Sunday, 11 December 2011
Territory size of a Sussex big cat/600+ square km
26 sightings this year in 21 parishes add more weight to gaining more of an understanding of the yearly range of a typical big cat in Sussex.I say typical because it is really a study of a large part of West Sussex in particular 4 big cats 1 of which is far larger than the others and has several defining features that set it apart from the others ,this has made it possible that when a sighting comes in i can usually differentiate this cat from it,s nearest neighbours,added to this i work on the farm where this cat has been very active at times and know all the surrounding country fairly intimately.In this way when sightings come in they are plotted on a map together with the habits observed by the witnesses.Big cats act differently to each other in their behavior,for example when seen one might slink away while another typicaly looks at it,s observer then runs hell for leather away to cover.Carcases found too have similarities and differences depending on which cat has killed it so a pattern starts to emerge on where which cat is at certain times of the year and what it is feeding on,paw prints too ,whilst they are found far less frequently,are as distinctive apart as human fingerprints.Colour wise all these 4 cats are black but the shapes of their bodies can be described differently however it must be remembered that body shape of a cat changes depending on what it,s up to.A friend who lives not too far away has photographed this big cat the results of which i have published on bigcatsinsussex.co.uk and has been now used in the recent,highly acclaimed big cat book by Rick Minter,in other words people from up and down the country have looked at the picture and thought it to be the genuine article.So,we have had the best chance for years to guage the territory size of this,one the countys biggest big cats.....
A lot of the data already gathered has been published for public perusal here on these blogs but also on the website with the exception of sensitive material and sightings evidence that is location private for one reason or another like the farmer concerned wanted his place kept out of it.I have attempted to analyse this data as thoroughly as i can to produce a series of findings which can be repeated elsewhere dependant on habitat type and prey numbers.What is quite clear is that the findings so far confirm some previous data inputs and surprise or turn on their head others.
To start with as a general rule of thumb a big cat will be seen in an area of a clump of parishes once at a certain time of year then maybe again very often a month later then possibly,if the hunting is good,a couple of months after that or instead may visit several months later.This has been noticed over the years.In other words it will only either actively hunt or pass through 2 or 3 times a year but usually in the same seasons.This has been observed by myself and others on countless occasions to be now almost a rule of thumb.Big cats are not scavengers but hunters and to survive can only predate loosely in any given area before their prey gets wise,coupled with this they have competition with others like foxes who share at times similar hunting techniques and prey like rabbits and foxes are often well established in the areas that a big cat may be in.As regards to deer they are usually the younger ones taken,first year fawns,not the adult roe and so there,s a limited number of these taken.So we can see here at a glance that a big cat would need a much more vast and varied habitat than it,s most similar rival a fox.
With every rule of thumb in nature there is an exception and our principal cat of study shares this with the others in that it has an area/s where it,s seen far more regularly than in other places.It has areas that are the edge of it,s range and on reaching these it is forced to turn in for geographical reasons.For our cat it,s the major coastal,downland towns and it,s here that it,s seen more regularly in fact 12 of these clumps of sightings where it,s been seen this year have been at these places but i feel it,s a mistake to regard them as a pattern that is repeated elsewhere but the data has just not come in,in other words big cats in Sussex are repeatedly being seen at turning points of their range whereas at other points they are habitually seen/frequent much less.A breakdown of these turning points have seen the cat hug the coastal downs for it to then turn inland and head for the general Weald area.The downs as a whole is mostly open,as the photo above shows,but has pockets and in some places has clumps of cover like scrub extending into very extensive woods,it has been noted to hunt successfully on certain parts of the downs but spends a larger proportion of it,s time on the Weald where prey numbers and hunting cover are extremely higher.What has been noted especially this year is the effect that land clearance and the resultant stock fencing has on a big cats ability to hunt.The recent leap in lamb and beef as well as corn prices has made farming a little more worthwhile were it not for the corresponding jump in compound,fuel and other costs and it,s had the effect of a new type of enclosure of the land.Stock fencing put up to accommodate the countys increasing number of sheep and cows,in particular wire topped sheep netting against closely trimmed hedges makes for poor cat hunting places as does the recent fad of large enclosures of deer fenced ground commonly called by it,s misnomer of rewilding.It,s a fact that Sussex is a lot less wild than it was say even 5 years ago,farms have had to make more use of the same amount of ground just to keep going and this has had the knock on effect of pushing off the Sussex big cats from ground they previously frequented.Cut down or even just reduce the width of a hedge,add a stock fence and you have removed deer habitat, greatly restricted their movements and in turn their predator the big cat will visit somewhere else.
So,to the square size of our big cats range or at least to what is known for the months of december and january the data is very thin to say the least but it,s thought it heads north to the Wealden sandstone ridge where the denser forest hides it from observation.I said in the previous post on spring movements that it,s range extends to around 140 sq.km however there was around 12 days of the month where it wasn,t being accounted for,this year however fresh info has come in which rather reaffirms what was previously thought but couldn,t be confirmed in that it did indeed range a lot further west than stated and most likely a fair bit further north east which makes it 18 kilometres north to south and 26 km east to west making this around 468 sq.km.This area has now been confirmed by exhaustive analysis of fresh info coming in this year and if we couple this with the highly likely deep winter supposed range in the far north we have a figure of 638 sq.km.This is huge,far bigger than previously thought and i must admit i,ve gone over everything so many times to check but i keep getting the same results.I realise that anyone reading this will confer and compare these results to range sizes of big cats like leopards on foreign soils who can move around in areas a quarter of this size but it must be remembered that Sussex is heavily populated with large and small towns peppering the country and fracturing suitable cat habitat.Large house building programmes have gone up on the edges of nearly every urban area reducing former farmland in Sussex by several thousand acres every year.
Although these results have not been conducted with the radio collaring that backs up results found abroad by the various big cat groups and i rue the day that this would ever happen over here,we are superbly set up in this country in having a vast amount of witness data to analyse that is completely absent from,say,Ingwe in Africa which a far lower human population.It is open to sceptism quite rightly in that no genetic analysis has taken place and that too much emphasis is on witness reports and carcase investigation and not enough on spoor but that is just the way it is.In fact this area size does concur with similar sizes that the other big cats from across Sussex would have given the number that it is thought are here(at least 12 no more than 18) and this territory size is necessary given the prey needed to keep them going throughout the year.In fact if we take a 600 odd square km block it does fit in very nicely with the other cats areas.It does all seem to fit.These results cannot though be compared to other areas of the country i think as Sussex has a peculiar range of habitat and soils that restrict or enhance big cat movements depending on the type of season but i,m sure that it,s relatively typical in the large amount of ground needed by our apex predators the big cats.....