Freie Universiẗat, Diss., 2004--Berlin. / Dateiformat: zip, Dateien im PDF-Format. Erscheinungsjahr an der Haupttitelstelle: 2004.

Die Ziele der vorliegenden Studien waren die Gewinnung umfassender ethologischer und endokrinologischer Daten zur Reproduktion des Marderhundes. In den ethologischen Unter-suchungen sollten das Ethogramm, das Aktogramm und spezielle fortpflanzungstypische Verhaltensweisen bei in Gehegen gehaltenen Tieren dokumentiert und mittels einjähriger Be-stimmung von Sexualsteroiden im Kot von männlichen und weiblichen Marderhunden die saisonale Rhythmik in den Hormonkonzentrationen dieser Wildkanidenart analysiert werden. Es wurden insgesamt 22 (9,13) Marderhunde in die Untersuchungen einbezogen, davon stan-den 12 (5,7) Tiere für die ethologischen und 16 (7,9) Tiere für die endokrinologischen Analy-sen zur Verfügung. Die ethologischen Studien fanden in 4 Tier- und Wildparks statt, in denen entweder ein Paar oder drei (1,2) Marderhunde gehalten wurden. Zwischen September 2005 und Juli 2006 wurden in den einzelnen Parks mehrere Beobachtungsintervalle von drei bis fünf Tagen durchgeführt. Die ebenfalls von September 2005 bis Juli 2006 frisch gesammelten Kotproben wurden bis zur Analyse bei -18 bis -20°C gelagert. Von jeder Probe erfolgte mittels eines EIA- Verfah-rens die Bestimmung der Testosteron-, Östron- und Progesteronkonzentration. Zusätzlich wurde untersucht, ob sich das Geschlecht der Tiere anhand von Hormonanalysen aus dem Kot bestimmen lässt. Marderhunde zeigen im Gehege verschiedene Arten der Lokomotion, nämlich Gehen, Trab, Galopp und Springen. Vertikales Klettern zeigen adulte Marderhunde nicht, die Neigung zum Graben ist gering. Als Ruhepositionen gibt es Liegen, Sitzen und Stehen. Das Anlegen von so genannten „Latrinen“, festen Kotplätzen, stellt eine Besonderheit beim Marderhund dar. So-wohl solitäre als auch soziale Spiele kommen nur selten vor; es lassen sich „Beute“- und „Laufspiele“ unterscheiden. Soziales Spielen wird oft durch ein Anspringen eingeleitet. Als Lautäußerungen lassen sich ein „Kontaktruf“ und ein „Abwehrlaut“ unterscheiden; unspezifi-sche Laute wie Fiepen, Knurren und Fauchen kommen ebenfalls vor. Es treten solitäre und soziale Formen der Körperpflege auf; soziale Körperpflege wird vermehrt in der Ranzzeit praktiziert. Aggressive Verhaltensweisen sind insgesamt sehr selten; in der Ranz kann es bei Tiergruppen mit mehreren Fähen und nur einem Rüden zur Aggression zwischen den Fähen kommen. Marderhunde sind im Sommer pro 24 Stunden aktiver als im Winter, in dem die Aktivität auf weniger als eine Stunde pro Tag sinken kann. Sind sie im Sommer halb tag-, halb nachtaktiv, so sind sie im Winter fast ausschließlich dämmerungs- und nachtaktiv. Auch bei den im Ge-hege gehaltenen Marderhunden tritt, als einzigartige Verhaltensweise unter den Caniden, wit-terungsabhängig eine Winterruhe auf. Bei den beobachteten Tieren konnten keine Kopulationen registriert werden und es wurden keine Würfe gefunden. Da es sich, mit einer Ausnahme, bei den Paaren um Vollgeschwister gehandelt hat, könnte dies Anzeichen einer Inzuchthemmung sein, die verhindert, dass sich Wurfgeschwister über Jahre hinweg paaren. Durch die endokrinologischen Analysen konnte die streng saisonale Reproduktion beim Mar-derhund dokumentiert werden. Bei den Rüden sind die Testosteronwerte von April bis Sep-tember konstant niedrig mit mittleren Konzentrationen von 100 bis 200 ng/g Kot. Ab Oktober steigen die Werte an, um im Februar ihr Maximum von 980 ng/g Kot zu erreichen. Bei den Fähen kommt es nur einmal im Jahr zu einem signifikanten Anstieg der Progesteronkon-zentration über das Basisniveau von 24 bis 57 ng/g Kot, welches von August bis Februar ein-gehalten wird. Im April werden die mittleren Jahreshöchstwerte von 260 ng Progesteron/g Kot erreicht. Die mittleren Östronwerte der Fähen variierten im Jahresverlauf nur wenig von-einander, die Konzentrationen bewegen sich zwischen 37 und 114 ng/g Kot. Mit Hilfe des Testosteron-Östron-Quotienten, des Testosteron-Progesteron-Quotienten und der absoluten Testosteronkonzentration sind die Geschlechter mittels Hormonanalyse aus Kotproben mit großer Sicherheit voneinander zu unterscheiden. Der verlässlichste Parameter ist dabei der Quotient aus Testosteron und Östron.

Die Ziele der vorliegenden Studien waren die Gewinnung umfassender ethologischer und endokrinologischer Daten zur Reproduktion des Marderhundes. In den ethologischen Unter-suchungen sollten das Ethogramm, das Aktogramm und spezielle fortpflanzungstypische Verhaltensweisen bei in Gehegen gehaltenen Tieren dokumentiert und mittels einjähriger Be-stimmung von Sexualsteroiden im Kot von männlichen und weiblichen Marderhunden die saisonale Rhythmik in den Hormonkonzentrationen dieser Wildkanidenart analysiert werden. Es wurden insgesamt 22 (9,13) Marderhunde in die Untersuchungen einbezogen, davon stan-den 12 (5,7) Tiere für die ethologischen und 16 (7,9) Tiere für die endokrinologischen Analy-sen zur Verfügung. Die ethologischen Studien fanden in 4 Tier- und Wildparks statt, in denen entweder ein Paar oder drei (1,2) Marderhunde gehalten wurden. Zwischen September 2005 und Juli 2006 wurden in den einzelnen Parks mehrere Beobachtungsintervalle von drei bis fünf Tagen durchgeführt. Die ebenfalls von September 2005 bis Juli 2006 frisch gesammelten Kotproben wurden bis zur Analyse bei -18 bis -20°C gelagert. Von jeder Probe erfolgte mittels eines EIA- Verfah-rens die Bestimmung der Testosteron-, Östron- und Progesteronkonzentration. Zusätzlich wurde untersucht, ob sich das Geschlecht der Tiere anhand von Hormonanalysen aus dem Kot bestimmen lässt. Marderhunde zeigen im Gehege verschiedene Arten der Lokomotion, nämlich Gehen, Trab, Galopp und Springen. Vertikales Klettern zeigen adulte Marderhunde nicht, die Neigung zum Graben ist gering. Als Ruhepositionen gibt es Liegen, Sitzen und Stehen. Das Anlegen von so genannten „Latrinen“, festen Kotplätzen, stellt eine Besonderheit beim Marderhund dar. So-wohl solitäre als auch soziale Spiele kommen nur selten vor; es lassen sich „Beute“- und „Laufspiele“ unterscheiden. Soziales Spielen wird oft durch ein Anspringen eingeleitet. Als Lautäußerungen lassen sich ein „Kontaktruf“ und ein „Abwehrlaut“ unterscheiden; unspezifi-sche Laute wie Fiepen, Knurren und Fauchen kommen ebenfalls vor. Es treten solitäre und soziale Formen der Körperpflege auf; soziale Körperpflege wird vermehrt in der Ranzzeit praktiziert. Aggressive Verhaltensweisen sind insgesamt sehr selten; in der Ranz kann es bei Tiergruppen mit mehreren Fähen und nur einem Rüden zur Aggression zwischen den Fähen kommen. Marderhunde sind im Sommer pro 24 Stunden aktiver als im Winter, in dem die Aktivität auf weniger als eine Stunde pro Tag sinken kann. Sind sie im Sommer halb tag-, halb nachtaktiv, so sind sie im Winter fast ausschließlich dämmerungs- und nachtaktiv. Auch bei den im Ge-hege gehaltenen Marderhunden tritt, als einzigartige Verhaltensweise unter den Caniden, wit-terungsabhängig eine Winterruhe auf. Bei den beobachteten Tieren konnten keine Kopulationen registriert werden und es wurden keine Würfe gefunden. Da es sich, mit einer Ausnahme, bei den Paaren um Vollgeschwister gehandelt hat, könnte dies Anzeichen einer Inzuchthemmung sein, die verhindert, dass sich Wurfgeschwister über Jahre hinweg paaren. Durch die endokrinologischen Analysen konnte die streng saisonale Reproduktion beim Mar-derhund dokumentiert werden. Bei den Rüden sind die Testosteronwerte von April bis Sep-tember konstant niedrig mit mittleren Konzentrationen von 100 bis 200 ng/g Kot. Ab Oktober steigen die Werte an, um im Februar ihr Maximum von 980 ng/g Kot zu erreichen. Bei den Fähen kommt es nur einmal im Jahr zu einem signifikanten Anstieg der Progesteronkon-zentration über das Basisniveau von 24 bis 57 ng/g Kot, welches von August bis Februar ein-gehalten wird. Im April werden die mittleren Jahreshöchstwerte von 260 ng Progesteron/g Kot erreicht. Die mittleren Östronwerte der Fähen variierten im Jahresverlauf nur wenig von-einander, die Konzentrationen bewegen sich zwischen 37 und 114 ng/g Kot. Mit Hilfe des Testosteron-Östron-Quotienten, des Testosteron-Progesteron-Quotienten und der absoluten Testosteronkonzentration sind die Geschlechter mittels Hormonanalyse aus Kotproben mit großer Sicherheit voneinander zu unterscheiden. Der verlässlichste Parameter ist dabei der Quotient aus Testosteron und Östron.

Abstract Between October 1999 and October 2003, 30 adult and 48 young (< 1 year) raccoon dogs (Nyctereutes procyonoides) were monitored using radio-telemetry in an area of Germany which has been occupied by this invasive alien species since the early 1990s. Additionally, three pairs of raccoon dogs were observed by continuous radio-tracking during the first six weeks after parturition in 2003. Furthermore 136 raccoon dog pubs were ear-tagged between June 1999 and August 2006. No adult animals dispersed from the area during the study period and home ranges tended to be used for several years, probably for life. The average annual home range size, calculated using 95% fixed kernel, was 382.2 ha ± 297.4 SD for females (n = 30 seasonal home ranges) and 352.4 ha ± 313.3 SD for males (n = 32 seasonal home ranges). Paired raccoon dogs had home ranges of similar size, with pair sharing the same area all year round. Raccoon dogs occupied large core areas (85% kernel) covering 81.2% of their home ranges. The home ranges were at their smallest during the mating season. The slightly larger size of home ranges in winter suggests that, due to the temperate climate, raccoon dogs do not hibernate in Germany. Males and females formed a long-term (probably lifelong) pair bond. Same-sex neighbours ignored each other and even adjacent males/females showed neither preference nor avoidance. Thus, it can be assumed that the raccoon dog in Central Europe is monogamous without exclusive territories, based on the results of home range overlap analysis and interaction estimations. Habitat composition within home ranges and within the whole study area was almost equal. Although, percentage shares of farmland and meadow was 16.35% smaller and 12.06% higher within the home ranges, respectively. All nine habitat types (farmland, forest, settlement, water, meadows, maize fields, small woods, reeds and hedges) were used opportunistically by raccoon dogs. No significant, recognisable difference for habitat preferences between seasons was detected. Male and female raccoon dog showed equal habitat preference pattern. A comparison of active and inactive locations in different habitats found no remarkable differences. Habitat composition of individual home ranges was used to classify animals. If the percentage of forest within a home range exceeded 50% the individual was classified as a ‘forest type’ raccoon dog. If the percentage of forest habitats within a home range was less than 5%, the share of pastureland was mean 81.82% ± 16.92 SD. Consequently the individual was classified as a ‘agrarian type’ raccoon dog. Neither habitat preference nor habitat selection process differed between the two ‘types’. Habitat use and preference is discussed with relation to the ability of the raccoon dog to expand its range towards Western Europe. Males spent noticeably more time (40.5% of the time ±11.7 SD) alone with the pups than females (16.4% of the time ±8.5 SD). Females had noticeably larger 95% kernel home ranges (98.24 ha ±51.71 SD) than males (14.73 ha ±8.16 SD) and moved much longer daily distances (7,368 m ±2,015 SD) than males (4,094 m ±2,886 SD) in six weeks postpartum. The raccoon dogs being studied left the breeding den in the 6th week after the birth of the pups. In situ video observation showed that the male carried prey to the den to provide the female and the litter with food. A clear division of labour took place among parents during the period in which the pups were nursed: males guarded the litter in the den or in close vicinity of it, while the females foraged to satisfy their increased energy requirements. There were relocations of 59 (43.4%) ear-tagged young racoon dogs and mean distance from marking point was 13.5 km ±20.1 SD. Dispersal mortality rate was 69.5% among young raccoon dogs. Most animals (55.9%) were recovered nearer than 5 km from the marking point, whereas only 8.5% relocations were recorded further than 50 km from the marking point. There was no difference in the distances of relocations between sexes. Most (53.7%) relocations of ear-tagged young raccoon dogs were in August and September and, only 34.1% were recorded from October to April. Hunting (55 %) and traffic (27 %) were the major mortality factors. Radio-collared young raccoon dogs generally dispersed between July and September. The mean natal home range size (MCP 100%) with and without excursions was 502.6 ha ±66.4 SD (n = 9) and 92.1 ha ±66.4 SD (n = 17), respectively. There were no differences between sexes in the month of dispersal. The direction of travel for dispersing animals appeared to be random, with distances from 0.5 km to 91.2 km. A highly flexible dispersing behaviour is certainly one of the reasons which contribute to the high expansion success of the species.

Between October 1999 and October 2003, 30 adult and 48 young (< 1 year) raccoon dogs (Nyctereutes procyonoides) were monitored using radio-telemetry in an area of North-East Germany which has been occupied by this invasive alien species since the early 1990s. Additionally, three pairs of raccoon dogs were observed by continuous radio-tracking during the first six weeks after parturition in 2003. Furthermore 136 raccoon dog pubs were ear-tagged between June 1999 and August 2006. No adult animals dispersed from the area during the study period and home ranges tended to be used for several years, probably for life. The average annual home range size, calculated using 95% fixed kernel, was 382.2 ha ± 297.4 SD for females (n = 30 seasonal home ranges) and 352.4 ha ± 313.3 SD for males (n = 32 seasonal home ranges). Paired raccoon dogs had home ranges of similar size, with pair mates sharing the same area all year round. Raccoon dogs occupied large core areas (85% kernel) covering 81.2% of their home ranges. The home ranges were at their smallest during the mating season. The slightly larger size of home ranges in winter suggests that, due to the temperate climate, raccoon dogs do not hibernate in Germany. Males and females formed a long-term (probably lifelong) pair bond. Same-sex neighbours ignored each other and even adjacent males/females showed neither preference nor avoidance. Thus, it can be assumed that the raccoon dog in Central Europe is monogamous without exclusive territories, based on the results of home range overlap analysis and interaction estimations. Habitat composition within home ranges and within the whole study area was almost equal. Although, percentage shares of farmland and meadow was 16.35% smaller and 12.06% higher within the home ranges, respectively. All nine habitat types (farmland, forest, settlement, water, meadows, maize fields, small woods, reeds and hedges) were used opportunistically by raccoon dogs. No significant, recognisable difference for habitat preferences between seasons was detected. Male and female raccoon dog showed equal habitat preference pattern. A comparison of active and inactive locations in different habitats found no remarkable differences. Habitat composition of individual home ranges was used to classify animals. If the percentage of forest within a home range exceeded 50% the individual was classified as a ‘forest type’ raccoon dog. If the percentage of forest habitats within a home range was less than 5%, the share of pastureland was mean 81.82% ± 16.92 SD. Consequently the individual was classified as a ‘agrarian type’ raccoon dog. Neither habitat preference nor habitat selection process differed between the two ‘types’. Habitat use and preference is discussed with relation to the ability of the raccoon dog to expand its range towards Western Europe. Males spent noticeably more time (40.5% of the time ±11.7 SD) alone with the pups than females (16.4% of the time ±8.5 SD). Females had noticeably larger 95% kernel home ranges (98.24 ha ±51.71 SD) than males (14.73 ha ±8.16 SD) and moved much longer daily distances (7,368 m ±2,015 SD) than males (4,094 m ±2,886 SD) in six weeks postpartum. The raccoon dogs being studied left the breeding den in the 6th week after the birth of the pups. In situ video observation showed that the male carried prey to the den to provide the female and the litter with food. A clear division of labour took place among parents during the period in which the pups were nursed: males guarded the litter in the den or in close vicinity of it, while the females foraged to satisfy their increased energy requirements. There were relocations of 59 (43.4%) ear-tagged young raccoon dogs and mean distance from marking point was 13.5 km ±20.1 SD. Dispersal mortality rate was 69.5% among young raccoon dogs. Most animals (55.9%) were recovered nearer than 5 km from the marking point, whereas only 8.5% relocations were recorded further than 50 km from the marking point. There was no difference in the distances of relocations between sexes. Most (53.7%) relocations of ear-tagged young raccoon dogs were in August and September and, only 34.1% were recorded from October to April. Hunting (55 %) and traffic (27 %) were the major mortality factors. Radiocollared young raccoon dogs generally dispersed between July and September. The mean natal home range size (MCP 100%) with and without excursions was 502.6 ha ±66.4 SD (n = 9) and 92.1 ha ±66.4 SD (n = 17), respectively. There were no differences between sexes in the month of dispersal. The direction of travel for dispersing animals appeared to be random, with distances from 0.5 km to 91.2 km. A highly flexible dispersing behaviour is certainly one of the reasons which contribute to the high expansion success of the species.

Abstract Between October 1999 and October 2003, 30 adult and 48 young (&amp;lt; 1 year) raccoon dogs (Nyctereutes procyonoides) were monitored using radio-telemetry in an area of Germany which has been occupied by this invasive alien species since the early 1990s. Additionally, three pairs of raccoon dogs were observed by continuous radio-tracking during the first six weeks after parturition in 2003. Furthermore 136 raccoon dog pubs were ear-tagged between June 1999 and August 2006. No adult animals dispersed from the area during the study period and home ranges tended to be used for several years, probably for life. The average annual home range size, calculated using 95% fixed kernel, was 382.2 ha ± 297.4 SD for females (n = 30 seasonal home ranges) and 352.4 ha ± 313.3 SD for males (n = 32 seasonal home ranges). Paired raccoon dogs had home ranges of similar size, with pair sharing the same area all year round. Raccoon dogs occupied large core areas (85% kernel) covering 81.2% of their home ranges. The home ranges were at their smallest during the mating season. The slightly larger size of home ranges in winter suggests that, due to the temperate climate, raccoon dogs do not hibernate in Germany. Males and females formed a long-term (probably lifelong) pair bond. Same-sex neighbours ignored each other and even adjacent males/females showed neither preference nor avoidance. Thus, it can be assumed that the raccoon dog in Central Europe is monogamous without exclusive territories, based on the results of home range overlap analysis and interaction estimations. Habitat composition within home ranges and within the whole study area was almost equal. Although, percentage shares of farmland and meadow was 16.35% smaller and 12.06% higher within the home ranges, respectively. All nine habitat types (farmland, forest, settlement, water, meadows, maize fields, small woods, reeds and hedges) were used opportunistically by raccoon dogs. No significant, recognisable difference for habitat preferences between seasons was detected. Male and female raccoon dog showed equal habitat preference pattern. A comparison of active and inactive locations in different habitats found no remarkable differences. Habitat composition of individual home ranges was used to classify animals. If the percentage of forest within a home range exceeded 50% the individual was classified as a ‘forest type’ raccoon dog. If the percentage of forest habitats within a home range was less than 5%, the share of pastureland was mean 81.82% ± 16.92 SD. Consequently the individual was classified as a ‘agrarian type’ raccoon dog. Neither habitat preference nor habitat selection process differed between the two ‘types’. Habitat use and preference is discussed with relation to the ability of the raccoon dog to expand its range towards Western Europe. Males spent noticeably more time (40.5% of the time ±11.7 SD) alone with the pups than females (16.4% of the time ±8.5 SD). Females had noticeably larger 95% kernel home ranges (98.24 ha ±51.71 SD) than males (14.73 ha ±8.16 SD) and moved much longer daily distances (7,368 m ±2,015 SD) than males (4,094 m ±2,886 SD) in six weeks postpartum. The raccoon dogs being studied left the breeding den in the 6th week after the birth of the pups. In situ video observation showed that the male carried prey to the den to provide the female and the litter with food. A clear division of labour took place among parents during the period in which the pups were nursed: males guarded the litter in the den or in close vicinity of it, while the females foraged to satisfy their increased energy requirements. There were relocations of 59 (43.4%) ear-tagged young racoon dogs and mean distance from marking point was 13.5 km ±20.1 SD. Dispersal mortality rate was 69.5% among young raccoon dogs. Most animals (55.9%) were recovered nearer than 5 km from the marking point, whereas only 8.5% relocations were recorded further than 50 km from the marking point. There was no difference in the distances of relocations between sexes. Most (53.7%) relocations of ear-tagged young raccoon dogs were in August and September and, only 34.1% were recorded from October to April. Hunting (55 %) and traffic (27 %) were the major mortality factors. Radio-collared young raccoon dogs generally dispersed between July and September. The mean natal home range size (MCP 100%) with and without excursions was 502.6 ha ±66.4 SD (n = 9) and 92.1 ha ±66.4 SD (n = 17), respectively. There were no differences between sexes in the month of dispersal. The direction of travel for dispersing animals appeared to be random, with distances from 0.5 km to 91.2 km. A highly flexible dispersing behaviour is certainly one of the reasons which contribute to the high expansion success of the species.

Between October 1999 and October 2003, 30 adult and 48 young (< 1 year) raccoon dogs (Nyctereutes procyonoides) were monitored using radio-telemetry in an area of North-East Germany which has been occupied by this invasive alien species since the early 1990s. Additionally, three pairs of raccoon dogs were observed by continuous radio-tracking during the first six weeks after parturition in 2003. Furthermore 136 raccoon dog pubs were ear-tagged between June 1999 and August 2006. No adult animals dispersed from the area during the study period and home ranges tended to be used for several years, probably for life. The average annual home range size, calculated using 95% fixed kernel, was 382.2 ha ± 297.4 SD for females (n = 30 seasonal home ranges) and 352.4 ha ± 313.3 SD for males (n = 32 seasonal home ranges). Paired raccoon dogs had home ranges of similar size, with pair mates sharing the same area all year round. Raccoon dogs occupied large core areas (85% kernel) covering 81.2% of their home ranges. The home ranges were at their smallest during the mating season. The slightly larger size of home ranges in winter suggests that, due to the temperate climate, raccoon dogs do not hibernate in Germany. Males and females formed a long-term (probably lifelong) pair bond. Same-sex neighbours ignored each other and even adjacent males/females showed neither preference nor avoidance. Thus, it can be assumed that the raccoon dog in Central Europe is monogamous without exclusive territories, based on the results of home range overlap analysis and interaction estimations. Habitat composition within home ranges and within the whole study area was almost equal. Although, percentage shares of farmland and meadow was 16.35% smaller and 12.06% higher within the home ranges, respectively. All nine habitat types (farmland, forest, settlement, water, meadows, maize fields, small woods, reeds and hedges) were used opportunistically by raccoon dogs. No significant, recognisable difference for habitat preferences between seasons was detected. Male and female raccoon dog showed equal habitat preference pattern. A comparison of active and inactive locations in different habitats found no remarkable differences. Habitat composition of individual home ranges was used to classify animals. If the percentage of forest within a home range exceeded 50% the individual was classified as a ‘forest type’ raccoon dog. If the percentage of forest habitats within a home range was less than 5%, the share of pastureland was mean 81.82% ± 16.92 SD. Consequently the individual was classified as a ‘agrarian type’ raccoon dog. Neither habitat preference nor habitat selection process differed between the two ‘types’. Habitat use and preference is discussed with relation to the ability of the raccoon dog to expand its range towards Western Europe. Males spent noticeably more time (40.5% of the time ±11.7 SD) alone with the pups than females (16.4% of the time ±8.5 SD). Females had noticeably larger 95% kernel home ranges (98.24 ha ±51.71 SD) than males (14.73 ha ±8.16 SD) and moved much longer daily distances (7,368 m ±2,015 SD) than males (4,094 m ±2,886 SD) in six weeks postpartum. The raccoon dogs being studied left the breeding den in the 6th week after the birth of the pups. In situ video observation showed that the male carried prey to the den to provide the female and the litter with food. A clear division of labour took place among parents during the period in which the pups were nursed: males guarded the litter in the den or in close vicinity of it, while the females foraged to satisfy their increased energy requirements. There were relocations of 59 (43.4%) ear-tagged young raccoon dogs and mean distance from marking point was 13.5 km ±20.1 SD. Dispersal mortality rate was 69.5% among young raccoon dogs. Most animals (55.9%) were recovered nearer than 5 km from the marking point, whereas only 8.5% relocations were recorded further than 50 km from the marking point. There was no difference in the distances of relocations between sexes. Most (53.7%) relocations of ear-tagged young raccoon dogs were in August and September and, only 34.1% were recorded from October to April. Hunting (55 %) and traffic (27 %) were the major mortality factors. Radiocollared young raccoon dogs generally dispersed between July and September. The mean natal home range size (MCP 100%) with and without excursions was 502.6 ha ±66.4 SD (n = 9) and 92.1 ha ±66.4 SD (n = 17), respectively. There were no differences between sexes in the month of dispersal. The direction of travel for dispersing animals appeared to be random, with distances from 0.5 km to 91.2 km. A highly flexible dispersing behaviour is certainly one of the reasons which contribute to the high expansion success of the species.