woodpecker: Survirvorship data for adult and juvenile Acorn Woodpeckers
In popbio: Construction and Analysis of Matrix Population Models

Description Usage Format Source References See Also Examples

Number of juvenile and adult Acorn Woodpeckers and survival in the Water Canyon, New Mexico population, reconstructed from Stacey and Taper (1992).

1	woodpecker

A data frame with 18 rows and 4 columns

rate: Adult or juvenile stage
year: Year
start: Total number of starting individuals
surv: Number surviving to spring

Stacey, P.B., and M. Taper. 1992. Environmental variation and the persistence of small populations. Ecological Applications 2: 18-29.

Akcakaya, H. R. 2002. Estimating the variance of survival rates and fecundities. Animal Conservation 5: 333-336. Kendall, B. E. 1998. Estimating the magnitude of environmental stochasticity in survivorship data. Ecological Applications 8(1): 184-193.

Kendall and varEst

woodpecker
x <- subset(woodpecker, rate == "adult")
plot(x$year, x$start,
  type = "o", pch = 16,
  ylab = "Number of adults", xlab = "Year",
  main = "Acorn Woodpeckers in Water Canyon"
)
## stage-specific survival rate
x <- aggregate(
  list(Nstart = woodpecker$start, Nsurv = woodpecker$surv),
  list(stage = woodpecker$rate), sum
)
x$survival <- x[, 3] / x[, 2]
x

    rate year start surv
1    juv   75    59   33
2    juv   76    22   14
3    juv   77    43   13
4    juv   78    42   17
5    juv   79     1    0
6    juv   80    48   18
7    juv   81    39    7
8    juv   82     8    2
9    juv   83    25   11
10 adult   75    46   24
11 adult   76    46   31
12 adult   77    40   28
13 adult   78    51   19
14 adult   79    52   28
15 adult   80    32   22
16 adult   81    46   30
17 adult   82    49   24
18 adult   83    35   21
  stage Nstart Nsurv  survival
1 adult    397   227 0.5717884
2   juv    287   115 0.4006969