Ocean & Marine Life in Manuel Antonio
Most of Manuel Antonio National Park is not forest at all but sea: a blue world of rocky islets, sea fans, schools of reef fish and, for much of the year, humpback whales that travel thousands of kilometers to have their calves here. Dolphins ride the bow waves of boats out of Quepos, pelicans and frigatebirds wheel over the islands, and olive ridley turtles come ashore on the park’s southern beaches.
This guide covers what lives off our coast, when to see it, how to watch it respectfully under Costa Rica’s rules, and how to plan a day on the water.
Manuel Antonio's ocean in brief
| Quick facts | |
|---|---|
| Marine area | About 25,600 hectares of sea against roughly 1,950 of land, with twelve small islands (Visit Costa Rica; SINAC) |
| Whales | Humpbacks from the Northern Hemisphere (about December to April) and the Southern Hemisphere (about July to November); Bryde’s whales also reported |
| Dolphins | Pantropical spotted and bottlenose dolphins reported in the park’s waters; spinner dolphins live farther offshore in Costa Rica’s Pacific |
| Sea turtles | Olive ridleys nest mainly on Playa Savegre, in the park’s southern sector; green and hawksbill turtles nest there occasionally |
| Reef life | 96 fish species from 27 families, about 100 mollusks and 8 coral species recorded in the park’s waters (park management plan) |
| Seabirds | Brown pelicans, magnificent frigatebirds, brown boobies, bridled terns and white ibises use the islets |
| Key rules | Boats keep at least 100 m from whales and 50 m from dolphins; swimming with cetaceans is not allowed (Decree 32495-MINAE) |
A national park that is mostly ocean
When Manuel Antonio National Park was created in 1972, its founding law already included the surrounding waters, and later decrees added the islands (park management plan, SINAC). Today the sea is by far the larger part of the park. Visit Costa Rica lists about 1,953 hectares of land and 25,634 hectares of sea, and the park’s management plan describes the marine portion as “considerably larger” than the land, yet the least studied.
What has been studied is impressive. The plan records 12 islets, around 100 species of mollusks, 96 species of fish from 27 families, 25 crustaceans, 8 echinoderms (sea stars, sea urchins and sea cucumbers) and 8 species of coral. In the open water, researchers have reported humpback whales, Bryde’s whales, bottlenose dolphins and pantropical spotted dolphins, along with areas used by false killer whales.
Most of the park’s sea lies between 30 and 200 meters deep, with a narrow shallow band close to the coast. That shallow band, the rocky points and the islands are where snorkelers and divers spend their time. Farther out, the deeper blue is the realm of whales, dolphins and the big game fish that make Quepos famous for sport fishing.
The land and sea work as one system. The same plan notes that soil washed down from surrounding farmland settles on the park’s coral, which is one reason the forest corridors around Manuel Antonio matter for the ocean too. Our plants and rainforest guide explains the forest side of the story, and the national park guide covers tickets, trails and the beaches inside the park.
Humpback whales: visitors from north and south
Few places on Earth receive humpback whales from both hemispheres, and Costa Rica’s Pacific coast is one of them. That is why the whale season here is so long.
The northern whales (about December to April)
Humpbacks of the Central America population spend the northern summer feeding off California, Oregon and Washington, then travel south to breed and give birth off Central America, including Costa Rica (NOAA Fisheries). This population is listed as endangered under the United States Endangered Species Act, so every calf born in these warm waters counts.
The southern whales (about July to November)
The second group feeds in the cold waters off the Antarctic Peninsula during the southern summer. A study published in Biology Letters (Rasmussen and colleagues, 2007) followed whales, including a mother and calf, from Antarctica to Central America: a journey of roughly 8,300 km, then the longest migration documented for any mammal. They reach Costa Rica during our rainy season, which is why the green months are also whale months.
A long-term analysis of sightings off Costa Rica found two peaks, February to April and August to September, matching the two populations (Pelayo-González and colleagues, 2026, Ecology and Evolution). An earlier coastal study published in Revista de Biología Tropical confirmed that both populations use Costa Rican waters, with northern whales seen between December and March.
What you may see
Mothers resting at the surface with a calf at their side, the slow arch of a back, a tail lifted before a dive and, with luck, a full breach. Males sing on the breeding grounds, and some boats carry a hydrophone so you can listen. Watch for the blow first: on a calm morning a humpback’s spout can be seen from far away.
Marino Ballena National Park
Farther south along the coast, near Uvita, Marino Ballena National Park was created in 1989 and, according to SINAC, was the first protected area in Costa Rica created specifically for its marine resources. Its famous “whale’s tail”, a sandbar and rock formation at Punta Uvita, is best seen at low tide. Uvita also hosts a yearly Whale and Dolphin Festival; its fifteenth edition was held in early September 2025 (Tico Times). It makes a lovely day trip, and our waterfalls and day trips guide has more ideas for the road south.
Planning your stay around whale season? Book a whale-watching boat trip with our concierge and we will match it to the best days of your visit.
Dolphins, Bryde's whales and other ocean wanderers
Whales come and go with the seasons; dolphins can be found here year-round. Twenty-nine species of whales and dolphins have been recorded in Costa Rican waters (Revista de Biología Tropical), and the waters off Quepos and Manuel Antonio host several of them.
Pantropical spotted dolphin (Stenella attenuata)
The dolphin you are most likely to meet. In a year-long study on Costa Rica’s Pacific coast, spotted dolphins made up 68 percent of all cetacean sightings, far ahead of humpbacks at 13 percent and bottlenose dolphins at 10 percent (Martínez-Fernández, Montero-Cordero and May-Collado, Revista de Biología Tropical, 2011). Scientists describe a coastal form of this species that lives close to shore along Central America. Adults are freckled with pale spots, and calves are born plain grey and gain their spots with age. They often travel in lively groups and love to ride a boat’s bow wave.
Common bottlenose dolphin (Tursiops truncatus)
Larger, sturdier and plain grey, with a short, thick beak. The park’s management plan lists bottlenose dolphins among the cetaceans reported in its waters, and they are one of the species scientists consider most linked to the coast in Costa Rica’s Pacific.
Spinner dolphin (Stenella longirostris)
Famous for leaping and spinning on its long axis. The spinners of the eastern tropical Pacific, including the Central American spinner, live only in this part of the ocean (NOAA). They are mainly an open-ocean species, so they are a special bonus on trips that head farther offshore rather than a regular sight near the beaches.
Bryde’s whale and false killer whale
The park’s management plan also reports the Bryde’s whale (Balaenoptera edeni), a sleek tropical baleen whale that, unlike the humpback, stays in warm waters all year, and notes important areas used by false killer whales (Pseudorca crassidens). Killer whales are rare visitors, but researchers have documented sightings in the Central Pacific over the decades (Revista Ciencias Marinas y Costeras, Universidad Nacional).
No guide can promise a particular species, and good captains will tell you so. Sightings depend on the sea, the season and the day. Our concierge works with local operators who know these waters well: request a dolphin and whale trip or ask us which outing suits your dates.
Sea turtles of the Central Pacific
Sea turtles have been part of this coast for a very long time. Inside the national park, by Playa Manuel Antonio, SINAC describes a circle of stones that, by local account, Indigenous people once used as a trap for turtles and fish. Today the turtles are protected, and the park’s southern sector is an important nesting area.
Olive ridley (Lepidochelys olivacea)
The olive ridley, called tortuga lora in Costa Rica, is the turtle that nests most often in the park. According to the management plan, nesting happens mainly on Playa Savegre, in the El Rey sector, a long, wild beach of about 13.5 km that makes up most of the park’s shoreline. Monitoring there has run through the rainy months, from about June or July to December, and counted hundreds of nesting visits a season: 248 in 2004, 324 in 2005 and 491 in 2007. The olive ridley is listed as Vulnerable on the IUCN Red List.
Olive ridleys are small as sea turtles go, with a heart-shaped, olive-grey shell. Females haul themselves up the beach, dig a nest with their back flippers, lay their eggs and return to the sea. The hatchlings emerge weeks later and race for the waves.
Green and hawksbill turtles
The same plan notes that green turtles (Chelonia mydas) and hawksbills (Eretmochelys imbricata) nest occasionally on the park’s beaches. At sea, any turtle you spot from a boat is worth a quiet moment: they come up to breathe, take a look around and slip back down.
Watching turtles well
- Let nesting females and hatchlings move on their own. Give them space and keep out of their path to the sea.
- Keep the beach dark. Bright lights and camera flashes confuse turtles, so leave the photos to the moonlight.
- Join a guided, permitted outing rather than searching the beach alone; local projects and guides know the rules for each beach.
- From a boat, enjoy the moment from a distance and let the turtle choose its course.
Turtle activity depends on the season and the night. Ask our concierge about responsible turtle-watching options during your dates.
Snorkeling, coral and reef fish
Manuel Antonio’s underwater world is a rocky reef rather than a classic coral wall, and that is part of its charm. Scientists note that coral formations are naturally scarce in Costa Rica’s Central Pacific; instead, the sea floor holds isolated coral colonies and small coral communities growing on rocks along the coast (park management plan, citing Cortés and colleagues). Seven coral species have been recorded in these colonies, among them Pavona, Pocillopora and Porites corals and the orange cup coral Tubastraea coccinea. Around Olocuita and Toro Amarillo islands, purple and orange sea fans (gorgonians of the genus Pacifigorgia) are abundant.
The fish steal the show. A rapid ecological survey in 2012 counted 86 fish species from 27 families around the islets, with damselfish, grunts, wrasses, snappers and groupers the richest groups (park management plan). Divers at the islets have recorded spotted eagle rays, giant mantas and whitetip reef sharks, and on the rocks you may find octopus, sea slugs, chitons and sea stars.
Where to snorkel
- Playa Manuel Antonio, inside the park. SINAC points to the rocky sides of this sheltered bay for fish and some coral. Bring a mask; it is the easiest snorkel in the area. The park is open Wednesday to Monday, so see our park guide for tickets.
- The islets by boat. The park’s management plan sets aside areas for snorkeling and scuba diving around Isla Larga (Mogote) and Isla Olocuita. Boat trips from Quepos reach these and other spots, and a dive shop in Quepos was reported to offer 19 dive sites, several within the park.
A field guide to what you may see
| Look for | What it looks like | Where |
|---|---|---|
| Panamic sergeant major (Abudefduf troschelii) | Small, yellowish with bold black vertical bars; often in groups | Rocky shallows, Playa Manuel Antonio |
| Damselfish (Stegastes) and petacas | Small, territorial fish that guard patches of rock and algae | Rocks close to shore |
| Wrasses (señoritas, Halichoeres) | Slim, colorful fish that dart over the rocks | Rocky points and islets |
| Parrotfish (Scarus) | Large scales, beak-like teeth; you may hear them crunch algae | Islets and rocky reefs |
| Surgeonfish (Prionurus) | Grey-brown bodies with bright yellow or dark tail spots | Islets, in schools |
| Threebanded butterflyfish (Chaetodon humeralis) | Flat, silvery with dark bands | Rocky reefs |
| Snappers and grunts (Lutjanus, Haemulon) | Schools hanging in the water near rocks | Islets |
| Sea stars and sea urchins | Pharia and Phataria sea stars; long-spined Diadema urchins | Sandy-rocky bottoms (look, don’t touch) |
Species from the park management plan (ONCA 2012 survey). Visibility changes with tides, swell and rain runoff, so your operator will choose the best spot on the day. Our blog post on snorkeling in Manuel Antonio has more tips, and our concierge can book a snorkeling trip for you.
Snorkel kindly
- Float, look and keep your fins off the coral and rocks; even a light touch damages living tissue.
- Leave shells, coral and creatures where they are. SINAC asks visitors not to collect shells or snails.
- Choose a mineral sunscreen and a rash guard, which also keeps you comfortable in the sun.
- Never feed fish; it changes their behavior just as it does for monkeys.
The park's islets and their seabirds
Look out from Punta Catedral or from any terrace on the Manuel Antonio hillside and you will see them: a scatter of rocky islands, some bare, some crowned with scrubby trees, white with the work of seabirds. The national park protects twelve of these islets. Most have little vegetation, but they are vital places for seabirds to rest, feed and raise their young, and Olocuita and Toro Amarillo are the most used for nesting (park management plan, citing Alvarado 2004).
Who lives on the islets
- Brown pelican (Pelecanus occidentalis). Lines of pelicans gliding low over the waves are one of the classic sights of the Manuel Antonio coast. Watch them fold their wings and plunge for fish.
- Magnificent frigatebird (Fregata magnificens). Called tijereta for its long, scissor-like tail, it hangs almost motionless in the wind on huge, angular wings. Frigatebirds cannot settle on the water to fish, so they snatch prey from the surface or chase other birds for their catch.
- Brown booby (Sula leucogaster). Dark brown above with a clean white belly; it dives for fish like a dart.
- Bridled tern (Onychoprion anaethetus). A slender, elegant tern of tropical seas.
- White ibis (Eudocimus albus). White with a curved red-pink bill, often seen moving between the islands and the mangroves.
Lobsters, oysters and the large conch known locally as cambute are abundant around the islets, and the sea fans of Olocuita and Toro Amarillo make the area a favorite of divers.
The islands are best enjoyed from the water or from the viewpoints, so the birds can nest in peace. A boat trip gives you the closest respectful look, and binoculars make all the difference. Our birds of Manuel Antonio guide and the birdwatching blog post cover the forest birds you can add on the same day, and many of them, toucans and scarlet macaws included, often visit the gardens at ECOTICA.
Costa Rica's rules for whale and dolphin watching
Costa Rica takes its whales seriously. A national decree declares the country’s interior waters, territorial sea and Exclusive Economic Zone a sanctuary for whales and dolphins (Decree 34327-MINAE-MAG), and since 2005 a dedicated regulation, Executive Decree 32495-MINAE, has set out how boats must behave around cetaceans. Good operators follow these rules as second nature, and knowing them helps you choose a responsible tour.
The main points of the regulation
- Distance. Boats keep at least 100 meters from whales and at least 50 meters from dolphins.
- Approach. Boats approach slowly, from behind and to the side at an angle, moving parallel to the animals rather than cutting across their path or heading straight at them.
- Time. Each observation should last no more than 30 minutes, so the animals can rest, feed and nurse in peace.
- In the water. Swimming or diving with whales and dolphins is not allowed. Enjoy them from the boat.
- Hands off. Touching, feeding or catching cetaceans is prohibited.
Rules as summarized by the International Whaling Commission’s Whale Watching Handbook and Costa Rican sources on Decree 32495-MINAE. If an animal chooses to approach the boat, a good captain slows down or stops and lets it pass.
How to spot a responsible operator
- The captain explains the rules before you set out and keeps to them, even when other boats crowd in.
- The boat slows well before reaching the animals and leaves them calmly.
- Guides talk about behavior and conservation, not only about getting closer.
- Nobody promises a guaranteed sighting or a swim with dolphins.
These same values guide all our responsible wildlife watching advice. When you book your boat trip through ECOTICA, we choose operators who share them.
Boat trips and snorkeling: practical tips
A morning on the Pacific is the other half of a Manuel Antonio stay. Most boat outings leave from Quepos, a short drive from the hotels on the hill, and combine coastline views of the national park, the islets, a snorkel stop and time looking for dolphins and, in season, whales. Mangrove trips through the Damas Island estuary are a calm alternative, timed to the tides; our things to do guide describes them.
Choosing your outing
- Whale and dolphin trips focus on finding cetaceans and usually travel farther along the coast.
- Snorkel and coastline trips spend more time at the islets and rocky bays.
- Sunset sails are about the light, the coast and a drink on deck; dolphins are a frequent welcome bonus.
- Kayak outings along the shore or the mangroves bring you close to the water at your own pace.
What to bring
- Mineral sunscreen, a hat that stays on in the wind, and a long-sleeved shirt or rash guard.
- Polarized sunglasses, which cut the glare and make spouts, fins and fish easier to see.
- A zoom lens or binoculars, and a dry bag for your phone.
- Seasickness remedies if you are prone to it; take them as directed before you board.
- A light layer for the ride home and a towel for after snorkeling.
Good to know
- The national park is closed on Tuesdays, which makes Tuesday a natural ocean day. See our sample itineraries.
- In the green season, rain on Costa Rica’s Pacific side tends to fall in the afternoon (IMN), so morning departures fit the weather nicely, and this is also the season of the southern humpbacks.
- Sea conditions change from day to day; your captain makes the call on routes and snorkel stops.
- Wear the life jacket provided and follow crew instructions when moving around the boat.
Planning this ahead of time? Book it with our concierge or ask us for details, and browse our ocean and boat tours. Back on land, the wildlife carries on: howler monkeys, white-faced capuchins, squirrel monkeys, sloths, toucans and scarlet macaws are often seen right on ECOTICA’s 10-acre rainforest grounds, sometimes from your own porch. An afternoon at Jungle Spa and a cocktail at La POZA round off a salt-water day beautifully.
What's in season on Manuel Antonio's coast
There is no wrong month to go to sea here, only different highlights. Use this table to match your dates to the ocean’s calendar. Seasons are approximate: whales keep their own schedule, and peaks shift a little from year to year.
| Months | Season (IMN) | In the water |
|---|---|---|
| December to March | Dry season | Northern humpbacks arrive; dolphins year-round; calm, sunny days for snorkeling and sunset sails |
| February to April | Late dry season and April transition | Peak of northern humpback sightings (Pelayo-González et al., 2026) |
| May and June | Start of the rainy season | Dolphins year-round; quieter waters between whale seasons; olive ridley nesting season beginning on the park’s southern beaches |
| July to November | Rainy season (September and October the wettest) | Southern humpbacks from Antarctica, peaking August to September; olive ridley nesting at Playa Savegre through about December; Whale and Dolphin Festival in Uvita (early September in 2025) |
| Year-round | Pantropical spotted and bottlenose dolphins, reef fish at the islets, pelicans and frigatebirds over the coast |
For weather, crowds and what each month feels like on land, read our seasonal guide to the best time to visit Manuel Antonio. If your heart is set on whales, tell us when you are coming and we will help you choose dates for your stay that line up with the season.
Marine life in Manuel Antonio: questions and answers
When is whale season in Manuel Antonio?
Humpbacks visit Costa Rica’s Pacific coast in two seasons: Northern Hemisphere whales from about December to April and Southern Hemisphere whales from about July to November. Long-term sightings peak in February to April and August to September.
Can I see dolphins all year?
Yes, dolphins live in these waters year-round. Pantropical spotted dolphins are the most frequently seen on Costa Rica’s Pacific coast, followed by bottlenose dolphins, though no trip can guarantee a sighting.
Can I swim with dolphins or whales in Costa Rica?
No. Costa Rica’s Decree 32495-MINAE prohibits swimming or diving with cetaceans, and boats must stay at least 100 m from whales and 50 m from dolphins. Watching from the boat is the respectful way, and often the best view.
Where is the best snorkeling near Manuel Antonio?
The rocky sides of Playa Manuel Antonio inside the national park are the easiest spot from shore, and boat trips reach the islets, where the park sets aside snorkeling areas around Isla Larga and Isla Olocuita. See our snorkeling guide.
Is there coral in Manuel Antonio?
Yes, though it grows as scattered colonies on rocks rather than large reefs, which is natural for the Central Pacific. Eight coral species are recorded in the park, and sea fans are abundant around Olocuita and Toro Amarillo islands.
Do sea turtles nest near Manuel Antonio?
Yes. Olive ridley turtles nest mainly on Playa Savegre, in the national park’s southern El Rey sector, with monitoring there running from about June or July to December. Green and hawksbill turtles nest there occasionally.
Is Marino Ballena National Park worth the trip from Manuel Antonio?
For whale lovers, yes. It lies farther south near Uvita, was created in 1989 for its marine resources, and its whale’s tail sandbar is a beautiful sight at low tide. Our day trips guide has ideas to combine on the way.
What seabirds can I see from Manuel Antonio?
Brown pelicans, magnificent frigatebirds, brown boobies, bridled terns and white ibises use the park’s twelve islets, with Olocuita and Toro Amarillo the main nesting islands. A boat trip or the park’s viewpoints give the best looks.
Can ECOTICA book a whale-watching or snorkeling trip for me?
Yes. Our concierge books boat trips, snorkeling and other ocean outings with local operators. Send your dates through the tours form and we will suggest the best option for the season.
Keep exploring
Keep exploring the wild side of Manuel Antonio: start with our wildlife overview, meet the three monkeys and the sloths, discover frogs, butterflies and the forest at night, compare the best beaches, and plan the rest of your days with our itineraries. When you are ready, check dates and rates at ECOTICA.
Found an animal that needs help? Here is exactly what to do and who to call. For people, our health and safety guide keeps emergency numbers close at hand.
Arrive with everything ready
Tell us your dates and we will have the best of Manuel Antonio waiting for you before you land:
- Book your tours: Manuel Antonio National Park with a naturalist guide, boat trips, zip lines, rafting and more
- Reserve Jungle Spa: massages, couples treatments, facials and body rituals
- Airport transportation: a private transfer from San José, US$195 each way for up to 5 people
- Concierge requests: dinners, celebrations and anything special
- Stay at ECOTICA: check dates and rates for our bungalows and suites
Where our facts come from
- SINAC – Plan General de Manejo, Parque Nacional Manuel Antonio 2013–2018 (PDF; marine species, islets, turtles, coral, zoning)
- NOAA Fisheries – Humpback whale (Central America distinct population segment)
- Rasmussen et al. (2007) – Southern Hemisphere humpback whales wintering off Central America, Biology Letters
- Martínez-Fernández, Montero-Cordero & May-Collado (2011) – Cetáceos de las aguas costeras del Pacífico norte y sur de Costa Rica, Revista de Biología Tropical
- SINAC – Parque Nacional Marino Ballena (official page)
Photos: Jan Jüttner, Ben Phillips, Jonathan Reynaga, Lachlan Ross, Koen Swiers, Landiva Weber, Kristina Schultheiß / Pexels.
