A Grey Squirrel thats a night owl?

 I am writing this blog post on a very wet Sunday afternoon. I have been lacking inspiration to post for a while now. No special creature has appeared no profound thought of ecological theory has struck. I have very much been struck in the rut of the change of seasons, the summer visitors have gone, and the winter ones seem not to be bothering to come at all this year. Last week the temperature did take somewhat of a dive, and this resulted in the return of the Marsh Tits to my patch, a small flock of Teal, a nice view of some Goosander, and a very fleeting view of an accidentally flushed Woodcock.

This past week the cold has evaporated to be replaced by rain, torrential downpours. Facebook happily reminded me that 6 years ago today we were under 6 inches of snow what a difference. I did see my first Redwings of the year, just three not the hundreds one would expect. From this introduction, you may assume that I am going to wax lyrical about climate change and the shifting of the season, but I feel I have done a lot of that already and I would imagine that most of my readers are not climate deniers. Instead, what piqued my interest were a few still shots from my main camera trap.

This particular camera trap has been situated in the same hedgerow recording 24/7 since 2015. This is my magnum opus, my long-term contribution to wildlife, and in particular mammal recording. My usual focus is on the Badgers, the local clan is seen less and less (I am very worried about them at present), but more recently the Roe Deer family and Otters have drawn my focus more. What has intrigued me most this week however is the ubiquitous Grey Squirrel.

Laying aside the obvious debate concerning its status as an invasive species, the demonic species that has devastated the native Red Squirrel, even though it is just doing its thing…survival, what drew my attention was some interesting behaviour.

It is easy to watch wildlife and become focused on the individual, websites, and books are filled with portraitures of birds and animals, and whilst delightful, I think I find the behaviour to be extra interesting. We are now into December and like I said we have had a cold snap now followed by rain. On the trail camera, I caught a few stills of a Grey Squirrel collecting leaves, it was noteworthy enough to add it… well to the notes section of my records.

Consistently for approximately an hour on the 28^th of November in the early afternoon, a squirrel could be seen collecting beech leaves and taking them up the tree. This continued across the 7^th, 8^th and 9^th of December despite the rain. This is obviously evidence that the individual is either building or remodelling its drey.

Squirrels live in dreys, collections of leaves and twigs sometimes lined with grass and moss. They are not a species that hibernate, and, in the winter, it provides, a warm refuge to retreat to between foraging expeditions. Dreys are built in the crook or v of branches in trees 2-20 metres off the ground, they appear roundish and nest-like, in fact, they can be confused with magpie nests although magpies are much messier.

Photo care of Rosser1954 on Wikimedia Commons CC-3.0 Grey Squirrel Drey.jpg

What interested me however was the timing of this event. I understand building it now, the weather has turned and the squirrel needs to shore up its existing drey or repair its old one if conditions are likely to worsen but this squirrel seems to be in quite a hurry often working in the night!

Squirrels are pretty much diurnal perhaps more active at dawn and dusk. Previous analysis of activity has indicated a rather broad daytime activity pattern on my patch. An aggregated count from 2015-2019 indicates activity occurring between 7 am and just past 5 pm so it surprised me to record the squirrel actively collecting leaves at 2.18 am, 5.40 am, 9.40 pm and 10.29 pm.

2.19 am and still collecting leaves!

A quick internet search suggests that squirrels are not nocturnal however I am one who on the whole eschews the internet as the font of all knowledge and so have fallen back on my books. My go-to bible in these situations is Harris and Yalden’s Mammals of the British Isles: Handbook, 4^th Edition.

The Grey Squirrel account is written by J. Gurnell, R.E. Kenward, H. Pepper and P.W.W. Lurz and only has a paragraph on activity in which it states that they are less arboreal than Red Squirrels. Of note is a section on communication and senses. Seeing the squirrel in the dark I was concerned for its safety. It is predated by stoats, buzzards, and foxes. I have seen a vixen carrying a squirrel back to its litter, given that its usual life strategy is based on daytime activity just how vulnerable was this squirrel? The answer it appears is very, the book details the structure of the eye drawing the conclusion that the species can see in up to dim-light so fully nocturnal activity is very risky. Admittedly they have excellent hearing but their agility on the ground and up trees is based very much on vision.

I then considered the effect of the moon; a full moon could give enough light for the squirrel however from the 7^th-9^th of December the moon was a waning crescent with only 24% illumination on the 7^th falling to just 10% on the 9^th.

I will not get a definitive answer to this conundrum, nature does what nature does and most certainly does not follow the rules of the textbook. I considered that the individual could be pregnant and was forced to build/improve the drey for that, and births have been recorded right up until the end of November. Perhaps the mild spell allowed for a late pregnancy, but this is very much on the edge.

Animal behaviour is very much a cost/benefit game, and this squirrel obviously felt the need to put itself at risk and it would not do this if not for gain, unless this is one of those individuals that shape evolution, either making a mistake that inevitably leads to its predation and the end of its gene line or the pioneer that stakes out a new niche for all its kind.

It are these puzzles that make ecology such a fascinating topic to study.

 

September Vlog

 This week I experimented with doing a vlog of my patch. A look at what is about and what is happening at this time of year.

Rewilding and Conservation

 

I am a little late to the debate stirred up by Alan Titchmarsh’s comments on rewilding. This is in part because I wasn’t fully aware of what he said and secondly, I needed time to collect my thoughts.

I first really encountered rewilding as a conservation technique or at least a progressive form of land management back in 2013 when I read George Monbiot’s book – ‘Feral’. I had been aware of the principle and had heard of interesting results in Yellowstone regarding wolves, but this was the first time I really began to delve deeply.

I am going to assume you know the principles of rewilding in this article as that will make things a little smoother, but to set the stage, rewilding is, in essence, letting ‘mother nature’ assert herself over previously man-controlled habitats.

Now it’s true that in most of the world and indeed Britain there is very little which has not been affected or changed by man. Even in the remote wilds, powerlines and litter can be spotted or planes flying above. Man of course is a part of nature like any other species, that however is a whole other philosophical debate. The question then becomes what are we rewilding to? The consensus is restoring habitats to a prehuman state say Ice Age. For Britain, that means a lot of woodland and previously extinct mammals such as the beaver, aurochs, lynx, wolves, and bears.

Let’s take a pause and look at what the argument was. Alan Titchmarsh was lambasted for stating to a House of Lords committee that rewilding is “catastrophic” for biodiversity and an “ill-considered trend”. What cheek! Alan has long graced our screens and has supported wildlife gardening in many cases. His worst crime however came from his ‘Ground force’ days which paved the way, pun intended, for gardens that did away with lawns and encouraged everyday gardeners to hard landscape.

The issue at hand here is scale, Alan was talking about the idea of rewilding gardens. Letting the grass grow long, leaving some nettles putting in a pond rather than a water feature. These elements are not rewilding they are wildlife gardening. The two have become conflated. Rewilding, natural rewilding in which land is left to regenerate itself needs space and lots of it. Only with a vast amount of space can ecosystems develop into a natural mosaic. For example, allow a meadow full of wildflowers to regenerate and it will first become scrub and then woodland. During this time its biodiversity will change, probably dropping before rising again. The grassland specialists will be replaced by woodland ones. If the area is large enough and there are enough ecosystem engineers then the grassland will regenerate in a new location, perhaps becoming ephemeral. This is the principle of succession, the way in which habitats evolve from bare rock to rainforests.

So, scale is important, gardens are just not big enough to make rewilding possible. I am not saying gardens are beacons of biodiversity. Non-native planting may be pretty, but they are not suitable for our pollinators or insects, but they are better than a concrete wasteland. A bit of wildlife gardening in each garden is a huge wealth of nature.

Part of the problem of rewilding is this concept of scale, there are very few places in the UK where projects of suitable scale are viable, the real problem of nature conservation is the limitations of reserves. I m not saying nature reserves are bad per se just that over the years they have become a limiting factor. We now have a series of isolated reserves across the country that exemplify and protect particular habitats. By their very necessity, they are managed. They are kept at what is termed in successional terms a plagioclimax a stable state of equilibrium that reflects the particular habitat or species that is desired.  This is the antithesis of rewilding; mother nature is put in halters. We have had to do this to protect rare habitats and species, but how is that working out? Reserves are sacrosanct but reflect only a tiny portion of the outdoor space and this reflection is limited. What about the less interesting habitats or less interesting species? Take, for instance, the House Sparrow or Starling, once common and now in severe decline. We are lucky in Warwick with strong numbers of both (though much fewer than in my youth) but where are their reserves and protected spaces?

This is an extreme example, but I think you catch my drift. Scattered reserves are fragile and vulnerable, cursory examination of Ilka Hanski’s metapopulation and habitat fragmentation theories catalogue this. Recent actions have been to connect reserves and work at the landscape scale, but this brings conservation into even more conflict with landowners and planners. Good work is being done by Warwickshire Wildlife Trust with the Princethorpe Woods Project and the networks in the Tame Valley, but we need more. More protection and sympathetic management across the countryside. Even the lowliest patch of scrub or nettle bed holds a level of local importance and by focusing on the special we risk dragging the common down to the lower level rather than raising them up. Rewilding plays a part in this, as with these larger networks and landscape-level approaches there is more opportunity to allow habitats to shift naturally to its successional apex.

In many respects, many reserves are examples of controlled rewilding. Over one-third of the reserves managed by Warwickshire Wildlife Trust are reclaimed industrial land. Mostly quarries, gravel pits, and railway cuttings. These sites are ripe for development and allow a habitat to be chosen and cultivated. They are flagships for renovating old sites and have worked considerably well but often tend to be wetland sites, good for visitors and waterfowl, however what of our farmland birds? Should more farmland not be bought and managed? The trust manages many excellent ancient and semi-natural woodlands and these are great but are part of the landscape, we need to secure the sections in between not just the connecting hedges.

This has turned into somewhat of a ramble but at the root of it is that nature conservation has to evolve. Reserves are a useful start; rewilding is a great tool but neither is good in isolation. Pundits like Alan Titchmarsh are not ecologists, and they have a vested interest in a particular narrative, we can’t blame a gardener for advocating for neat cut lawns and flowery beds, but we need to take direction from those that know not who say they know.

With climate change and the biodiversity crisis, I feel that we are at a crossroads. There is a need, as biodiversity offsetting takes hold and the pressures of house building increases, to start to focus on the strategic and landscape scale to protect all habitats not just the rare ones.

The Canary, the Butterfly and the Licence Plate - The decline of insects

 I have spent just under half my life visiting and recording wildlife on my patch, that’s quite a chunk of my time, about 20 years to be truthful. I am someone who likes routine, but this is more than that. This is a piece of land that I love and am in sync with. I have seen enough now to be in tune with some of nature’s cycles and realise when something is off. Some people may get bored with visiting just one spot, in fact, many birders or twitchers chase the dream birds, would I do that if I enjoyed traveling… I think not. There is something special about becoming part of an ecosystem and understanding its ebbs and flows.  Besides the site continues to amaze and surprise me.

Marbled White

Just today I was out for my normal Sunday morning visit having lamented the previous week’s lack of butterflies. Last year the farmer cut the meadow and I had predicted to myself that the loss of many of the nettle beds and more grass would result in fewer tortoiseshells but more ringlets, meadow browns, skippers, and gatekeepers. So far, this vision had not been borne out. I was beginning to think about the national insect decline. This is a national crisis affecting all of Britain. Invertebrates are an essential pillar in our habitats. They provide the bulk of the food for our nesting birds and breeding fish which in turn provide for our predators. How can we expect our declining Swifts to survive if not only are we robbing them of their nesting spaces but their very food?

To highlight this problem, I had a mini epiphany this week. It is early July and Wimbledon is in full swing. When I was a child in the late 1980s my sister and I would watch some of the matches but more often we had more fun playing our own Wimbledon in the back garden. Mum would string some wool across the garden to act as a net and we would come out on to centre court with our plastic blue rackets and our bright yellow or red sponge balls to play a few games, complete with MacEnroe-style debates regarding what was in or out and who was serious.

One of the key features of these games were the clouds of midges that seemed to hang in the air at the bottom of the garden. These were not the Scottish midges that would eat you alive but more the tiny non-descript tiny flies that as a species seemed to serve no purpose except to annoy. We would take great delight in swiping our rackets at them, imagining we were decimating their numbers like mighty warriors when in fact I doubt we ever struck one, so large were the holes in our rackets and the air pressure created. The point is that when I look at the bottom of the garden now, I find it hard to see a single simple fly. We have insects, bees, wasps other flies but in much smaller numbers. We have never used insecticides and our garden is wildlife-friendly with overgrown patches and an adequate pond so it’s not a change in the very local habitat but something wider, something national, something global.

Buglife has been assessing this problem and has just (June) released its 2023 Bugsplat survey. This innovative survey assesses the number of insects that get squashed on a number plate across a certain distance driven. This is of course a citizen science project and as such have inherent flaws in the distribution of responses. Scientifically comparing long-term trends, I wonder whether there is an effect on the change in car design and aerodynamics that might affect the data, but that’s just my analytical scientific brain working overtime. The survey now, digitized via an app, aren’t they all these days, demonstrates that the number of insects sampled on a licence plate between 2004 and 2022 is down 64%. This value backs up the more anecdotal evidence and something that for me is an observation.

Luckily my patch continues to surprise me. With most of July and August still to go it is hard for me to assess if butterfly numbers are down on my patch, but today’s survey was encouraging. The survey was done this morning following a night of rain with increasing sunshine and a light breeze, within the hour I had seen 6 Ringlets, 3 Meadow Browns, 2 Red Admirals, 3 Commas, 1 Large Skipper, 31 Large Whites, and 1 Marbled White. The Marbled White is particularly exciting. This has never been recorded at the Saxon Mill before, in fact, I have only seen this species out towards Charlecote and Stratford way in the past until this year, when I recorded one last week at Warwick Racecourse.

So what is the moral of the story, two things, I do not think I will ever get bored of my patch, it continually surprises and after 20 years I am still discovering new species, secondly, insects are suffering and insects are not the only canary in the coal mine that has become choked on the gases produced in the past few years.

The Blink of an Eye

 The lifespan of a human is perhaps 80-90 years and increasing with every generation. That's a lot of living for an organism. It's easy to forget that for most species life is much shorter and much harder. There is a rough rule of thumb that the larger the organism the longer the lifespan the graphic below illustrates this quite neatly.

There are complex ecological reasons for this involving life history strategies and energy flow but in essence, species generally exhibit one of two life strategies. Complex large animals have longer lives than smaller less complex ones. These strategies reflect two extreme modes of reproduction and survivability and can explain why and how different species behave the way that they do.

The two strategies are r and K. r/K selection was developed in the 1960s as part of MacArthur and Wilson's famous theories on Island Biogeography. The theory dictates that species have either an r or a K reproductive strategy. r-strategists are related to the rate of production of a species and so these species produce large numbers of offspring, have short lifespans, and have a low probability of survival. 

K-strategists are dictated by the carrying capacity of an ecosystem, these species have fewer young and live longer. Offspring develop slower and they tend to have higher greater parental care and therefore greater chance of survival.

All this information is pertinent at this time of year as the country erupts in a reproductive fever. Everywhere organisms are mating and having young and it is in this month that one of the organisms that typifies r-selection is abundant.

May is the time in which Mayflies emerge from our rivers in great clouds of dancing pixies. On some rivers, this display of flying mayflies is awe-inspiring but on my patch, it is somewhat subdued. It is still fascinating and this year has been particularly good. There are in fact 51 species of mayfly in the UK and they play an important role in the ecology of a river. They provide food for fish of many species as well as birds given the huge mouthfuls I saw the local Great Spotted Woodpecker taking into its nest.

On my stretch, I managed to identify two species, the Common, or Green Drake Mayfly (Ephemera danica) pictured below and Drake Mackerel Mayfly (Ephemera vulgata). These mayflies have hindwings and three tails. These species may be simple but they are an ancient species, mayflies were around before the dinosaurs, and they are a very successful species.

Most mayflies live but a few hours some as much as a day. I say mayflies, what I actually mean are the adult forms. They emerge from the water in mid-may as dull-winged insects, they then fly into undergrowth and moult again into a much brighter mating form.

The males dance above the water with females darting into the cloud to select a mate where they mate on the wing before the female descends to the water below. She will lay her eggs in the water and then exhausted collapse.

We tend to pity the mayfly's short lifespan but that is only the adult form. The eggs hatch into larvae which will spend up to two years developing on the river bed feeding on algae and vegetation. So feel a little less sorry for the mayfly, yes their appearance to us is fleeting but they in fact have a reasonable life out of sight. The paternal sacrifice of the adults feeds the bellies of fish and birds in a complexly balanced ecosystem. 

And to be philosophical for a moment a two-year lifespan may seem like a blink of an eye to us but this species has lived on earth for perhaps 300 million years whilst Homo sapiens has existed a mere 300,000 years, now who lives in a blink of an eye.

Harmony in nature?

 My long-term camera trapping project whilst giving me fascinating glimpses into animals' private lives also highlights interesting species interactions.

It is surprisingly uncommon for more than one species to appear on camera at the same time. Birds are much more tolerant of each other and so different species can be seen together but mammals are much more wary and when two species do meet it is interesting to see what happens.

For the last few weeks, I thought I had identified two different foxes using the site based on ear patterns. I had 'Speckles' who had orangey specks to the backs of their ears and 'Black-Ears' an individual with completely black ears. It turns out this wasn't as good an identifier as I thought. Two foxes were sighted this week, both with black ears. The interaction between the two was interesting, the last interaction was a post-aggression bout of gekkering but these two individuals seemed much more comfortable with each other.

What was more interesting was the presence of a male muntjac. This youngish male is missing one antler and is present whilst these two foxes are. It seems unconcerned by them but was still wary, you can see it keeps an eye on where they are but is relaxed enough to settle into some grooming. 

This may seem like unusual behaviour for predator and prey but in actual fact, it is unlikely that any fox would actively hunt an adult muntjac. The risk of injury would be too great for a fox to risk, one wrong move and its ability to hunt later could be impaired. Unlike wolves, foxes are not pack animals. They can exist in extended family groups and it's common for two vixens to work together to raise young but this never extends to cooperative hunting. A pair of foxes would have more chance of bringing down a deer but this has never been a hunting strategy. Foxes fill a niche in which they scavenge and prey on rodents and birds, pigeons and pheasants being a favourite.

This clip shows three individuals sharing the same space and time, it's a rare illustration of a certain harmony in nature, a knowledge of eaches position in the ecosystem, and an awareness of the nature of the other.  It is sometimes too easy when wildlife watching to focus on the individual but a better understanding is gained when you consider the individual or the species in the context of the interconnectedness of the habitat. Nature is wonderful and much of that wonder comes from the complexity, thousands of species in an ecosystem reliant on one another woven into an intricate pattern of inter-reactions.                                                   

Habituation

Most animals and people in fact learn via habituation or perhaps more accurately are trained by habituation. Scientifically habituation is the diminishing of an innate response to a frequently repeated stimulus. Think of it a little like the saying 'familiarity breeds contempt' or rather in this case familiarity makes the response more comfortable. In human psychology habituation is fundamental to cognitive behaviour therapy (CBT), something I am accustomed, habituated to you might say. When tackling my anxiety over travel my CBT had me taking weekly train journeys in incrementally larger distances until travel by train was normal.

 Habituation has been used throughout human history to domesticate animals and it is something I have used send times over the years in my wildlife watching. When I first started regular patchwork back in 2001 my local swans were ZNY and VGY, over the space of many years I got to know this pair very well, and importantly they me. I saw them every week and each week I would have some bread or seed to feed them. Out of habit, I would make a whistle when I fed them and they soon associated that sound with me and food, pretty soon I did not need to whistle and they would come over as soon as they saw me. 

The habituation slowly developed into something more than cold psychology, we gained mutual trust and respect. In the end, before ZNY died and VGY moved off with a new mate, they were comfortable enough with me to allow me to sit alongside them and would even bring their cygnets over to within arms reach and be quite relaxed. I learned how to read their moods and behaviours and likewise, they learned my hand signals that denoted a warning for when I would move or stand or my splayed-out fingers to demonstrate I either had no food. This was a very special bond that I have never managed to replicate with the other swans in the area. 

I talk about habituation today because I think that the roe deer are beginning to habituate to me. The two young does have been on my patch their entire lives and just as the local foxes, badgers, and muntjacs are a normal sight, so I believe I have become to them. I am getting pretty good at guessing where on my patch they will be on any given day, nevertheless, they are always one step ahead of me. Their senses are keen and their camouflage nearly perfect.

 This week on my survey I decided not to be too stealthy, they knew I would be there long before I saw them and I wondered if acting stealthy might make me seem more predatory. I have found this trick useful in the past. I try to appear docile and part of the wildlife, I make my movements hesitant and wary I don't make eye contact, something that instantly screams predator. I even try to respond to alarm calls. If a blackbird or great tit alarms I will freeze and look and scared. I try everything I can to seem like one of them. This worked quite well. I spotted the roe deer lurking in the undergrowth they loped away but I didn't follow. Instead, I sat for a bit and then went on. When next I saw them they were standing in the undergrowth watching me, I avoided eye contact and moved further away. Keeping my moments slow I took a few photos. As they moved off again I followed slowly keeping a distance and again taking a seat on a gate feigning disinterest in them. They quickly settled down and whilst they were still wary of me their body language was more relaxed and as they moved they did so in a less panicked state. Although they weren't comfortable enough to stay in my presence they left at a slow pace and not due to any action of mine.

This was the most natural connection I have had with a roe deer and it stemmed from them becoming used to me - habituated and me becoming used to them - habituated. The danger of habituation is that they become too familiar with people, its why many rescue centres try to handle animals as little as possible and will use release pens.