Isla del Caño for Anglers

Part of our complete guide: Fishing the Southern Pacific: the complete guide

The short answer

You can't fish at Isla del Caño. The island and a big block of sea around it make up a biological reserve, and Costa Rican law bans commercial, small-scale and sport fishing anywhere inside it. What you can do is fish the water outside the line, which is some of the best inshore and offshore ground on the Osa, and then come back another day (or the same day, with a different plan) to snorkel or dive the reefs.

Boats from Drake Bay and Sierpe run out past the island to troll for wahoo and tuna and to jig the rocky mounds for cubera snapper, amberjack and grouper. Good captains know exactly where the reserve ends. This page explains where that is, what the rules say, who fishes these waters, and how a reserve visit works if you want to see the reefs too. For the whole coast, see our Southern Pacific fishing guide.

The reserve and its line in the water

Isla del Caño sits on the continental shelf about 16 km off the Osa Peninsula, in Costa Rica's far south. A 1976 decree first protected it, and Law 6215 of March 1978 made it a biological reserve, which is the strictest kind of protected area after an absolute reserve. SINAC, the national parks service, runs it through its Osa conservation area. The reserve covers about 320 hectares of land and 5,800 hectares of sea, so most of it is water.

That water is why it's protected. SINAC calls Caño's reefs some of the largest and best kept on the country's Pacific coast, with 5 coral platforms, and the area is a nursery for humpback whales from both hemispheres. On land there are remains of pre-Columbian stone spheres and old forest.

The catch for anglers is that the boundary isn't marked on the water. There are no buoys around the reserve, and from a boat the line is just open sea. Captains who fish here every week carry it in their GPS and their heads. If you're on a boat you've found yourself, ask the captain to show you the boundary on the plotter before lines go in.

What the rules say

SINAC's own page for the reserve sets out the rules plainly. The ones that matter most to anglers:

• No fishing of any kind. Commercial, small-scale and sport fishing are all banned inside the reserve.
• Look after the water. No dumping anything at sea or on land, and no washing boats or changing engine oil inside the reserve.
• Anchoring. Boats may anchor only in the spot 200 meters off the ranger station.
• Crowd limits. No more than 10 people at a time in each snorkel and dive area, and dives and snorkels only in the zones set by the reserve's public-use decree (40700-MINAE).
• The usual park rules. No single-use plastic, alcohol, smoking or fires, no feeding or touching wildlife, and nobody stays overnight.

On top of the reserve's own rules, Costa Rica's fishing law treats fishing inside a national park or biological reserve as one of the most serious offences on the books. Article 153 of Law 8436 sets a fine of 20 to 60 base salaries and takes away the licence. Our fishing rules guide covers the rest of the national law, and our list of no-take zones shows every protected area on the coast and what's allowed in each.

Fishing the water around the island

Here's the good news: the reserve doesn't shut down the area, it feeds it. Fish move in and out of protected water, and the grounds just outside Caño's line are some of the busiest on the Osa.

South of Drake Bay, the coast along Corcovado National Park is protected too, so boats fish outside its waters. Aguila de Osa notes that the open water off that stretch sees little fishing pressure.

Boats that fish near Caño

These are crews whose websites or booking pages we opened in November 2026 and whose trips were reviewed or on offer for 2026. Nobody pays to be listed.

The Southern Pacific guide lists every fishing business in the zone, and our page on Osa and Golfo Dulce fishing lodges compares the lodges. If you'd rather base yourself across the peninsula, see our guide to fishing from Puerto Jiménez.

The illegal fishing problem nearby

Protected water attracts poachers as well as fish. Commercial longlining with live bait is banned within 30 miles of the whole Pacific coast under INCOPESCA's rules (AJDIP/280-2014, amended by AJDIP/252-2023), because those lines catch sailfish. Even so, a monitoring trip by the group Earthrace Conservation in November 2025, reported by Delfino.cr in April 2026, found longliners working inside that band, including a group of boats about 10 nautical miles from Isla del Caño. Every line its crew inspected had some problem, and catches included sailfish and sea turtles.

Sport boats can still use live bait inside the 30 miles; the ban is on commercial longlines. If you see lines and buoys strung across the water near the reserve, tell your captain. Local crews are the ones who report it to the Coast Guard.

Visiting the reserve on a snorkel or dive day

Plenty of anglers spend one day fishing and another in the water at Caño. It's a separate trip, run by tour and dive operators rather than fishing crews, and SINAC's rules are strict:

• Booked and paid ahead. Reservations go through SINAC's Osa reservation office by email, no more than 8 days before the visit. Tour operators and lodges almost always handle it for you.
• Registered guide. Every group goes in with a local guide or certified dive guide registered with the Osa conservation area's sustainable tourism office. Without one, you'll be turned away.
• Hours. 8 am to 3 pm.
• Fees. There's a per-person entry fee, a diving fee and an anchoring fee for the boat. Most tour prices include them.
• Water only. When we checked SINAC's page in November 2026, landing on the beach, ranger station and trails was still closed under a rule that dates from the pandemic, so plan on a day spent in and on the water.
• What to bring. There's no drinking water on the island. Bring water in a reusable bottle, a hat, sunscreen and a dry bag.

Snorkelers float over shallow reef full of fish, often with turtles, rays and white-tip reef sharks. Divers visit deeper rocky pinnacles with schooling jacks and barracuda. Our sister site scuba.cr covers Caño's dive sites in detail, and our guide to snorkeling in Costa Rica compares it with other spots.

When to go

Fish are around Caño all year, and the Osa often has billfish when the rest of the coast goes quiet. Our national fishing seasons guide has the full chart; for these waters it comes down to:

SINAC lists January to April as the drier months, and calmer seas then mean easier crossings. Humpback whales show up at more than one time of year, because both northern and southern populations use the area.

Getting there

Most anglers fishing near Caño stay in Drake Bay or Sierpe.

Domestic planes have tight baggage limits, so check before you pack rod tubes. Our trip planning guide covers licences, packing and timing.