Deer Diary

The autumn rut is my favourite seasonal event on Glengorm.

I can categorically tell you that nothing else – and I mean nothing – will get me springing out of bed at 5:30am.

Last year was the first occasion that I lead groups out to watch the stags; in all honestly, I was quite unlucky. The deer were slow to get going, and for almost a week of “prime rutting time” I despaired of finding any!

The 2013 rut was preceded by an exceptionally cold winter and a slow growing season for our vegetation. Though photoperiod [how many hours of daylight there are] is the main driver for rutting behaviour, it seems reasonable to suppose that a difficult cycle might put the deer behind schedule.

This time, however, they are right on cue. Alex and I were up bright and early to locate the stags.

Walking around in the pitch-black on Glengorm is a strangely soothing experience. No birds sing, no wind stirs the larch trees and only the distant boom of breaking waves spoiles the silence. That, and the baleful roaring of our stags.

Once upon a time Red deer were forest dwellers. Since the vast majority of Britain’s ancient tree cover has been removed, we are now more used to seeing them in the open.

The vocalizations that Red deer produce during the breeding season are designed to penetrate thick cover. “Roaring” carries well because the long soundwaves are able to diffract around obstacles such as trees. This differs from similar species such as Elk, which emit a higher frequency “bugling” call and prefer forest edge habitat.

Male red deer call throughout the night during the rut, and often during the day too. All of their energies are devoted to breeding behaviour; individuals can lose up to 20% of their body weight. Some will die from exhaustion, or be unable to recover condition before the cold weather of winter breaks. 

If your day needs a comedy injection, google bugling Elks and marvel at how girly they sound!

Our Red deer stags are anything but girly. If you didn’t know what was out there, you could be forgiven for thinking that our forest was full of velociraptors. The quality of the call varies based on what message the stag is trying to deliver. Mostly, it is like a long, loud snoring burp. I have been accused by my beloved of producing similar noises from time to time.

Stagsroar for several reasons: to indicate their size and vigour [to both other males and hinds], to challenge a competitor or to reinforce a victory.

As we entered Sorne forest, it was clear that there were stags both in and out of the tree cover. We continued through the gloom and emerged by Baliacrach. Dim shadows could be seen moving along the ridges against the lightening sky, and at least six animals were roaring across the glen. The wind seemed changeable; this made the task of choosing a route difficult.

Red deer rely heavily on scent and hearing to monitor their surroundings. Though they are flighty at all other times of year, massive increases in testosterone levels [1000 x the resting level – yikes] can make the stags belligerent and unpredictable. From late June, their internal reproductive organs undergo histological changes in preparation for breeding. By mid September, their “accessory” reproductive organs [use your imagination] have increased considerably in size, as has the girth of the animals neck. Oh, and did I mention the antlers? Made of bone thicker than my wrist with up to eight forward facing spikes on each side?

Basically, it is in the interests of your longevity not to meet 190Kg of antler-swinging sexual frustration head on.

With that in mind we headed off through the darkness towards the deer. We had holding grounds from the previous year in our sights, so cut through the ruined houses to a five bar gate. We moved quietly, trying not to rustle clothing or vegetation.

At my immediate left, there was a sharp bark. We froze. It was still too dark to see the animal, but we could both hear hoofbeats traveling away from us. Ahead, around five stags were calling from the ridge. We passed through the gate and agreed that it must have been a lone hind on her way to the roaring males. We were aiming for a small patch of trees that would provide cover when dawn came. Right behind us, there was a gut churning bellow.

One of Glengorm’s young stags

Red Deer Stag [close]

Alex and I slid on our bellies into one of the black houses and peered back towards the gate. Standing at it was a sizable stag. It was far too dark to see more than his silhouette, but he was rubbing his nose along the bars where we had climbed over. He was less than 20m away, but thankfully on the other side of the fence. The fence was no real barrier to him of course; but I had the feeling that without it, he might have wandered closer.

Each antler bore at least six tines [points] and the stems were well shaped and solid. He kept sniffing the places where our scent was left, becoming increasingly agitated. Alex and I mouthed expletives to one another and flattened down behind the stones.  The stag stood squarely, letting out a series of terrifying roars. From belly height, he looked exceedingly tall. These roars had a more guttural quality than those of the surrounding stags, and I am quite sure they were being delivered for our benefit.

At such proximity, the sound seemed to vibrate inside our chests. We could smell him. The weird bluish light of dawn was gathering, and against it, a pocket of hinds could be seen watching from the next rise. It started to rain. Eventually our male joined his harem; drifting off towards Balimeanach.

Red Deer Hinds

These two hinds [and calf] are part of a 22-strong harem belonging to “Mr Big” – the largest individual currently near An Sean Dun. 

Alex and I let out a joint sigh of relief. When I walked back past the gate later on, I could see huge hoof slots in the soft ground. If it hadn’t been so dark, I’m quite sure he would have seen us crouched behind the wall.

I continued alone towards An Sean Dun, where the main activity had been last year. Using vegetation as cover I was able to pick out at least four stags – some with hinds – roaring above Mingary.  More were calling from the Quinish forest, though I was not high enough to see them in the clearings.

As first-light brightened into morning, most of the master stags left for cover. Younger animals, hoping perhaps to steal a chance mating, loitered around the holding grounds. The rain was persistent, and they hunkered down in the bracken until just the tips of their antlers were visible. Every now and then they would rise to spray urine or to call a couple of times. I stayed with them for an hour, before distant gunshots sent them packing.

All in all, it was worth getting up for.

Stephanie Cope

Glengorm Wildlife Steward

 

Butterfly Conversation

Looking at enlarged images of moth genitalia might not strike you as a recipe for a great weekend. As a hobby, peering at moths’ bottoms enjoys limited appeal. Activities such as knitting are generally considered more popular and/or socially acceptable.

However. Faced with a room of thirty delegates – some from as far away as Serbia and Japan, I was forced to admit that there must be something in it.

The International Burnet Moth Symposium brings together scientists and keen naturalists from all over the world, united by their passion for just one family of moth: the Zygaenidae.

This year, the symposium came to Mull; home to one of the most localised burnet moths of all – the Slender scotch.

Delegates arrive at the Glengorm Coffee Shop

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Glengorm hosted two days of lectures for the event, which gave me the opportunity to sit in on the presentations before showing the delegates around our own burnet moth habitat.

I admit, for a newcomer such as myself, the prospect of moth-based conversation was daunting.

Grabbing a glass of wine and thrusting myself into the An Tobar meet and greet session, I scanned for a friendly face.

Me: [trying to be cool] So, what aspect of the Zygaenidae family interests you?

Delegate: [enthusiastically] I am interested in looking at the sexual organs of the moths!

Me: <long pause as gulps wine>

Not the most promising start.

But, I later learned that studying moth-bottoms is a great way to identify new species. Let’s face it, who doesn’t want to do that?

So far, over 1,000 members have been named in this family and many remain undescribed.

The following morning, perched at the back of the Glengorm lecture area and worrying about earthly matters – such as how many clean table cloths we had spare, would there be enough scones, did anyone have special dietary requirements… I didn’t know that I was about to see the light.

I think it bears testament to the skill and infectious enthusiasm of the speakers that within five minutes, my scone was languishing, forgotten on its serviette.

Burnet moths are really very interesting.

Throw down your knitting needles. Chop up your tennis rackets. Learning about burnets is not just a hobby, but an opportunity to discover. And what remarkable discoveries there are to be made.

I learned, for example, that burnet moths thrive on cyanide. Their bold colouration [generally black with bright splodges] warns that they are distasteful and toxic. In fact, sprinkling just twenty of them on your cornflakes would kill you. So resist that temptation.

Being toxic  – and, crucially, being known to be toxic (!) reduces the chances of you being eaten.

In burnets, hydrogen cyanide is made safe by adding a sugar group to create a cyanogenic glucoside. This changes the properties of the compound and makes it safe for the animal to store within its tissue.

If the tissue of the moth is damaged by an attacker, a special enzyme is summoned to snip away the sugar group – releasing hydrogen cyanide like an angry Jack Russel.

Burnets absorb the components of this toxic substance from their food plants. Nothing new here. But, sneakily, they are also able to synthesise cyanogenic glucosides within their own bodies; independent of any potential plant source.

If – during the throes of passion – my partner presented me with a love token of hydrogen cyanide, I’d probably call the police. But female six-spot burnet moths welcome this nuptial gift with open… er, legs… [they don’t have arms!]

Females will actively assess a male’s fitness based on his ability to provide cyanogenic glucosides; even creating a cloud of mixed cyanide and pheromone “perfume” to let passing males know when they’re in the mood. Perhaps this is the equivalent of giving diamond cufflinks, with the aim of receiving a proportionately more expensive necklace in return?

Clearly, these compounds are important to the moths for defence, communication and also as a store of sugar and nitrogen. Thanks to Mika Zagrobelny for a fascinating presentation about her research in this area, which I was thoroughly intrigued by.

Another thing that impressed me about the zygaenidae is their extraordinary beauty. I know I will be unpopular for saying this, but us Brits have been short changed. Our zygaenidae – lovely as they are – represent variations on a theme of dusty black, red and metallic green in Foresters [but we don’t have those on Mull].

Venture out of the UK and things get pretty wild. We’re talking mimicry complexes, brightly coloured abdomens and anal plumes. Even a dash of yellow and orange – heaven forbid. Gerhard Tarmann and Axel Hofmann [presenting work on American and African groups respectively] have done much to broaden my lepidopteran horizons.

Axel’s outstanding macro photographs revealed an abundance of colour and texture that I had hitherto been ignorant of. I also enjoyed his lively account of conducting field work: split between ferreting about in bushes looking for moth larvae, and smuggling a burgeoning collection of flora and fauna into nice South African hotels. Not to mention the urgency of identifying rare moths in the presence of Giraffes, which were probably eating them as fast as he was finding them. 

I’m pleased to say that my first impression of what moth enthusiasts are “like” has proved to be accurate. My type specimen was, of course, Alan Skeates.

Dr Tom Prescott talks to the group about Glengorm’s grazing regime 

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Alan is area recorder for Argyll & Bute; along with Anne Thompson and Dr Tom Prescott, Alan has been a guiding light as I navigate the unfamiliar waters of moth identification and conservation. His enthusiasm and willingness to share knowledge seem to be characteristic of his species – as is a tendency to wander off in search of moths at the very slightest opportunity [getting the group to and from the shore was a little bit like herding cats]. 

Both myself and the Nelson family were delighted to receive such positive feedback from the delegates about our burnet habitat. Though we’re new to the game and don’t always get it right, it’s good to know that we’re moving in the right direction.

I was really proud to host part of the symposium on our site.

Moth on, everyone.

Stephanie Cope

Glengorm Wildlife Steward

Delegates enjoy some unexpected sunshine as they examine our species-rich grassland!

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