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1

Home ranges of European mink Mustela lutreola in Southwestern Europe

100%
Garin I., Zuberogoitia I., Zabala J., Aihartza J., Clevenger A. P., Rallo A.
Acta Theriologica
|
2002
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tom 47
|
nr 1
We radiotracked 7 European mink Mustela lutreola Linnaeus, 1761 (5 males and 2 females), to determine their distribution, size and temporal changes of their home range in an area of southwestern Europe, where American mink M. vison was not established. Size of home ranges varied from 11 to 17 km along watercourses in males and were 0.6 and 3.6 km in females. Home ranges of males were larger than those found in previous studies. Most females captured (either radiotracked or not) were found within the home range of males. Males occupied adjoining river sections with minimal range overlap, suggesting an intrasexually exclusive spacing pattern for males. Each month males used new river stretches, mainly along tributaries; meanwhile they showed a steady use of their stem river section. Resting sites were mainly beneath dense brambles of Rubus patches located in the river bank.
2

Ranging and parental care of the raccoon dog Nyctereutes procyonoides during pup rearing

100%
Drygala F., Zoller H., Stier N., Mix H., Roth M.
Acta Theriologica
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2008
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tom 53
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nr 2
Three pairs of raccoon dogsNyctereutes procyonoides (Gray, 1834) were observed by continuous radio-tracking (one 24-h session, once a week) during the first six weeks after parturition. Males spent noticeably more time (40.5% ±11.7 SD) alone with the pups than females (16.4% ±8.5 SD). Females had noticeably larger home ranges (95% kernel: 98.24 ha ±51.71 SD) than males (14.73 ha ±8.16 SD) and moved much longer daily distances (7368 m ±2015 SD) than males (4094 m ±2886 SD) in six weeks postpartum. The raccoon dogs 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.
3

Speed and actual distances travelled by radiocollared wolves in Bialowieza Primeval Forest [Poland]

100%
Musiani M., Okarma H., Jedrzejewski W.
Acta Theriologica
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1998
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tom 43
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nr 4
The relationship between the straight line distances (SLD), obtained from tele­metry locations, and actual distances travelled by wolves Canis lupus (ADT), measured by snowtracking, was investigated in Białowieża Primeval Forest, E Poland, in winter 1995/96. Radiolocations determined at 15-min time intervals approximated the ADT by wolves reasonably well. If wolves were relocated at 0.5- to 2-h intervals, SLD can be multiplied by a correction factor of 1.3 to obtain ADT. Within the range of SLD from 1 to 10 km, they could also be converted into ADT using a regression equation: ADT = 0.34 + 1.19(SLD), with standard errors of prediction ± 0.13 to ± 0.3 km. The average travelling speed of wolves was 3.78 km/h (SD 1.23, range 1.6-6.1 km). Wolves walking the forest trails, roads and frozen rivers moved significantly faster than in the forest. Also, individuals travelling with other pack members moved faster than those walking singly.
4

Accuracy of radio-tracking to estimate activity and distances walked by European bison in the Bialowieza Forest, Poland

84%
Rouys S., Theuerkauf J., Krasinska M.
Acta Theriologica
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2001
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tom 46
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nr 3
To determine the accuracy of radio-tracking estimates of activity and distances walked by European bison Bison bonasus (Linnaeus, 1758), we observed bison while simultaneously conducting radio-tracking in the Białowieża Forest (Poland). Single radio-tracking estimates often did not represent the actual activity of the bison, but the mean time spent active calculated from radio-tracking and direct observations did not differ significantly. Radio-tracking provided overestimates of the distances walked by bison when the animals walked between 0 and 25 m and underestimated the distances walked by bison if they walked further than 25 m in a radio-tracking interval. Activity was best estimated when radio-trackers were between 200 and 300 m from the bison. The mean activity calculated with a sampling interval of 15 min needed about 8 days of radio-tracking and the mean of distances walked about 35 tracking days to stabilise. We concluded that collars without activity sensors can measure the mean activity of bison but cannot represent the length of their activity bouts or the type of their activity and that our radio-tracking estimates of distances walked by bison needed to be corrected before further analyses.
5

Individual variations of daily activity patterns in radiotracked European hares during winter

84%
Pepin D., Cargnelutti B.
Acta Theriologica
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1994
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tom 39
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nr 4
Daily movements during winter of 2 adult male (Nos 1 and 3) and 2 adult female (Nos 2 and 4) radiotracking hares Lepus europaeus Pallas, 1778 were estimated from simultaneous bearings using a 50 x 50 m grid. As deduced every 4 h both from the average rate of recorded changes of squares on the grid, and from the average distance travelled, we found that the hares had a typically nocturnal locomotor activity pattern. However, when comparing individual data, we found that significant variations oc­curred from 12.00 to 15.59, and between 00.00 and 07.59. We also estimated that the average daily activity of the hares started near sunset (mean = 23 min after sunset, range + 110 min), and ended near sunrise (mean = 14 min before sunrise, range ± 60 min), male No 1 usually spending more time in activity than the 3 other specimens, Finally, we assessed the differences in nocturnal distance travelled between indi­viduals (Nos 2, 3, and 4) for a given period (during week 6, mean = 3.91 km, range 6.02-2.62), and also during several nights (during weeks 6, 8, 10 and 12) for male No 3. We concluded that some inter- and intra-individual variations of activity patterns occurred on various time scales (day-to-day or during a given night), such differences probably contributing to confuse predators.
6

Optimal radio-tracking strategy - The best results with the least effort?

84%
Kauhala K., Holmala K.
Acta Theriologica
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2008
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tom 53
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nr 4
We tested the need to radio-track nocturnal mammals, such as raccoon dogsNyctereutes procyonoides (Gray, 1834) and badgersMeles meles (Linnaeus, 1758), throughout the night for reliable estimates of home range size and habitat selection. We also tested the possibility to reduce the tracking effort by decreasing the number of tracking-nights. The results indicated that the locations collected before midnight gave good estimates of home range sizes but those collected after midnight or by reducing the number of tracking-nights resulted in smaller home ranges than those estimated using the total data. Thus, if one aims to estimate only the home range size, locations before midnight would be adequate. Locations of raccoon dogs taken only before or after midnight did not reveal all habitats, which were favoured on the basis of the total data. Although locations of badgers before midnight seemed to give correct results of habitat selection, we recommend radio-tracking also badgers at least few times through the night, because their core areas shifted during the night. In the case of badgers, but not of raccoon dogs, we obtained correct results of habitat selection by reducing the tracking effort by decreasing the number of tracking-nights.
7

Characteristics of the European hare Lepus europaeus use of space in a French agricultural region of intensive farming

67%
Reitz F., Leonard Y.
Acta Theriologica
|
1994
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tom 39
|
nr 2
Fifty-one European hares Lepus europaeus Pallas, 1778 were monitored during at least one month by radiotracking in an intensively farmed landscape. The mean home range size of 21 hares monitored during at least six months was about 100 ha. During summer and autumn, seasonal home range size and the mean distance between fixes did not reveal any difference in the use of space between sexes or between age classes. However, according to the shifts of monthly resting range centres, females seemed to be more sedentary than males. The night-time activity range was often larger than the daytime resting range and partly or totally overlapped it although resting and activity locations were rarely the same, Hare movements did not show any important changes in response to crop harvesting or shooting.
8

Predation of Eurasian lynx on roe deer and red deer in Bialowieza Primeval Forest, Poland

67%
Okarma H., Jedrzejewski W., Schmidt K., Kowalczyk R., Jedrzejewska B.
Acta Theriologica
|
1997
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tom 42
|
nr 2
Patterns of lynx Lynx lynx {Linnaeus, 1758) predation on ungulates were studied in the Polish part of Białowieża Primeval Forest (580 km ) from scats and prey remains of iynx between 1985-1996, and radiotracking of IS lynx between 1991-1996, Cervids were the main prey and constituted 90% of food biomass consumed (analysis of faeces) and 84% of prey killed. Roe deer Capreotus capreolus was positively selected by all lynx (though stronger by females and subadults than by adult males). Fawns and adult roe deer of both sexes were preyed on in proportion to their abundance in the population. Red deer Ceruus elaphus was taken less often than would have been expected at random, and fawns were positively selected by lynx. On average, lynx spent 76 h (3.2 days) feeding on a killed deer (from 38 h in a female with 3 kittens to 105 h in single adult females). Mean searching time (ie time from leaving the remains of one deer to killing another one) was 52 h (2.2 days); from 10 h in a female with 3 young to 104 h in subadults. Thus, the average kill rate by lynx was one deer per 5.4 days. Predation impact of lynx population on roe and red deer was estimated in 1991-1996, when recorded numbers were 288-492 roe deer and 359-607 red deer per 100 km" in late winter (March), and 501-820 roe deer and 514-858 red deer per 100 km" in spring (May/June). During that period densities of deer declined markedly due to deliberately elevated hunting harvest by forestry personnel, aimed at reduction of game damage to silviculture. Densities of adult lynx were little variable (2.4-3.2 inds/100 km2), but reproduction rate strongly varied in response to deer decline, from 0.67 juv/adult lynx in 1991/92 to 0.25 juv/adult lynx in 1995/96. Annually, lynx population killed 110-169 roe deer/100 km2, which constituted 21-36% of spring (seasonally highest) numbers of roe deer. Lynx predation was the most important factor of roe deer mortality. Furthermore, lynx population took 42-70 red deer/100 km2 annually, which constituted 6-13% of spring number of red deer. In red deer mortality, lynx predation played an inferior role to hunting harvest and wolf predation.
9

Differential mobility in two small phyllostomid bats, Artibeus watsoni and Micronycteris microtis, in a fragmented neotropical landscape

67%
Albrecht L., Meyer C. F. J., Kalko E. K. V.
Acta Theriologica
|
2007
|
tom 52
|
nr 2
To assess the influence of habitat fragmentation on small bats, we determined home range size and mobility of the frugivorousArtibeus watsoni Thomas, 1901 and the gleaning insectivorousMicronycteris microtis Miller, 1898 by radiotracking on different-sized islands (2.7–17 ha) in Lake Gatún, Panamá. The two species differed in their response to fragmentation. Home range size was highly variable in the five trackedA. watsoni, ranging from 1.8 to 17.9 ha with a mean of about 9 ha. Some individuals flew regularly between islands and/or the mainland, thereby traversing up to 180 m of open water. In comparison, home ranges of threeM. microtis were with about 3.8 ha only half as large. All ofM. microtis exhibited sedentary foraging behaviour and did not cross open water, suggesting that they might persist at least on some of the islands as resident populations. Our findings are consistent with radiotracking data from a previous study and indicate that small habitat patches are still used by small bats, provided the degree of isolation is low and that sufficient resources and larger habitat patches exist in close vicinity, potentially acting as additional feeding grounds and source populations.
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