The Baird's Tapir Project of Costa Rica
What We Already Know
From 1994 until 2007 Charles Foerster has been the primary investigator of the Baird's Tapir Project in Costa Rica. He has laid the base work of our tapir knowledge and allowed us to ask more in depth questions about the tapir involvement in the ecosystem. Chalrie has been studying the population dynamics of Baird's tapirs in Costa Rica's Corcovado National Park. He has been monitoring the population via radio telemetry and direct observations to measure the following:
Reproductive Rate
Bairds Tapirs have offspring about every 20 months. The babies stay with the mom for about 2 years. The gestation period of a wild tapir is about 13 months. Each baby weighs about 15 lbs.
Juvenile Dispersal Behavior
Juvenile dispersal appears to be dependent on the reproductive behavior of the mother. Offspring will stay with the mother until 1-2 months before she gives birth again. Then the offspring starts to move independently of the mom. It will, however, remaining within its maternal home range for another 2 or 3 years. Between 3 and 4.5 years of age juvenile tapirs explore territories outside of the parents' range. Finally, between 4.5 and 6 years of age the juveniles move completely away to establish their own territory. To date, six juvenile tapirs have been monitored during the dispersal process. Four females dispersed an average of 18 km from their original home ranges (range: 5-30 km). One male has traveled 16 km and another 5 km. However, these males have not yet become completely established and may disperse to different locations.
Offspring and Adult Sex Ratios
Sixteen offspring have been born to 5 radiocollared females. The sex ratio of offspring has been 8 male, 5 female and 3 unknown. No birthing season has been noted.
Offspring and Adult Survival Rates
Offspring
| Age | % Survived |
|---|---|
| 4 months | 100% |
| 1 year | 91% |
| 2 years | 86% |
| 3 years | 67% |
| 4 years | 50% |
| 5 years | 33% |
Adults
- Female in 2000: Cause of death possibly old age
- 2.5 year male: Fell in canyon
- Adult male 2001: Unknown cause
- Adult male 2002: Unknown cause
Home Range Sizes
Average home range size for all adult tapirs is about 100 ha. No significant differences have been noted in home range sizes between seasons or between sexes. As expected, home ranges of juveniles (average: 67 ha.) are much smaller than adults.
Population Density
Based on adult home range size alone, the population density of tapirs in the Sirena area is estimated at 0.88 tapirs/km2. However, when home range overlap is considered, the density estimate increases to 2.54 tapirs/km2. The population needs to be monitored for more time to increase our data set.
Conclusions
The results of this study can be directly applied to the health assessment of other tapir populations and will influence new and existing conservation programs such as reintroduction, translocation, and the designation of new protected areas. In addition, we are collecting data on of site-specific parameters (home range size, habitat use, etc.), which will be vital for management plans for tapirs in Corcovado.