Fledge Date data may be important for investigating relationships between nesting success and environmental variables. These data
in the NestWatch dataset are provided by participants, and the input of these dates may be overlooked by the participants. If not explicitly
provided by the participant, fledge date may be estimated based off hatch date or first lay date. This function checks, in order, if the nest
fledged successfully, and if a Hatch.Date was recorded or then if a First.Lay.Date was recorded. If these requirements are met, the function
uses user-input nest phenology time frames to estimate fledge date. Estimated dates are denoted with a 1 in data$Fledge.Date.Estimated.
Arguments
- data
dataframe; A dataframe containing merged NestWatch attempts and visits data.
- phenology
dataframe; A dataframe one row of phenological data for each species to be estimated. Data columns as follows:
Species: Species Codes for each species to be estimated.Clutch.Size: Average clutch size for each species.Eggs.per.Day: Average number of eggs laid per day by each species.Incubation: Average number of days spent in incubation (days between clutch complete and hatch).Nestling: Average number of days spent in nestling period (days between hatch and fledge).
- output
character; An optional character string to custom name the output dataframe
Details
Precision of the fledge date estimates depend on what data is used to estimate the values from (and if those values are estimated). Users should consider if they want to estimate fledge dates based on estimated hatch or lay dates. The function estimates fledge date by counting forward from the hatch date (if available) the average number of nestling days (provided by the user). If hatch date is not available, the function estimates fledge date based on first lay date, countersign forward the number of egg-laying-days based on clutch size (if available, or user-provided average clutch size) and eggs-per-day of the species.
Examples
# Simplified NestWatch data with missing data
# All fledge dates if nest fledged (Outcome = s1) should be 2024-06-03
# Note Attemp.ID "4" failed to fledged (outcome = "f"), so a fledge date is not estimated
data <- data.frame(Attempt.ID = c("1", "2", "3", "4"),
Species.Code = rep("carwre", 4),
First.Lay.Date = as.Date(c("2024-05-01", "2024-05-02",
"2042-05-01", "2024-05-01")),
Hatch.Date = as.Date(c("2024-05-21", NA, NA, "2024-05-21")),
Fledge.Date = as.Date(c(NA, NA, NA, NA)),
Fledge.Date.Estimated = c(NA, NA, NA, NA),
Clutch.Size = c(NA, 3, 4, NA),
Young.Total = c(4, 3, 4, 4),
Outcome = c("s1", "s1", "s1", "f"))
# Create phenology dataframe
phenology <- data.frame(Species = c("carwre"),
Clutch.Size = c(4),
Eggs.per.Day = c(1),
Incubation = c(16),
Nestling = c(13))
nw.estfledge(data = data, phenology = phenology)
#> ... Estimating fledge dates, this may take some time ...