Roe Deer - A local success story

 At the outset of lockdown, I spent my 1 hour of exercise time down the mill on my patch and set up a camera on what I call the bridge. It was over these few weeks that I started to see more and more Roe Deer, in fact, it appeared that they had now become residents on the site.

The area is perfect for Roe Deer. I am used to seeing Roe Deer in woodlands. Around here I have only ever seen them in Warwick Castle Park when I was doing Heronry Census work. My patch is not heavily wooded but it does have a large stretch of scrubland that connects to the railway line. Railways are great conduits for deer to move along and why there are Muntjac in Priory Park in the middle of the town.

Throughout March 2020 I saw small herds of between 3 and 4 individuals some of which were picked up on my main camera. As you can see from the graph below this camera picked solo visits as early as 2015 but it was in 2020 that they started to be seen more regularly. The graph shows the trend as an index of Relative Abundance. This is a function of how many times a Deer is seen and in what number.

It shows a general increasing trend with 2020 being a particularly good year. In both 2020 and 2021, they bred on the site. 

At present, I most regularly see three individuals. An adult buck with antlers, a young male with only pedicles and a female.

The dominant buck is quite bold. The antlers are not fully grown yet, they can reach 30 cms in length and have up to three tines (points). Full-sized antlers do not grow until 3 years old, so it is possible this buck is around 2-3 years old.

Here you can see the Buck with his Antlers in Velvet in January

When not in velvet the full antler set will look like this.

The young buck is possibly last years kid, pedicles tend to develop at 3-4 months and his seem well developed but not enough yet to start growing antlers although these could be the start of his new regrowth

In this image, you can clearly see the 'buds' of new antlers coming through

Roe deer do not form large herds, they prefer small family units or to be solitary. I noticed that once the Kid is born the buck tends to not be seen with the Doe and Kid until the autumn when the family group seems to reform.

The female in the winter can be identified by the anal tush of hair,

The annual cycle as recorded by otter cam, which points across a well-liked rest area can be seen below. 

It shows that they are most active at that site in October, interestingly according to the literature this is the time of fewest reports however this I think is an artefact of using a Trail Cam rather than visual sightings. The distribution of sightings on this camera indicates that the deer are moving into and out of the area. The peak in July coincides with the rut.

Reproductively Roe Deer exhibit embryonic diapause meaning that although mating occurs in July/August the egg only implants in December. Therefore young are born in May/June when the vegetation is high and there is plenty of food. Twins is a common occurrence for Roe does but I have only recorded single kids. This could be because the habitat is sub-optimal or there is an element of postnatal predation from the foxes.

Using data from both the main cam and otter cam I have looked at when they appear most on camera. This graph indicates some level of activity but should be considered with caution.

The graph suggests that the deer are most active in mid-morning and mid-afternoon. This counters the literature that shows that their peak activity is at dawn and dusk. This difference can be explained when it is understood that both camera locations are in quiet well-covered areas. It is in these spots that the deer have chosen to rest up during the day. Whilst they may not rest or sleep, although that has been observed they do seem to like spending a lot of time just chilling there. They often spend between 30 mins to an hour quietly browsing or drinking.

Roe Deer are very well camouflaged and more often than not they see me long before I see them. They are amazingly agile and can disappear into the undergrowth very quickly and for large animals, the largest in this area they do so remarkably well.