scholarly journals The mating sites of the reindeer nose bot fly: not a practical target for control

Rangifer ◽  
1995 ◽  
Vol 15 (2) ◽  
pp. 55 ◽  
Author(s):  
Arne C. Nilssen ◽  
John R. Anderson
Keyword(s):  
Rangifer Tarandus ◽  
Target Species ◽  
Northern Norway ◽  
Bot Fly ◽  
Grazing Area ◽  
Cephenemyia Trompe ◽  
Number Of Males ◽  
Summer Grazing

The reindeer nose bot fly Cephenemyia trompe aggregates on hilltops/mountaintops to mate. Although active only for brief periods on certain days, males have been collected only from such sites. To evaluate possible suppression of the fly population by killing males (by insecticides or traps) at such sites, the density of sites and the number of males at each site were monitored in a summer grazing area of the semidomestic reindeer host (Rangifer tarandus) in Finnmark, northern Norway. In an area of ca. 20 km2, 19 mating sites were detected and examined during 4 hours on one day. The number of males observed at most sites was 5-16 (range 3-60). Minor hilltops had few males but at some sites >20-60 flies were dispersed over an area of at least 100 m2. It is concluded that mating sites in the study area are too numerous, and also used by many beneficial non-target species, to be practical targets for control of the species.

scholarly journals The timing and departure rate of larvae of the warble fly Hypoderma (= Oedemagena) tarandi (L.) and the nose bot fly Cephenemyia trompe (Modeer) (Diptera: Oestridae) from reindeer

Rangifer ◽  
1994 ◽  
Vol 14 (3) ◽  
pp. 113 ◽  
Author(s):  
Arne C. Nilssen ◽  
Rolf E. Haugerud
Keyword(s):  
Biological Control ◽  
Temporal Pattern ◽  
Rangifer Tarandus ◽  
Spring Migration ◽  
Slight Effect ◽  
Rangifer Tarandus Tarandus ◽  
Departure Time ◽  
Bot Fly ◽  
Cephenemyia Trompe

The emergence of larvae of the reindeer warble fly Hypoderma (= Oedemagena) tarandi (L.) (n = 2205) from 4, 9, 3, 6 and 5 Norwegian semi-domestic reindeer yearlings (Rangifer tarandus tarandus (L.)) was registered in 1988, 1989, 1990, 1991 and 1992, respectively. Larvae of the reindeer nose bot fly Cephenemyia trompe (Moder) (n = 261) were recorded during the years 1990, 1991 and 1992 from the same reindeer. A collection cape technique (only H. tarandi) and a grating technique (both species) were used. In both species, dropping started around 20 Apr and ended 20 June. Peak emergence occurred from 10 May - 10 June, and was usually bimodal. The temperature during the larvae departure period had a slight effect (significant only in 1991) on the dropping rate of H. tarandi larvae, and temperature during infection in the preceding summer is therefore supposed to explain the uneven dropping rate. This appeared to be due to the occurrence of successive periods of infection caused by separate periods of weather that were favourable for mass attacks by the flies. As a result, the temporal pattern of maturation of larvae was divided into distinct pulses. Departure time of the larvae in relation to spring migration of the reindeer influences infection levels. Applied possibilities for biological control by separating the reindeer from the dropping sites are discussed.

Epizootiology of the reindeer nose bot fly, Cephenemyia trompe (Modeer) (Diptera: Oestridae), in reindeer, Rangifer tarandus (L.), in Norway

1995 ◽  
Vol 73 (6) ◽  
pp. 1024-1036 ◽  
Author(s):  
Arne C. Nilssen ◽  
Rolf E. Haugerud
Keyword(s):  
Rangifer Tarandus ◽  
Negative Binomial ◽  
First Instar ◽  
High Infection ◽  
Bot Fly ◽  
Two Measures ◽  
Southern Norway ◽  
Major Factors ◽  
Cephenemyia Trompe ◽  
Host Behaviour

First-instar larvae of the reindeer nose bot fly, Cephenemyia trompe (Modeer) (Diptera: Oestridae), were sampled with a rinsing and sieving technique from 571 semidomesticated reindeer, Rangifer tarandus (L.), from different districts in northern Norway in the infection years 1983, 1984, 1985, 1987, and 1988, and from 44 wild reindeer from southern Norway (infection year 1983). This is the first comprehensive epizootiological study of this parasite from Fennoscandia. The first instar was found between 10 September to 25 May, the second instar from 11 February to 17 May, and the third instar from 3 April to 28 June. Old third-instar larvae were sometimes found trapped in the sinuses of the host. The overall prevalence of infection was 65.2% (range 6.7 – 100%) and the abundance (= relative density) was 11.53 (range 6.7 – 62.7). Individual intensities ranged from 0 to 221. There were significant differences in abundance between some districts and years. Distance and timing of the spring migration of the host are thought to be the major factors causing variability in infection levels between districts, whereas the summer climate during infection greatly influenced the differences between years. The frequency distribution was highly overdispersed (aggregated) and could adequately be described by the negative binomial model (overall parameter, k = 0.29, range 0.03 – 2.64). Heterogeneity in host behaviour during infestation is hypothesized to create this parasite distribution. Two measures of aggregation, Morisita's index of aggregation (IM) and1/k, decreased with larval burden, indicating that factors restricting parasite numbers (negative feedback) start to operate at high infection levels.

Parasite avoidance: the cause of post-calving migrations in Rangifer?

1991 ◽  
Vol 69 (9) ◽  
pp. 2423-2429 ◽  
Author(s):  
Ivar Folstad ◽  
Arne C. Nilssen ◽  
Odd Halvorsen ◽  
Johan Andersen
Keyword(s):  
Rangifer Tarandus ◽  
Total Sample ◽  
Parasitic Infections ◽  
Larval Abundance ◽  
Infective Stage ◽  
Migration Distance ◽  
Behavioural Adaptation ◽  
Summer Grazing ◽  
Parasite Avoidance ◽  
Hypoderma Tarandi

Intensities of warble fly larvae, Hypoderma tarandi (L.), were examined in slaughtered reindeer (Rangifer tarandus tarandus L.) from different summer grazing areas of Finnmark County, northern Norway. To test the hypothesis that larval abundance decreases with increase in post-calving migration distance (i.e., distance from calving grounds), herds with differing migration distances were sampled. The prevalence of infection in the total sample of 1168 animals was 99.9%. The study revealed significant differences in larval abundance among herds from different summer grazing areas. Herds with post-calving migrations have significantly lower larval abundances than herds remaining on or near the calving grounds for the whole summer. Between-herds variation in abundance of H. tarandi larvae is assumed to reflect differing densities of the infective stage (adult flies) on the herds' summer ranges. Larval abundance in a herd is in turn negatively correlated with the distance between the main larval shedding areas (i.e., calving grounds) and the areas of greatest transmission (i.e., summer pastures). These results are discussed in relation to transmission of other parasites common to Rangifer and suggest that this host's post-calving migration may be a behavioural adaptation that reduces levels of parasitic infections.

scholarly journals Utilization of old meadow by reindeer in spring in northern Norway

Rangifer ◽  
1999 ◽  
Vol 19 (1) ◽  
pp. 3 ◽  
Author(s):  
Svein M. Eilertsen ◽  
Ivar Schjelderup ◽  
Svein D. Mathiesen
Keyword(s):  
Food Intake ◽  
Rangifer Tarandus ◽  
Resting Metabolic Rate ◽  
Plant Production ◽  
Northern Norway ◽  
Daily Food ◽  
Grazing Period ◽  
The Difference ◽  
Initial Difference

<p>Utilization of abandoned coastal meadows in northern Norway by reindeer (Rangifer tarandus tarandus) were investigated for 25 days in spring 1996 (&laquo; = 12, 40-57 kg body mass (BM)) and 24 days in 1997 (&raquo; = 12, 39-61 kg BM). Grass production on grazed and ungrazed meadow was measured both years. Faecal dry matter (DM) production and ruminai in vitro DM digestibility (IVDMD) of selected plants were measured in the reindeer 15-22 days after the grazing experiment started each year. During the grazing period mean, standard deviation (s), temperature was 8.7, s = 2.8, &deg;C in 1996 and 11.0, s = 3.0, &deg;C in 1997, while temperature the first week was significantly higher in 1997 (P &lt; 0.05). Mean herbage mass, on ungrazed meadow (control), after one week of plant growth in 1996 (408, J" = 166, kg DM ha"1) was significantly different (P &lt; 0.05) from 1997 (576, s = 110, kg DM ha'). We believe the low temperature the first week in 1996 affected the plant production, and was the main reason for the significant (P &lt; 0.05) difference in mean daily plant DM production on the grazed meadow between 1996 (57, s = 16, kg DM ha') and 1997 (81, s = 16, kg DM ha"1). Mean ruminai IVDMD of a mixture of meadow plants, differed (P&lt;0.05) between 1996 (72.4, s = 1.0, %) and 1997 (83.9, s = 1.3, %), and mean daily food intake in 1996 (82, s = 13.5, g DM/kg0 75) was significantly lower than the intake in 1997 (131, s = 15.8, g DM/kg0 75). Daily digestible energy intake in reindeer was estimated to 0.96 Ml/kg07"5 X d 1 in 1996 and 1.85 Ml/kg""5 X d"1 in 1997, which was 1.3 and 2.5 times the resting metabolic rate in reindeer, respectively. We therefore assume the difference in food intake could be due to the initial difference in herbage mass.</p>

GAMMAHERPESVIRUS INFECTION IN SEMIDOMESTICATED REINDEER (RANGIFER TARANDUS TARANDUS): A CROSS-SECTIONAL, SEROLOGIC STUDY IN NORTHERN NORWAY

2013 ◽  
Vol 49 (2) ◽  
pp. 261-269 ◽  
Author(s):  
Carlos G. das Neves ◽  
Hanne M. Ihlebæk ◽  
Eystein Skjerve ◽  
Willy Hemmingsen ◽  
Hong Li ◽  
...  
Keyword(s):  
Rangifer Tarandus ◽  
Cross Sectional ◽  
Northern Norway ◽  
Rangifer Tarandus Tarandus
Sign in / Sign up

Export Citation Format

Share Document