Though the month may be high summer for us it’s very much the start of the autumn rush for many of our birds, though some species will still be on second or third broods. We’re likely to say farewell to the Swifts over our homes as they start to head south, though birds can be seen into September over some of our reservoirs where such feeding birds may include birds that have bred farther north.
The second half of the month and into early September will see many summer visitors moving through, some fattening up on fruits such as Elderberries and Blackberries, including many normally insectivorous Warblers.
This is the time to scour your local patch for migrants that don’t breed locally such as Wheatears, Whinchats, Yellow Wagtail (check areas with horses or playing fields), Redstart and both Flycatcher species, with Spotted Flycatcher the more frequent.
Last year the urban oasis of Walpole Park held a male Pied Flycatcher for several days and also a male Redstart. Places such as Horsenden Hill, Warren Farm and Yeading Brook Meadows are likely to produce some of these though you may be very fortunate to get a Flycatcher or Redstart in your garden!
Waders are also on the move and a good time to catch up with Green and Common Sandpipers which are regular through the London area. Sites such as Brent Reservoir and the London Wetland Centre are regular spots for them but any water body has the potential if not too disturbed.
A warm summer’s day will be full of the sound of buzzing insects. Orthoptera, the order of Grasshoppers, true Crickets (not normally found locally other than escapes from pet food!) and Bush-Crickets, should all be mature now.
Grasshoppers can be distinguished by having short antennae. The males produce their songs, technically known as stridulation, by rubbing one of the hind legs with special stridulatory pegs against the opposite wing’s hard edge. In our meadows, the most abundant Grasshopper will be the Meadow Grasshopper. Field Grasshoppers, which are common, prefer drier situations and are the species most often encountered in urban gardens. Also, look out for Lesser Marsh Grasshoppers in meadows. The structure of keels on top of the thorax is useful in identifying Grasshopper species.
Bush-Crickets have very long antennae. Females have very obvious blade-like ovipositors at the rear end which grasshoppers lack. Bush-Crickets have higher-pitched songs than the Grasshoppers and make their sound by rubbing their fore-wings together with a scraper-like device on one against a ridge on the other wing. Most common in our gardens are the dumpy Speckled Bush-Cricket and the Two Oak Bush-Cricket species, with the recently naturalised Southern Oak Bush-Cricket now the most numerous. These two species are attracted to light so not infrequently found indoors.
In our meadows, the two most frequently encountered species are Roesel’s Bush-Cricket and Long-winged Coneheads, both formerly rare species, which are now very common in the southeast and beyond. Old hedges may also hold Dark Bush-Cricket, our remaining regular species. Bat detectors will help you hear them if like me they are no longer audible to you!
Look out for new broods of Butterflies such as Common Blue, Brown Argus and Small Copper. As I write this Warren Farm already has good numbers of Brown Argus showing. Good varieties of moths should still be found.
Hummingbird Hawkmoths and Jersey Tigers may be seen during the day, while in moth traps more obvious species such as Red Underwing, Copper Underwing, Canary-shouldered Thorn and Tawny Speckled Pug may be seen.
Migrant Hawkers are the last of the dragonflies to emerge. They first appear mid-July but it is August and September when they are at their peak. They are smaller than the other related hawkers such as Southern and Brown Hawkers which should be common still along with increasing numbers of Common Darters over our wetlands, meadows and sunny woodland rides.
Small young Slow Worms should be around now, about 4cm long. Old gardens and allotments are good places for this our most likely encountered native reptile in the borough. Young Grass Snakes will also be emerging from their eggs this month. These eggs are laid in decomposing vegetation, including compost heaps, where the eggs get sufficient warmth. Probably restricted to isolated locations such as along the Yeading Brook in the borough but more widespread in neighbouring Hillingdon and found in places such as Richmond Park.
What to see each month is written by EWG member and naturalist Neil Anderson.