High Performance Standards of Sirtrack VHF transmitters in the Research of an Endangered Deer in Patagonia
Client enquiry:
In 2000, Cristian Saucedo, DVM at the Center for Andean Wildlife Research in Chile contacted us about their project entitled: Huemul ecology research for conservation planning in southern Chile. The main goal of this project was to obtain information on huemul ecology and its relation to the main land use activities in the region, logging and domestic livestock grazing.
The huemul (Hippocamelus bisulcus) or southern Andean deer is a flagship species of the mountains and forest of southern Chile and Argentina, mainly in the Patagonian region. It is listed as critically endangered by the IUCN and its populations have declined drastically with an actual number of about 1000 animals.
Sirtrack response:
Sirtrack supplied 14 large mammal transmitters on synthetic collars together with three GPS collars. The VHF transmitters were programmed with a mortality signal which doubled the pulse rate when the transmitters were stationary for more than 24 hours indicating death.
To initiate the project, seventeen deer were captured and marked with radio-collars for subsequent monitoring.
Outcome:
Cristian Saucedo reports:
We have obtained valuable information on survival rates, causes of mortality, seasonal movements, and habitat use of this shy and rare species, all thanks to the Sirtrack wildlife transmitters (13 VHF radio-collars & 2 GPS units) used in the study. These transmitters have demonstrated excellent performance in extreme cold conditions in the mountain environment of Patagonia. Currently all transmitters are still working (> 4 years) and none have presented failures or difficulties during their operation.
In January 2002 we partially lost the signal of an adult collared male captured one year before and named “Chacabuco” N° 04. Weeks before (December 2001), the animal was observed being chased by another male across the large and cold Lake Cochrane, which is part of our study site. We thought perhaps the loss of the radio signal could be explained by the rugged terrain, which can complicate reception. After several days of searching with the antennas and radio receivers, the male was finally discovered. The deer was drowned in the lake at approximately 20-25 m of depth. A scuba diver pulled the animal from the lake for carcass examination and recovery of the collar, which to our surprise was still working!
We are very pleased with the performance of the Sirtrack radio-collars. Their high quality allowed us to know what happened with this male and with other individuals in the study area. We want to continue using Sirtrack in the next stage of our research with huemul in Patagonia.