Saturday, 21 March 2009

DON'T BOGART THAT ROACH

EDITOR'S NOTE: It wasn't actually Maxy who came up with that title. I wonder if you can guess what it actually was?

This whole new species in the pet trade thing of mine is coming along nicely. I recently received an order, to be split between CFZ HQ and myself, consisting of 5 undiscribed species of cockroach. These are not cryptids, but they are the next best things; something science has yet to find a name for. They range from being tiny dark brown animals; right up to large showy species which are pretty enough for every naturalist to admire. In this little collection of gems, we have species that are known to species level, but appear to be a new sub-species, those known to genus, and 2 are known to family only. The last two especially are special indeed.

But before we take a look at the different species, let us first look at what the hell a cockroach is. They can be grouped into a couple of “looks”, each suited for a different habitat and mode of life (NOTE: these groupings are not taxologically correct). First we have the large bodied flightless species who spend their time either underground, or under shelter of some sort. We also have the smaller long legged reduced wing species, which lead a more active existence. They tend to run from danger, not fly. The small species with full wings are the most common; indeed, the British species belong to this group. Finally, you have the large winged species. Most of these are partially arboreal, but some become so large that they can no longer fly.


Termites, mantids and cockroaches are closely related, and the name Dictyoptera has been erected to name the group. Cockroaches first evolved in the early Carboniferous period, about 359MYA. Mantids evolved from “proto-cockroaches” about 145MYA in the very early cretaceous. So, as Tyrannosaurus rex was romping around biting chunks out of Ceratopsians, early mantids were munching their way through small invertebrates on a micro level. Proto-cockroaches (or Blattoptera) are cockroach like insects that the true cockroaches first evolved from. Looking at a large cockroaches’ leg, you can see the numerous large spines projecting downwards from the leg. It is not hard to see how these could have evolved into raptorial appendages. Termites are just social wood eating cockroaches. They probably evolved about 120MYA in the Cretaceous from a similar group to Cryptocercus, a small wood eating cockroach. Genetic studies have shown that Cryptocercus shares more DNA with termites than any other genus of cockroaches. It is the only cockroach to exhibit true social behaviors like caring for it’s young. I always find it funny when I say “cockroach” to people, and get a repulsed face. Say mantis or termite to them, and they usually hold them with regard and respect in their mind. You now know that they are basically the same thing.

Cockroaches are best known for being pest insects, which some of them are. But only 25-30 species out of the 4,000 around today are pests. They are generally tough animals, able to survive for a long time without food or water. Indeed, that old myth about cockroaches being able to survive for a month without it’s head is actually true!
In cockroaches, the head performs sensory functions like sight and smell, as well as being the holder of the mouth through which the roach drinks and feeds. Like all insects, the mouth is not used as a respiratory organ, instead they breathe through a series of tubes called trachea. Outlet holes called spiracles on the side of the abdomen open into the trachea, which, like our lungs, feed oxygen to the tissues, and remove carbon dioxide. Large species, with their high oxygen requirement, need to pump their abdomen often to keep air moving through the tubes. Insects also have no brain, they instead have ganglia decentralised throughout the body. Each ganglia controls, say, one pair of legs and acts both independently and in combined movements with the other pairs. In chordates, decapitation leads to death as almost all functions are controlled by the brain. In insects, they will carry on living until starvation, desiccation or predation claim them.

Another myth is that cockroaches will survive through a nuclear war. Well, they will certainly survive better than us, but for an insect, they are nothing special. Most cockroaches have a radiation resistance 6-12 times higher than a human, but animals like flies have even higher resistances. Radiation affects cells only when they are dividing, either by mitosis or meiosis. In humans, cells divide constantly to grow our bodies, repair ourselves or to produce sex cells. In insects, cell division only occurs at ecdysis (skin shedding). Only after they have shed their skin, do the cells begin to divide to quickly grow their bodies before they harden. If a nuclear blast occurred whilst they were hardening, they would be effected. If it occurred whilst the insect was hard, there would be little effect to the insect. However, long-term radiation could hit the insects when they shed, so they are as at risk as us to long-term radiation.

Cockroaches are generally silent animals, but supposedly there is a Floridian species which makes a chirping noise. Better known is the hiss that members of the tribe Gromphadorhini make by contacting their abdomen and forcing air out of the spiracles to create a predator repelling hiss. Members of this group (particularly from the genus Gromphadorhina) are common pets for those with a taste for the unusual, and are often seen in zoos as a handalable exhibit because they are a very large insect that although very impressive looking, is actually very calm when used to being handled. Cockroaches are in fact fairly large for insects. Like mantids, the smallest members of the group are about thumbnail sized (with the average being just above this size), whilst the group contains a very high number of large insects. Some of the largest and most impressive are:

Blaberus giganteus, the giant cave cockroach. At up to 90mm long, this is one of the longest cockroaches. Males are slim and fly well, but females have such massive bodies that the best they can manage is a sort of controlled fall. Males are often aggressive to each other, and both sexes release a very pungent smell which always reminds me of a nice vaguely fruity chemical. A few nymphs of this species usually retail for a couple of quid each.
Macropanesthia rhinoceros is the largest cockroach. At 75mm long, it is not the longest, but it’s sheer bulk more than makes up for this. They can weigh about 35g, which is huge for a terrestrial arthropod. They live for over 10 years and feed on eucalyptus bark and leaves exclusively. They dig and live in deep burrows with networks all around. Males (being larger and with a shovel shaped pronotum) do most of the digging, and the young usually stay in the burrow for a year before they move off. An adult pair of this species can set you back £80!
Megaloblatta insignis is the longest cockroach. At 105mm long, it is a huge beast that has been very poorly documented in the wild. It apparently (and very oddly) mimics larger Blaberus species, but differs in a few areas obvious to a layman, chiefly amongst which, no Blaberus is the uniform brown that M. insignis is. This could be something to do with the defensive chemical I spoke about earlier, but this is just my hypothesis and not scientific fact. This species has not been raised in captivity in the west.

But enough about roaches as a whole, we need to look at the species currently in my care. We start with a species known in the trade as the African Bullet Roach. Why? Well, they are from Africa and move as fast as a bullet! They are a small species getting to between 12-17mm as adults and were first collected in about 1997/8 at the base of Mt. Kilimanjaro in Tanzania. They are so easy to keep and breed that they are being used as feeder roaches for larger amphibians and reptiles. Just run that through your head, an unidentified species, being so common and numerous, that it is thrown to toads without a second glance!


The second species is one that I have yet to photograph properly, due to their small size and fast speed! This is Blaberidae sp. “Kenya”. Notice the “dae” on the end of that name. This means that this species is only known to family level, not even genus (like the above species). Males are an appealing orange colour, but females are a dark brown with reduced wings. They are only small at 10-12mm, but I am really looking forward to breeding them.

Now we look at Pycnoscelus sp. " Malaysia”, a small parthinogenic species (where females can produce offspring without a male) related to the sort-of-pest-sort-of-not Pycnoscelus surinamensis which causes a problem with its size and speed by being able to do well in most conditions (as long as there is a lot of moisture), so it jump’s animal tanks easily. They are tiny, which adults rarely reaching 10mm.


A cracking species is Eublaberus sp. “Pantanal”. This species is related to two common roaches in the hobby, E. disanti and E. posticus, but has much more black on it’s head with paler wings. It is found in a more southerly area than the other two species, and at 50mm, it is longer than the other two species. It is a stunning critter and both nymphs and adults are very showy whilst being rather shy and tending to burrow.



Finally, we have a new colour form of Eurycotis opaca, a large species up to 50mm long. It is related to pest species, but is itself not a pest. It has the build of a running species, but it is much larger than most. Adult’s have a blaze of colour on the pronotum which looks to me vaguely like a setting sun.

I have tried to contact a chap called Darren Mann, an expert in cockroaches, to see if he can identify whether it is worth naming them ourselves, or if they turn out to be a colour form of described species. He is out of office until early April, but naturally, I will keep you updated on developments.
We are also working on a project to try and document the behaviour and biology of these animals involving volunteers from the CFZ readershi[, so watch this space.

Friday, 20 March 2009

Back-dating the Somerset Cat.

On Monday, I went on a field trip. Field trips in Geology are a common occurrence; what better way to learn about rocks than to get out there and look? We were off to a place called Vallis Vale in East Somerset, the site of an unconformity. An unconformity occurs when sediments are laid down, folded so the beds lie at an angle, and then eroded.
Younger sediments form on top of the old sediment in typical straight beds, and an unconformity is created. They are only visible when falling sea levels and colliding continents cause the unconformity to rise above “normal” ground level.
Cutting by a river or quarrying also helps. You can see in the photo the different dips of the beds. The beds themselves can be dated by looking at the fossils within them; the rock below is from the Carboniferous period, and the rock above is from the Jurassic. This site is geologically important as it was described in the world's first Geological Survey memoir in 1846 and helped establish the science. Anyway...


In the minibus on the way up, through the sounds of Rush’s “2112”, I overheard my teacher talking to the lad sat in the front seat that he had seen a “black panther” crossing this road at night. I realised where we were, and found that we were about 800m from the field in which the big cat has been killing dozens of sheep! Hooray!

The next day I stayed behind to ask him about it. He said he had been driving along the road at about 2145 to take his son’s babysitter home, when out of a wood on the left this Labrador walked out onto the road. He stopped to see if it was ok (clearly a dog walking around on its own is a cause for concern), but it suddenly dawned on him that it was a big cat. He stopped the car and watched the cat watch him. It carried on it’s way to the right, and he can remember clearly pressing the button to wind the window up; just in case.

He also said that his first encounter of big cats (or rather, something) happened at around the same time when climbing in Cheddar Gorge. He was getting up to the top of the ridge in an area where no people go because it is very heavily wooded. He got to the top of the ridge, and found an area of scraped ground with a large mound of foul smelling dung deposited inside. He didn’t recognise it as being something he was familiar, but he left it due to the difficulties in getting it back down again.

My teacher is not unknowledgable when it comes to animals; parts of teaching geology necessitate a good knowledge of the natural world, and I would take his account as highly credible. The diagnostic features he remembers are; very long thin tail, jet black colour (“such that if it was hidden in bracken or a ditch, you could come within 3ft of it and not notice it was there” he said), slightly pointed ears and a very calm demeanour. It’s total length was about 2m long.

This is all very interesting, but there was one more thing. The sighting happened 14 years ago.

Friday, 13 March 2009

COMPETITION: Walking in a winter wonderland

Back in early February, as I am sure you remember, the British Isles had a flurry of snow. Here in Somerset, we had our fair share, and I - being the good field-man I am - went up to the usual place to see if Mr. Kitty had left any traces of his existence. The farmer had moved his sheep away into shelter over the cold snap, so I knew that there would be no new kills to poke.

I battled my way up to the field, parked up, got out and had a look around. I was extremely surprised to see the amount of snow prints I did (nothing feline though), and got round to the fun business of identifying them all, as all good naturalists should. Now, I know what most of these are, but the real question is, do you, the CFZ blog readers, have any idea what these prints are from? The person who sends in the most accurate answers as to what the following 8 photos show wins a year’s subscription to either The Amateur Naturalist or Animals & Men magazine, it’s your choice! Answers can be sent to max@cfz.org.uk. The number at the end of the text next to the photo shows the question number.

First up, we have this image. Any ideas? They are right down to the ground (3”), so we must be dealing with something with fairly small feet for its body size.
The two prints are about 6” apart, and each print is 1.5” wide. Claws are clearly visible, which are short but thick.
The central pad is also diagnostic. [1]



Ok, now try this. We have two prints, which plunge very deep into the snow with a pretty large amount of kicked back snow. The prints are about 1-1.5” in diameter, and are about 1’ apart. What do you think they are? [2]






Moving briefly to a photo I took near my house, what have we here?
We have thinner snow, maybe an inch, with two sets of prints.
One very large long one and two smaller distinct prints. The prints are about 2” wide.
Any ideas? [3]


And this one? An odd one this. The snow is very thin here. [4]






And this? Four points originating from a central source. [5]













Right, let’s get tough. The next few photos are fairly indistinct, and I won’t be adding my suggestions and hints for any of these. Good luck!



Oh, and just for fun, this is the amount of prints that you get around a decaying carcass as scavengers, errr, scavenge for meat left on the bones.


Thursday, 12 March 2009

Walking in a Winter Wonderland: the answers.

Well, hopefully you enjoyed the little quiz that I put up a few days ago. I am pleased to announce that Sean South won the competition, by getting six out of eight completely correct.

The answers, and the precise details as to what gives them away, are below.

1. A red fox. The characteristics you should have picked up on were the visible, blunt claws with 4 digits, which show it to be a canid, plus the size of the print and particular spread of digits from the central pad, showing it to be a fox. A dog in comparison would have it’s digits spread less than this fox.

2. A roe deer. The speed of the movement (snow kickback) and size (stride length) show the animal to be large, and the thin prints going deep in the snow show it to have narrow feet. Must be a deer! I know it was a roe deer because I saw them making the tracks, but the distance between the strides show it can’t have been a large deer like a fallow.

3. A domestic dog. The four digits with visible blunt claws show it to be a canid, but the size and the narrower spread of digits show it to be a dog.

4. Two dog prints on top of each other. The 6 digits give this away a bit! Again, the claws were visible.

5. Probably a blackbird, but I am not an authority on bird prints, so any medium size passerine would have been acceptable. The flat feet show it to be a passerine.

6. Probably a fox digging. The print in the centre of the depression is from a fox, so I expect that the rest of the print was made by a fox.

7. A rabbit, I think! 4 main depressions are visible, and it must have hit the ground with some force to have punched straight through to the ground. The close together prints show that this is probably a rabbit.

8. Not a clue! It looks to have been melted by the sun to for a print larger than the original. This was probably a fox.

Needless to say, the last few prints are up for interpretation, and my ideas are just informed guesses. I have printed below the suggestions some people made as to the last 3, make up your own mind who is right!

badger
hare
okapi
chupacabra

Methinks that I know the young lady who suggested `okapi`, and that someone else wasn't taking this excercise particularly seriously...

Walking in a Winter Wonderland

Back in early February, as I am sure you remember, the British Isles had a flurry of snow. Here in Somerset, we had our fair share, and I - being the good field-man I am - went up to the usual place to see if Mr. Kitty had left any traces of his existence. The farmer had moved his sheep away into shelter over the cold snap, so I knew that there would be no new kills to poke.


I battled my way up to the field, parked up, got out and had a look around. I was extremely surprised to see the amount of snow prints I did (nothing feline though), and got round to the fun business of identifying them all, as all good naturalists should. Now, I know what most of these are, but the real question is, do you, the CFZ blog readers, have any idea what these prints are from? The person who sends in the most accurate answers as to what the following 8 photos show wins a year’s subscription to either The Amateur Naturalist or Animals & Men magazine, it’s your choice! Answers can be sent to max@cfz.org.uk. The number at the end of the text next to the photo shows the question number.


First up, we have this image. Any ideas? They are right down to the ground (3”), so we must be dealing with something with fairly small feet for its body size.


The two prints are about 6” apart, and each print is 1.5” wide. Claws are clearly visible, which are short but thick. The central pad is also diagnostic. [1]






Ok, now try this. We have two prints, which plunge very deep into the snow with a pretty large amount of kicked back snow. The prints are about 1-1.5” in diameter, and are about 1’ apart. [2]


Moving briefly to a photo I took near my house, what have we here? We have thinner snow, maybe an inch, with two sets of prints. One very large long one and two smaller distinct prints. The prints are about 2” wide. Any ideas? long one and two smaller distinct prints. The prints are about 2” wide. Any ideas?







Moving briefly to a photo I took near my house, what have we here? We have thinner snow, maybe an inch, with two sets of prints. One very
































[3]

































And this one? An odd one this. The snow is very thin here. [4]































And this? Four points originating from a central source. [5]


































Right, let’s get tough. The next few photos are fairly indistinct, and I won’t be adding my suggestions and hints for any of these. Good luck!































[6]



















[7]




















[8]

















Oh, and just for fun, this is the amount of prints that you get around a decaying carcass as scavengers, errr, scavenge for meat left on the bones.




















Wednesday, 11 March 2009

An opossum's tail

Opossums are a group of about 90 different species occurring only in the western hemisphere, occurring from southern South America right up to Canada. The most famous species is Didelphis virginiana, the Virginia opossum. It looks vaguely like, and is usually portrayed as being, a giant rat with a fluffy coat, when actually it is a marsupial that happens to benefit from human habitation as it uses houses for shelter and food (scavenging for scraps) in the same way that rats do. I guess it’s partly hairless tail doesn’t help its cause...

Possums are a group of about 65 different species occurring in Australia, Sulawesi and New Guinea. The most commonly encountered species is Trichosurus vulpecula, the common brush-tailed possum. At a maximum of 4.5kg, it is not far off the above species in size, but it’s bushy tail, shorter muzzle and darker colouration make it easy to tell apart. It too likes people’s houses for the same reasons, and usually it causes an annoyance for people who have to sleep with them running over the roof every night.
Now, although there is only one letter different between “possum” and “opossum”, apparently this causes a problem for some people. Google for instance, throes up dozens of photos of both possums and opossums when you google “possums”, mainly of D. virginiana. Why on earth does this species have the common name of “possum”, when it is nothing of the sort?

Unlike other common name confusions, which are usually due to visual similarities between species, D. virginiana looks very little like a, for instance, T. vulpecula. It must then be pure and simple laziness which causes people to mix the two names up. Why bother to say “opossum” when you can say the easier “possum”? Waste of time innit? Whose gonna care ‘bout one letta?

Hummm.

The catalyst for this short rant is a video (http://www.weebls-stuff.com/toons/Australia/). Although very funny, and the vocals say “possum”, they cock it up by depicting a very rat-like D. virginiana with the long muzzle and nearly hairless tail. Oddly enough, the idea that possum attacks are the “number one reason for a day off” is, according to an Australian friend, complete rubbish, mainly because they only attack people in extreme circumstances. But how hard would it have been to google “possum”, looked in Wikipedia or whatever site first comes up, and found a representative possum from Australia?
Again, why bother? What’s Joe Public going to care? Well, if I had my way, they damn well would. I bet even 8yr old me could have told you the difference between possums and opossums. Why not everyone else?


Saturday, 7 March 2009

A picture's worth a thousand cryptids (OK that headline is completely meaningless but Jon thought it up, and I have to humour the old chap)

For this evening/morning/whenever you read this you are going to be talked at by me about the importance of photography and being a naturalist.



Digital photography is quickly becoming a very mainstream pastime. No longer do you need to faff about with darkrooms and expensive films; a simple household computer is all you need. The advantage of the technological revolution is that equipment drops rapidly in price over time (just look at widescreen televisions; you can pick up a 32” LCD TV for £500, a couple of years ago they were over double that!) whilst the quality of the goods increases (you can look at digital cameras this time). So, we are getting double benefits: prices for goods are dropping as the goods get better and better. It’s a great situation to be in, and with the current recession reducing demand for luxury goods (cars, for instance, have seen an unprecedented 35% drop in demand this year compared like for like to last year), if you can afford to buy a good digital camera, now is the time to do it!

In this series of blogs (yes I know, I should be following a trail of dead sheep, but the famer has moved them indoors for a while, so the cat has buggered of elsewhere), I will be looking at what to look for in a digital camera, if you are a naturalist. I could talk at great length about D-SLRs (digital single lens reflexes), but for the moment I am going to discuss more affordable options: entry level cameras.


In the above photo, the black dots are starlings.

A basic camera will set you back about £100 (roughly) and will probably have a 3x optical zoom, still and video modes, about 8.0 megapixels, a macro mode and a fairly large screen. A 3x zoom is not exactly superb, but all the other features are essential for a naturalist. Still and video modes gives you flexibility when shooting without needing two separate cameras, 8.0 megapixels allows you to produce a fairly large image which can be printed out at a later date up to about an A4 size, the large screen allows you to clearly focus on your subject, whilst the macro mode allows you to take clear photos of small flowers/invertebrates. These cameras are usually pocket sized, and are very easy to carry around in a pocket or handbag, and are aimed squarely at beginners, or people who don’t want to fuss around with photography.


Most of the settings are automatic, and there is usually a small manual override on some settings, but usually very little. A large memory card is essential to make sure that you have enough space for images, no matter what happens. So, if you do see that elusive big cat you have been chasing for ages, you want to be able to keep taking photographs for the full duration that you can see the animal and not have to worry that you are going to run out of space on the memory card, which will prevent you from taking any more photos. You don’t need expensive aftermarket image enhancer programs either. Windows XP/Vista (and I assume its equivalents) comes with a “fix” tab in the image viewing screen. It is not fancy, but if you are shooting at night you can enhance the brightness to pick out any figures in the gloom. You can crop the image in the same way.



Cropping cuts out a piece of the image to allow you to take out areas outside of the subject to enhance the look of the image. You can also use it to show a particular far away object in a better zoom, letting you, as I said earlier, determine between a bustard and a goose.

If your budget will stretch to it, a camera with a better optical zoom is a good investment for obvious reasons (to look at Jon’s article the other day, a bigger zoom allows you to see if it was a bustard or a goose when you look at the photo afterwards). Some manufacturers will con you by telling you the digital zoom. This is something quite different to optical zoom (where lenses move inside the camera to zoom), where the camera zooms in digitally on the image. It gives the impression of a bigger zoom, but when you look at the photo on the computer, it will probably be very grainy. You could get exactly the same results by cropping the image from your computer.

Beware however, as you move up from the beginner’s pocket sized cameras, the need to incorporate more space for lenses to move necessitates the need for a larger lens, so the size of the camera tends to increase from this point onwards. But, these more expensive cameras come with customisable features, allowing you to fiddle manually with things like ISO, exposure settings and white balance to produce more tailored images. Image stabilisation (helpful for shooting fast moving objects, or when you are moving) is also a very handy thing to have.

But why am I taking the time to talk to you about photography in a zoological blog? It is because I have a dream.

A dream of a day when everyone, interested in zoology or not, takes a camera with them everywhere they go. How many more photos of cryptids would there be if everyone took a camera around with them? The quality of cameras is rising rapidly, and their use to naturalists is increasing. I find myself wanting to kick people after I talk to big cat witnesses when I realise that although the big cat is a regular in their area/field they never thought to bring a camera with them. A not insubstantial amount of big cat sightings are made face to face with the cat as both sides stare at each other in surprise. Meetings like this can go on for minutes on end, think of how many photos you could take in this time! Even if the first photo wasn’t brilliant, you would still have lots of time to tweak the settings for a better next shot. Why on earth don’t people do this! One of the best ways to prove something’s existence is to photograph it; for the price of one piece of hardware. A small price to pay methinks.

Plus of course, cameras are kinda nice for photographing the kids growing up, family events or holidays. Talk about killing two birds with one stone...