Table 5. Individual parameter changes required to attain the recovery targets (Amirault 2006) for two Piping Plover population segments in eastern Canada within 5 or 10 years, based on vital rates and population growth estimated from 1998–2003. Target abundance for recovery is 52 pairs (i.e., a 126% increase from 23 pairs in 2005) for South NS (current growth rate estimated at λd = 1.0043), and 273 pairs (a 44% increase from 190 pairs in 2005) for Gulf Piping Plovers (current growth rate estimated at λd = 0.9651). These parameter changes would be required immediately in order for the population to reach the target abundance within the stated time period, assuming current growth is accurately represented by λd. Required values that are not possible (i.e., probability of >1) are indicated as NA.
| |
| |
| |
Elasticity |
Current value |
Change required |
Value required |
| |
| South NS |
|
|
|
|
| λd = 1.1771
(recovery within 5 years) |
|
|
|
| Adult survival (ΦA) |
0.7398 |
0.7324 |
+23.26% |
0.9027 |
| Juvenile post-fledge survival
(ΦJw) |
0.2602 |
0.5314 |
+66.13% |
0.8828 |
| Hatching success (h) |
0.2602 |
0.4603 |
+66.13% |
0.7647 |
| Fledging success (f) |
0.2602 |
0.6171 |
+66.13% |
NA (>1.0) |
| |
| λd = 1.0850
(recovery within 10 years) |
|
|
|
| Adult survival
(ΦA) |
0.7398 |
0.7324 |
+10.86% |
0.8120 |
| Juvenile post-fledge survival
(ΦJw) |
0.2602 |
0.5314 |
+30.88% |
0.6955 |
| Hatching success (h) |
0.2602 |
0.4603 |
+30.88% |
0.6024 |
| Fledging success (f) |
0.2602 |
0.6171 |
+30.88% |
0.8077 |
| |
|
Gulf |
|
|
|
|
| λd = 1 (stability
near current size) |
|
|
|
| Adult survival
(ΦA) |
0.7666 |
0.7331 |
+4.72% |
0.7677 |
| Juvenile post-fledge survival
(ΦJw) |
0.2334 |
0.3415 |
+15.49% |
0.3944 |
| Hatching success (h) |
0.2334 |
0.5120 |
+15.49% |
0.5913 |
| Fledging success (f) |
0.2334 |
0.7014 |
+15.49% |
0.8100 |
| |
| λd = 1.0757
(recovery within 5 years) |
|
|
|
| Adult survival
(ΦA) |
0.7666 |
0.7331 |
+14.95% |
0.8427 |
| Juvenile post-fledge survival
(ΦJw) |
0.2334 |
0.3415 |
+49.10% |
0.5092 |
| Hatching success (h) |
0.2334 |
0.5120 |
+49.10% |
0.7634 |
| Fledging success (f) |
0.2334 |
0.7014 |
+49.10% |
NA (>1.0) |
| |
| λd = 1.0371
(recovery within 10 years) |
|
|
|
| Adult survival
(ΦA) |
0.7666 |
0.7331 |
+9.73% |
0.8044 |
| Juvenile post-fledge survival
(ΦJw) |
0.2334 |
0.3415 |
+31.96% |
0.4507 |
| Hatching success (h) |
0.2334 |
0.5120 |
+31.96% |
0.6757 |
| Fledging success (f) |
0.2334 |
0.7014 |
+31.96% |
0.9256 |
|
| |
|