Whether you are ranching in South Texas or hiking the Hill Country, here is what is on the move right now.
1. New World Screwworm: "This Is Not a Drill."
The most critical alert for April 2026 involves the New World Screwworm (NWS). On April 20, 2026, Texas Agriculture Commissioner Sid Miller sounded the alarm following a confirmed case in a calf in Nuevo León, Mexico—just 62 miles from the Texas border.
- The Threat: NWS is a flesh-eating parasite. The adult flies lay eggs in the open wounds of warm-blooded animals (including livestock, pets, and humans). These eggs hatch into maggots that feed on living tissue, "screwing" deep into the flesh.
- The Response: The USDA has shifted sterile fly dispersal operations to include a 50-mile zone inside the Texas border. These sterile flies mate with wild flies, producing non-viable eggs that break the life cycle.
- Action Plan: Monitor animals daily for wounds as small as a tick bite or navels of newborns. If you see unusual maggots or a wound that won't heal, do not move the animal. Contact the Texas Animal Health Commission (TAHC) or your vet immediately at 1-800-550-8242.
2. Invasive Fruit Fly Quarantines: Rio Grande Valley
The USDA and the Texas Department of Agriculture (TDA) have established multiple emergency quarantines this spring to protect the state's multi-million-dollar citrus industry.
Sapote and Mexican Fruit Fly Quarantines
- Active Zones: As of April 6, 2026, new quarantines are in effect for Cameron, Hidalgo, and Zapata counties. Specifically, zones in Rio Hondo, Harlingen, Alamo, and Zapata have been placed under lockdown.
- The Danger: These flies lay eggs in citrus and other fruits; the larvae then destroy the fruit from the inside out.
- The Rule: If you live in a quarantine zone, do not move homegrown fruit off your property. This includes oranges, grapefruit, and mangoes. Consolidate fallen fruit into double-lined plastic bags and dispose of it in the trash, not in the compost.
3. Venomous Snakes: The "Spring Peak."
As temperatures consistently hit the 80s and 90s this April, Texas's venomous snakes are fully active. Wildlife experts are noting a spike in "garage and patio" encounters as snakes seek shade and water.
- The Species: Western Diamondback Rattlesnakes and Copperheads are the primary concerns. Copperheads, in particular, are experts at blending into the mulch and leaf litter of suburban flower beds.
- The "Water" Warning: In drier parts of the state, snakes are drawn closer to homes by moisture from garden hoses and air-conditioning drip lines.
- Safety Tip: Always wear closed-toe shoes when walking outdoors at night. Most bites occur when a person accidentally steps on a snake they didn't see.
4. Biting Insects and "Poppy Seed" Ticks
Despite the dry weather in some regions, the 2026 biting insect season has arrived with a vengeance.
- The Nymph Surge: April marks the emergence of nymphal ticks. These are the size of a poppy seed and are responsible for the majority of Lyme disease and Alpha-gal syndrome (red meat allergy) cases because they go undetected for so long.
- Mosquito Management: In North and Central Texas, mosquito control districts began aerial larvicide treatments (using drones) during the week of April 13, 2026.
- Prevention: Wear long sleeves and use EPA-registered repellents like DEET or Picaridin. Check your pets for "freckles" that might actually be nymphal ticks after every walk.
5. Fire Ant "Flight" Season
With the spring rains that have hit parts of the state, April is the peak for Red Imported Fire Ants to begin their "nuptial flights."
- The Hazard: This is when winged "reproductive" ants leave the nest to start new colonies. You may see massive swarms on warm, humid afternoons.
- The Action: While the 2026 state-wide quarantine remains in effect for most of Texas, homeowners should use this window to apply "bait-style" treatments. These are most effective right now because the ants are actively foraging to support their new colonies.
Checklist for Texas Residents
- Inspect Every Wound: Check livestock and pets for maggots to prevent a Screwworm outbreak.
- Respect the Quarantine: If you're in the Rio Grande Valley, keep your homegrown citrus at home.
- Snake-Proof Your Yard: Keep grass short and remove brush piles where rattlesnakes hide.
- Tick Hygiene: Perform a full-body scan every night; the 2026 nymphal infection rate is trending high.
Have you noticed any unusual insect activity in your yard lately? Stay safe out there!