# Invasive sheep threaten native species in Texas

Aoudads introduced after WWII are spreading diseases to local bighorn sheep.

- **Source:** [Popular Science](https://brifing.si/source/cc3d313a-759c-4802-b881-fc8585f35ef9)
- **Published:** 2026-07-13
- **Topic:** [Business](https://brifing.si/c/business)
- **Original article:** <https://www.popsci.com/environment/invasive-texas-sheep-making-bighorns-sick/>
- **On Brifing:** https://brifing.si/s/8f33c948-abca-4eed-90d0-b0884117b31d

## The danger of invasive species

Aoudad sheep, introduced to Texas after WWII, are spreading respiratory diseases to native bighorn sheep. This significantly reduces the survival chances of bighorns.

## Spread of the disease

Aoudads carry bacteria like Mycoplasma ovipneumoniae, threatening both wild and commercial livestock. These pathogens cause high mortality rates among bighorns.

## Historical origins

Aoudads were brought to Texas by soldiers returning from North Africa. Initially bred for hunting, their population has since exploded.

## Ecological impacts

The rapid increase in aoudad numbers is putting pressure on local vegetation. This depletes food sources for bighorns, further reducing their population.

## Research findings

Studies show that aoudads carry pathogens for extended periods without showing symptoms. In contrast, bighorns are far more vulnerable to the disease.

## Conservation efforts

Texas authorities are taking measures to protect bighorns. For example, uninfected individuals are being relocated to safer areas. These efforts are crucial for the species' survival.

## Sources covering this story

- https://www.popsci.com/environment/invasive-texas-sheep-making-bighorns-sick/ — 

---

_Summary written by Brifing from the original reporting. Copyright in the original article belongs to its publisher; read the full piece at the link above._