West Indian Fruit Fly Quarantine: Port Isabel, TX

Key facts
Event date	2026-10-07 (federal quarantine; Texas state quarantine established 2026-08-21)
Source published	October 7, 2026
Where it applies	Port Isabel, Cameron County, Texas (19.19 square miles; no commercial agriculture inside)
What to do	Action needed if you live inside the Port Isabel quarantine area and grow host fruit such as mango, citrus or peach: do not move or share it without TDA approval. Nearby residents should check the TDA map. No action needed elsewhere.

If you grow mango, citrus, peach or other host fruit in Port Isabel, Texas, check whether your address is inside the West Indian fruit fly quarantine before you move or share any of that fruit. On October 7, 2026, USDA's Animal and Plant Health Inspection Service (APHIS) set up a 19.19-square-mile federal quarantine there after it confirmed a mated female fly in a trap placed in a mango tree on a residential property (APHIS). The federal order parallels a Texas Department of Agriculture (TDA) quarantine in place since August 21, 2026 (TDA).

Key facts

Dates: Texas quarantine established August 21, 2026; federal quarantine October 7, 2026
Source: APHIS notice DA-2026-45, October 7, 2026
Where: Port Isabel, Cameron County, Texas; 19.19 square miles, with no commercial agriculture inside
What's restricted: moving regulated host fruit out of the area to other states (federal), and moving or distributing it within or out of the area without a permit or compliance agreement (Texas)
Response: APHIS and TDA are carrying out survey, treatment and regulatory work to eradicate the population

Why one fly triggers a quarantine

The West Indian fruit fly (Anastrepha obliqua) is established in Mexico, Central and South America, Puerto Rico and the U.S. Virgin Islands, but not in the continental United States. Females lay eggs in the fruit, and the larvae tunnel through the flesh, making it unfit to eat. APHIS says the species attacks more than 70 plant species (APHIS DA-2026-46). APHIS describes the Port Isabel flies as a transient population that it and TDA aim to eradicate, and a quarantine stops infested fruit from carrying the pest elsewhere in the meantime (APHIS).

Which fruit counts as a host

On the same day, APHIS issued a new federal host list for this fly (APHIS). It covers the berries, fruits, nuts and vegetables of every listed species, including all cultivars, varieties and hybrids. Hosts that home gardeners in South Texas often grow include mango, sweet and sour oranges, tangelo, grapefruit and pomelo, lemons (including Meyer lemon), peach and nectarine, guava, loquat, avocado and starfruit. The full list is attached to the federal order, and TDA links its own regulated host list from its West Indian fruit fly page.

Context: quarantines like this can end

Earlier in 2026, Texas and APHIS quarantined 68.2 square miles around Palmview in Hidalgo County after four West Indian fruit fly larvae were found in grapefruit on a residential property in Mission (APHIS). TDA set that quarantine on January 13, and it was lifted on June 9, 2026, after the population was eradicated (APHIS; TDA). Under Texas rules, a fruit fly is treated as eradicated from an area once a set period passes with no further detections, calculated with a degree-day model (4 TAC §19.154). No end date has been announced for the Port Isabel quarantine.

What to do

Check your address. TDA's West Indian fruit fly page has a map and legal description of the boundary, plus an interactive map where you can enter your address.
Inside the area, keep host fruit where it grew. Texas rules say regulated articles may not be moved within or out of a quarantined area, or distributed within it, except under a permit or compliance agreement from TDA or USDA (4 TAC §19.153). That includes giving fruit to neighbours or taking it to friends outside the area. The full state rules are in Texas Administrative Code Title 4, Chapter 19, Subchapter O (§§19.150–19.154). TDA takes questions at 1-800-835-5832 (1-800-TELL-TDA).
Look at your fruit. If you find maggots inside mangoes, citrus or other host fruit from inside the area, don't move or share it. Call TDA on the same number and ask how to handle it.
Outside the area: no action is needed. APHIS's exotic fruit flies page links to maps and descriptions of current federal fruit fly quarantines.

Why this matters for your garden

Both of this year's West Indian fruit fly detections in Texas came from residential properties, a trap in a backyard mango tree and grapefruit from a home garden, not from commercial groves. That makes home fruit growers in quarantined areas an important part of keeping the pest contained. For routine care, see our guides on when to fertilize mango trees and how to fertilize citrus trees.

West Indian Fruit Fly Quarantine in Port Isabel, Texas: What Home Fruit Growers Should Know