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The Biology of Sea Turtles, Vol. II
FIGURE 11.2 Changes in the abundance of nesting females following a 10% reduction in
the survival rate of pelagic juveniles from a simulation of a loggerhead-type life history (ASM
= 25; pelagic stage = age classes 1–9). (a) Deterministic projection. (b) Projection with random
variance added to annual survival rates. (c) Projection with random variance and a 5-year
cycle in the proportion of adult females nesting.
9000
8000
7000
6000
5000
4000
3000
2000
7000
6500
6000
5500
4500
4000
3500
3000
2500
2000
9000
8000
7000
6000
5000
4000
3000
2000
1000
0
Loggerhead type, with random variance
year of simulation
year of simulation
year of simulation
1
11
21
31
41
51
1
11
21
31
41
51
1
11
21
31
41
51
abundance (nesting females)
abundance (nesting females)
abundance (nesting females)
(b)
(a)
(c)
Loggerhead type, with random variance and 5-year cycle
in proportion of females nesting
Loggerhead type, no variance
1123 book.book Page 294 Tuesday, November 12, 2002 7:43 AM