Tuesday, 30 December 2014

Wildlife, Weeds and Who's Who in the Undergrowth

White Mustard

It’s hard to believe that I’ve been writing this whimsical diary of the Cretan countryside for a year: taking you with me as I wander up hills, delve into caves, venture beneath the waves and generally poke my nose under logs and stones to the chagrin of the animals dwelling beneath. It’s even more surprising that so many of you from all around the world continue to traipse around with me every week. Thank you. So get your boots on once again, grab your sweep nets and we’ll go and explore the weed strewn hillside for the last time this year and see what we can find on this fine, sunny morning.

This looks like a fertile hunting ground. Untouched by man since some new olive trees were planted here a year or so ago we’ve got plenty of grasses; mallow and crown daisy in leaf and a large patch of white mustard in flower. There are a lot of similar looking plants in the mustard (or cabbage) family, all having four yellow petals, and two of the key things to look at in detail are the beak-like fruits (called siliquae) and the hairs (or lack of them) on the leaves and stem.  Armed with this information and a good field guide you soon get adept at recognizing them.

(Coleopterans) Beetles
The beetles are back in numbers I see, and at all stages of development. Beetles undergo complete metamorphosis, that is, they start life as an egg, hatch out as nymphs and then pupate (like these ladybirds are doing) before emerging as adults in their many and varied forms. Some are big and showy (like this furry flower chafer) and some are really tiny like this little fellow I’ve just caught in my sweep net. Judging by his diminutive size and those clubbed antennae it could be a skin beetle (aka leather, carpet, larder beetle etc. as their larvae eat a number of man made products and can be quite a pest). The adults however tend to go for pollen which explains what he’s doing up here among the flowers.

(Hemipterans) Bugs
OK, your turn. There are two things to remember when wielding a sweep net. One, make long, low sweeps back and forth, just brushing the tops of the plants. Two, when you look into the bag make sure you don’t poke someone’s eye out with the other end. No, I’m fine, I ducked just in time. Oh, and a third thing: carry it with confidence. A middle-age person carrying a butterfly net may look eccentric but a middle-aged person trying to pretend that they’re not carrying a butterfly net looks a right plonker. Let’s see what you’ve caught. Aha, bugs by the bucket load, marvellous. This begs the question: what exactly is the difference between a bug and a beetle? Aside from the fact that ‘bug’, particularly in American English, is used to refer to any insect, scientifically bugs and beetles form two different orders (Hemiptera and Coleoptera).  As about half the insects that you come across in the field are either one or the other, differentiating between the two is a useful trick. Flight and bite is a good way to remember which is which. Beetles have hard, wing cases (elytra) which lift apart allowing the wings beneath to unfold and rather roundish faces with a pair of jaws (mandibles) used for chewing. Bugs have softer, more membranous wings (particularly at the ends) and often rather narrow faces always ending in a tube (proboscis) used for sucking up liquids. These then are all bugs: pointy at one end and soft at the other.

Orthopterans (Crickets and Grasshoppers)
While we’re on the subject of insect orders, I’ve rounded up a couple of other closely related fellows: a cricket and a grasshopper. These form the order Orthoptera and are easily recognized by their long, muscular legs adapted for jumping. Females of both types have an egg laying tube (ovipositor) at the back but only crickets have a pair of sensory organs (cerci) protruding from their rear ends. So, the chap on the left is a cricket, the chap on the right a grasshopper.  On the whole crickets tend to look somewhat flatter as well as they hold their wings against their bodies whereas grasshoppers hold their wings up more, like the roof of a house.

Gastropods (Snails and Slugs)
Let’s lay down in the grass a little and prod about in the roots. And here we find some lovely little slugs and snails (which tells me that this grass is probably a bit damp). Whereas beetles, crickets and the others fall into the class ‘insects’ (having six legs) within the phylum ‘Arthropods’ (animals with their skeletons on the outside), slugs and snails are in a class of animals called gastropods along with the occupants of the sea shells you find washed up on the beach. The thing they all have in common is a broad, tapered foot on which they glide about. They are part of the phylum ‘Molluscs’ or ‘Mollusks’ in American English. (languages evolve like species: if you separate them by a continent they have a habit of going their separate ways). This phylum contains all the soft bodied animals without a backbone which includes most of the items on the seafood menu such as clams, oysters, squid and octopus. 

Yellow-legged Gull
All of which reminds me – it’s nearly time for lunch. The weather seems to be closing in a bit too. Just look at that shaft of sunlight bursting out from the clouds over the sea. You can almost envisage angels descending from heaven. 
Well, maybe not angels but there are plenty of Yellow-legged Gulls flying about. They usually form an overwintering colony on the smooth rocks to the east of Livadi Beach so I must pop down there later on in the week to see how they’re doing this year.  Until next week then, when a whole new glorious twelvemonth awaits us – happy hunting and Happy New Year.

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