An example data set for estimating fatalities from a concentrating solar-thermal (power tower) generation facility.
The simulated site consists of a single tower generating approximately 130 MW. The tower is surrounded by a 250 meter radius circular inner field of heliostats, searched on a weekly schedule. From the inner circle, 18 concentric rings of heliostats 50 meters deep extend to the boundaries of the simulated site. Rings are subdivided into 8 arcs each, with arcs 1-8 immediately adjacent to the central circle. Arcs are search using distance sampling techniques on a weekly schedule, with 29 arcs searched per weekday.
There are two sources of mortality simulated: flux and non-flux (collision or unknown cause).Flux carcasses are generated (weibull) about the tower, with 5% to be found in the outer field. Non-flux mortality is assumed uniform across the site.
The dataset consists of five parts: Data on carcass observations (CO) from inner and outer heliostat searches, field trials for estimating carcass persistence (CP) and searcher efficiency (SE), search schedule (SS), and density weighted proportion (DWP) of area searched at each turbine (which is an area adjustment factor to account for incomplete search coverage).
solar_powerTowersolar_powerTower is a list with 5 elements:
SESearcher efficiency trial data
CPCarcass persistence trial data
SSSearch schedule parameters
DWPDensity weighted proportion of area searched
COCarcass observations
$SE is a data frame with each row representing the fate of a single
carcass in the searcher efficiency trials. There are columns for:
Season"winter", "spring", "summer", or
"fall"
Size"bat"; or "lrg", "med", or
"sml" bird
Fieldindicates carcass placed in inner or outer heliostat
field, with levels "inner" or outer.
"Search1",...,"Search5"fate of carcass on the 1st, 2nd, 3rd,
4th, and 5th search after placement. A value of 1 implies that a carcass
was discovered by searchers, 0 implies the carcass was present but not
discovered, and any other value is interpreted as "no search" or
"carcass not present" and ignored in the model. In this data set,
NA indicates that a carcass had been previously discovered and
removed from the field. A user may use a variety of values to
differentiate different reasons no search was conducted or the carcass
was not present. For example, "NS" to indicate the search
was not scheduled in that location at that time, or "SC" to indicate the
carcass had been removed by scavengers prior to the search.
$CP is a data frame with each row representing the fate of a single
carcass in the carcass persistence trials. There are columns for:
cpIDunique ID for each carcass
Season"winter", "spring", "summer", or
"fall"
Size"bat"; or "lrg", "med", or
"sml" bird
LastPresent, FirstAbsentendpoints of the interval bracketing
the time the carcass was scavenged or otherwise removed from the field.
For example, LastPresent = 2.04, FirstAbsent = 3.21 indicates that the
carcass was last observed 2.04 days after being placed in the field and
was noted missing 3.21 days after being placed. If the precise time of
carcass removal is known (e.g., recorded by camera), then LastPresent and
FirstAbsent should be set equal to each other. If a carcass persists
beyond the last day of the field trial, LastPresent is the last time it
was observed and FirstAbsent is entered as Inf or NA.
$SS is a data frame with a row for each date an arc at the site
was searched, a column of SearchDates, and a column for each arc, and
one column at the end for the inner heliostat field, labeled center.
In addition, there is a column to indicate the Season. A column with
search dates and columns for each distinct area (arcs and center) searched
are required. Other columns are optional.
SearchDatecolumns of dates on which an arc was searched.
Format in this data is "%Y-%m-%d CDT", but time zone (CDT)
is optional. A time stamp may be included if desired (e.g.,
2018-03-20 02:15:41). Alternatively, \ can be used in place
of -.
Season"winter", "spring", "summer", or
"fall" to indicate which season the search was conducted in.
Season is optional but may be used as a temporal covariate for
fatality estimates.
$DWP is a data frame with a row for each arc and columns for each
carcass size class (labels must match those of the class factors in the
carcass observation file). Values represent the density-weighted proportion
of the searched area for each size (or the fraction of carcasses that fall
in the searched area). In this example, within the inner field (center)
observers are unobstructed in ability to discover carcasses, for a DWP of 1.
In the outer heliostat field observers walk along transects separated by 50
meters, but the entire area is surveyed, so DWP = 1.
Unitunique ID for each arc, plus one labeled center
for the inner heliostat field. IDs match those used in the $CO data
frame and the column names in the $SS data.
batDWP associated with size class Bat
smlDWP associated with size class Small
medDWP associated with size class Medium
lrgDWP associated with size class Large
$CO is a data frame with a row for carcass observed in the carcass
searches and a number of columns giving information about the given
carcass (date found, size, species, etc.)
carcIDunique identifier for each carcass.
Unitidentifier for which unit the given carcass was found
at: "arc19", "arc65", etc, for arcs in the outer heliostat
field, or "center", indicating the inner heliostat field.
Speciesspecies of the carcass: "BA", "BB",
"BC", "BD", "BE", "LA", "LB",
"LD", "LE", "MA", "MB", "SA",
"SB", "SC", "SD", "SE", "SF",
"SG"
Sizesize: "bat", "lrg", "med",
"sml"
Season"winter", "spring", "summer", or
"fall"
FluxAn optional field indicating whether there Was evidence
the animal was killed by flux. "TRUE", or "False".
FieldOptional indicator of whether the animal found in the
"inner" or "outer" heliostat field?
RingOptional note animals found in the outer heliostat field indicating which concentric ring the carcass was found in.
DistanceOptional note animals found in the outer heliostat field representing the perpendicular distance from the searcher the carcass was discovered at.
DateFounddates entered in the same format as in
$SS$SearchDate. Every date entered here is (and must be) included
in the search schedule ($SS$SearchDate
XDistance in meters from the Western edge of the facility.
YDistance in meters from the Southern edge of the facility.