Table 4. Model parameters and their sources, used for population viability analyses (Vortex software, Lacy 1993) of the platypus population on the upper Shoalhaven River.
| Category | Parameter | Value (sensitivity analysis) | Source of life history informationa |
|---|---|---|---|
| Dispersal settings | Min age at dispersal | 1 | Shoalhaven |
| Max age at dispersal | 15 | Shoalhaven; Serena et al. 2013 | |
| Sex biased dispersal | Both | Shoalhaven | |
| Dispersing adult males | 26% | Shoalhaven | |
| Dispersing sub-adult males | 38% | Shoalhaven | |
| Dispersing juvenile males | 55% | Shoalhaven | |
| Dispersing adult females | 14.50% | Shoalhaven | |
| Dispersing juvenile females | 15.40% | Shoalhaven | |
| Survival of dispersers | 100% (0–100%) | Unknown | |
| Reproductive system | Type of mating system | Polygynous | Grant 2004 |
| Age of first offspring for females | 2 | Grant 2004 | |
| Age of first offspring for males | 2 | Grant 2004 | |
| Max age of reproduction | 21 | Shoalhaven | |
| Max (average) no. of progeny/year | 2(1.5) | Grant 2004 | |
| Males at birth | 50% | Grant 2004 | |
| Reproductive rates | Females in the breeding pool | 62% | Grant 2004; Serena et al. 2013 |
| Males in the breeding pool | 38% | Grant 2004 | |
| Mortality rates | Female mortality ≤1yr (juvenile) | 73%, (71%)b, (0–100%) | Shoalhaven |
| Female mortality >1yr (adult) | 24%, (11%)b, (0–100%) | Shoalhaven | |
| Male mortality ≤1yr (juvenile) | 87%, (77%)b, (0–100%) | Shoalhaven | |
| Male mortality 1–2yr (sub-adult) | 62%, (43%)b, (0–100%) | Shoalhaven | |
| Male mortality >2yr (adult) | 43%, (23%)b, (0–100%) | Shoalhaven |
aShoalhaven refers to data collected during this long-term study.
badjusted mortality estimates based on estimated residency rates.