To advance our knowledge about hedgehogs (Erinaceus europaeus Linné 1758) we collect data for research and ask for your support. Thank you for your co-operation in advance!

We like to help as much as we possibly can, so that more knowledge about hedgehogs can be gained through scientific research.

Hedgehog breeding season and litter sizes in Germany
We have collected data since 1996 about hedgehog litters, to begin with we participated in the survey undertaken by English researcher, Pat Morris, into hedgehog litter sizes throughout europe.

Subsequently, data for Germany was collected by Pro Igel, to determine the length of the breeding season and the size of litters. Based on the data collected so far, we have established that 5 is the average litter size and that 80% of hedgehogs in Germany are born between August and September. Only in the warm Rhine valley and Saarland are babies born earlier in the year. Second litters are exceptional.

We continue to collect data: please let us know about hedgehog litters. With regard to the length of the breeding season, we are interested in the dates when even single hoglets are found. Because every single orphaned hoglet comes from an albeit unknown litter in the area. We are only interested in litters where the age of the animals can be ascertained, more or less exactly, in accordance with the questionnaire.

Please support us and complete the (German) Questionnaires. Many thanks for your co-operation!

If you see baby hedgehogs (hoglets) or a mother hedgehog with her young, or if you find orphaned hedgehogs or they are brought into your rescue centre either with or without their mother, please fill in this questionnaire. You will be contributing to the biggest European collection of data on dates of birth and litter sizes in hedgehogs.

This information is vital to enable us to learn more about hedgehog biology and behaviour, and may help us detect the effects of climate change on hedgehog reproduction. Any increase in our knowledge will support hedgehog conservation and protection.

Never disturb a hedgehog nest to obtain information as this might make the mother eat or abandon her young.

Age determination
The appearance of the baby hedgehogs (hoglets) will help you determine their age. See the table below to help you complete the questionnaire. Weights may vary considerably from those given in the table, depending on litter size and nutritional condition. So please give the weight of the smallest and the biggest of the babies and estimate their age primarily from skin colour/spines/fur/eyes/ears/teeth.

AgeSkin colourSpinesFurEyes EarsTeethWeight (g)
At birthpinkwhitenoneshutnone12 – 25
1 weekpinka few darknoneshutnone30 – 50
2 weeksgreydarkbit of fuzzopeningnone60 – 80
3 weeksgreydarkvisible furopenerupting100 – 130
4 weeksgreydarkthick furopenfully erupted140 – 180

© Monika Neumeier

Questionnaire