Wildlife Gardening in July and August
N.B. If your new to David’s monthly column then please be sure to read the ‘setting-the-scene’ opening piece first.
As the soils have dried out, so the summer butterflies have hatched into the sunshine. Sadly the spring-emerging species are having a really bad time but our high summer treasures are around in good numbers.
Only occasional red admirals, peacocks and commas can be encountered but silver-washed fritillaries, white admirals and a variety of browns are in good numbers in our Summer Meadow. Now admittedly the first two butterflies are migrants from the adjacent ancient woodland, but the ringlets, gatekeepers and meadow browns are our own colonies. Marbled white and skipper butterflies, also hatching from the meadow, are in lower numbers than usual but at least they are extant and with good weather can build numbers for future years.
It is quite unsettling to see buddleias in flower and not being fussed over by clouds of red admirals, peacocks, tortoiseshells and their allies.
With such a small meadow it is only too easy to loose species. On a recent exploration of a Butterfly Conservation reserve, near Winchester, there were high numbers of burnet moths but own garden population has been lost. Naturally we are hopeful that the garden will be re-colonised but, being an isolated area, that could take quite some time. With wildlife sites being so fragmented the chance of extinctions of populations is high and repopulation slow. However with more people establishing, even small, garden meadows the chances of local extinctions decreases considerably.
Search out your own local butterflies.
This is around the best time of the summer to investigate butterflies and day-flying moths. Populations are near their peak and rarer species are on the wing.
Try some less usual habitat. For example, if you live in a chalky landscape visit a heathland or oak forest and you’ll hopefully encounter some new species.
Our main lawn has again become a patchwork of mini-meadows. We do not uniformly mow the grass but leave sections uncut until they become rather straggly. The hidden grassland species take full advantage of this lull and rush into bloom. Currently we have creeping buttercup, clover, self-heal and birds foot trefoil generating colour, nectar and pollen. The food supplies attract the insects and their predators.
One common bird, that seems wary yet finds the lawn ants irresistible, is the green woodpecker. It spends much of the day moving from one small ant colony to the next. However the rooks are currently avoiding the garden. They were around in numbers in spring but can, presumably, locate sufficient supplies elsewhere now. They will again find us the centre of attention once the walnut crop is ripe for picking when they will arrive in force to pluck the nuts to export elsewhere to consume.
The Flower Borders act as green routeways for birds throughout the year but the youngsters are currently learning the ropes, and small parties of tits traverse the hedges making contact calls much of the time. In fact whilst few local birds are being territorial birdcalls still punctuate the air, with the soporific cooing of the wood pigeons being most pleasing.
Beetles are highly visible in the garden now and devoting just one garden wander searching for species is worthwhile. Many types of beetles are toxic and so can afford to be highly visible, not actively fearing being consumed. The more wary can be found by employing a simple pit-fall trap, left overnight you can anticipate at least some active specimens to identify in the morning.
The Summer Meadow now is wonderful. Chirping and flying insects abound and it is florally diverse. Nothing to do now except sit back and enjoy it!
Make your own pit-fall trap.
Dig a hole just big enough for jam jar or tin can. You could decide to place some bait in the bottom of the trap, such as meat or jam. But catches still occur with no food attractant. If rain is anticipated a rustic cover is needed. Bumbling insects should tumble into the trap.
The Garden Pond
Now that the water temperature has increased evaporation and transpiration via the plants’ leaves has increased. This decrease in water level is my trigger for a summer clear out of excess aquatic vegetation.
My own pond is dominated by an alga, Chara, which looks very filmy and has the largest cell volume of any organism I know. Chara cells look great under a microscope and one can even see the internal organelles and cytoplasm flowing around the centimetre long cells. Alongside the alga are various other plants such as Canadian pondweed, water mint and float grass. I remove a fair percentage of this vegetation, with a garden rake, into buckets or bowls and then gently wash it off with a hosepipe. Newtpoles, various pond snails, dragon and damselfly nymphs are most commonly encountered and gently returned to the pool before it is topped up.
With open water again the adult dragonflies return to patrol the area and, later, to carefully deposit their eggs onto submerged vegetation.
Collect a small quantity of pond, or slow-flowing river, vegetation and leave it in a small glass or plastic tank with natural side light. If you are lucky, and most times I have been successful, you’ll find that threadlike green or brown animals called hydra will be visible on the lighted tank side within a couple of days. Hydras (relatives of corals, sea anemones and jellyfish) have eight miniscule and threadlike ‘arms’ attached to their sac-like body. These tentacles are covered in stinging cells. When triggered by a water organism brushing against the arm, the stinging cells erupt to ensnare and kill the prey species. The prey is then engulfed. All this feeding activity can be seen by an observant watcher. Indeed their locomotion, by turning head-over-heels, can also be watched.
Overall hydra can reach 5 cm in total length, some containing mutualistic (symbiotic) green algal cells and so turn green in colour.
I have maintained hydra colonies, in the past, for years. They reproduce asexually by budding offshoots, which later detach, and sexually with egg and sperm.
You can set up your own ‘predator – prey’ population experiments by adding small numbers of daphnia (water fleas) from fresh water or from a commercial fish supplier.
David is an ex-lecturer in Environmental / Biological Sciences.
He has written for most of the UK gardening magazines, including the RHS.
Forest Edge’s garden has been widely covered in magazines and has been featured in a BBC’s Gardeners’ World special.
He also maintains a blog at https://nwhwildlife.org/