1. Announcements HW Addendum for CONS670 Reading assignment for BSCI363

2. pop “a” pop “b” pop “e” pop “g” pop “c” pop “d” pop “f”pop “h” TIME Population Density (Ln) Mean r = 0, P(extinction) = ?

3. General Predictors of Extinction Population Growth + - Population Size Current population size

4. General Predictors of Extinction Carrying capacity / population size. Maximum growth rate. Variation in growth rate –Demographic stochasticity –Environmental stochasticity –Genetic stochasticity

5. Variation in B&D: Demographic Stochasticity “Transparent” in VORTEX Probabilistic nature of births and deaths, males and females Function of –Birth and death rates Fecundity = 0.34? –Sex ratio

6. Variation in B&D: Demographic Stochasticity Monogamy1 male1 female Polyandry> 1 male1 female Polygyny1 male> 1 female Polygynandry> 1 male> 1 female Polygamy“random breeding”

7. Variation in B&D: EV Fecundity of adult spotted owls = 0.34 In a “normal” year: 34% of adult females have 1 female offspring. In a “bad” year, EV results in decreased r: e.g., births = 34% - “x” In a “good” year, EV results in increased r: e.g., births = 34% + “x”

8. frequency X= 34% % of females producing offspring Yearly Variation in Fecundity 14 24 34 44 54 s.d. ~68% ~95% s.d.

9. AB 1 YearFecundity (%) 2 199424 3 199534 4 199614 5 199744 6 199854 7 SD= STDEV(b2:b6) Calculating S.D. from Data (> 5 yrs.)

10. ABC 1 Yearbxbx 2 199424(34-24)^2 3 199534(34-34)^2 4 199614(34-14)^2 5 199744(34-44)^2 6 199854(34-54)^2 Sqrt(Sum(c2:c6)/(5-1)) Calculating S.D. from Data (> 5 yrs.)

11. Calculating S.D. From Data (Range) Average fecundity =.34 (range.14 –.54) Calculate S.D., based on years / data points For N ~ 10, assume range defines +/- 1.5 SD. For N ~ 25, assume range defines +/- 2SD For N ~ 50, assume range defines +/- 2.25 SD For N ~ 100, assume range defines +/- 2.5 SD For N ~ 200, assume range defines +/- 2.75 SD For N ~ 300, assume range defines +/- 3 SD

12. “Last Ditch” Estimate of S.D. Where mean value (e.g. fecundity) = 34% “highly tolerant of EV” –let SD = 34%*.05 “very vulnerable to EV” –let SD = 34%*.50 “intermediate tolerance” –let SD = 34%*.25

13. Variation in B&D: Catastrophes Defined by VORTEX as episodic effects that occasionally depress survival or reproduction. Types (up to 25, start with 1) Independent causes of mass mortality. Probability based on data (# per 100 years). Loss due to catastrophe (= % surviving) 0 = no survivors. 1 = no effect.

14. Catastrophes: Harbor Seals Disease outbreaks in 1931, 1957, 1964, and 1980 1980: 445 seals out of ~10,000 died. “Few” seals reproduce J. R. Geraci et al., Science 215, 1129-1131 (1982).

15. Catastrophes: Harbor Seals Disease outbreaks in 1931, 1957, 1964, and 1980 445 seals out of ~10,000 died. “Few” seals reproduce Probability of catastrophe: –26, 12, 14 years between outbreaks –Average time between outbreaks = 17 years. –1 every 17 years or 6 every 100 years. Loss (e.g., % surviving) –9,555 / 10,000 ~ 95% –Reproduction = ? J. R. Geraci et al., Science 215, 1129-1131 (1982).

16. Catastrophes: More Info Mangel, M., and C. Tier. 1994. Four facts every conservation biologist should know about persistence. Ecology 75:607-614. –General background Young, T. P. 1994. Natural die-offs of large mammals: implications for conservation. Conservation Biology 8:410-418. –Possible reference or starting point for term-paper Access through JSTOR (www.jstor.org)

17. Aa x Where a is deleterious Homozygous recessive is lethal (Recessive Allele Model) Variation in B&D: Genetic Stochasticity Aa AAAAa a aa Presence of “a” allele decreases fitness Reduced fitness = sum of lethal equivalents (Heterosis Model)