Ascension Bay

Sian Ka'an · Yucatan

Quintana Roo, Mexico

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Target species: Permit, Tarpon, and Bonefish.

About this Water

Ascension Bay on Mexico's Yucatan Peninsula's southeastern coast is among the world's premier saltwater fly fishing destinations — over 200 square miles of flats, mangrove creeks, and lagoon systems supporting bonefish, permit, tarpon, and snook in fishable numbers. The bay's central feature, the Boca Paila lagoon system, is one of the most consistent permit fisheries in the world. Resident tarpon in the 20–60 pound class hold in the channels and creeks year-round. Lodges operate from Punta Allen and inside the Sian Ka'an Biosphere Reserve.

Ascension Bay sits inside the Sian Ka'an Biosphere Reserve — UNESCO World Heritage status — protecting one of the largest contiguous flats systems in the Western Hemisphere from coastal development.

January Outlook

January at Ascension Bay offers world-class permit and bonefish fishing. Cooler temperatures keep fish active all day. Large permit are on the white sand flats. Bonefish schools are enormous in the interior.

Productive Patterns

  • Merkin Crab (tan/brown)
  • Del Brown Permit Fly
  • Crazy Charlie
  • EP Spawning Shrimp

Tips

Ascension Bay permit are regarded as the most challenging in the world. January water clarity is exceptional — fish can see you from 60 feet. Long casts and precise presentations are essential.

Water Notes

Water 74-78°F. Northeast trade winds create some chop. Protected interior bays provide relief on windy days.

February Outlook

February is outstanding for permit with fish very active on the sand flats and reef edges. Bonefish are prolific on the interior flats. Tarpon appear in the creeks and channels — some very large fish.

Productive Patterns

  • Merkin Crab
  • Del Brown
  • Crazy Charlie (bone)
  • Tarpon Toad (backcountry)

Tips

Permit require precise crab presentations. Watch for 'nervous water' and subtle movements of permit approaching the flat. Backcountry tarpon in the mangrove creeks can be 80+ lbs.

Water Notes

Water 76-80°F. Trade winds moderate. The finest permit conditions of the year.

March Outlook

March is the peak month at Ascension Bay. Permit schools are on the flats in good numbers, bonefish are everywhere, and tarpon are migrating through the bay. Grand slams are a genuine possibility.

Productive Patterns

  • Merkin Crab (3/0)
  • Del Brown
  • Tarpon Toad
  • Gotcha (bonefish)

Tips

The grand slam capital of the world. March is when the legendary permit fishing of Ascension Bay is in full swing. Schools of 20+ permit on shallow sand flats. Book years ahead.

Water Notes

Water 78-82°F. Ideal conditions — light trades, clear water, calm mornings.

April Outlook

April is exceptional with all three species in peak form. Large tarpon move through the bay in schools. Permit are accessible and numerous. Bonefish are active on every flat. The quintessential Yucatan grand slam month.

Productive Patterns

  • Tarpon Toad (large)
  • Permit Merkin
  • Gotcha
  • Black Death (tarpon)

Tips

April tarpon at Ascension Bay can be 100+ lbs rolling in the channels. Permit and bone on the interior flats. Grand slam requires an early start and a highly skilled guide.

Water Notes

Water 80-84°F. Calm mornings are the norm. South wind can dirty some exposed flats by afternoon.

May Outlook

May has outstanding fishing but increasing heat. Morning permit and bone are excellent. Summer thunderstorm pattern begins. Tarpon migration is winding down. Get on the water by 6am.

Productive Patterns

  • Merkin Crab
  • Gotcha
  • Bonefish Clouser
  • Spawning Shrimp

Tips

Fish the morning incoming tide aggressively. Permit are less concentrated than spring but still findable. Afternoon storms build from the interior daily.

Water Notes

Water 84-88°F. Rainy season approaching. Morning window is 6am-noon. Afternoons are stormy.

June Outlook

June marks the start of rainy season at Ascension Bay. The permit fishing drops off significantly as fish scatter with the summer rains, but bonefish remain active year-round on the interior flats. The lodges operate with reduced staffing and lower rates. Morning sessions from sunrise to 10am can still produce excellent bonefish action. The interior backcountry lagoons hold snook and juvenile tarpon throughout the summer.

Productive Patterns

  • Gotcha (bonefish)
  • Crazy Charlie (tan)
  • Spawning Shrimp (small)
  • EP Minnow (snook/tarpon)

Tips

June rainy season means afternoon storms daily — sometimes severe. Fish the morning tide hard. Bonefish are still abundant in the interior bays and are feeding actively on the sand. Snook in the mangrove creeks offer a fun alternative when the wind comes up. Some lodges offer significant summer discounts.

Water Notes

Water 86-89°F. Rainy season begins. Afternoon squalls common and sometimes severe. Fish 6-11am window. Permit largely absent until October.

July Outlook

July is low season at Ascension Bay — hot, rainy, and quiet. Lodges are staffed at reduced capacity. That said, bonefish are always present in the bay and the morning fishing can be excellent. The interior flats are calmer than the exposed outer areas, which can be choppy from summer squalls. Some of the largest permit of the year have been caught in July by dedicated permit anglers who know where the resident fish hold.

Productive Patterns

  • Gotcha (small, tan/white)
  • Crazy Charlie (#6)
  • Spawning Shrimp (#8)
  • Glass Minnow (backcountry)

Tips

Committed anglers who visit in July often get undivided guide attention and exceptional value. Fish the incoming morning tide on the interior bonefish flats. Some resident permit hold on specific sand bores year-round — ask your guide about summer permit locations. Return to the lodge by 11am before afternoon storms arrive.

Water Notes

Water 87-90°F. Peak rainy season. Daily afternoon convection. Humid and hot. Low-season rates. Bonefish year-round, permit scarce but possible.

August Outlook

August is the quietest and hottest month at Ascension Bay. Fishing is confined to early morning. The bay's resident bonefish are always available but slower in the warm water. A few committed lodges remain open with skeleton staff. Hurricane risk is elevated but the Yucatan Peninsula sits in a relatively sheltered position. The silver lining is that August visitors often get world-class bonefishing to themselves.

Productive Patterns

  • Gotcha (#6-8)
  • Crazy Charlie (small)
  • Spawning Shrimp (small)
  • Snook Clouser (mangroves)

Tips

An August Ascension Bay trip is for the truly dedicated. The bonefish are there — in good numbers — just slow to bite in 90°F water. Strip slowly. Fish creek mouths on the drop tide where cooler water flows. The snook fishing in the mangrove edges is surprisingly good in summer. Check the hurricane center daily.

Water Notes

Water 88-91°F. Peak summer. Morning-only fishing. Hurricane season — monitor forecasts. Heat index over 100°F midday. Best value rates of the year.

September Outlook

September begins the transition back to fall at Ascension Bay. The second half of September often sees the first frontal influence from the north, cooling the flats slightly and triggering improved fish activity. Early September is still very hot and primarily a morning proposition. By late September, the first permit are starting to reappear on the outer sand bores. Hurricane season remains active through the month.

Productive Patterns

  • Gotcha (tan/pink)
  • Merkin Crab (small, returning permit)
  • Crazy Charlie
  • Spawning Shrimp (#6)

Tips

Target the second half of September if possible — conditions improve noticeably by month end. The first returning permit typically show up on the outer flat edges east of the interior bay. Bonefish fishing improves as water temps drop below 87°F. Watch for the first norther of fall — fish aggressively in the window immediately following frontal passage.

Water Notes

Water 85-88°F slowly cooling. Hurricane season still active. Transitional conditions — improving late in the month. Permit beginning to return to outer flats.

October Outlook

October is an excellent fall month at Ascension Bay. Hurricane season winding down, fish are actively feeding, and permit are beginning to concentrate. Bonefish remain abundant year-round.

Productive Patterns

  • Merkin Crab
  • Gotcha
  • Spawning Shrimp
  • Del Brown

Tips

October permit fishing can rival March. Lodges are less full and prices are often lower. Bonefish are accessible and large (8-12 lbs average).

Water Notes

Water 82-86°F. Hurricane season ends. Conditions improve dramatically through October.

November Outlook

November is outstanding with cooler temperatures and excellent fishing. Permit are on the sand flats, bonefish schools are large, and a few late tarpon are in the channels. One of the finest months to visit.

Productive Patterns

  • Merkin Crab
  • Del Brown Permit Fly
  • Gotcha
  • Crazy Charlie

Tips

November mornings are cool and comfortable. All-day permit fishing is possible in November. Bonefish schools are large and active throughout the day.

Water Notes

Water 78-82°F. Northeast trade winds return. Excellent visibility. Some of the best permit conditions of the year.

December Outlook

December has exceptional permit and bonefish fishing. Holiday visitors find excellent conditions. Large permit schools are accessible. Wind can be an issue later in the month but interior flats provide shelter.

Productive Patterns

  • Merkin Crab
  • Del Brown
  • Crazy Charlie
  • EP Spawning Shrimp

Tips

Fish the protected interior bays on windy days. Permit on the lee side of sand bores. December has some of the largest bonefish of the year in the bay.

Water Notes

Water 76-80°F. Northeast trades build. Interior flats are protected. Christmas/New Year fishing is very good.

Access & Approach

Cancun is the international gateway; transfers to Punta Allen take 2–3 hours. Lodges inside the Sian Ka'an Biosphere offer on-water access. Mexican fishing license required. Guides essential.

About Current

Ascension Bay conditions on Current combine real-time flow data (USGS, WSC, CDEC, CEHQ), weather, tide predictions, hatch probabilities calibrated to this specific water, and recent fly shop reports from the area.

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