# Blacklegged Tick (*Ixodes scapularis*)

> The blacklegged tick, also called the deer tick, is a tiny arachnid that attaches to hosts and feeds on blood, transmitting Lyme disease and other pathogens in eastern North America. Unfed nymphs are poppy-seed sized; adults are larger and most active in fall. Listed Not Evaluated by IUCN.

- **Category:** Invertebrate
- **Conservation status (IUCN):** Not Evaluated
- **Range:** Deciduous forest and grassy edges of eastern and midwestern United States and southeastern Canada — expanding northward with climate warming.
- **Canonical page:** https://globalanimalguide.org/animals/tick/
- **Last reviewed:** 2026-07-16

## Scientific classification

- **Kingdom:** Animalia
- **Phylum:** Arthropoda
- **Class:** Arachnida
- **Order:** Ixodida
- **Family:** Ixodidae
- **Genus:** Ixodes

## Facts at a glance

| Attribute | Value |
| --- | --- |
| Scientific name | Ixodes scapularis |
| Diet | Blood — feeds on mammals, birds, and reptiles |
| Habitat | Deciduous forests, leaf litter, and grassy edges of eastern North America |
| Lifespan | 2–3 years across larva, nymph, and adult stages |
| Weight | 1–5 mg (0.000001–0.000005 kg) depending on stage |
| Top speed | Slow crawler; waits on vegetation with legs outstretched |
| Conservation status | Not Evaluated (IUCN) |

## Three-host life cycle

Blacklegged ticks feed once at each life stage — larva, nymph, and adult — dropping off between hosts to moult. White-tailed deer are critical adult hosts that distribute ticks, while mice and birds infect nymphs with Lyme bacteria during larval and nymphal feeds.

## Questing behaviour

Ticks climb vegetation and extend front legs to latch onto passing hosts — a behaviour called questing. They detect carbon dioxide, heat, and vibration. Permethrin-treated clothing and DEET repellents reduce attachment during hiking.

## Lyme disease transmission

Ixodes scapularis is the primary vector of Borrelia burgdorferi, the bacterium causing Lyme disease in the United States. Nymphs — active in late spring and summer — cause most human infections because they are small and easily overlooked. Prompt tick removal within 24–36 hours reduces transmission risk.

## Expanding range

Climate warming and reforestation expand tick range northward and into Canada. Not Evaluated by IUCN, blacklegged ticks are a major public health concern rather than a conservation species. Landscape management and deer control can reduce local abundance.

## Frequently asked questions

### What is a deer tick?

Another name for the blacklegged tick (Ixodes scapularis) — named because white-tailed deer are important hosts for adult ticks, though deer do not transmit Lyme bacteria.

### How do you remove a tick?

Use fine tweezers to grasp the tick close to the skin and pull steadily upward without twisting. Clean the bite area and monitor for rash or fever.

### Do all ticks carry Lyme disease?

No — only some blacklegged ticks are infected, and rates vary by region. Other tick species carry different diseases.

### When are ticks most active?

Nymphs peak in May–July; adults in fall. Ticks can be active whenever temperatures exceed roughly 4°C (40°F).

### Where are blacklegged ticks found?

Eastern and midwestern United States and southeastern Canada — deciduous forest and edge habitat from Virginia to Minnesota and into New England.

## Sources

- [IUCN Red List — Ixodes scapularis.](https://www.iucnredlist.org/search?query=Ixodes%20scapularis&searchType=species)
- [Animal Diversity Web — Ixodes scapularis. University of Michigan Museum of Zoology.](https://animaldiversity.org/accounts/Ixodes_scapularis/)

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Source: Global Animal Guide (https://globalanimalguide.org/animals/tick/). Licensed CC BY-NC 4.0 — free for non-commercial reuse with attribution.