My house is inhabited by two cats that have raked in 561 prey items from 2015-05-05 to 2020-11-04 (span of 2010 days). For some animals, weight was measured but then I lent my precision scale to a friend and weighing animals has fallen out of habit.

Recorded composition of prey species is

species frequency
vole 166
NA 150
mouse 141
shrew 27
LBB 12
dunnock 8
mole 6
tit 6
wren 6
robin 5
sparrow 5
blackcap 4
dormouse 4
rat 4
edible dormouse 3
blue tit 2
song thrush 2
wall lizard 2
blackbird 1
frog 1
great tit 1
hazel dormouse 1
jay 1
LBM 1
mistle thrush 1
water shrew 1

where LBB is little brown bird and LBM is little brown mammal. It would appear cats have the munchies for voles and mice. They bring in “many” shrews but they rarely eat them. I’m told cats don’t have a sweet tooth for insectivorous mammals (including moles). I wonder how would they feel about bats?

Sometimes I’m able to tell the hunter that brought in the prey.

hunter frequency
NA 367
zoe 170
feliks 21
gollum 3

Zoe appears to bring in most items for me to find. Feliks may be eating them in a bush.

Below is a graph that represents frequency of discovered prey items.

Histogram of prey items. Each bar represents a bin of 20 grams.

Total mass of found prey is about 1.92 kg.

Below image shows data aggregated by week for top three prey species.

topspecs <- names(sort(table(xy$species), decreasing = TRUE)[1:3])
topspecs <- droplevels(xy[xy$species %in% topspecs, ])

tops <- split(topspecs, f = topspecs$species)
tops <- sapply(tops, FUN = function(x) {
  out <- as.data.frame(table(cut(x$date, breaks = "week")))
  out$species <- unique(x$species)
  out
}, simplify = FALSE)
tops <- do.call(rbind, tops)
rownames(tops) <- NULL

tops$date <- as.Date(as.character(tops$Var1), format = "%Y-%m-%d")

ggplot(tops, aes(x = date, y = Freq)) +
  theme_bw() +
  geom_line() +
  theme(axis.text.x = element_text(angle = 90, vjust = 0.5)) +
  facet_wrap(~ species, nrow = 1)