Post by nomad on Sept 1, 2017 15:43:36 GMT
We never hear much about the Arachnida on the forum and they are often referred to as creepy crawlies, especially by the lovers of our winged beauties such as I, but the fact remains they play an irreplaceable role in our ecosystem. Although I was not especially looking for them, I could not fail to notice two different, good sized European orb weavers in the tussocks of tor grass on the chalk grassland. How many neat little wrapped bundles of prey did I find, including those that were iridescent blue and brown, the winged remains of Lysandra bellargus.
The Wasp Spider, Argiope bruennichi is a very large colourful spider that has arrived in the UK from the continent, being first recorded here in the 1920s and has slowly spread over the south of England. With milder winters as a result of climate change, this spider now appears to be expanding its range northwards. They build orb webs in grassland, and attach their silk egg-sacs to the grasses. The web has a wide, white zig-zag strip running down the middle, known as a 'stabilimentum', the function of which is unclear. Mating is a dangerous game for males; they wait at the edge of the web until the female has moulted into a mature form, then take advantage of her jaws being soft and rush in to mate. However, many males still get eaten during this time. I did not see the males only the large females.
Below. Argiope bruennichi females. Chalk Grassland. Wiltshire. August 2017.
Four-spotted Orb Weaver - Araneus quadratus builds its web in tussocks of grass close to the ground. The large female I photographed had just caught a bumble-bee, which was no match for this spider. Females can change their colour to match the resting surface. Nearby a much smaller male was making its way warily towards another female. (Image 2).
Below. Araneus quadratus
The Wasp Spider, Argiope bruennichi is a very large colourful spider that has arrived in the UK from the continent, being first recorded here in the 1920s and has slowly spread over the south of England. With milder winters as a result of climate change, this spider now appears to be expanding its range northwards. They build orb webs in grassland, and attach their silk egg-sacs to the grasses. The web has a wide, white zig-zag strip running down the middle, known as a 'stabilimentum', the function of which is unclear. Mating is a dangerous game for males; they wait at the edge of the web until the female has moulted into a mature form, then take advantage of her jaws being soft and rush in to mate. However, many males still get eaten during this time. I did not see the males only the large females.
Below. Argiope bruennichi females. Chalk Grassland. Wiltshire. August 2017.
Four-spotted Orb Weaver - Araneus quadratus builds its web in tussocks of grass close to the ground. The large female I photographed had just caught a bumble-bee, which was no match for this spider. Females can change their colour to match the resting surface. Nearby a much smaller male was making its way warily towards another female. (Image 2).
Below. Araneus quadratus
