If you are a regular here, you'll know that I'm writing a range of occasional series - 'what's in a gall', 'wildlife-friendly gardening' and so on. One of these is the diary of the pond at Highbridge Farm (Hampshire, southern England) - for pictures of the pond itself, see the
April diary entry.
Events have moved on - from a summery spring to an autumnal summer, and the combination of rain and warmth has produced a lot of plant growth, plus of course the change of species with the seasons and the development of a seeded meadow around one side of the pond. It's also important to remember that this is a 'working' pond i.e. it is used for small-scale irrigation. So, what has changed recently?
Well, as expected there are more dragonflies and damselflies (Odonata) such as the blue-tailed damselfly (
Ischnura elegans) below with its bright blue 'tail-light' - plus some large nymphs which must be close to emergence. Fingers crossed for some good photos of these, including some exuviae (shed skins).
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhX4r1xbbCiXDL1SOYBYJr61cyAKL0asTS8SqsZN1eXbLn9G7VWpdF3-DSRid7va-2EdMd2HpcujobtA6Ss5gOtLoNA2SojuA2KC6xo-I9-6yo9h5ZSrY7OrV1m4VMNERB7mTB3QNwVvLFC/s400/bluetdam1a.JPG) |
Blue-tailed damselfly Ischnura elegans |
Within the water itself, a number of molluscs have appeared, including the impressive (by British standards) Great Pond Snail
Lymnaea stagnalis - this one is around 4cm long...
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiDwKb0rTqEq5rKH5asga_NwTtq5AC3e-d0kgu4n9E663wbim6QuKqdnYBYUnQqonhO4Y5RLXxnXH_Fs-PLSQ_xraUpf4YY9F8QDsQdfhjTsXMnwsCH-wtwRpxqN2tTKNX7Octg4aFNd1fZ/s400/lymnaeastagnalis1a.JPG) |
Lymnaea stagnalis feeding on algae and plant material. |
Personally, I hope the mollusc community develops a taste for the algae in the pond - with warm temperatures comes blanketing algal growth; last year this was removed by hand (aided by rakes, grapples and a small boat) and I suspect this will need to be again soon. A small amount is not a problem - in fact many invertebrates seem to use it as an important moist substrate - but for the development of aquatic plants, light penetration is required which the algal can block out. Back to the aquatic molluscs - I did notice that they have an important role in the terrestrial food chain; where stranded on land, they appear to form a source of small-scale carrion, used by invertebrates that like that sort of thing...
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj1ylBYog2nIKC7QGsIT4YzjexvrQndGIC2hEkTZqoEjhb8_6co4TYr645NVIx3bqB-uYliCXJmxpE-LtiFSQVkMYr1BCjO4E5DbHYuzQx7e5WK3X3wtD197f_BIDKhXoL80uvCX1XnOa2F/s400/fly%2526snail1a.JPG) |
A fly (with the silvery jowls, I think it's the common Greenbottle Lucilia caesar) guarding a dead water-snail. It almost appears to be challenging me to try and take the snail, and certainly didn't want to abandon its prize. |
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Once I was no longer considered a threat, the fly resumed its business - presumably feeding as I saw no evidence of egg-laying behaviour. |
Staying at the pond edge, the marginal vegetation (reeds etc) is gradually developing and the structure is clearly important with a range of invertebrates using it in different ways - hunting, mating, egg-laying, pupation and emergence, feeding and so on.
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhxCT9OxUVLSrF0S8Am8Om1b-Jktpg-OwFPk7JZ0Hv1nH098rQMPty8_vvSiYBScYurAcVsrEEpz45Ept-o2DuLGiU72XTRO1Js6OKkw3K6zMIOo3LaXWmyaqakN0a0bj8UfA5zEw_0Iozq/s400/2spot1a.JPG) |
A pair of 2-spot ladybirds Adalia bipunctata busily making more ladybirds on the head of a reedmace plant - important given the threat posed by the invasive Harlequin ladybird Harmonia axyridis. |
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Following the ladybirds' example (no, I'm not obsessed, honest - they just don't move much when mating, and so are easier to photograph), a pair of Donacia reed beetles. |
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgEBS7Ri_76IoUh3YcPOasJlFz99MqCAOvNzWA4huXfqwmFyY69W5OsYp6N2TvT3aGQKe7baqO8-ypUAh-7BMRAIZeGHS6thdh61W29lPfkoL82Tmkqo4EZ3bcX1oPJPOgHrQ2JOEzN9hkf/s400/textensa3a.JPG) |
Moving onto spiders, ventral view of a female Tetragnatha extensa - note the large divergent jaws. |
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhafNP56TeNrhjayq7A6E9EtbDZ1XbSMhVbG6eH8nBU-z2NooMz-AcEF1kDlHyaUN_VEBTpNFfqwMHXaPErCIfxznjZRCn7tbuPcDSUiOkEflg30bSyt5TEszCAl9Kt7lMirrxgCHQaYL5A/s400/textensa3b.JPG) |
Cautiously approaching (remember the female's jaws), a male T. extensa - as well as his own large jaws, he has two swollen palps at the front - modified structures used for sperm transfer. Onward brave spider! |
I'll be following the development of the pond and its inhabitants - after all, many ponds have been lost from the British landscape and they are of key importance for nature conservation - for example, see
Pond Conservation, the
British Dragonfly Society,
Froglife and the
Freshwater Biological Association. More soon!
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