Nursery web spider
Pisaura mirabilis
The nursery web spider is a common, slender spider known for its variable coloration and distinctive mating rituals. It does not build a web to catch prey but instead hunts actively among low vegetation and shrubs. Males are famous for presenting females with a silk-wrapped nuptial gift to avoid being eaten and to increase mating success. Females carry their egg sacs beneath their bodies and construct a protective silken tent, known as a nursery web, for their young.
Details
Identification
Slender body, often with a light median stripe on the prosoma; long and hairy legs; characteristic nursery web in the herb layer; female carries egg sac beneath the body.
Social behavior
Solitary; distinct mating behavior involving nuptial gifts; females exhibit intensive brood care.
Diet
Feeds on various insects such as flies, mosquitoes, and small grasshoppers, as well as other arthropods.
Hunting strategy
Active ambush predator; the spider waits motionless in the vegetation and pounces on passing prey.
Overwintering
Overwinters usually as subadults in leaf litter, moss, or under bark.
Ecology
Ecological role
Important predator of insects in terrestrial ecosystems such as meadows and forest edges.
Natural predators
Birds, lizards, larger spider species, parasitic wasps.
Competitor species
Other wolf spiders (Lycosidae) or nursery web spiders (Pisauridae) in the same habitat.
Ecosystem service
Biological pest control through the predation of a wide variety of insects.
Threats
Intensive agriculture, frequent mowing of meadows, loss of fringe structures, and habitat fragmentation.
Scientific profile
Profile
Distinguishing features
Slender body with very long legs. In a resting position, the first two pairs of legs are often stretched forward in parallel. Characteristic is the 'nursery web', a bell-shaped silk structure in the vegetation where the spiderlings are guarded. Females carry the spherical egg sac with their chelicerae under the prosoma.
Habitat
Diverse open to semi-open habitats: sunny meadows, forest edges, bogs, dunes, fallow land, and gardens with tall vegetation.
Role in food web
Important predator in the herb layer for regulating insect populations; serves as food for birds, lizards, and predatory insects such as spider wasps.
Protection & threats
Main threats
Intensification of agriculture (frequent mowing), loss of field margins/edge structures, and scrub encroachment of open-land habitats.
Population trend
Stable; the species is widespread and common throughout Europe.