Saturday 21 August 2021

Wasp Spiders, butterfly influxes and more at Cranford Park

The high light of my visit to Cranford Park yesterday was finding a glorious huge female Wasp Spider. Unfortunately I could only get a photo of her under carriage, rather than the top of her which is intricately patterned just like a wasp. The females are larger and more colourful than the small drab brown males. The females are quite ferocious, but only to the males and their prey, they are completely harmless to us humans. 
Females are known to eat the males if they dont get out of the way quick enough after mating. 

I have seen these colourful spiders at Cranford Park before, but not for a few years. I could only find one yesterday and hope to find some more on my next visit. 

They spin unusual webs with a distinct zig zag pattern from the centre of the web down to the bottom. This specimen that I found was lacking the zig zag effect, but it had rained during the night so she was slowly rebuilding her net ... 

The under carriage. You can see the appendage where the silk comes out. 

 The butterfly transect was good, It revealed Cranford Park is experiencing a second flush of both Small Copper and Brown Argus, which I dont always see each season. They were very fresh looking specimens, and as tiny as ever which made counting them very difficult at times. 

I had a total of 68  butterflies of 10 species, a bit down from my last count on 4th August when I had 115 butterflies of 13 species but it was much cooler and overcast yesterday. 

Recorded 20/08/21
Large White
Small White
Small Copper
Brown Argus
Common Blue
Holly Blue
Red Admiral
Speckled Wood
Meadow Brown

and here come the pics .... 


tatty male Meadow Brown 

Red Admiral on the information board by the wildlife pond.
I'm not sure if the Peacock illustration
 confused it or not

Red Admiral

Red Admirals

Small Copper

Small Copper

Small Copper

Brown Argus

Brown Argus

Brown Argus

Brown Argus

Along with the huge Volucella hoverflies I spotted on my last visit, yesterday my eye was caught by one of the smallest hoverfly species, Sphaerophoria scripta, just 5mm long and very addictive to watch ... 

You can tell autumn is on it's way as various fungi have started to spout. 
I found several clumps of this coral fungi, which I believe to be Clauvulina coralloides aka Crested Coral ....

There is one place in the woods where you can get guaranteed views of the Yellow Stagshorn fungi (Calocera viscosa) every season, and yesterday did not disappoint ....

The young oaks along the river Crane are showing signs that a gall wasp has been busy. These are Silk Button galls caused by the Neuroterus numismalis gall wasp. They have two generations each year, one being sexual and the other being agamic (ie no males needed to reproduce). The sexual generation cause Blister galls on oak leaves, but the agamic generation produce these delicate looking Silk Button galls .... 

The larva in each tiny gall matures in August but they stay in the gall even when the leaves drop in autumn, finally emerging as an adult the following spring .... 

After my transect I like to walk along the river and hope for a glimpse of one of the Kingfishers. No luck yesterday but this young juvenile Green Woodpecker was on the path, along with a racing pigeon ...

 It being a week day, the park was fairly quiet which meant the local rabbits were more easily seen ....

and the Grey Squirrels by the large oaks, who are never shy, were busy feeding up .... 

St Dunstans was fairly quiet. Every year we get Magpies breeding in the conifers and they tend to deplete the graveyard of any butterflies, so I dont do any counts there. This is one of this years youngsters ....

Robins nested in the remainder of the maze hedges in the courtyard this season. This is one of the adults looking a bit neater and tidier now his/her brood have flown the nest ...

After my last blog where I was uncertain whether Buzzards bred in the woods, Tony James contacted me to confirm he and his lovely missus had spotted food passes between adults and juveniles over the park, so it looks as if Common Buzzards did indeed breed in Cranford Park this year, which is really great news. 

Yesterday afternoon there was a Little Owl calling near the old sweet chestnut tree, but despite a lot of searching I never did manage to locate it, so have no idea if it was a juvenile or adult, but it's comforting to know they are still there. 

As always, a great visit to the park, with plenty to see including some of the regulars like Phil with his two adorable dogs, Ellie and Scruffy, and of course Martyn who is always being kept busy these days :) And it was good to know that one of the other regulars, Meena, had spotted the caterpillar of the Elephant Hawk-moth near the river recently. A great find for the park. 

Thursday 5 August 2021

Summer at Cranford Park (and a few other bits and pieces)

I carried out two UKBMS transects at Cranford Park recently, with very differing results as you can see from the figures below. Some species of butterfly emerge at different times to others, so my records often flag up something I havent seen for a year, or show when a season has ended for another. Temperature also plays a part in records, and even wind direction can affect how many are seen and counted. 

20/07/21 temp 27c
Small / Essex Skipper * x 37
Large Skipper x 4
Large White x 28
Small White x 10
Small Copper x 5
Common Blue x 1
Brown Argus x 1
Red Admiral x 4
Peacock x 3
Comma x 3
Speckled Wood x 9
Gatekeeper x 16
Meadow Brown x 46
Total 164 butterflies of 12 species

04/08/21 temp 20c
Small / Essex Skipper * x 3
Large White x 10
Small White x 1
Green-veined White x 2
Brown Argus x 1
Holly Blue x 3
Red Admiral x 9
Peacock x 5
Comma x 3
Silver-washed Fritillary x 1
Speckled Wood x 6
Gatekeeper x 38
Meadow Brown x 33
Total 115 butterflies of 13 species

* Small and Essex Skippers can only be told apart by the colour of their antennae tips so are often grouped together for count purposes

You'll notice I have high-lighted the Silver-washed Fritillary. That is because this is only the 4th record since the UKBMS scheme began at Cranford Park in 1999. Alison Shipley recorded one in August 2006 and I recorded two in August 2018. All of the ones recorded have been male. Hopefully one day a female will appear too, and we could have a beautiful breeding colony. 
The Silver-washed Fritillary is the largest of all the fritillaries and a little bigger than our commonly seen Red Admirals. They are strong flyers, and the one I watched yesterday often flew off above one of the nearby oak trees before swirling back down again. There are three different coloured buddleias at Cranford Park and this butterfly made a beeline for the white one nearly every time. Sadly it wasnt really in the mood to have his photo taken so the only captures I got were when it perched high in the buddleia and I had to stand on tip toe to get any image at all. 

So stand by for an influx of butterfly photos with identifications on each pic ...

tatty aged male Small Skipper

fresh female Essex Skipper

female Green-veined White

Brown Argus

Red Admiral

fresh Speckled Wood

back lit Speckled Wood

tatty Speckled Wood


male Silver-washed Fritillary

There is a lot of ragwort growing in the meadows at the moment, but very few Cinnabar moth caterpillars to be seen. These are guaranteed sights every summer, but our spring was a bit odd weather wise, so that may have had an impact. 

caterpillar of the Cinnabar moth

One year I will record every species of hoverfly I find at Cranford Park, but for now here are two of the largest that can be seen at this time of year. They may look large and scary, but they are completely harmless and a great indicator of the health of our enviroment. They are short-lived and fast breeding. 

Volucella zonaria

Volucella zonaria

Volucella pellucens

It has been a good summer for some of the breeding birds at Cranford Park. Song Thrushes made homes both near the wildife pond and the subway entrance. I witnessed one in July on the subway pavement, smashing a snail repeatedly against the kerb until the shell shattered. The photo below is of the successful Thrush with it's prize shell-less snail ..

A couple of weeks ago I sound recorded a bird calling with in the woods. I also managed one very poor photo. It turns out we had a family of Hobbys. This is really exciting as I havent recorded Hobbys nesting at Cranford for a few years now. They used to regularly breed at the park, but there favoured tree came down one year and they werent spotted for a very long time. Below is the terribly bad photo of a juvenile Hobby checking me out below it ... 

Red Kites have bred at Cranford Park this year, but at the Cranford Lane end of the park for a change...

Common Buzzards did build a huge nest within the woods, and I have seen them regularly flying and calling over that area, but I cannot confirm they actually bred (although I like to think they did). 

Usually in July I find our resident Kestrels in the meadows, teaching their youngsters how to hunt crickets and grasshoppers on the grassy paths, but this summer I havent spotted them (although a juvenile bird was seen in Avenue Park by the iron bridge recently). I have also not seen or heard the Little Owls for a couple of years now, something I always saw in late June or early July. 

Nearer to where I live at the moment (Harefield) Red Kites can often be seen from the lockdown loftroom window, and for the second year running there have been juveniles perched in the trees that line the Grand Union canal ....

and last week a male Sparrowhawk appeared in the back garden ....