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.

Video Catch Up

 Spring and summer are always a busy time and this year has been no different. With Otter Cam now added to my main camera processing time has increased. A weeks data can include between 200-300 video clips and images. Video clips are each 10 seconds long but that can still take awhile to process and identify the individuals shown.

This has meant that some interesting footage has been recorded but not yet put up and so this post is an attempt rectify that.

First up is a late Spring Video blog to updated the winter one I made,

Next is an update on the youngsters on the site. I had believed the Foxes had not bred this year. The dominant male, Half-tail hasn't been seen since the winter and even then looked very old and haggard. A younger slimmer Fox was seen on the site who I assumed was the offspring from last year, however to my delight a single cub has been sighted on my main camera and I suspect they are using a den site nearby, but with both my spare Bushnell trail cams out of action from water damage I can't check that.

Another of this years treats was the increased number of sightings of Roe Deer. The small herd is perhaps 4-5 strong when the dominant Buck is counted. I noted earlier in the season that one of the does was looking very pregnant and I was looking forward to seeing the fawn. Then nothing, she disappeared for several weeks and I assumed that she had had the fawn and was looking after it out in the scrubby grassland. This week however mum returned to Otter cam and I got some lovely footage of the fawn, all full of life and some nice touches between mother and child. The footage shows the fawn with still some juvenile marking, the white spots are just visible and I suspect it is about a 3-4 weeks old at this point.

Whilst otter numbers are not the same as they were last year the smaller individual is still visiting at least once a week and marking the territory, last week I caught some interesting interactions with the Otter chasing a Muntjac, it is unusual behaviour. Neither is an intrinsic threat to the other but the otter definitely wasn't comfortable with the small deer's presence

To finish up lets look at the Badgers, they have been remarkable absent from my main camera, I think their main passage route has changed and so they don't pass the camera as much as they used to. Even so I have caught the glimpse of a small individual who is probably one of this years Cubs. On Otter Cam however one of the Sows sauntered down and spent a good fifteen minutes cleaning herself and delousing. I love how they sit on their backs and scratch their bellies.

Long term camera trapping study of British hedgerow mammals. 2015-2019

I have finally finished writing up my findings from the first five years of my camera trapping project.

The study explores in detail five species - Badger, Fox, Muntjac, Grey Squirrel and Wood Mouse with some examination of trends in Roe Deer. Brown Rat, Polecat, Weasel, Rabbit and Hedgehog.

The report looks at changes in monthly, seasonal and annual abundance changes and explores the seasonal variation in activity throughout the day and an explanation of key behaviours observed.

The report concludes with an exploration of the methods used and looks at the sort of things that need to be considered when running your own camera trapping study.

The project report is available by clicking this link

Camera Update

My new camera is back up and running and this week it caught two interesting sights.

The first is a short glimpse of a Roe Deer. The first Roe Deer sighting was on the 14th May and was a doe. This week a young buck appeared on camera for a few seconds. You can briefly see the short horns.

The arrival of this species is interesting, as I stated before there aren't many habitats for Roe Deer nearby and had the individual being a female again I would have guessed that a lone individual was passing through the area but in this case the animal is definitely a different individual suggesting that there is a larger population in the area than I would have expected.

Secondly is a shot that I always hoped I might one day get. As you may have seen from other blog posts the site is blessed with a fluctuating population of Wood Mice, the numbers seem to rise and fall reflecting not only changes in weather but also predation.

I have recorded Tawny Owls on the site in the past, I have found pellets and was even lucky enough to see a youngster some years ago. The next clip is of a Tawny Owl emerging from a hunt. Obviously, in pursuit of some prey, the Owl has swooped down but become entangled in the undergrowth. In the brief footage, I do not think the owl's hunt was successful.

Camera Trapping - A review of the year.

My camera trap year runs from April to April but I thought people might be interested in some data from the last 12 calendar months.

In the past 365 my camera has been in place and recording for 335 days (92% of the year). It was activated a total of 3588 times of which 1052 were activation only's, errors or failures (29.3%).

This number of activations equates to 107,640 seconds worth of footage, that's 29.9 hours of clips to watch.

335 days equals 8040 hours and an activation by something recordable occurred 21.13 hours worth of time meaning that along the hedgerow there was an animal or me present 0.26% of the time!

The very first animal recorded in 2016 was a Wood Mouse and the very last a muntjac and fawn. They were recorded at 23.58 on the 31st December. This goes to prove that Muntjac will breed throughout the year.

Aside from myself over the past, 12 months's the camera recorded:

Wood Mice - 255 activations

Muntjac - 233 activations

Badgers - 246 activations

Foxes - 133 activations

Grey Squirrels - 312 activations

Rabbits

Brown Rats

A Domestic Cat

Wood Pigeon

Blackbirds

Song Thrush

Robin

Dunnock

Great Tit

Wren

Magpie

Pheasant

Moorhen

Jay

Redwing

The pie chart shows that the occurrence of the main species is fairly even although Grey Squirrel just edge the most populous and the Red Fox is the least.

Over the year I have caught some interesting behaviour such as identifying the badgers regular sprainting and how they forage. The squirrels have been very feisty and squabbling a lot and the fox has been quite elusive.

On the unusual side has been the few sightings of Rabbit. Rabbits used to be prolific on the site but never recorded on the camera using the hedgerow but this time over a few days individuals were sighted, possibly bucks seeking new territories.

Heres to another 12 months. I will have completed 3 years worth of data and so look out for graphs of each of the main species then.

Deer Family...

A few weeks ago my camera picked up a female Muntjac with a fawn. Muntjac are able to breed practically all year round and so this was not too surprising. This week I managed to catch the whole family.

The female was in the lead with the male with distinctive eye stripe and horns bringing up the year.

On a related note I am starting see differences in patterns between last years sightings with the camera and this years, The number of Grey Squirrel sightings is much reduced this year relating to the fact that the beech tree on which the camera is fixed to has not fruited at all and there is no ground fall beechmast.

The rabbit I caught was a one off, it was seen on that day and that day only. Its possible that this was a buck exiled from a warren and was off to find a new colony to join or found his own.

Balsam and a Cat

This week I evaluate a little experiment I undertook last year. On the patch of land I look after there is present that invasive species - Himalayan Balsam.

The pretty pink plant found along much of our water ways was introduced to Britain from India in 1839 along with Japanese Knotweed and Giant Hogweed, both of which exist on other stretches down the river,

Balsam is incredibly prolific and spread via impressive exploding seed cases. There is much debate about what to do about this species and many believe it should be hand pulled and burned. My take on it is slightly different and specifically tailored to my patch.

On my patch the balsam is a mosaic species one of many including nettles, meadowsweet, Epilobium and Purple Loosestrife. It has not come to dominant the area and exists on patches, often out competed by natives on much of the patch. It is not acting invasively here... yet. Whilst the plant itself is not favoured by many of our insects the characteristic sweet smelling pink helmet shaped flowers are adored by Bees.

With Bees suffering I find it hard to rationalise the removal of a potential food source so last year I attempted a little control method. Along the bridge path I have responsibility for the right hand side and so went in August and cut the flower heads just before they set seed. This year as you can see comparing the two sides of the path that there is much less balsam on my side than the other.

Left Side - Note the number of Balsam flowers close to the railings (Control)

Right side - note the lack of balsam close to the rails (Experiment)

Now this is not the greatest experiment I haven't quantified this in any way but it does prove to me at least that where I want to control balsam it is most effectively done by dead heading in early-mid August.

On a very separate note my trail cam has detected a new visitor to my patch - a Ginger Cat. I have had a black and white cat pass through in the past but this ginger cat with white socks spent much of Monday pottering up and down the hedge-line between 7.43 am and Mid-day. Most interestingly he seemed to enjoy a spot of Muntjac baiting.

Happy Birthday Trail Cam

It has now been a full year that my trail cam has been situated on the beech tree on my patch and what a year it has been.

It has been running 24/7 in that time with occasional breaks where the camera batteries died or I forgot to switch it back on when swapping out the camera card. Over the year the camera didn't record for 7 of the 52 weeks and in total was active for 7476 hours.

Its too early to give you a full analysis of my findings but I can give you a quick run down of facts.

In the 7476 hours the camera recorded the following animal activation's:

139 Badgers

225 Foxes

127 Muntjac

616 Grey Squirrel

354 Wood Mice

Several Brown Rats

1 Polecat !!!!!

And the following birds:
Robin
Dunnock
Great Tit
Magpie
Blackbird
Song Thrush
Pheasant
Woodpigeon
Wren
Chaffinch
Jay


Below are the up to date graphs of abundance, I will go over these in greater detail once I have had time to analyse the data but its because fairly clear that there are patterns evident I thought I would let everyone have a look.

Hello deer

Part two of my series on camera sightings, today is a series of clips on the Muntjac.

Its interesting to note that Muntjac have been seen only occasionally on the site over the past 10 years but the camera data shows that they are much more abundant illustrating how timid and cryptic they can be.

This second clip taken at the same time shows this female particularly well.

I have never seen two Muntjac together but the camera identifies at least one pair moving in and out of the area, heres hoping for young this year.

Lastly is evidence of the deer feeding on the leaves around the camera. Most earlier clips show the deer just moving through the area however eventually they started to stay longer and foraged through the leaf litter and then this winter began to feed upon the leaves.