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Digest 11 September 2000 - Vol. 1, No. 6

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1) Reply (DT 1/5): Bait Tube Surveys (Mike Jordan)

Dear Mike
We have been doing a lot of research on using baited hair tubes for a whole series of small mammals, including Hazel Dormouse (Muscardinus avellanarius), and fairly soon several Graphiurus spp. These can be very successful although the normally low density of Muscardinus means that a lot of tubes are necessary.

However they do represent a survey technique which is a lot less permanent than nest boxes, and not dependent upon the presence of eaten Hazel nuts and hence Hazel.

If you want to contact me I can give you some advice on dimensions, baits etc. that have proved very effective.

Mike Jordan
Animal Management Section
Sparsholt College Hampshire
Hants. SO21 2NF

2) Results from the September 2000 Nestbox-Check in Lithuania (R. Juškaitis)

Dear Werner,
first of all thank you for "The Dormouse Hollow" and "Dormouse Talk". They both are very useful.

Because of financial problems I am not able to go to control my nestboxes at two Glis sites and one Dryomys site. I am going to check them only in the end of September. So, at the moment I can not present data on Glis populations abundance in Lithuania this year.

I am checking nestboxes regularly only at my Muscardinus site. The results of the last nestboxes control on 4-7 September: in 272 nestboxes put up in grid I found 54 dormice (plus 3 litters with females). Population abundance is almost in the same level like last year. Population density is less then 1 adult in 1 hectare. The most interesting finding of the last control - a female with its third litter this year. Juveniles of the first two litters grew up successfully. This is the first such case during 19 year when I study Muscardinus.

It seems there is a competition between Glis and Muscardinus for nestboxes. In Lithuania, animals of both species can live in the same habitat, but usually only Glis occupy nestboxes. In the year, when abundance of Glis was very low, I found also Muscardinus in nestboxes, which usually were occupied by Glis. I think that finding of Muscardinus by Boris Kryštufek, when abundance of Glis is low, is analogous.

Last year I put 50 new nestboxes side by side to old nestboxes at one Glis site, and it was the first year (from 1990), when I found a lot of Muscardinus and Glis in nestboxes in autumn. In some places Glis were found in one nestbox and Muscardinus - in the adjacent. There is similar competition for nestboxes between Muscardinus and Apodemus flavicollis (see Juškaitis, 1995).

More information about competition between Muscardinus and other inhabitants of nestboxes (birds, mammals, social insects) in my paper Juškaitis R. 1995. Relations between common dormice (Muscardinus avellanarius) and other occupants of bird nest-boxes in Lithuania. Folia zoologica. 44 (4): 28-35.

Nestboxes have some positive influence to summer survival of Muscardinus (especially for juveniles), when weather conditions are bad (first of all long lasting rains). For example, after control of nestbox female carried its babies to natural nest. However after rainy week this natural nest was soggy and fallen down, and juveniles were in nestbox once again. When the weather is rainy for long time, number of Muscardinus using nestboxes increases. So, influence of nestboxes for dormice is positive and perhaps can determine negligible increase of autumnal abundance. However the main limiting factor for Muscardinus is winter mortality (Juškaitis, 1999), which does not depend on presence or absence of nestboxes. Regardless of presence of nestboxes density dependent self-regulation exists in Muscardinus populations: when population density is high in spring, reproduction intensity decreases and vice versa. I think you Werner are right affirming that "a certain habitat provides a certain amount of space for certain animals to live and survive in it", and additionally provided nestboxes do not provoke and cause an "overuse" of the area.

I also have a question about equipment for Muscardinus radiotracking. First of all I am interested in its price and where it is possible to purchase it.

With best wishes to all dormouser,
Rimvydas Juškaitis
Institute of Ecology, Akademijos 2, LT-2600 Vilnius, Lithuania

3) Reply (DT 1/4&5): Mating strategy and communal nesting (A. Pilastro)

Dear Werner,

Re: some of the questions on fat dormouse (Glis glis) reported in the DORMOUSE TALK no. 4 and 5:

One year old breeding females

In the two populations I have studied (one on the Colli Berici hills - Vicenza, Northern Italy, 200 asl, chestnut and oak wood - three years; the other in the Cansiglio Forest, southern side of the Alps, Treviso, Northern Italy, 1000 asl, beech forest - 9 years) I have regularly observed one year old breeding females. In some cases they were breeding with their mother, in other cases alone (in one cases two one-year sisters bred communally). The crucial point for breeding seems to be the body size (always >100g) rather than the age of the female (Pilastro 1992; Pilastro et al. 1994, 1996; Marin & Pilastro 1994).

Relatedness of co-nesting dormice and communal nesting

In both populations I observed two (in a couple of cases three) females breeding in the same nest boxes. In all cases in which their relatedness was known, they were closely related (mother-daughter, or sisters). It is difficult to say how and to what extent the two (or more) communally breeding females share their duties when caring for young. However, it seems evident that pups suck indiscriminately from the two females. However could not find any strong advantage in term of young quality (e.g. body mass ate weaning) in communal nests. The only effect we found was that one year females in communal nests bred one week earlier than solitarily breeding females of the same age. However, mortality at nest was slightly higher (although not significantly so) in communal nests compared to solitary nests (competition among litters? Cannibalism bythe older female?) (Pilastro 1992; Marin & Pilastro 1994; Pilastro et al. 1996).

I have also studied how the genetic similarity of individuals varies according to their distance (range 0-2000 m) in the Cansiglio pop (unpublished obs.). We sampled individuals in nest boxes spaced apart about 50 m and we compared their genetic similarity by means of multilocus DNA fingerprinting. Within 50-100 m we found that individuals are more similar than expected by chance, and females more than males. Their genetic similarity then slightly decreases and does not vary then very much. We sampled a small number of individuals of another pop about 40km away and isolated from the study population by two large valleys. They did not differ very much from the Cansiglio pop. The genetic structure fits well in the picture we have from direct observation of natal dispersal, which is suggesting that a consistent fraction of the young remains in the natal area (i.e. nest box), and that females are more phylopatric than males (as expected).

We have also very few (unpublished) data on paternity. We never found evidence of mixed paternity. This is apparently the case also for communal nests, where the pups from two litters are very likely sired by the same male (but we have data only for two communal nests).

Groups of domice in the same nest box

I found often more than one adult fat dormouse in the same nest box. During the 8 years (1991-1998) we regularly checked 100 nest boxes, we collected about 2400 records of occupied nest boxes. In about 450 of these cases we observed 3 or more inds. Larger assemblages are rarer, and we have about 60 cases with 6 or more inds (max no. of inds observed = 14). We used the typical nost-boxes for great tit.

The references can be found also in the appropriate section of the Dormouse Hollow. I hope this can be of some help.

I take the chance to thank you for the marvellous work you are doing with the Dormouse page and the chat.

All the best,

Andrea Pilastro
Department of Biology
University of Padova
Via U.Bassi 58/B
I-35131 Padova, ITALY
Home page:

4) Literature on Communal Nesting and Breeding (S. Bertolino)

Reply to WH: Mating strategy and more questions

Dear Werner
I think that in these articles from Pilastro you could find some answer to your questions, at least about communal investment in raising young.

Missiaglia E., 1996. Age-related reproductive success in solitary and communally nesting female dormice (Glis glis). J. Zool., Lond., 239: 601-608.

Pilastro A., 1992. Communal nesting between breeding females in a free-living population of fat dormice (Glis glis). Boll. Zool., 59: 63-68.

Marin G., Pilastro A., Communally breeding dormice, Glis glis, are close kin. Animal Behaviour. 47(6). 1994. 1485-1487.

Best wishes

DI.VA.P.R.A. Entomology & Zoology
Via L. da Vinci, 44
10095 Grugliasco (TO), Italy

5) Reply (DT 1/5): Three females and 19 young... (R. Baxter)

In Dormouse Talk 5, Tomi makes references to three Glis females and with 19 young in a single nest box in Slovenia. It would be valuable to know whether the females are sisters. If they are, then the possibility of communal raising of young is more easily explained.

I would appreciate it if somebody at Dormouse Hollow would post details of the nest-boxes that are being used (sizes, position of entrance etc), where they are positioned in trees, etc.

Many thanks

Rod Baxter
Department of Zoology
University of Fort Hare
P/Bag X1314
South Africa

6) Reply (DT 1/5): Competition for Nestboxes (R. Juškaitis)

Dear Sven,
I do not think that your example "first control: nest with eggs of Parus major, second: nest of Muscardinus and eaten eggs, third control: Ficedula hypoleuca and only in September again Muscardinus" means, that Ficedula raid Muscardinus. Muscardinus could left this nestbox because of your control or for other reasons.

At my study site another situation is typical. Usually in spring I do not remove old Muscardinus nests from nestboxes. In April and early May Muscardinus use these old nests. In middle May Ficedula can build their nest above these Muscardinus nest. Later Muscardinus can again occupy the same nestboxes with Ficedula nests and eggs. My experience with Apodemus flavicollis in nestboxes is the same as yours: they rather often raid Muscardinus. Sometimes I also used to find dead juveniles of Muscardinus with wounds, and I suppose, that A. flavicollis could do that. In spring bumble bees very often occupy old nests of Muscardinus in nestboxes, but seldom new nests of Muscardinus, which are continually used by dormice.

With best wishes,

P.S. How often did you find eggs of Parus major eaten by Muscardinus? Could you send me a copy of the paper: Mansfeld, K. (1942): Über das Auftreten von Bilchen in Vogelnistkästen und ihre Schäden an Vogelbruten. Dtsch. Vogelwelt 67,S.13-20.

7) Reply (DT 1/5): Overlap in Use of Nestboxes / Natural Nests (R. Juškaitis)

Dear Maurizio,
In Lithuania, situation with use of nestboxes by different animals is completely different than in your country. Overlap in the nestbox use is very wide.

Muscardinus and Dryomys appear in nestboxes in April, Glis - in May. At the same time hollow birds (first of all Ficedula hypoleuca, Parus major, Parus caeruleus) breed also in nestboxes. Glis and Dryomys have no problems with birds breeding in nestboxes: they can kill adult birds, eat their eggs or nestlings, occupy birds nests in nestboxes. In Lithuania, Muscardinus never kill adult birds or nestlings, but very often occupy nests of F.hypoleuca and eat their eggs (but sometimes eggs can be not eaten). On average about 10 % of F.hypoleuca nests used to be occupied by Muscardinus at my study sites. In the meantime I observed only 1 case (from many hundreds) when Muscardinus occupied nest of Parus major with eggs. So, there is a very large difference between Ficedula and Parus in this respect. I suppose that Parus, starting to breed earlier, can defend their nests. In autumn Muscardinus and Apodemus flavicollis settle nestboxes, and bigger and more aggressive Apodemus occupy nests of Muscardinus in nestboxes.

Also the same animals can use nestboxes of different size and with different entrance hole. For example, Muscardinus, Parus, Ficedula very often occupy bigger nestboxes suitable for Glis. Several times Muscardinus was found in large nestboxes for owls. Of course, bigger animals can not use small nestboxes with small entrance hole.

Your idea for Muscardinus "to check and count the natural nests and their owners in an area similar to that where are the nest boxes" is unrealizable in some cases. There are places where Muscardinus live, but it is impossible to find their natural nests (e.g. in mature forest stands with old hazels). Maybe Muscardinus natural nests are under ground in such places ? G.N.Likhachev also wrote about this problem. He could not find natural Muscardinus nests in his study site in Moscow region.

With best regards from Lithuania (from Muscardinus study site, which we visited last summer),


8) Glis Data from Switzerland (P. Vogel)

Glis data from Switzerland

I control 4 forests with 20 nestboxes each (copy of the English model). Glis occur only in two of these forests. The results agree with other continental observations:

Altitude 720 m, beech forest.
1999: 12 nestboxes with Glis, 4 of them with reproduction.
2000: 6 nestboxes with Glis, no reproduction.

Altitude 1200 m, mixed forest.
1999: 5 nestboxes with Glis, 4 of them with reproduction.
2000: no nestboxes with Glis, no reproduction.

Peter Vogel, 11.9.2000

Prof. Dr. Peter VOGEL
Institut d'Ecologie - Zoologie et Ecologie Animale
Bâtiment de Biologie
Université de Lausanne
CH 1015 Lausanne

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