I finally got an opportunity to put my R skills to ‘good use for society’: I visualised the numbers of kittens that were brought to our local animal shelter throughout the season, and modelled how much milk, kitten food, and foster homes are needed to take care of them .

And, oh dear, these numbers! Season only slowly starts in April-May, but then numbers rapidly take off to over 80 kittens present in the shelter at the peak of the season in July. If you know that all these kittens need to be raised by foster parents until they are old enough to be adopted, you can imagine there is a big team of volunteers needed (ideally around 25 foster families, especially in the summer months).

The animal shelter takes care of over 200 foster kittens each year (picture credit Kami St.)

To make the life of this team of kitten lovers and the animal shelter a bit easier, I visualised how much kitten food they would need throughout the season on a daily basis. Herefore I linked up the age of each kitten on each day with the average amount of milk, wet or dry food a kitten should eat at that age.

The conclusion? A stock of 231 liter of kittenmilk, over 1000 kg of dry food and around 400 kg of wet food should last them through the season, based on last years numbers.

The youngest kittens still get their milk from a bottle every few hours, day and night

Interestingly, these graphs visualise some distinct patterns within the season. Our first graph already showed three peaks: a first big one with the bulk of the kittens in July, but a clear second wave around October, and a last little bump in December.

These peaks are even clearer in the graphs of the necessary food supplies. As kittenmilk is only needed for the youngest, and wet food when they are transitioning from milk to dry food, peaks in the different food needs stand out clearly throughout the season. The youngest kittens peak in June, August and October, yet at the height of our kitten season in July, there is virtually no need for kittenmilk. At that point, the cohort of youngest kittens – which will stay longer in their foster families and now transition to wet and then dry food, are now joined by older kittens (perhaps thrown out of their homes when they are approaching the age of vaccination and sterilisation, an unwanted expense for many unvoluntary kitten owners). The result is a group of older kittens, mostly eating dry food, that are largely gone to their forever homes by the time the new wave of kittens arrives around August.

Last year’s foster kitten (left) taking care of a little fluffball from this year’s bunch

This is the first year that I have such detailed information on kittens at hand. I hope to continue monitoring this in the future however, as I am curious to see if there is a climate signal in the data. For example, this second and third bump in the number of kittens (especially visible for the milk-loving youngest ones) could relate to an increase (and delay) in the length of our summers here in Belgium. It would be fascinating to link this up to interannual variation in weather, to see if long and warm summers indeed increase the length of the kitten season at our shelter.

Freshly fed kittens, with the milk still on their noses

PS: no, this post was not an excuse to finally post some of these cute kitten pictures on this otherwise very scientific website!