The Purple Ponds of Lithines

The purple ponds are teeming with microscopic life. 

We'll make our way back to the main Sitia-Makry Gialos road to Lithines where there are a few interesting ponds to the north west of the village that are worthy of investigation not least of all for their intriguing colour at this time of year. We are still awaiting significant rainfall and the ponds are very shallow at the moment but packed full of nutrients and it is these that are responsible for their unusual colour. If you check them out under the microscope they are absolutely teeming with microscopic life with nematodes, desmids and the like flitting about at tremendous speeds all over the place. But before we get down to them lets see what we can find on the way.

The first signs of the upcoming change of season are here by the track with these Wood Sorrels or Bermuda Buttercups which will soon be adorning every roadside and olive grove. You can make a nice warming winter soup with these; just bring a pot of chicken or vegetable broth up to the boil, chuck in a handful of cooked rice and a handful of wood sorrel leaves, simmer for about eight minutes. Finally stir in a dollop of cream, salt and pepper to taste and serve with a couple of the flowers floating on the top. (Obligatory word of caution: Wood sorrel contains oxalic acid so if you suffer from rheumatism, arthritis, gout, kidney stones or hyperacidity then it may aggravate the complaint but for the rest of us the odd bowl or two is fine). You can also add flowers or leaves to salads for a sharp, lemony bite if you wish as well. As with all wild plants, wash them well, remove any bugs such as this Shield Bug nymph and pick away from roadsides or other contaminated areas.

There are the ponds down there which we have to find our way down to somehow but first a Small Copper has just landed nearby. They like to lay their eggs on Sorrel which is their caterpillar's food plant and you could be forgiven for thinking that this is rather handy as we have some wood sorrel nearby but not so. This is the old confusion of common names. The Wood Sorrel is Oxalis pes-carpe in the family Oxalidaceae; Sorrels (without the wood) are plants of the Rumex genus in the Polygonaceae family. The ambiguity arises because they are all acidic tasting and the word Sorrel reflects this being derived from the old French 'sorele' meaning sour.

Here we are, down at the ponds without too much difficulty and there doesn't seem to be too much activity on the surface but just take a look at this rainwater ditch nearby where the water is a little more free draining. The dragonflies are having a high old time, there must be six pairs here at least, flying along in tandem with the males clasping the females' necks with their special pincers. These little Darters stay together after copulation and then the female gently dips her abdomen into the water and lays an egg which, if we sit and watch them for a few moments we can witness. There she goes, and another, and another. These will hatch out into extremely predatory nymphs and providing that the ditch doesn't dry up they can spend up to three years in this stage before emerging as adults.

And finally the ponds themselves and what an unusual, attractive colour they are at this time of day. Not entirely devoid of life on the surface, I can see one small, white insect skating along on the surface but what precisely it is I cannot tell. No, I am not going to wade in and take a closer look. I have a strong suspicion that beneath this shallow water there lurks a good few inches or more of evil smelling sludge with which I have no desire to get better acquainted thank you. Well, that just about wraps it up for Autumn. Tomorrow is the Winter Solstice and if you'd care to join me in raising a glass to the shortest day of the year the the time of the solstice, when the Earth is at its furthest point from the sun, is 16.48 Universal Time or almost ten to five Greenwich Mean Time as us oldies prefer to call it. That's a most convivial time for a libation out here in Crete being about ten to seven in the evening. So, wherever you are and whatever you're celebrating, have a good one and we'll meet up again on January 3^rd 2018. Cheers!

Photographic Bit

Many of you have asked me what photographic equipment I use so for details of aperture settings, shutter speeds etc. my pictures will be on Flickr within a few days and that has all the geeky stuff. Pictures were edited with FastStone Image Viewer and combined with Microsoft Paint.

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LINKS:

Share your nature thoughts, photos and comments on Naturalists (the facebook page that accompanies this blog)

Explore the region with the #CreteNature interactive Hiking and Nature Map

Cretan Flora

Flowers of Crete;

BIRDS OF CRETE

Crete Birding

Greek Butterflies and Moths

Aquaworld Aquarium

Visit Greece (National Government Tourist Office)

The Dew Ponds of Katharo

We’re taking a break from our trek up the Eden valley this week as I want to take you up to the Katharo Plateau in the Dhikti mountains. Yes, I know we’ve been there before (Cathartic Katharo) but I need your help to examine some summer ponds.

Cirl Bunting, Emberiza cirlus at one of the dew ponds

Here we are, all dressed up in muted colours for the occasion, and our first job is to lie very quietly in the mud and see what’s happening. These ponds retain water all through the long, dry summer and I believe that they work on the same principle as the Hampshire dew ponds that the eighteenth century English naturalist Gilbert White described in his book, The Natural History and Antiquities of Selborne. That is “more than double the quantity of dew falls on a surface of water than there does on an equal surface of [moist] earth”. The clayey soil in which we’re lying prevents the water from seeping through the limestone rocks. As you can see it’s a great place for dragonflies and we have birds popping in for a drink. There’s a Cirl Bunting, look. Many buntings have declined in North West Europe due to a lack of weed seeds and insects but they’re obviously alive and well here on Katharo where traditional farming practices are still employed and herbicides and pesticides are not.

Water Strider, Damselfly larva, Water Scavenger Beetle

Let’s take a look under the water and see what’s lurking there. What do you mean you didn’t bring your bog snorkelling gear? Ok, you sit and watch the Water Striders skimming about the surface and I’ll go down and interview the wildlife. A small Water Scavenger Beetle, though that is a bit of a misnomer as they can be just as predatory as the Predacious Water Beetles. You can tell them apart by the way they swim: these move their hind legs alternately but the Predacious Water Beetles kick theirs out together – sort of doggy paddle versus the breast stroke. We also have a Damselfly larva. These larvae are also known as naiads or nymphs after the female spirits that dwelt in wells and streams in Greek mythology. You can tell that it’s a damselfly and not a dragonfly by those three tail filaments containing the gills through which they breathe. Dragonflies don’t have these and breathe through their rectums (which is not something you should try at home).

Apart from each other I wonder what else these little creatures are eating? For the omnivores and vegetarians down there we have plenty of this stuff. It’s called Chara and though it looks very much like a plant, it isn’t. It’s a green alga and, as such, is more closely related to green seaweed than flowers. The little red buds that you can see contain reproductive spores and, as you can tell by the amount of Chara in the pond, they are remarkably efficient. This is just the top level of the ecosystem that we can see with the naked eye; there’s far more going on that we can’t see so grab a pipette out of my bag there and we’ll put a drop of water under the microscope.

Desmids and Diatoms

Ah now, these top two, Closterium and Euastrum are desmids which are green algae, the same as the Chara but they are unicellular. The Euastrum looks as if it has two cells but they are in fact symmetrical compartments of the same cell separated by a narrow bridge. The bottom two, Epithemia and Rhopalodia are diatoms which are more closely related to the red algae. Forensic scientists love these things because if they find them in a murder victim it shows that they were drowned rather than killed and then dumped in the water. If they can correlate the species mix in the corpse with the species mix in a certain pond for instance they can even tell where the person was drowned. Gruesome perhaps but just one of the obscure ways that a knowledge of nature impacts upon our lives.

The Naturalists' Taverna, Katharo

What a fascinating little pond; water, water everywhere but not a drop to drink. I think that we’d better rectify that and a visit to Yanni’s taverna is a must when visiting Katharo. Yanni is a naturalist himself and you can spend a pleasant hour or two reading the walls of his taverna over a convivial libation. There are pictures and descriptions of birds; books and posters of flowers (provided by our friend Steve Lenton at Cretan Flora) and a section on the fossil mammals of Crete, some of which Yanni himself discovered. It’s surely the best naturalists’ taverna on Crete. Who’s round is it?

News Update

Remember that little diatom called Rhopalodia that we found? It turned out to be Rhopalodia gibba, a species never before recorded on Crete. As such it has now been documented on the world wide Algae Base. Better not drown anybody in that pond then.

I see that my email address is at the bottom so feel to drop me a line, contact me on twitter @cretenaturalist

or via

Naturalists (the facebook page that accompanies this blog)

See you next week.

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LINKS:

Cretan Flora

Flowers of Crete;

BIRDS OF CRETE

Crete Birding

Greek Butterflies and Moths

Aquaworld Aquarium

Visit Greece (National Government Tourist Office)