Table 3. Cohort life table for the Manu giant otter population, 1991 to 2006 cohorts (excluding 1997 and 1998).
x (Age) | Nx | mx | Sx | lx | lxmx | xlxmx | Ex |
0.5 | 177 | 0.00 | 0.63 | 1.00 | 0.000 | 0.000 | 3.49 |
1.5 | 111 | 0.00 | 0.80 | 0.63 | 0.000 | 0.000 | 3.97 |
2.5 | 89 | 0.00 | 0.71 | 0.50 | 0.000 | 0.000 | 3.71 |
3.5 | 63 | 0.05 | 0.63 | 0.36 | 0.017 | 0.059 | 3.83 |
4.5 | 40 | 0.63 | 0.78 | 0.23 | 0.141 | 0.636 | 4.45 |
5.5 | 31 | 0.97 | 0.81 | 0.18 | 0.169 | 0.932 | 4.45 |
6.5 | 25 | 1.04 | 0.92 | 0.14 | 0.147 | 0.955 | 4.28 |
7.5 | 23 | 1.17 | 0.74 | 0.13 | 0.153 | 1.144 | 3.57 |
8.5 | 17 | 1.76 | 0.82 | 0.10 | 0.169 | 1.441 | 3.47 |
9.5 | 14 | 2.00 | 0.64 | 0.08 | 0.158 | 1.503 | 3.00 |
10.5 | 9 | 2.11 | 0.78 | 0.05 | 0.107 | 1.127 | 3.11 |
11.5 | 7 | 2.43 | 0.86 | 0.04 | 0.096 | 1.105 | 2.71 |
12.5 | 6 | 1.67 | 0.50 | 0.03 | 0.056 | 0.706 | 2.00 |
13.5 | 3 | 2.33 | 0.67 | 0.02 | 0.040 | 0.534 | 2.00 |
14.5 | 2 | 1.00 | 0.50 | 0.01 | 0.011 | 0.164 | 1.50 |
15.5 | 1 | 2.00 | 0.00 | 0.01 | 0.011 | 0.175 | 1.00 |
16.5 | 0 | 0.00 | 0.00 | 0.00 | 0.000 | 0.000 | 0.00 |
x(Age) = age interval (starting at 0.5 yrs which is when cubs are first censused), Nx = number of individuals per age class, mx = fecundity (half number of offspring born to parent aged x), Sx = age specific probability of survival to following year, lx = probability of survival from birth to age x, lxmx = average number of offspring born to female at age x (age specific contribution to reproduction), xlxmx = mother’s age when each offspring was born, Ex = life expectancy (average lifespan remaining for an individual of age x).