March 14

National Save a Spider Day

A conservation observance on March 14 promoting spider-friendly practices and countering misconceptions about their ecological role.

Yearly Date

March 14

Observed in

United States

Introduction

The case for National Save a Spider Day is backed by hard data. A 2017 study published in The Science of Nature estimated that the global spider population consumes between 400 and 800 million metric tons of insects and other invertebrates every year, a figure comparable to the total annual meat and fish consumption of all humans on Earth.

Despite that staggering contribution to pest control, spiders remain among the most casually killed animals in domestic settings. Fewer than 30 of the roughly 50,000 known species pose any medical risk to humans, yet the reflexive response to a spider sighting is still often a rolled-up newspaper rather than a glass and a piece of paper.

National Save a Spider Day History

The scientific study of spiders stretches back more than two millennia, but formal conservation attention to these animals is remarkably recent. Aristotle made the earliest known recorded observations of spider behavior around 350 BCE, noting how they constructed webs and captured prey. For centuries afterward, spiders appeared mainly in folk medicine and superstition rather than in structured scientific inquiry.

Modern arachnology took shape in 1757 when Swedish naturalist Carl Alexander Clerck published Svenska spindlar, a work that described 65 spider species with standardized names and detailed illustrations. Clerck's taxonomy predated even Linnaeus's treatment of spiders and established the framework that researchers still build on today. By the late 1800s, taxonomists had described thousands of species across multiple continents.

A Hidden Biomass

The sheer scale of the global spider population remained poorly quantified until the 21st century. Scientists now estimate that approximately 25 million metric tons of spiders inhabit the Earth, distributed across roughly 50,000 described species in more than 130 families. Some researchers believe the actual species count could exceed 120,000, with many undocumented species in tropical forests and cave systems.

Fear Versus Ecological Value

Arachnophobia, clinically defined as an intense and irrational fear of spiders, affects an estimated 3 to 6 percent of the global population and is one of the most common specific phobias. Exposure therapy achieves success rates of 80 to 90 percent, yet the fear persists in popular culture through media portrayals that amplify danger. People with arachnophobia perceive spiders to be 30 to 50 percent larger than their actual size, according to clinical research, compounding the disconnect between real risk and emotional response.

A Day Without a Documented Founder

National Save a Spider Day began appearing on online holiday calendars in the early 2000s, but no primary documentation identifies a founder, establishing organization, or formal proclamation. The observance is widely attributed to conservationists and entomologists who sought to counter the reflexive killing of household spiders and promote their ecological value. Without an institutional sponsor, the day has grown organically through wildlife educators, science communicators, and pest management professionals who recognize spiders as allies rather than threats.

National Save a Spider Day Timeline

~350 BCE

Aristotle records spider observations

Aristotle made some of the earliest recorded scientific observations of spiders in ancient Greece, describing their web-building behavior and feeding habits.

1757

First spider taxonomy published

Carl Alexander Clerck published Svenska spindlar, the foundational work of arachnological taxonomy, describing and illustrating 65 spider species with the first standardized naming system.

1972

American Arachnological Society founded

The American Arachnological Society was established to promote the scientific study of arachnids and foster collaboration between amateur and professional researchers.

2010

Darwin's bark spider silk described

Researchers described the silk of the Darwin's bark spider as the toughest biological material ever tested, reaching 520 MJ per cubic meter, more than ten times tougher than Kevlar.

2017

Global prey consumption study published

Researchers Martin Nyffeler and Klaus Birkhofer published a study in The Science of Nature estimating spiders consume 400 to 800 million metric tons of prey annually worldwide.

How to Celebrate National Save a Spider Day

1

Learn to identify common household spiders

Use the American Arachnological Society resources or your regional cooperative extension service to identify the spiders in your home. Most household species, including cellar spiders and cobweb spiders, are harmless and actively reduce mosquito, fly, and moth populations indoors.
2

Relocate instead of killing

Place a glass over the spider, slide a piece of paper underneath, and release it outdoors near ground cover or a garden. This simple catch-and-release method takes seconds and preserves an animal that consumes dozens of pest insects per week.
3

Build a spider-friendly garden habitat

Leave small patches of leaf litter, install log piles, and reduce pesticide use to create welcoming environments for garden spiders. The Xerces Society provides detailed guides on reducing pesticide impact on beneficial invertebrates including spiders.
4

Watch a documentary on spider biology

Stream documentaries like PBS's Spider Power to see orb weavers, jumping spiders, and trapdoor spiders in action. Understanding how spiders hunt, build, and communicate makes it easier to appreciate their role in your local ecosystem.
5

Donate to invertebrate conservation research

Support organizations like the Buglife conservation charity, which funds habitat protection for at-risk invertebrates including spiders. Even small contributions help fund species surveys and habitat restoration projects that benefit arachnid populations.

Why We Love National Save a Spider Day

A

Spiders provide billions of dollars in pest control

The 2017 Nyffeler and Birkhofer study calculated that spiders eliminate 400 to 800 million metric tons of insects annually, with forests and grasslands accounting for over 95 percent of that prey kill. This natural pest suppression reduces reliance on chemical pesticides in both agricultural and residential settings.
B

Spider conservation is critically underfunded

The IUCN Red List has assessed only 301 spider species, of which 164 are categorized as threatened, yet spiders receive a fraction of the conservation funding directed at vertebrates. In Europe, only one species, the Gibraltar funnel-web spider, has continent-wide legal protection despite 178 species appearing in national legislation.
C

Spider silk drives biomedical innovation

Dragline silk has a tensile strength five times greater than steel of the same diameter, and Darwin's bark spider silk reaches a toughness of 520 MJ per cubic meter, more than ten times tougher than Kevlar. Researchers are engineering recombinant spider silk proteins for surgical sutures, tissue scaffolds, and biodegradable high-performance textiles.