moving bunch of grapes/he carries the grapes to his young on his back impaled on his sharp spines /they eat some of them/ and pick up

the connection between grapes and the rearing of young suggests that the hedgehogs

edition of her standard work had also considered, as well as my own data which agreed with this author, and wrote in that book and in all later editions about only one litter per year.

-

sizes and the breeding season that has ever been carried out. The results are summa-rised in this study.

various hedgehog conservation societies for their cooperation and for the large number

hedgehog friends who gave their time to collect these data.

for uploading it onto the internet as well as for publishing this study.

the revision and reworking of the current English version.

Lindau, B., Spring 2008 / Autumn 2016

Monika Neumeier

III

Contents

Index of Tables, Figures and Diagrams ......................................................................................................... V

1 Introduction .......................................................................................................................... 1

2 Material and Methods .......................................................................................... 5

3 Results of the Analysis and Discussion ..............................................11

3.1 Litter Sizes ...................................................................................................................... 11

3.2 Breeding Seasons ....................................................................................................

3.2.1 Region 1 – Lake Constance/Westallgaeu .................................................. 20

......................................... 21

3.2.3 Region 2 – Southern Bavaria ......................................................................... 21

3.2.4 Region 3 – Northern Baden-Wuerttemberg ........................................... 22

3.2.5 Region 4 – Rhine Plateau and surrounding area .................................. 23

3.2.6 Region 5 – Ruhr Region and Bergisches Land ....................................... 25

3.2.7 Region 6 – Erzgebirge and Thuringian Forest ....................................... 25

.............................................. 26

.....................................................27

3.2.10 Region 9 – Northern Lower Saxony ........................................................... 27

3.2.11 Region 10 – Schleswig-Holstein/Hamburg ...............................................

4 Conclusion ............................................................................................................................ 29

5 Abstract ................................................................................................................................... 30

6 List of references .......................................................................................................... 31

V

Index of Tables, Figures and Diagrams

TablesTable 1 Comparison of litter sizes in certain European countries ...................................... 3

Table 2 Distribution of amounts of data for litter size and breeding seasons ...............................................................................................

Table 3 Absolute uand percentage number of litters in categories 1 – 3 subdivided according to litter size ...................................................................................... 15

in Germany and 1649 litters (excluding Region 4) ................................................... 15

Table 5 Number of litters according to litter size in 11 regions of Germany and the mid-litter size with and without litters with 2 young ............................ 16

Table 6 Percentages of litters in 11 regions of Germany from the 4th week ................................................................................... 19

Table 7 Lake Constance/Westallgaeu .................................................................................................. 20

........................................................................................... 21

Table 9 Southern Bavaria ..............................................................................................................................22

Table 10 Northern Baden-Wuerttemberg ........................................................................................... 23

Table 11 Rhine Plateau and surrounding area .................................................................................. 24

Table 12 Ruhr Region and Bergisches Land ...................................................................................... 25

Table 13 Erzgebirge and Thuringian Forest ....................................................................................... 26

Table 14 Hanover and surrounding area ............................................................................................. 26

Table 15 Berlin and surrounding area ................................................................................................... 27

Table 16 Northern Lower Saxony ............................................................................................................ 27

Table 17 Schleswig-Holstein/Hamburg .................................................................................................

Figures

Fig. 1 (Translation of) Printed version of the German questionnaire since 2005 ...... 9

Fig. 2 Geographical Map of Germany with the eleven areas under investigation ..... 17

Diagrams

Diagr. 1 Hedgehog litter sizes in Germany ....................................................................................... 11

Diagr. 2 Distribution of Litter Sizes in the Age Groups 1 to 3 ................................................. 13

Diagr. 3 Percentage count of all litters in Germany by week of birth and percentage count of all litters excluding Region 4 .....................................................

1Introduction

1

Morrislitter sizes of the hedgehog (Erinaceus europaeus Linnaeus

1758

prompted a further collection of data in

above mentioned study by Morris, to date --

ter sizes, the breeding season had never been explored. The idea that hedgehogs

propounded. This assumption, widely publicised

in the media, was based to a great extent on a television programme which was broadcast in September 1971. At that time,

-pealed to the viewers to help these ”se-cond litters of hedgehogs“ in the autumn, because these young animals would have no chance of surviving the winter. He supported this theory with the help of

litter was produced at the end of May and a further litter at the end of August. Poduschka s assumption presumably re-sulted from observations in Vienna where

warmest regions of Austria with a long growing season. The climatic conditions there contribute to a prolonged mating

later observed in Denmark that only one

even though the Danish climate was ge-

Europe the breeding season lasted the en-

climate. He remarked that most authors who assumed there were two litters a year

because pregnant or lactating females had been found in early and late summer and also in autumn. Herter put forward the possibility of two litters by citing the example of a female who gave birth at the end of June and also in the middle of Au-gust, but pointed out that she had been in

shortly after birth.

given birth to a second litter. They mated from the beginning /middle of May up to

-

itself primarily in an area of warm, moist

Therefore, the climate is milder than the northern latitude of 47° actually suggests.

that the breeding season of two months in Sweden was considerably shorter than

Introduction1Ch

apte

r

2 Introduction

1

only one litter per year was possible.-

centrated his studies on the breeding season. He determined that the hedgehog in Denmark produced its litters between the end of July and the beginning of Sep-

a maximum of 14 days old, 78 young were born in the month of August. He conclu-ded that in Denmark, hedgehogs can only raise one litter per year.

the hedgehog in Europe is summarised in Table 1.

This study will provide information on

In addition, the breeding season in ele-

be addressed as to whether only one lit-

two litters are possible.

3Introduction

1

Country Anzahl der Würfe Altersangabe Wurfgröße Quelle

Britain 70 early young*1late young*

43 with mother* 3,65 30 early young 4,37

Morris (1977) 14 late young 3,71 29 with mother 3,72 53 prenatal 4,57 Morris (1961)

Jersey 9 early young 3,40 2

2 late young 4,00

Netherlands 20 early young 4,15 3 23 late young 4,34

5 with mother 3,60

Germany early young 5,05 4140 late young

44 with mother 4,50unknown prenatal 5,20

Heyne et. al. (1996)dependent nestlings 4,00

Schwitzerland 67 none 4,00–5,00 Lienhardt (1979)

Denmark 453 concerning age 4,33–4,93

Sweden 3–6 weeks old 5,20

Norway 1 early young unknown 5 16 late young 4,13

71 with mother 3,70

1 Data collected by Pat Morris, Britain, and hedgehog carers, especially Kay Bullen2 Data collected by Dru Burdon, Jersey3 Data collected by Marcel Huijser, Netherlands, and hedgehog carers4 Data collected by Monika Neumeier, Germany, and hedgehog carers/rescue centres5 Data collected by Beate Johansen, Norway

* In the data collection initiated by Morris (Footnotes 1-5) the age of the hedgehogs was requested as follows: 1. Were they „early young“, blind/with eyes closed, pink and with white spines?

Table 1: Comparison of litter sizes in certain European countries

4 Introduction

1

5Material and Methods

2

Material and Methods2K

API

TEL

I -nated by Morris regarding hedgehog litters was sent out by the society “Pro

hedgehog rescue centres. Additionally, a

-

categories the observed or found hoglets belonged to.

Morris set out the following categories

1. „very young“ (blind/with closed eyes,

2. „older young“ (with open eyes, darker

3. „with mother“ (active at night outside

The observation date, the observation site and the number of young were also

were to be included in the count.

was included with the annual reports to the various rescue centres. In 2000 there

From 2001 onwards, the association Pro

its website, since 2008 there have been both printed and online versions.

-

precisely (see Figure 1, Page 91, “very young“, only young hedgehogs

“outside, with or without Mother“ were to be included. Additionally, respondents were asked to note the highest and lowest weight of hedgehogs in each litter. These weight tables were intended to help cor-rect any errors in the choice of category during data analysis. During part of the

also contained an option as to whether the young were seen with or without the mother, or if they were brought to a rescue centre with or without the mother.

participants were experienced hedgehog carers, usually managers of rescue cen-

-ly and over prolonged periods concerned themselves with hedgehogs in distress. The respondents who completed the

regarded as knowledgeable about hedge-hogs. Experienced rehabilitators or rescue centres ensure that the hoglets really are

in cases where this is not clear, take steps to try to reunite the young with their mo-ther. This can be successful when a mater-nity nest is disturbed whilst clearing up or gardening, the mother leaves the nest

6 Material and Methods

2

If very small hoglets are found outside the nest, then they are clearly orphaned, the mother is no longer in a position to look after her babies. A short digressi-

suckled by their mother until about the 24th day after their birth, up to this time they are nestlings. Their eyes and ears

erupt. In the following days they start to explore outside the nest and to forage for food (hedgehog prey is predominantly nocturnal, which is one of the reasons

The mother does not help the young to fo-rage, she searches for her insect prey over a much larger area as her need for food is

-ring lactation. A female hedgehog in cap-tivity suckling seven hoglets needs twice as much food as an adult on its own whe-re the aim is to achieve a gain in weight. This large ration will not result in any weight gain in the lactating female.

the nest at about three and a half weeks old, they must learn for themselves how to pull earthworms out of the ground or how to overpower a beetle. They could not survive on these initial slim pickings, so during the day they are still suckled by mother. As they get older, so their skills at hunting for insects and worms impro-ve and gradually they need less of their

of age the young are able to feed themsel-ves independently.

can assume that there is no mother in the

nest, that she is either sick or does not have enough milk. The young are in need of help. Hoglets which are still nestlings only crawl out of the nest if they are left

their mother, who in such cases is almost always dead, fatally ill or badly injured, which is why animal lovers rightly take in these orphans. Most hoglets, especially the very small ones found out of the nest

--

onnaires, for example if the mother was injured or sick. The error rate in this cate-gory was therefore assessed as very low.

the wild when human help did not seem necessary and no action was taken were only recorded by a very small number of respondents.

the breeding season, from 2000 onwards when one very small hoglet was found

-naire, because “singletons” represent an entire litter, the size of which is, of course,

hedgehogs could not be used to determi-ne litter size, the amounts of data for birth dates and litter sizes vary in the analysis.

Many participants took the trouble to refer to their own, older records so that data from a period of 23 years (from 1983

The distribution over time is shown in Table 2.

-dividually, i.e., the date of birth of each litter was calculated from the observation

days were subtracted from the observa-


2

were subtracted. Therefore, this approach always assumed the maximum age of a litter at the time it was found. The age of orphaned litters brought into the hedge-hog rescue centres is easily underestima-ted, because the young have often been without food for several days and are dehydrated, so their weight does not cor-respond to their body length or stage of development.

If the weights of the lightest and hea-viest hoglet in a litter on the observation

additional information allowed a more exact calculation of the “deduction” (the

-

20g hoglet cannot be one week old, it can only be one or two days old. To determi-ne the date of birth the deduction for the relevant age group was not used but with this additional information a more pre-cise calculation was possible.

Database and then processed and ana--

ters and computer operations.

To minimise errors, the author who has decades of experience with hedgehogs of

-naires herself (various analysts would

addition she knew many of the respon-dents personally so knew who might have over or under estimated the age of the hoglets.

The calculated “dates of birth” were

The location where each individual lit--

many (Figure 2, Page 17hedgehogs were found formed clusters which were grouped into eleven regions. This division of regions, of course, took no account of the overall hedgehog popu-

on the participation levels of respondents

hedgehog rescue centres in the city and surrounding area reminded its rescue

repeatedly.

Material and Methods

2

Table 2: Distribution of amounts of data for litter size and breeding seasons in Germany from 1983 - 2005

YearNumber of Data

YearNumber of Data

Litter size Breedingseason Litter size Breeding

season1983 1 2 1995 32 391984 17 1996 106 1161985 16 1997 761986 10 15 1998 46 571987 15 15 1999 121 1351988 13 17 2000 1371989 12 16 20011990 12 2002 225 2931991 15 22 20031992 9 2004 771993 12 16 2005 751994 23 33

total of all years 1437 1817


2

Figure 1: (Translation of) Printed version of the German questionnaire since 2005

Pro Igel – Association for Integrated Conservation in Germany

Questionnaire on Hedgehog Litter Sizes and Breeding Seasons

If you see baby hedgehogs or a mother hedgehog with her young, or if hoglets with or without their mother are brought into your rescue centre, please complete this questionnaire. Please copy this sheet and use a separate questionnaire for each litter. 1 How many young were in the litter

(including any dead babies) 2. If known, please give the lowest and highest weight in the litter when found

Were the young “very young”? With shut eyes, pink and with white spines? (1 week old or younger)

OR “older young”? Dark skin colour, brown spines, Maybe furry tummies, no teeth

(older than one week, younger than 3 weeks)

OR “independent young” able to eat for themselves”? (older than 3 weeks, younger than 5 weeks, with teeth)

3. When were the hoglets found/first seen (date)?

4. Where were the hoglets seen/found (post-

code and town)? 5. Address of respondent: name surname phone street number fax postcode place Email

very young

older

independent

number

day month year

(mark with a cross weight from - to

10 Material and Methods

2

11Results of the Analysis and Discussion

3

Results of the Analysis and Discussion3Chap

ter

3.1 Litter sizes

To determine litter sizes, a total of 1437 -

Diagram 1 shows how many hedgehogs were in each litter. The litter sizes are separated into 3 age groups in Diagram 2. Table 3 gives information as to the absolute number of litters, as well

as the percentage in each category, sub-divided according to litter size.

Figure 2and extent of the eleven selected regions

-ven regions are numbered from 1 respec-tively 1a to 10, from south to north.

In Table 5 --

could not be assigned to a region. The ave-rage litter sizes from all areas are shown also in Table 5.

Diagramm 1: Hedgehog litter sizes in Germany (n = 1437)

On average a litter contained 4.43 young ± 1,67 (standard-deviation).

Num

ber o

f lit

ters

Litter sizes

12 Results of the Analysis and Discussion

3

The majority of litters contained four -

7 or more young, however, one litter of 11 young was registered. The average litter

The average range of litter size was 3 (pre-

-

this be?

The hoglets were not all born with the same weight, from the start there were lighter and heavier, weaker and stronger

-ceived more of their mother’s milk, and so were better developed than their weaker siblings. Sometimes several would die in the nest or were later at a disadvantage when foraging due to their weaker con-stitutions. Accidents, lack of resistance to disease and a heavier parasite burden can take young hedgehogs’ lives and decima-

-ty in juvenile hedgehogs up to the end of

size of 4.37 for “very young“ hedgehogs (newly born with eyes and ears closed

-

a perinatal (just before, during and just

increased the calculated litter size in this

-ny. This correlates with the research of

-bryos or uterine scars in hedgehogs in the

-

hoglets.This study cannot contribute anything

-cause the responding hedgehog rehabi-litators hand reared the majority of the often just days-old, sick, undernourished

-on a large number of the recorded litters


3

Diagram 2: Distribution of Litter Sizes in the Age Groups 1 to 3 (n=1437)

Perc

enta

nges

Litter sizes

The average size of litters up to one week of age was 4.76 ± 1.69 (standard deviation), for litters bet-ween 1-3 weeks of age 4.41 ± 1.67 (standard deviation), and for litters between 3 -5 weeks of age 4.24 ± 1.63 (standard deviation).

the opinion that in areas where hedge-hogs can produce two litters a year, the phenotype (= the appearance of an or-ganism formed by inheritance and envi-

areas with a shorter breeding season, the phenotype of larger litters would be more successful. If one considers the ave-

surrounding area (Table 5

is so prolonged that two litters are at all possible - the average here is 4.20 young,


3 event the average litter sizes in some areas with a shorter breeding season are

There is a large element of uncertainty

the reports of litters with only two young.

a discovery of only two young was often not considered a „litter“, and was therefo-

the hedgehog carers or managers of res-cue centres participating in this study, several participants within an area repor-ted a high percentage of litters with two young, others fewer. Thus, for example,

--

-

in the number of twin births throughout

rule out this possible source of error, lit-

ters with 2 young were excluded from the calculations to reveal how the average lit-

litter size of 4.42 hedgehogs was calcula-

-

4.38 young per litter (excluding twin bir-

-ny when litters with twins were included

with twins were excluded. This means

-


3

Table 3: Absolute and percentage number of litters in categories 1-3 subdivided according to litter size

Litter size

Category 1 up to 1 week

Category 2 1 – 3 weeks

Category 3 3 – 5 weeks All Categories

abs. % from n = 335 abs. % from

n = 630 abs. % fromn = 308 abs. (% from

n = 1437)

2 31 9,25 13,97 17,16 200 13,92 3 47 14,03 111 17,62 94 19,92 252 17,544 74 22,09 152 24,13 93 19,70 319 22,205 25,37 97 20,55 300 6 50 14,93 95 70 215 14,967 26 7,76 35 5,56 22 4,668 15 24 11 2,33 509 4 1,19 4 0,63 3 0,64 11 0,7710 2 0,60 3 1 0,21 6 0,4211 1 0,30 – – – – 1 0,07

Totals 335 1437

--

mark. He investigated primarily litters in the nest, not litters which had been taken

litters recorded. This is an indication that litters with 2 young were much more pre-

Further research is needed, in particular -

ber of litters per year and the resultant

which appears repeatedly in this study is a measure of “variance” or the average

deviation of a random variable from the mean. The more data are available and the closer these data points fall with little variance, the lower the standard devia-tion will be. The calculated value for the

-

Table 4: Monthly distribution in percentage terms of 1817 litters (all regions) in Germany and 1649 litters (excluding Region 4 – Rhine Plateau and surrounding areas)

April May June July Aug. Sept. Okt.All Regions (n = 1817) 1 20 121 997 554 40All Regions (% from 1817) 0,06 1,10 4,62 6,66 54,90 30,50 2,20Excl. Region 4 (n = 1649) 0 2 3 97 971 539 37Excl. Region 4 (% from 1649) 0 0,12 32,70 2,24


3

Tabl

e 5:

N

umbe

r of l

itter

s acc

ordi

ng to

litt

er si

ze in

11 re

gion

s of G

erm

any

and

the

mid

-litt

er si

ze w

ith a

nd w

ithou

t litt

ers w

ith 2

you

ng a

nd w

ith a

nd

w

ithou

t Re

gion

4 (R

hein

Pla

teau

and

surr

ound

ing

area

)

Regi

on

Litt

er s

izes

Tota

l lit

ters

(N

umbe

r of

youn

g)

Mea

n

litte

r siz

e±

stan

dard

de

viat

ion

Mea

n

litte

r siz

ew

itho

ut li

tter

s w

ith

2 yo

ung

± st

anda

rd

devi

atio

n

23

45

67

89

1011

1 –

Lak

e Co

nsta

nce/

Wes

tallg

aeu

1315

1411

67

22

--

7

0 (3

01)

1a

– La

ke C

onst

ance

/Obe

rsch

wab

en7

1313

93

31

--

-

49

(197

)4,

02 ±

1,46

4,45

± 1,

31

2 –

Sou

ther

n Ba

vari

a 3

322

3119

159

31

-

3 –

Nor

ther

n B

aden

-Wue

rtte

mbe

rg

1927

196

5-

1-

113

(497

)4,

40 ±

1,73

4 –

Rhi

ne P

late

au a

. sur

roun

ding

are

a11

2740

103

1-

--

120

(504

)4,

20 ±

1,26

4,42

± 1,

09

5 –

Ruh

r Reg

ion/

Berg

isch

es L

and

1461

7449

269

3-

1-

23

7 (1

005)

4,24

± 1,

33

6 –

Erz

gebi

rge/

Thur

ingi

an F

ores

t5

37

43

41

-

53

(293

)5,

53 ±

1,94

5,90

± 2

,24

7 –

Han

over

and

sur

roun

ding

are

a2

1015

1715

32

--

-

64

(306

)

8 –

Ber

lin a

nd s

urro

undi

ng a

rea

5445

4737

99

-1

13,

91 ±

1,76

4,70

± 1,

50

9 –

Nor

ther

n Lo

wer

Sax

ony

24

1411

51

--

-

10 –

Sch

lesw

ig-H

olst

ein/

Ham

burg

3435

4240

4112

52

--

211

(929

)4,

40 ±

1,66

719

137

9-

1-

5,33

± 1,

59

Tota

l/Ave

rage

200

252

319

300

215

5011

61

1437

(637

3)4,

43 ±

1,67

Tota

l/Ave

rage

exc

l. Re

gion

4

Rhin

e Pl

atea

u an

d su

rrou

ndin

g ar

ea22

529

126

020

549

116

14,

46 ±

1,71


3

Figure 2: Geographical Map of Germany with the eleven areas under investigation

Iller

Iller

rellI

I lle r

I s ar

I sar

I sar

Isar

Isar

K inzig

Kinzig

Kinzig

Regen

Regen

Regen

Regen

Unstrut

Unst rut

Uns trut

Fulda

Fulda

Fulda

Fulda

Jagst Jagst

Jags t

Naab

Naa

b

Naab

Naa

b

S ieg

Sieg

S ieg

E nz

Enz

Enz

S chwarze Els t er

Schwarze Elster

Schwarz e Elster

Ahr

Ahr

Altmühl

A ltmühl

Altmühl

Eder

Eder

Eder

Saar

Saar

Rot er Main

Neiße

Neiße

Mit tellandkanal

Mittellandkanal

Mittellandkanal

Mittellandkanal

Mittellandkanal

Weiße Elster

Weiße Elst er

Weiße E lster

Weiße E

lster

Lech

Lec h

Lech

Elde

Elde

Elde

E lde

Weißer Main

Uec

ker

Ueck

er

Trave

Trave

Kocher

K ocher

K ocher

Diemel

Diemel

Diemel

Inn

I nn

Inn

Inn

Hunte

Hunte

Hunte

Hunte

Ostpeene

Elbe-Havel-Kanal

Elbe-Se itenk anal

Elbe-Seitenkanal

Saale

Saale

Saale

Saale

Saale

Saale

Saale

Rhein-Herne-Kanal

E ider

Eider

Eider

Aller

Aller

A lle r

Aller

Hase

Hase

H ase

Has e

Rur

Rur

Rur

Brigach

Nahe

Nahe

LippeLippe

Lippe

Kyll

Kyll

Kyll

K yll

Main-Donau-K anal

M ain-Donau-K anal

Main- Donau-Kanal

Lahn

Lahn

Lahn

Lahn

Lahn

Warnow

Warnow

Warnow

Havel

Havel

Havel

Havel

Havel

Spree

Spree

Spree

Spree

Spree

Spree

Oste

Oste

Os te

Teterower Peene

Dortmund-Em s-Kanal

Dortm

und-Ems -Kanal

lana

K-s

mE-

dnu

mtro

D

Ruhr

Ruhr

Ruhr

Peene

Erf t

Erf t

Erf t

Br eg

B reg

Mulde

Mulde

edluM

Muld

e

Mulde

Leine

Leine

Leine

Leine

Wer

ra

Werra

Werr a

Werra

MainMain Ma

in

Main

Elbe

Elbe

Elbe

Elbe

Elbe

Elbe

Elbe

Westoder

Donau

Donau

Donau

Donau

Donau

Süderelbe

Norderelbe

Mosel

Mosel

Mosel

Ems

Ems

Ems

Ems

Rhein

Rhein

Rhein

Rhein

Rhein

Rhein

Rhein

Nord-Ostsee-Kanal

Weser

Weser

Weser

Weser

Oder

Neckar

Neckar

Walchen-see

Selenter See

Müritz

Schwe-rinerSee

SteinhuderMeer

Eider

Chiemsee

Bodensee

Tegernsee

Forg

gens

ee

Dümmer

Kum

merow

er Se

e

Simss

ee

Geiseltalsee

PlauerSee

Ammer-see

Schaal see

GroßerPlöner See

Malc

hiner

See

Tolle

nses

ee

Star

nber

ger S

ee

Darmstadt

Erlangen

Osnabrück

Frankfurt

Dresden

Bremen

Karlsruhe

Potsdam

Paderborn

HalleEssen

Wolfsburg

Bonn

Lübeck

Hamburg

Saarbrücken

Oldenburg

Mannheim

Braunschweig

DüsseldorfWuppertal

Koblenz

Ingolstadt

Rostock

Würzburg

Münster

Berlin

Wiesbaden

Ludwigshafen

Nürnberg

Siegen

Magdeburg

Reutlingen

Hannover

ErfurtChemnitz

Bielefeld

Kassel

Augsburg

HeidelbergFürth

Bremerhaven

Ulm

Jena

Göttingen

Pforzheim

Köln

BochumDuis-burg

Kiel

München

Leipzig

Trier

Dortmund

Stuttgart

Mainz

Regensburg

Freiburg

Aachen

Heilbronn

1a

2

3

4

5

6

78

9

10

OstseeNordsee

4

4

1 Lake Constance/Westallgaeu

1a Lake Constance/Oberschwaben

2 Southern Bavaria

3 Northern Baden-Wuerttemberg

4 Rhine Plateau and surrounding area

5 Ruhrgebiet/Bergisches Land

6 Erzgebirge/Thuringian Forest

7 Hanover and surrounding area

8 Berlin and surrounding area

9 Northern Lower Saxony

10 Schleswig-Holstein/Hamburg

Designation of the eleven marked regions on the map:

Map created with EasyMap© Lutum+Tappert, Bonn

Ravensburg

Lindau 1

Results of the Analysis and Discussion

3

3.2 Breeding Seasons

For the evaluation of the breeding season,

-many is shown in percentage terms in Diagram 3last week of April, and the last two lit-

green bars in Diagram 3 --

May to the third week of June only a few hedgehogs are born, the actual breeding

in the last week of July (lime green bars in

-

Diagram 3: Percentage count of all litters in Germany by week of birth (n = 1837) and percentage count of all litters excluding Region 4 - Rhine Plateau and surrounding area (n = 1649)

Weeks of birth

shows the week of birth of each litter in the eleven selected regions on the map in Figure 2 (Page 17 -corporate a total of 1727 litter sites, a total

which could not be allocated to a particu-

Table 4 shows the percentage distributi--

tober. All eleven regions are listed separa-tely in Table 6 and Figure 2 (Page 17 .

regions will be investigated individually from South to North.


3

Tabl

e 6:

Pe

rcen

tage

s of l

itter

s in

11 re

gion

s of G

erm

any

from

the

4th

wee

k of

Apr

il to

the

4th

wee

k of

Oct

ober

*

The

perc

enta

ges f

or a

regi

on a

re d

epen

dent

on

the

tota

l num

ber o

f litt

ers w

ithin

this

are

a; th

e pe

rcen

tage

s of t

he to

tal f

or a

ll re

gion

s with

the

„Res

t“

Regi

onN

o. o

f lit

ters

Perc

enta

ges

of li

tter

s pe

r wee

k (4

th w

eek

of A

pril

to 4

th w

eek

of J

uly)

4. A

1. M

2. M

3. M

4. M

1. J

2. J

3. J

4. J

1. J

2. J

3. J

4. J

1 –

Lak

e Co

nsta

nce/

Wes

tallg

aeu

2,5

1a

– La

ke C

onst

ance

/Obe

rsch

wab

en75

1,33

12,0

2 –

Sou

ther

n Ba

vari

a 11

31,7

7 3

– N

orth

ern

Bade

n-W

uert

tem

berg

21

60,

460,

465,

05 4

– R

hine

Pla

teau

+ s

urro

undi

ng a

rea

0,6

1,79

1,79

1,19

5,95

16,6

76,

550,

64,

76 5

– R

uhr R

egio

n/Be

rgis

ches

Lan

d 25

90,

390,

390,

390,

394,

63 6

– E

rzge

birg

e/Th

urin

gian

For

est

561,7

95,

36 7

– H

anov

er +

sur

roun

ding

are

a

73 8

– B

erlin

+ s

urro

undi

ng a

rea

312

0,32

0,32

1,60,

640,

96 9

– N

orth

ern

Low

er S

axon

y 46

10 –

Sch

lesw

ig-H

olst

ein/

Ham

burg

32

70,

312,

453,

0690

1,11

1,11

6,67

Tota

ls o

f Reg

ions

incl

. „Re

st“

0,06

0,17

0,17

0,11

0,66

1,43

1,60,

770,

770,

551,1

6

Regi

onN

o. o

f lit

ters

Perc

enta

ges

of li

tter

s pe

r wee

k (1

st w

eek

of A

ugus

t to

4th

wee

k of

Oct

ober

)

1. A

2. A

3. A

4. A

1. S

2. S

3. S

4. S

1. O

2. O

3. O

4. O

1 –

Lak

e Co

nsta

nce/

Wes

tallg

aeu

7,5

22,5

12,5

23,7

520

,02,

5 1

a –

Lake

Con

stan

ce/O

bers

chw

aben

7517

,33

14,6

712

,09,

3312

2,67

6,67

4,0

5,33

2,67

2 –

Sou

ther

n Ba

vari

a11

314

,1625

,66

15,0

46,

191,7

7 3

– N

orth

ern

Bade

n-W

uert

tem

berg

216

4,13

19,2

722

,94

21,5

611

,93

9,63

2,75

0,46

4 –

Rhi

ne P

late

au +

sur

roun

ding

are

a 9,

2716

,22

15,4

411

,97

15,0

69,

274,

252,

71,1

60,

39 5

– R

uhr R

egio

n/Be

rgis

ches

Lan

d25

97,

3514

,71

16,9

113

,24

16,9

15,

152,

944,

412,

21 6

– E

rzge

birg

e/Th

urin

gian

For

est

565,

3621

,43

14,2

91,7

95,

363,

573,

57 7

– H

anov

er +

sur

roun

ding

are

a73

20,5

531

,51

12,3

39,

592,

74 8

– B

erlin

+ s

urro

undi

ng a

rea

312

5,77

10,2

619

,55

16,3

515

,06

6,73

0,96

9 –

Nor

ther

n Lo

wer

Sax

ony

466,

526,

5236

,96

19,5

713

,04

4,35

2,17

10 –

Sch

lesw

ig-H

olst

ein/

Ham

burg

327

13,7

616

,21

16,5

17,

033,

671,5

30,

3190

15,5

612

,22

5,56

5,56

5,56

1,11

1,11

Tota

ls o

f Reg

ions

incl

. „Re

st“

7,71

13,6

516

,24

12,4

99,

195,

453,

361,3

20,

720,

060,

11


3

3.2.1 REGION 1 – Lake Constance/ Westallgaeu

This region is in the foothills of the Alps. There is considerable rainfall and the gro-

months in which the average temperature

-vel, are generally cold with considerable

-

milder, with little snow during the win-ter. However, in the research region this

the mating or breeding season.

of all hedgehogs were born from the se-

September. If one assumes a minimum of

and an average of 42 days for lactation, 11 weeks are needed from conception to

litters each in the fourth week of July and the fourth week of September, all hedge-

weeks. Here, a second litter is completely impossible.

.

Table 7: Lake Constance/Westallgaeu (n = 80)

Month July August September

Week

4. W

eek

1. W

eek

2. W

eek

3. W

eek

4. W

eek

1. W

eek

2. W

eek

3. W

eek

4. W

eek

Number of litters 2 6 10 19 16 7 0 2

Number of littersin the month 2 53 25


3

3.2.2 REGION 1a – Lake Constance/ Oberschwaben

-schwaben also lies in the foothills of the

and a moderate amount of rain characte-

-

tance and is not noted for such a great dif-ference in altitude. The breeding season is somewhat earlier, the main breeding season lasts from the last week in July to

A second litter here would be something of a rarity.

Table 8: Lake Constace/Oberschwaben (n = 75)

Month July Aug. Sept. Oct.

Week

3. W

eek

4. W

eek

1. W

eek

2. W

eek

3. W

eek

4. W

eek

1. W

eek

2.W

eek

3. W

eek

4. W

eek

1. W

eek

2. W

eek

Number of litters 1 9 13 11 9 7 9 2 5 3 4 2

Number of litters in the month

10 40 19 6

3.2.3 REGION 2 – Southern Bavaria

In this region which also lies in the foothills of the Alps, there is average rainfall, with the exception of the Danube Valley where it rains slightly more. The growing season

Even though two litters were seen in the

of all hedgehogs are born in the month of

at the beginning of July would be able to

the litters born at the beginning of July and three litters born in the fourth week of Sep-

-hogs were all born within seven weeks. Similarly, no second litter can be produced

.


3

Table 9: Southern Bavaria (n = 113)

Month July Aug. Sept. Oct.

Week1.

Wee

k

2. W

eek

3. W

eek

4. W

eek

1. W

eek

2. W

eek

3. W

eek

4. W

eek

1. W

eek

2. W

eek

3. W

eek

4. W

eek

1. W

eek

Number of litters 2 0 0 10 16 29 21 17 7 0 1 2


12 16 2

3.2.4 REGION 3 – Northern Baden- Wuerttemberg

The central point of this region, the city of Stuttgart, lies on the river Neckar. Along this river the growing season can last for six months, but in most of the region stu-

-mate is rather dry.

The breeding season begins in the fourth week of July and continues for

are born between the second and fourth

only one was born so early that the mo-ther could have had a chance to mate suc-cessfully for a second time.

Here, as in a few other cases, when a litter is so extremely early and so far ahead of the other births in the region the suspicion is raised that mating occurred while the hedgehogs were kept together

well after hibernation, whilst their cou-sins who have overwintered in the wild

spring and regain their strength slow-

breeding condition much sooner than malnourished ones.

In total 4 litters were born in the fourth week of September to the second week in


3

3.2.5 REGION 4 – Rhine Plateau and surrounding area

the rivers Mosel, Nahe, Main and Neckar

-den on the Swiss border. In large parts of this region the growing season lasts for six or even seven months and in general there is very little rainfall.

Here, the breeding season follows a

registered from the fourth week of April. The main breeding season begins in the

litters were born during this six week pe-riod.

In the southern part of The Nether--

breeding season began in the third week of May and lasted until the fourth week

-

preconditions for two litters per year. A

months. There were litters recorded up to

-ter could become independent. So these litters must have been conceived in the third week of June at the latest. In any

the second week of July that they could

Table 10: Northern Baden-Wuerttemberg (n = 218)

Month June July August September October

Week

2. W

eek

3. W

eek

4. W

eek

1. W

eek

2. W

eek

3. W

eek

4. W

eek

1. W

eek

2. W

eek

3. W

eek

4. W

eek

1. W

eek

2. W

eek

3. W

eek

4. W

eek

1. W

eek

2. W

eek

Number of litters

1 0 0 0 0 1 11 9 42 50 47 26 21 6 3 0 1


1 12 56 1


3

It was not possible within the scope of this study to clarify whether a small per-

give birth twice a year. Further research is necessary to establish this.

-

gave birth from the beginning of May to the beginning of August, and noted two

back into season/oestrus either after suc-cessful breeding or after the loss of a litter.It can be concluded from Table 5, that on

--

-ters were to be expected in warmer areas, because hedgehogs in these areas would

size - in relationship to other areas - really lead to the conclusion, that a second litter

-teau? This result can also lead to a com-

Particularly in warmer regions with mild

surrounding area, young hedgehogs have a better chance of reaching adulthood be-cause a longer growing season reduces the mortality rate (caused both by the harsh-

In order to maintain the species a second litter would be less necessary and also make less sense here than in regions with a less favourable climate. Pregnancy, birth and lactation present health risks for a fe-

persist in which life expectancy is redu-ced by giving birth more often? It is con-ceivable that in such good living condi-

even if litters are smaller than in regions with a less favourable climate.

Table 11: Rhine Plateau and surrounding area (n = 168)

Month

Apr

il

May June July August September Oct.

Week

4. W

eek

1. W

eek

2. W

eek

3. W

eek

4. W

eek

1. W

eek

2. W

eek

3. W

eek

4. W

eek

1. W

eek

2. W

eek

3. W

eek

4. W

eek

1. W

eek

2. W

eek

3. W

eek

4. W

eek

1. W

eek

2. W

eek

3. W

eek

4. W

eek

1. W

eek

2. W

oche

Number of litters 1 3 3 2 10 14 25 14 11 1 4 6 4 6 10 6 6 3 0 1 2


1 24 26 15 3


3

3.2.6 REGION 5 – Ruhr Region and Bergisches Land

-

but summers often relatively cool. In this

months, and the breeding season begins in the fourth week of July and continues well into September. Most hedgehogs are born between the beginning of August and the

-ding season of 14 weeks is very long (from the second week of July to the third week

possible strictly from the calculations.

June. After that, litters were not born until the second week of July. In these and the cases of very early litters reported from other regions there must be a suspicion that very early matings could have oc-curred in captivity (animals previously in need of care maybe were not kept separa-tely but in groups after hibernation until release, which is contrary to their natural

-

were therefore ready to conceive soon after

Table 12: Ruhr Region and Bergisches Land (n = 259)

Month May June July August September October

Week

4. W

eek

1. W

eek

2. W

eek

3. W

eek

4. W

eek

1. W

eek

2. W

eek

3. W

eek

4. W

eek

1. W

eek

2. W

eek

3. W

eek

4. W

eek

1. W

eek

2. W

eek

3. W

eek

4. W

eek

1. W

eek

2. W

eek

3. W

eek

Number of litters 1 1 0 0 0 0 1 1 12 24 21 42 40 31 39 24 11 7 3 1


1 1 14 127 105 11

3.2.7 REGION 6 – Erzgebirge and Thuringian Forest

The locations of the reported litters are predominantly in the foothills of both of these lower mountain ranges in an area

average annual rainfall. The winters are -

tumn, it can be rather cool.

The main breeding season begins in the second week and ends in the fourth week of August. In these three weeks,

breeding season lasts for nine weeks from the fourth week of July to the fourth week of September, second litters would not be

second week of July and two litters as late


3

Month July August September October

Week

2. W

eek

3. W

eek

4. W

eek

1. W

eek

2. W

eek

3. W

eek

4. W

eek

1. W

eek

2. W

eek

3. W

eek

4. W

eek

1. W

eek

2. W

eek

3. W

eek

4. W

eek

Number of litters 1 0 3 3 12 16 1 5 3 2 0 0 0 2


4 39 11 2

Table 13: Erzgebirge and Thuringian Forest (n = 56)

3.2.8 REGION 7 – Hanover and surrounding area

This region lies in an area with rather low

ends in the third week of September, and is therefore eight weeks long. The main breeding season lasts for three weeks from the second to the fourth week of August in

-tered. The possibility of two litters can be completely ruled out here.

Month July August September

Week

4. W

eek

1. W

eek

2. W

eek

3. W

eek

4. W

eek

1. W

eek

2. W

eek

3. W

eek

Number of litters 6 15 23 9 7 5 2


6 53 14

Table 14: Hanover and surrounding area (n = 73)


3

3.2.9 GEBIET 8 – Berlin and surrounding area

The breeding season begins in the month of August and lasts until the end

Table 15: Berlin and surrounding area (n = 312)

Month June July August September October

Week

3. W

eek

4. W

eek

1. W

eek

2. W

eek

3. W

eek

4. W

eek

1. W

eek

2. W

eek

3. W

eek

4. W

eek

1. W

eek

2. W

eek

3. W

eek

4. W

eek

1. W

eek

2. W

eek

Number of litters

1 0 1 5 2 3 32 61 51 47 37 26 21 4 3


1 11 162 131 7

Month August September

Week

1. W

eek

2. W

eek

3. W

eek

4. W

eek

1. W

eek

2. W

eek

3. W

eek

4. W

eek

Number of litters 3 3 17 9 5 6 2 1


32 14

3.2.10 GEBIET 9 – Northern Lower Saxony

This region borders on the North Sea. It includes the county of East Frisia up to

a maritime climate with mild winters. De-spite a very changeable climate, the area has relatively low rainfall. Here again the

The breeding season starts at the begin-ning of August and lasts until the end of September. This time period is too short to allow the possibility of a second litter. Two litters were reported in the third week and one in the fourth week of September. The main breeding season extends from the third week of August to the second week of September, whereby more than half

third and fourth week of August. Table 16: Northern Lower Saxony (n = 46)

a chance to mate a second time after the

a second time not later than the second

Results of the Analysis and Discussion

3

3.2.11 REGION 10 – Schleswig-Holstein/ Hamburg

This region encompasses the entire area of the Federal state with the same name, Schleswig-Holstein, which borders on Denmark, as well as on the city-state of Hamburg, which lies on the river Elbe. The climate is similar to that of Northern

there is more rainfall than on the coast in

The breeding season begins in the second week of July and ends after the

-

of September, a period of around four weeks. The six latest litters were born in

-on 10, second litters are not possible.

Month July August September October

Week

2. W

eek

3. W

eek

4. W

eek

1. W

eek

2. W

eek

3. W

eek

4. W

eek

1. W

eek

2. W

eek

3. W

eek

4. W

eek

1. W

eek

2. W

eek

Number of litters 1 10 45 53 54 60 27 23 12 5 1


19 122 6

Table 17: Schleswig-Holstein/Hamburg (n = 327)

29Conclusion

4

The examination of the eleven regi-ons shows that only in one region

-rounding area which also incorporates

purely in terms of the time available are

they actually occur must be the subject of

as to how much so-called replacement lit-ters contribute to reproduction. It cannot be ruled out that some particularly late litters may indeed be these replacement

shortly after birth, a female possibly has the opportunity to mate a second time

would survive in the wild if her young die of some illness, he assumes that the illness or for example poisoning would be

assumption is correct or not needs further research. There are other events which can kill an entire litter apart from illness, for example when a dog raids a nest, or if a nest is destroyed by gardening or cons-

-

An argument against the probability of a larger number of replacement litters is also the fact that the female hedgehog is not ready to mate directly after giving

Table 4 shows clearly that the months of

-ny. If one disregards the litters from the

-

Conclusion4Chap

ter

30 Zusammenfassung

5

Inprimarily targeted at hedgehog rescue centres, a census was taken as to the

size, estimated age, observation date and -

tern European hedgehog (Erinaceus euro-paeus were analysed regarding litter size, and

young. In litters of up to one week of age,

an age of one to three weeks, the average was 4.41 young, and at an age of three to

hedgehogs was determined.1817 observations were used to deter-

mine the length of the breeding season.

the start and length of the breeding season

location and climate of the observation site.

-

young hedgehogs were seen or more spe--

bilitators and rescue centres between the -

vember. The respective dates of birth were calculated from the dates of the observa-tions and other criteria which were set out

-died occurred in the months of August

-teau and some surrounding areas around

-

-

for a second litter. However, even in this region there several reasons why a second litter may not be possible.

KEYWORDS: hedgehog, Erinaceus europaeus, litter size,

second litter

Abstract5Chap

ter

31Anhang

6

List of References (as at 2008)6Chap

ter

-

-

. Dis-

. Unpub- lished.

--

litter sizes and breeding seasons - pro igel - home€¦ · number of hedgehogs i looked after grew...

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