Short-term behavioural responses of Svalbard reindeer to direct provo ...

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Tromsø, Norway. Summary: Short-term behavioural responses of. 101 groups of Svalbard reindeer (Rangifer taran- dus platyrhynchus) to direct provocation by a.
of considering that this is a concern o n l y of others. A n t h e l m i n t i c resistance w i l l not disappear spontaneously, and must inevitably increase if the traditional methods of w o r m c o n t r o l continue t o be practised. It is unrealistic to assume that the development and release of alternative, h i g h l y effective anthelmintics w i l l keep pace w i t h resistance to existing drugs. N o r can one be sanguine about the expectation that non-chemotherapeutic methods (such as w o r m vaccines) w i l l resolve this p r o b l e m i n the short term.

It is d o u b t f u l whether c o n t r o l programmes w h i c h have anthelmintic treatment as a c o m p o nent can avoid selecting for resistance. H o w ever, i f users of anthelmintics are made aware of the best ways t o use these drugs t o extend o r maintain their effectivenes, this w i l l a l l o w more time t o explore the possibilities of other methods of w o r m c o n t r o l .

Short-term behavioural responses of Svalbard reindeer to direct provocation by a snowmobile N. J. C. Tyler1 1

Department of Arctic Biology and Institute of Medical Biology, University of Tromsø, Breivika, N-9000 Tromsø, Norway.

Summary: Short-term behavioural responses o f 101 groups of Svalbard reindeer (Rangifer tarandus platyrhynchus) to direct p r o v o c a t i o n b y a s n o w m o b i l e were recorded i n A p r i l (late w i n ter) 1987. T h e median size of groups = 3.3 animals. Reindeers 7 first visible responses to an app r o a c h i n g s n o w m o b i l e usually i n v o l v e d independent behaviour b y different individuals i n a group. F l i g h t , b y contrast, was a co-ordinated group response. G r o u p s ' median response distances were: m i n i m u m reaction distance = 640 m, disturbance distance = 410 m , distance at initial flight = 80 m and distance of flight = 160 m . G r o u p s ' median response times were: total r u n n i n g time = 22 s, total l o c o m o t i o n time = 38 s, m a x i m u m duration of disturbance = 193 s. E n e r g y and time budget models indicate that one median flight response can cause an increase i n a reindeer's daily energy expenditure ( D E E ) of approximately 0.4 % and a loss of daily grazing time ( D G T ) also of 0.4 % . C o r r e sponding values for one m a x i m u m and one m i n i m u m flight response are 4.7 % and 0.01 % of D E E and 4.6 % and 0.03 % of D G T , respectivel y . T h e rate of disturbance of reindeer b y normal s n o w m o b i l e traffic, measured d u r i n g 24 h 18

watches of groups of animals, was one disturbance per group per t w o days. Reindeer w h i c h were disturbed b y n o r m a l traffic w a l k e d away s l o w l y but never ran at all d u r i n g this series of observations. T h i s study, w h i c h considered o n l y reindeers' immediate, overt responses to p r o v o c a t i o n and w h i c h purposely ignored all psychological and physiological aspects, failed to detect a n y w a y in w h i c h the current level of s n o w m o b i l e traffic might substantially reduce the physical wellbeing of Svalbard reindeer. T h i s surprising c o n c l u s i o n is based p r i n c i p a l l y o n consideration of the l o w frequency w i t h w h i c h the animals are o v e r t l y disturbed b y n o r m a l s n o w m o b i l e traffic together w i t h the short duration of their response to disturbance. C l e a r l y , also, there is no reason t o expect Svalbard reindeer t o respond t o p r o v o c a t i o n i n the same w a y as other subspecies o f Rangifer. C a r i b o u o r continental w i l d reindeer live under constant threat o f suddenly having to gallop off f r o m b i t i n g flies, wolves, hunters etc. H a v i n g t o escape f r o m things i n a h u r r y is part of their daily life; f o r Svalbard reindeer this is not the case.

Rangifer,

Special Issue No. 4,1990