About the Trap Grounds

The Trap Grounds Town Green & Local Wildlife Site in north Oxford lies immediately south of the Frenchay Road canal bridge (nearest postcode OX2 6TF). An information board on the towpath marks the entrance to three acres of reed bed and seven acres of woodland, grassland, stream, and ponds. The site (open to visitors 24/7) is owned by Oxford City Council and managed for conservation, recreation, and education by the Friends of the Trap Grounds, a group of local volunteers. For more information about current events and activities, the history and wildlife status of the site, and our campaign to save it as a Town Green, visit You can also contact the Secretary via the website.

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Thursday, September 26, 2019

Brown Hairstreak butterfly and Emerald damselfly

Belatedly catching up with some of Nicola Devine's most notable photos from earlier this summer ...

Brown Hairstreak (Thecla betulae) is a conservation priority species, in severe decline all over the country, but Nicola has photographed it on the Trap Grounds in every year since 2015. Its larvae need Blackthorn to feed on; we planted several Blackthorn trees five or six years ago, and it has paid off.

Brown Hairstreak butterfly (Trap Grounds, 20 August 2019, Nicola Devine)

Emerald Damselfly (Lestes sponsa): this mating pair were spotted on 23 July. The last of all damselflies to emerge, this is a late-summer species; the eggs won't hatch until next Spring. Emeralds colonise shallow pools that temporarily dry out in summer, which is just as well, because our Dragonfly Pool dried up completely during the August/September drought.

Emerald damselflies mating (Trap Grounds, Nicola Devine, 23 July 2019)

Wednesday, September 18, 2019

Rhinoceros beetles

These beetles were found in May on a rotten tree stump on the Trap Grounds during our Springwatch Family Day by a pupil at St Philip & St James primary school, but until today we did not know his name. Today I had the pleasure of meeting Karim Chibane and congratulating him on his significant find. According to beetles expert Linda Losito, Rhinoceros beetles, members of the scarab family, have been reported only once before in Oxford (on the Lye Valley nature reserve).

Rhinoceros beetles (Alan Allport, Trap Grounds, May 2019)

Friday, September 13, 2019

A fox in the sun

Clare Weiner writes: "Today (September 13th) about 5.45pm, I spotted a Fox in the meadow by the school fence. It ran off, but we saw it again later, boldly out in the midst of the mown meadow, in the sunshine. A family with a dog (on a lead) were nearby. I told them there was a fox ahead, and we all stopped, and the fox stood still to be photographed. It seemed in very good condition, better than many urban foxes, and so bold."

[Dog owners, please respect the wildlife and keep your dog on a lead. -- C. Robinson]

Trap Grounds fox (Clare Weiner, 13.09.19)

Banded Demoiselle

Banded Demoiselle

Clare Weiner writes: "On 22 August, Nicola Devine and I saw this Banded Demoiselle (female) perch on a small dead branch of a willow growing by the Mill Stream. These Damselflies (we know it is a Damselfly as its closed wings are lying along its back) like slow-flowing streams, so the location was perfect for it. Unlike most damselflies, the wings are not colourless but a pale brownish green in the female, which has a green body. The males are much more colourful, with an iridescent turquoise body and blue veins in the wings."

Banded Demoiselle (f.), Trap Grounds (Clare Weiner, 22.08.19)

Spotted Flycatcher

Nicola photographed this rare visitor to the Trap Grounds today. In the UK, numbers of Spotted Flycatchers fell by 85 per cent between 1970 and 2015. So this was an honoured guest. 

Spotted Flycatcher, Trap Grounds, Nicola Devine, 13.09.19

Water Rail

It was Nicola's lucky day. Besides the Spotted Flycatcher, she got a glimpse of our most elusive resident, the Water Rail. More often heard than seen, uttering a high-pitched squeal from the depths of the reedbed, it rarely ventures out into the open. Perhaps the warm autumn sunshine tempted it out?

Water Rail, Trap Grounds (Nicola Devine, 13.09.19)

Tuesday, September 10, 2019

Elephant Hawkmoth caterpillar (Dielephila elpenor)

Caterpillar of the Elephant Hawkmoth (C Robinson, Trap Grounds, 7 Sept 2019)

Spotted by Alan Allport on 7 September feeding on Rosebay Willowherb. Three inches long! It will pupate in a couple of weeks' time and overwinter under the ground; but will we see the spectacular pink-winged adult next summer? Not likely, because it is a nocturnal moth.

Friday, September 6, 2019

Red Admiral (Vanessa atalanta)

Autumn approaches, but butterflies are still plentiful on the Trap Grounds. Nicola photographed this Red Admiral (which she describes as "bold and brassy") on a Buddleia bush on 1 September. The most important food plant for the larva is Common Nettle - of which there is no shortage on the TG.

Red Admiral, Trap Grounds, 1 September 2019 (Nicola Devine)

Common Green Grasshopper (Omocestus viridulus)

On the following day Nicola photographed this Common Green grasshopper (male), sharing a leaf with an unidentified wasp. The males display to females by rubbing their legs against their wings to create a loud churring noise known as 'stridulation'. After mating, the eggs are laid in the soil ready to hatch the following spring.

Common Green Grasshopper, Trap Grounds, 2 September 2019 (Nicola Devine)