Disguise or surprise: Spider antipredator responses as a function of the architecture of their webs

Wednesday, November 16, 2022

11:28 AM – 11:41 AM PT

Location: Vancouver Convention Centre, Meeting Room 109

Presenting Author(s)

AH

Andrea M. Haberkern

The University of British Columbia
Vancouver, British Columbia, Canada

Co-author(s)

JS

Jessica C. Schmidt

The University of British Columbia
Vancouver, British Columbia, Canada
YZ

Yi Lin Zhou

The University of British Columbia
Vancouver, British Columbia, Canada
Luis Camacho

Student
Universitat Autònoma de Barcelona
AB

Antonio D. Brescovit

Instituto Butantan
São Paulo, Brazil
LA

Leticia Aviles

The University of British Columbia
Vancouver, British Columbia, Canada

Animals exhibit a variety of strategies to avoid predation; spiders are no exception. We explored whether web-building spiders that differ in the architecture of their webs exhibit morphologies and behaviours suggestive of antipredator strategies that trade off with the degree of protection offered by their webs. Spiders build webs of three different types: the more protected 3D tangles and 3D sheet-and-tangles, and the more exposed 2D orbs, with or without a refuge. We hypothesize that spiders whose webs offer greater protection—a 3D architecture or a refuge, will be less likely to be armoured or brightly coloured when compared to spiders without these protections. We collected data on 400+ spiders and their webs in two Ecuadorian Amazon rainforest sites. We show that 2D web-builders with no refuges tended to be brightly coloured (background contrasting) and spiny (spiky), whereas those with refuges tended to blend against the background of their refuges. 3D web-builders, on the other hand, were neither cryptic nor brightly coloured, nor armoured, and were more likely to drop out of the web upon simulated predator contact. These results support the hypothesis that web-building spiders tend to be protected either through the architecture of their webs or their morphology and behaviour, suggesting a trade-off between different types of antipredator strategies.