Population Viability Analysis of the Endangered Roan Antelope in Ruma National Park, Kenya, and Implications for Management

Table 1

Biological and ecological attributes of roan antelopes used as input data in the baseline scenario to the VORTEX model. The percentage impact of catastrophes (drought, fire, and floods) indicates how much the reproduction, survival, or frequency is reduced from what typically it should be.

Demographic parameter	Value	Source/reference
Breeding age females	3 years	[7]
Breeding age males	5 years	[11]
Mating system	Polygamous	[11]
Percent of adult females in breeding pool	100%	[8]
Percent of adult males in breeding pool	30%	[8]
Maximum litter size	2 calves	[13]
Mean litter size	1 calf	[11]
Inbreeding depression		[4, 14]
Lethal equivalents	3.14
Percent due to recessive lethal alleles	50%
Reproduction active life	12 years	[11]
Age classes		[9]
Calves	0-1 years
Subadults	1-2 years
Adults	>2 years
Annual survival rates:		[8]
Calves (mean ± SD)	89 ± 2%
Subadult (mean ± SD)	92 ± 3%
Adult (mean ± SD)	79 ± 5%
Birth rate per female per year (mean ± SD)	0.45 ± 0.15	[8]
Sex ratio at birth	1 : 1	[11]
Carrying capacity (mean ± SD)	288 ± 20	[8]
Multiplicative impact of catastrophes		[8]
(i) Drought
(a) Frequency	20%
(b) Reproduction	10%
(c) Survival	15%
(ii) Fire
(a) Frequency	20%
(b) Reproduction	5%
(c) Survival	5%
(iii) Floods
(a) Frequency	10%
(b) Reproduction	0%
(c) Survival	15%