Cobwebs

 

 

Vorsø 1975-87
Araneid spider in its web, covered in morning dew, woven between stems of rosebay willow-herb (Chamaenerion angustifolium), Jutland, Denmark. (Photo copyright © by Kaj Halberg)

 

 

Jylland 1991-95
Following a night with heavy dew, it is clearly revealed, how many webs of common hammock-weaver (Linyphia triangularis) are adorning this common box (Buxus sempervirens), Jutland, Denmark. (Photo copyright © by Kaj Halberg)

 

 

Nordindien 1982
Silken nest of an unidentified moth, shimmering in the sunshine, Keoladeo National Park, Rajasthan, India. (Photo copyright © by Kaj Halberg)

 

 

Araneid cobwebs, suspended from a gutter, Funen, Denmark. The plant is a hollyhock (Alcea rosea). (Photo copyright © by Kaj Halberg)

 

 

On a quiet October day, myriads of young spiders have landed in this meadow in Nature Reserve Tipperne, Ringkøbing Fjord, Denmark, where their silk threads create a transparent carpet, as far as the eye can reach. (Photo copyright © by Kaj Halberg)

 

 

 

Spiders

 

The book Svenska Spindlar, in Latin Aranei Svecici (‘Swedish spiders’), published 1757, was the first comprehensive book on the spiders of Sweden and one of the first regional monographs of a group of animals worldwide, written by Swedish arachnologist and entomologist Carl Alexander Clerck (1709-1765).

The full title of the book is quite laborious, being Svenska Spindlar uti sina hufvud-slägter indelte samt under några och sextio särskildte arter beskrefne och med illuminerade figurer uplyste – Aranei Svecici, descriptionibus et figuris æneis illustrati, ad genera subalterna redacti, speciebus ultra LX determinati (‘Swedish spiders into their main genera separated, and as sixty and a few particular species described and with illuminated figures illustrated’).

 

 

Title page of Carl Alexander Clerck’s book Svenska Spindlar. (Illustration: Public domain)

 

 

Fyn 2010-17
Dust-covered cobwebs in a stable window, Funen, Denmark. (Photo copyright © by Kaj Halberg)

 

 

Filippinerne 1984
Raindrops create a beautiful pattern in a cobweb, Luzon, Philippines. (Photo copyright © by Kaj Halberg)
 

 

 

Flowers, fallen from a mu oil tree (Vernicia montana), have been caught in cobwebs, Sanyi, Taiwan. In the bottom picture, a puff of wind makes the flower sway. This tree is described on the page Plants: When the mu oil tree is flowering. (Photos copyright © by Kaj Halberg)

 

 

Kenya 1988-89
Numerous spider webs in a bush, shimmering in the sunshine, Lake Bogoria, Kenya. (Photo copyright © by Kaj Halberg)

 

 

Rain drops in a cobweb, Mingtsih, Taiwan. (Photo copyright © by Kaj Halberg)

 

 

Taiwan 2010
A tiny spider in its web, spun between two stems of common bamboo (Bambusa vulgaris), Basianshan National Forest, Taiwan. (Photo copyright © by Kaj Halberg)

 

 

Jylland 1977-90
Rime, covering a single thread of a cobweb, Jutland, Denmark. (Photo copyright © by Kaj Halberg)

 

 

Cobweb with dew, Cascade Range, California. (Photo copyright © by Kaj Halberg)

 

 

Autumn is the time, when young spiders spread. They climb to the top of vegetation, where they spin a disperse-thread, waiting for a puff of wind to carry them out into the world. It often happens that thousands of young spider land on a field, where their silk threads form a transparent carpet.

 

 

Young spiders, huddled together in their web before they disperse, flying with the wind at the end of a silk thread, which they spin themselves. – Horsens Fjord, Denmark. (Photo copyright © by Kaj Halberg)
 

 

 

Jylland 1977-90
Jylland 1977-90
Jylland 1977-90
On a quiet October day, myriads of young spiders have landed in this meadow in Nature Reserve Tipperne, Ringkøbing Fjord, Denmark, where their silk threads create a transparent carpet, as far as the eye can reach. (Photos copyright © by Kaj Halberg)

 

 

 

Araneidae Araneid spiders
This cosmopolitan family, comprising more than 3,000 species, is well-known to most people, as many of these spiders are quite colourful, and their webs are often found in gardens and along roads. Initially, araneid spiders make a framework of non-sticky threads, before adding final spirals of threads, covered in sticky drops.
 

These spiders are also called orb-weavers, from the old English word orb, meaning ‘ball-shaped’ or ‘circular’, in this case referring to the circular webs, which are suspended among vegetation, in fences, and other places.

 

 

Taiwan 2010
Taiwan 2010
Araneid cobwebs in a tree, Malabang National Forest, Hsinshu, Taiwan. The reddish colour in the background are young leaves of a maple species (Acer). (Photos copyright © by Kaj Halberg)

 

 

Jylland 1967-76
Araneid cobweb with dew drops, Nature Reserve Tipperne, Ringkøbing Fjord, Denmark. (Photo copyright © by Kaj Halberg)

 

 

Sjælland 2012-16
An araneid spider in its web, which is not quite completed, Zealand, Denmark. (Photo copyright © by Kaj Halberg)

 

 

USA 2012a
Araneid cobweb, covered in dew drops, woven between wires in a fence, Great Smoky Mountains National Park, Tennessee, United States. (Photo copyright © by Kaj Halberg)

 

 

Vorsø 1975-87
A marbled orb-weaver (Araneus marmoreus), cleaning its web of seeds of rosebay willow-herb (Chamaenerion angustifolium), Nature Reserve Vorsø, Jutland, Denmark. (Photo copyright © by Kaj Halberg)
 

 

 

Unfinished webs of araneid spiders, Taiwan (top), and Horsens Fjord, Denmark. (Photos copyright © by Kaj Halberg)

 

 

Californien 2011a
Morning dew in a web of an araneid spider, Jughandle State Park, California. (Photo copyright © by Kaj Halberg)

 

 

Vorsø 1975-87
The wind has blown numerous seeds of rosebay willow-herb (Chamaenerion angustifolium) into this cobweb of an araneid spider, Nature Reserve Vorsø, Jutland, Denmark. (Photo copyright © by Kaj Halberg)

 

 

Small araneid spider, Funen, Denmark. (Photo copyright © by Kaj Halberg)

 

 

In the town of Anping, southern Taiwan, aerial roots of a giant large-leaved fig (Ficus superba) have completely enveloped a former warehouse of the company Tait & Co. Today, the building is called Anping Tree House. Other pictures from this building are shown on the page Plants: Urban plant life, whereas large-leaved fig and other fig species are presented on the page Plants: Ancient and huge trees.

 

 

Sunshine, reflecting all colours of the rainbow in the web of an araneid spider, Anping Tree House. (Photo copyright © by Kaj Halberg)

 

 

 

Genus Argiope
Members of this genus of araneid spiders, comprising about 90 species, are distributed in all warmer areas of the world. Their web is quite large and often rather invisible, with the exception of a pure white silk pattern in the centre, made from densely woven threads, which form an X or a zig-zag pattern.

The spider sits with one pair of legs in each of the four directions of the X, or aligned with the zig-zag pattern. This often makes the animal extremely visible, and many scientists have speculated as to what purpose this pattern is made. One theory is that its visibility might prevent large animals from accidentally destroying the web. Research has also shown that the pattern reflects ultra-violet light, which may attract prey to the web.

 

 

Afrika 1980-81
Argiope lobata is widely distributed in Africa, southern Europe, and western Asia. This one was photographed in Zaire. (Photo copyright © by Kaj Halberg)

 

 

Costa Rica-2
This Argiope in Cahuita, Limón, Costa Rica, has caught a bush-cricket and is now entangling its prey in silk threads. (Photo copyright © by Kaj Halberg)

 

 

Costa Rica-2
Another Argiope from Cahuita. (Photo copyright © by Kaj Halberg)
 

 

 

Bali 2009
Web of a small Argiope in a field of young rice plants, Bali, Indonesia. Its legs are aligned with the zig-zag pattern. (Photos copyright © by Kaj Halberg)

 

 

Costa Rica-2
This Argiope is sitting in its web, its legs aligned with the X-shaped figure, Parque Nacional de Cahuita, Limón, Costa Rica. (Photo copyright © by Kaj Halberg)

 

 

Costa Rica
The pattern of silk threads in the web of this small Argiope is indeed conspicuous, but the spider itself is well camouflaged. – Reserva Nacional Hacienda Baru, Costa Rica. (Photo copyright © by Kaj Halberg)

 

 

 

Genus Nephila
Another striking genus of araneid spiders, called golden orb-weavers. Comprising about 23 species, these animals are distributed in tropical and subtropical regions around the world. The female, which is many times larger than the male, can grow to 6 cm in body length, with a leg span up to 15 cm.

The generic name is derived from the Greek nein (‘to spin’) and philos (‘love’), thus ‘fond of spinning’. The web of these spiders is enormous, up to 2 m across, with supporting strands much longer. The webs of different females are sometimes inter-connected, together covering many square metres. Small birds and bats are reported to have been caught in these strong webs.

 

The Asian golden orb-weaver (Nephila pilipes) is widespread, distributed from India and Sri Lanka eastwards to southern China, Taiwan, and Japan, and thence southwards to Australia.

Once, when I was hiking up the Marsyangdi Valley in central Nepal, I observed some children throwing something at female hikers, who then screamed and ran for dear life, while the children were laughing heartily. When I asked the children what they were doing to the poor tourists, they showed me several large orb-weavers, which they had collected from nearby webs.

 

 

Taiwan 2009
Taiwan 2011
Dorsal views of female Asian golden orb-weavers. They were encountered in Taiwan, where this species is very common in the lowlands and lower mountains. (Photos copyright © by Kaj Halberg)
 

 

 

Taiwan 2014d
Taiwan 2011
Ventral views of females, Taiwan. In the upper picture, a tiny male is seen to the left. (Photos copyright © by Kaj Halberg)

 

 

Taiwan 2009
Female Asian golden orb-weaver, sitting in her huge web, Taiwan. Remains of prey are seen above. (Photo copyright © by Kaj Halberg)

 

 

The golden-legged orb-weaver (Nephila inaurata, by some authorities placed in the genus Trichonephila) is found in southern Africa and Madagascar, and on several Indian Ocean Islands. It may be identified by its primarily golden front legs.

 

 

This female golden-legged orb-weaver, surrounded by tiny males, was photographed on Grand Comore, Comoro Islands. (Photo copyright © by Kaj Halberg)

 

 

American golden orb-weaver (Nephila clavipes, by some authorities placed in the genus Trichonephila) is found in a huge area, from the United States southwards to southern South America.

 

 

Dorsal view of a female American golden orb-weaver, Reserva Nacional Hacienda Baru, Costa Rica. (Photo copyright © by Kaj Halberg)

 

 

 

Linyphiidae Hammock-weavers
These small spiders, also called sheet-weavers, live almost worldwide, counting more than 4,300 species. Their common names stem from their densely woven web, which resembles a hammock or a sheet. Another popular name of this group is money spiders, from an old European superstition, claiming that if a sheet-weaver spider would run over a person, it would spin new clothes for you – meaning good fortune, moneywise.

 

 

Californien 2013b
Morning dew in a hammock-weaver web, Ronald W. Caspers Wilderness Park, Santa Ana Mountains, California. (Photo copyright © by Kaj Halberg)

 

 

Another hammock-weaver web with dew drops, Dasyueshan National Forest, Taiwan. (Photo copyright © by Kaj Halberg)

 

 

The common hammock-weaver (Linyphia triangularis) was first described by Swedish entomologist and arachnologist Carl Alexander Clerck (1709-1765) in his 1757 book Svenska Spindlar (see above).

This small spider, growing to 6 mm long, is abundant throughout Europe, and has also been introduced to north-eastern United States. It lives in low vegetation, where it spins a horizontal sheet-web, waiting on the underside for prey. Small insects, which climb on a maze of web threads above the horizontal sheet-web, may fall down onto the sheet, where they are killed by the spider.

 

 

Thousands of common hammock-weaver cobwebs in a field of rapeseed, covered in dew drops, Jutland, Denmark. (Photo copyright © by Kaj Halberg)

 

 

Jylland 1991-95
Numerous webs of common hammock-weaver among common hair-grass (Deschampsia flexuosa), Jutland, Denmark. (Photo copyright © by Kaj Halberg)

 

 

Jylland 1991-95
Following a night with heavy dew, it is clearly revealed, how many common hammock-weaver webs are adorning this common box (Buxus sempervirens), Jutland, Denmark. (Photo copyright © by Kaj Halberg)

 

 

Hammock-weaver cobwebs in a marsh thistle (Cirsium palustre), heavy with dew, Horsens Fjord, Denmark. (Photo copyright © by Kaj Halberg)

 

 

Sverige 2015
Webs of common hammock-weaver among grass and heather (Calluna vulgaris), Öland, Sweden. (Photo copyright © by Kaj Halberg)

 

 

 

Tetragnathidae Long-jawed spiders
A large family with about 50 genera and 1,000 species, found across the globe, except in the polar regions.

 

One member of the family is the European cave spider (Meta menardi), which is distributed from Scandinavia and Britain southwards to North Africa, and thence eastwards to Korea and Japan. Adults shun light, living in dark places, such as caves, tunnels, and mines, but will emerge around dusk to hunt, often using a single silk lasso line, which is thrown on their prey.

 

 

This picture is from Helligdomsklipperne, Bornholm, Denmark, where the European cave spider has survived in coastal caves for at least 12,000 years. (Photo copyright © by Kaj Halberg)

 

 

 

Moths

 

 

Nepal 2002
Caterpillars of an unidentified moth, huddled together in their communal web in a barberry bush (Berberis), whose leaves they have eaten, Langtang National Park, Nepal. (Photo copyright © by Kaj Halberg)

 

 

Rufous treepie (Dendrocitta vagabunda), searching for caterpillars in a dense cluster of cobwebs, Ranthambhor National Park, Rajasthan, India. This colourful member of the crow family is native to the Indian Subcontinent, southern China, and Indochina. (Photo copyright © by Kaj Halberg)

 

 

 

Notodontidae
A huge family with several subfamilies, many genera, and about 3,800 species, distributed across the globe, with a core area in the New World tropics.

 

Processionary moths are members of the subfamily Thaumetopoeinae. They got their name from the behaviour of the caterpillars, which march in long columns through the forest, each larva with a firm grip on the rear end of the preceding one (except the leading animal, of course). These marching caterpillars are on their way to pupate in the ground. They are very conspicuous, and would seemingly be vulnerable to enemies. However, they are protected from predators by their severely irritating hairs, which sometimes cause allergies in people.

As its name implies, the pine processionary moth (Thaumetopoea pityocampa) lays eggs on pines, and the larvae, which live communally in large silken nests, are highly destructive to pine forests, often defoliating entire growths. Previously, this species was native to southern Europe, North Africa, and the Middle East, but the global warming has had the effect that it is spreading northwards, and is now found as far north as northern France.

French entomologist Jean-Henri Fabre (1823-1915) conducted a famous study on the pine processionary caterpillar, described in his book The Life of the Caterpillar (1916). In this experiment, a group of caterpillars marched head-to-tail in a circle around the rim of a flower pot, continuing for a week. He concluded that the caterpillars were mindless automatons, trapped because they were pre-programmed to blindly follow the trail of the preceding animal.

 

 

Silken nest of pine processionary moth in a pine, Etna, Sicily. (Photo copyright © by Kaj Halberg)

 

 

Marching caterpillars of pine processionary moth, near Castelbuono, Sicily. This column contained almost 200 animals. (Photos copyright © by Kaj Halberg)

 

 

 

Yponomeutidae Ermine moths
This family, divided into 5 or 6 subfamilies, contains several hundred species, most of which live in tropical areas.

 

The genus Yponomeuta contains more than a hundred species, some of which are agricultural pests.The native range of the spindle ermine moth (Y. cagnagella), in America known as euonymus webworm, is throughout Europe and the Middle East, eastwards to Siberia. It has also become naturalized in north-eastern North America. The adult moth has a wingspan, ranging from 19 to 26 mm.

The host plant of this species is the European spindle tree (Euonymus europaeus). The caterpillars are gregarious, spinning silk webs and feeding on the leaves within them. When the larvae pupate, they spin silk cocoons around themselves, hanging vertically inside the web. These caterpillars often occur in such numbers that the host tree becomes completely defoliated. In such cases, the larvae spin silk threads to the ground, where they pupate under plants.

 

 

Bornholm 1977-96
Caterpillars of the spindle ermine moth are very characteristic, yellowish-white with black spots along the sides. These, encountered on the island of Bornholm, Denmark, have almost defoliated a spindle tree. (Photo copyright © by Kaj Halberg)

 

 

 

(Uploaded February 2018)

 

(Latest update October 2022)