Wildlife Guide: Whale Shark
Did You Know?
Whale Shark: Fun Facts
1. Big Fish! The whale shark was named for its size - they are actually the biggest fish on the planet.
2. Shark Teeth: Whale sharks have 3,000 tiny teeth arranged into 300 (or more) rows – but they are NOT used for biting or chewing.
3. Wide Mouth: A whale shark’s mouth can be nearly 5 feet wide! But don’t worry; he will not use it to eat you. Whale sharks prefer tiny krill and plankton to people.
4. Spot a whale shark: The spot patterns above their pectoral fins are specific to each individual. Researchers use spot pattern photographs to identify and track them.
In Spanish it is known as “pez dama” which means, “fish lady”. In Taiwan, it is nicknamed “tofu shark” because of the taste and texture of its meat - an indicator of why conservation may be a problem there. See below: “Conservation” for more on whale sharks and Taiwan.
Genus and Species
Subspecies of Whale Shark
There are no known Rhincodon typus subspecies.
Closest Living Relative
Zebra Shark (Stegostoma fasciatum)
Other Related Species
The whale shark belongs to the order: Orectolobiformes or carpet sharks. The following sharks are also in this order: Tasseled wobbegong shark (Eucrossorhinus dasypogon), white–spotted bamboo shark (Chiloscyllium plagiosum), nurse shark (Ginglymostoma cirratum), blind shark (Brachaelurus waddi), and collared carpetshark (Parascyllim collarae).
By The Numbers
IUCN Red List: Vulnerable and Decreasing (2005).
How Many Whales Sharks Are left in the Wild?
The global population number for the whale shark is unknown. However, based on anecdotal evidence and reports from researchers at points along traditional whale shark migration routes, sightings have decreased at some locations. It is not known whether this is due to an overall decline in their population, or due to alterations in migratory patterns, possibly caused by ocean temperature changes that affect their food sources.
Our understanding of whale sharks is very limited, but a number of independent studies on-going around the world are adding to our knowledge base. What is certain is that collisions with boats, habitat degradation and even irresponsible tourism (touching and chasing) can drive whale sharks away from vital feeding (and possibly breeding) grounds. Sound pollution, from increased water traffic both commercial and private, adds to this problem.
Ocean Warming: Global warming is a major issue posing multi-layered concerns for marine scientists. As the oceans warm, it is causing oxygen levels in the water to drop, negatively impacting marine life and changing behavioral patterns. Species that depend on very deep ocean dives for food are staying closer to the surface. Whale sharks are known to make these very deep dives.
Additionally, fish spawning patterns, krill levels, and the formation of plankton plumes, all of which the whale shark depends on for food, are affected by temperature changes. Each of these issues are contributing to changes in whale shark migration patterns and possibly negatively impacting population numbers.
Over Fishing: The problem of overfishing, is two-pronged. First, there is specific whale shark fishing. Their meat, oil, and fins were once highly sought after throughout Asia; global conservation pressure, combined with local education and economic realignment has decreased the demand for whale shark meat and parts to where it now remains centered, albeit mostly underground, in the Taiwanese market.
General commercial overfishing is a more complicated issue. Commercial overfishing in all of the world’s oceans is upsetting marine eco-systems and is a cause of coral reef decline. Marine mega-fauna, including the whale shark, as well as other marine life depend on the coral reefs. As reefs deteriorate so do marine life populations. The direct link between whale sharks and coral reefs was first studied at Ningaloo Reef, Australia in 1996.
Over the last decade, the whale shark's enormous size couple with its gentle demeanor has made swimming with these giants a hugely popular tourist event. Visitor dollars are building marine tourism industries where once whales sharks were actively hunted - and over hunted.
Science & Adventure: Additionally, whale shark research data is being accumulated faster and better than ever before. New research has helped lead to legal protection for the species in Australia, the Maldives, the Philippines, India, Mexico, Honduras, Thailand, Malaysia, Belize and the United States. Citizen Science, in the form of studies that encourage sport divers and other marine tourists to help gather data, is adding real information to our knowledge of whale sharks.
Programs like Wildme and its Wildbook for Whale Sharks photo identification library give an added and important dimension to a fun activity. Instead of just a Facebook post, a vacationer's images of whale sharks can become part of a world wide database used to identify and track the shark's migration, life cycle, and habitat. Greater understanding, plus added government protection, in conjunction with responsible tourism practices are creating a win for the whale shark, local communities on their routes, visitors, and the planet.
More Whale Shark Volunteer Opportunities: Some of the best marine life spots in the world also host non-government research facilities and community out-reach initiatives. Many offer interested laymen from around the world the possibility to spend some time assisting with local programs.
ECOCEAN at Ningaloo, is one of the longest (since 1994) continuously running whale shark studies on the planet. It was here that biologist and project leader, Brad Norman, and information architect, Jason Holmberg, developed the idea, procedure and software that would become the Wildlife Book for Whale Sharks. Researchers at ECOCEAN have identified over 800 whale shark individuals at Ningaloo and discovered that every year 2/3 of these sited are returning from a previous year - some are so familiar that, like old friends, they now have unofficial names.
The Maldives Whale Shark Research Program (MWSRP) encourages volunteers from around the world to come to visit and assist in data collection including photographing, identifying, and measuring whales sharks. Volunteers also participate in local educational programs and beach cleanups.
The Utile Whale Shark Research Project, located at the Deep Blue Resort on Utile Island, Honduras, also utilizes citizen science actively encouraging visitor participation in the Wildbook For Whale Shark program. They are one of the few viewing sites that allow scuba as well as snorkeling with whale sharks.
Donsol Bay, Philippines and Isle of Mujeres, Mexico were formerly subsistence fishing / whale shark hunting communities, but both have turned to responsible marine tourism based economies instead. At Donsol Bay the World Wildlife Fund stepped in and continues to help guide the community with innovative wildlife tourism initiatives. While at Isla Mujeres, Ceviche Tours, co-owned by an islander and a onetime tourist, is one of the leading local commercial businesses that combines neighborhood involvement, responsible marine wildlife experiences, and citizen science to preserve their nature and enhance community well being.
On December 24, 2013, the whale shark was included in Kenya’s new Wildlife Bill, which garnered the species protection in Kenyan waters. In Tanzania, Sea Sense, a marine conservation organization that engages local people as conservation ambassadors and data collectors, has implemented an education workshop for fishermen on Mafia Island where, off the island’s west coast, a small population of whale sharks congregate every year between October and April. The workshop involves promoting whale shark conservation and fishing practices that are sustainable and non-stressful to other marine life including whale sharks. Sea Sense has also established programs in local Mafia Island schools that teach students about the importance of the whale shark in their waters.
Adult Weight: 20 tons or 44,092 pounds ( 20,000k) and more.
Adult Length: 40 feet (12m). Whale sharks have been reported up to 60 feet (18m)
The whale shark is both the largest shark species and the largest fish species alive today. Aside from their astounding size, their coloring makes them very easy to identify. On the top and sides of its body, the whale shark is a greyish color, with a series of whitish – yellow spots and stripes that give it its distinctive checkerboard-like appearance. Its belly is white. The whale shark’s head is broad and flat. Its nearly 5-foot (1.5m) wide mouth sits almost at the very front of its head, not set well back on the undersurface of their heads and snouts like other shark species, and is lined with 300 rows of tiny teeth, none of which are used to bite or chew its prey – whale sharks are filter feeders. They have small barbels on their snout to help them smell. Their eyes are located a short distance behind the jaw at an angle and are relatively small.
This shark species has two dorsal fins; a larger one located about 2/3 down its back away from its head, and a second smaller one further back near the tail fin. The upper lobe of its tail fin is larger than the lower lobe.
Like all sharks, they use gills to breath. Whale sharks have five large gills that are located above and in front of its pectoral fins. They also have spiracles, or special gill slits, located behind its eyes. On both sides of the upper body, there are three horizontal and parallel ridges that start at the gills and end at the second pectoral fin.
Understanding Whale Sharks
At present, relatively little is understood about the whale shark’s life cycle. No one knows exactly at what size or age the species becomes sexually mature or how many years it can live. There is speculation that males mature by the time they reach lengths between 26 to 29 feet (8–9m) and are between 25 and 30 years old – but even this much theory is not available for the females. The species’ life span is also difficult to access, but it is thought that they can live for 100 years or more.
A bit more is known about whale shark reproduction thanks in great part to a 1995 study. As with most shark species, the whale shark is ovoviviparous, which means the female produces eggs that are fertilized by a male, then, after a specific gestation period, (the gestation length for whale sharks is unknown), gives birth to live young (pups). However, the further details of whale shark reproduction seem to follow a slightly different plan than other shark species. Instead of developing her fertilized eggs all at one time, female whale sharks keep them stored inside their bodies.
According to the 1995 study of a pregnant whale shark that had died after being caught by a fisherman, a single female can carry up to 300 fertilized eggs. These seem to develop in “batches” over a period of time – not all simultaneously as with other shark species. This probably means that they are also born at different times.
Newborn whale sharks measure between 1 – 2 feet (40 cm. – 70 cm.). No one is sure where or how the babies spend the first part of their lives. In 2014, a fisherman in the Maldives found one in his net and brought it to shore. To the delight of tourists, it swam in a resort’s saltwater pool while the fisherman sold his catch. It was then taken back out to sea. Images of the pup, nicknamed ‘Noomaa’ which means blue flower in the native language, were added to the MWRP and Whaleshark.org database in the hopes of tracking it. See above: "Encouraging News" above for more on whale shark tracking.
On the Menu
The species is an oceanic pelagic (lives in open water) fish, but will venture into inshore waters such as coral reefs and lagoons where it feeds on small fish, fish eggs, and small crustaceans such as krill and crab larva, small jellyfish, small squid, and plankton. Whale sharks are one of three living filter-feeding sharks. The other two, only distantly related to whale sharks, are the basking shark and the megamouth shark. According to a study printed in the journal Zoology and cited by the Shark Research Institute, a 20-foot (6 m) whale shark can eat 46 pounds (21 kg) of plankton a day.
Whale sharks are filter feeders. They move through the water with their mouths open, sucking and gulping in its food from the surrounding water column. Once the food is inside its mouth, the water is filtered out through its gills.
What Are They Doing?
This species is highly migratory and appears in different parts of the world at certain times of the year usually coinciding with a massive plankton bloom or a mass spawning of fish or crustaceans.
During the day whale sharks swims at slow speeds (3-3mph /3-5kph) near the water's surface. But, studies have shown at night it can dive to great depths, possibly to feed, but must then must return to the surface to warm and re-oxygenate itself. It is also thought that they dive more deeply when traveling greater distances.
The whale shark is usually solitary, though aggregations of multiple individuals and even very large groups (called a “school” or “shiver”) have been documented. The species is so gentle that it allows divers to approach them. Although it doesn’t like to be touched, many have been hand-tagged for research purposes without incident.
Whale Shark Communication
Little is known about whale shark communication, however, most sharks do communicate with each other. One way, it is believed, is through vibrations. In general, shark species have good hearing especially at lower frequencies – and are able to detect prey at up to 800 ft. (243m) away. Body language probably also plays a part in communication. It is speculated that most communication between sharks is for mating purposes.
Range and Habitat
The species is found in tropical and warm temperate saltwater seas around the world, with the exception of the Mediterranean Sea.
Enemies and Threats
There is documented proof that blue sharks and blue marlin prey on young whale sharks. It is believed that orcas (killer whale) and great white sharks also prey on whale shark pups. But humans are the biggest threat to the species’ survival. See above, ”Conservation” for more information on threats to whale shark survival.
Have you have a personal encounter with a whale shark? Tell us about it!
Destination: Whale Shark
In general, whale shark migration follows ancient patterns. However, it and the food sources that influence it are directly affected by seasonal and other climate changes. Additionally, sometimes they are found just beneath the surface, easy to spot and enjoy from a boat or in the water snorkeling, and at other times they are located at depths too deep even for divers. As with all wildlife, whale sharks can be elusive, but the experience of viewing or swimming with these magnificent fish is well worth the effort. The following are three great places to begin plus 1 that is a little off the beaten track.
A UNESCO World Heritage Site. Whale sharks congregate at Gladden Spit and Silk Cayes Marine Reserve, located on the Belize Barrier Reef System (UNESCO World Heritage Site). This is the only place known in the world where the snappers aggragate to spawn, whale sharks follow them here to feed on the snapper eggs. The sharks can usually be seen from March to June, with April to May being the peak months. Traditionally, the best time to see whale sharks is from two day before to 10 days after the full moon.
Marine Life Bonus: Caribbean reef plus three other shark species, bottlenose dolphins, 6 ray species including both spotted eagle and manta rays, 4 sea turtle species including the hawksbill sea turtle, large fish such as cubera snappers, dog snappers, mutton snappers, barracudas, and colorful coral and reef fish such as the parrotfish.
Land Lubber Wildlife Life Bonus: Iguana, and rainforest species: puma, giant anteater.
Australia: Ningaloo Marine Park - UNESCO World Heritage Site
This marine park is situated along the Ningaloo Coast on Australia’s north - western coast. Whale sharks are a big part of the responsible tourism centered economy of Exmouth, a small town home to some of the earliest whale shark research. Mass spawning of the local corals bring the whale sharks here from mid–March until mid–July to feed.
Time your visit so you don't miss the Ningaloo Whale Shark Festival! Exmouth has held a small, vibrant festival featuring artists, live music, great food, even a "fun run" celebrating the reef and whale sharks on and off for years. The next one is scheduled for May 26-29, 2016. Bring the whole family and take time to see the landlubber wildlife too.
The later part of Ningaloo’s whale shark season overlaps with humpback whale season (June to November). If you find yourself here at other times of the year, you can still catch the sea turtles nesting on Ningaloo’s beaches (November to March), or watch their hatchlings emerge (January to March).
There is also a natural nursery for juvenile reef sharks a short distance from Exmouth near the town of Coral Bay at Skeleton Beach. They can be seen from September to February.
Marine Life Bonus: Dugong, manta ray, whale: humpback, Minke and blue, dolphins: bottlenose, spinner, and Indo–Pacific humpback; sea turtles including green sea, loggerhead, and two other species, and at least four additional shark species: blacktip reef, whitetip reef, and grey reef sharks.
Land Lubber Wildlife Bonus: Emus, Kangaroos.
Philippines: Donsol Bay
This one-time fishing village at the southern tip of Luzon Island in Sorsogon Provence was historically dependent on subsistence whale shark hunting. But in 1998 the local government decided there was a better way to ensure the economic wellbeing of its people. Enter the World Wildlife Fund. They, and a number of tourism stakeholders, turned whale shark hunters into marine life spotters, tour guides, and eco-system protectors, raising living standards and proving to the local community that live marine life is more beneficial to their families than hunting and fishing.
Donsol Bay is now a whale shark protected area. The bay itself has a "no diving - snorkeling only" rule. Not only is this rule good for the sharks, but it is great for shark viewing too. This is where the sharks regularly come to the surface to feed. As long as snorkelers keep their distance, the sharks seem quite content to share their feeding grounds, making for some wonderful, close-up and extended viewing. There is diving nearby at Manta Point.
The WWF verifies that, after a couple of years of reduced sightings, as of 2014, the gentle giants are back in force! So head to Donsol Bay for whale sharks!
The WWF continues to work with the village helping to develop additional diverse responsible wildlife viewing opportunities (see below). In fact, according to WWF's Project Manager in the Philippines, Mr. Raul Burce, Anchored on the three principles of sustainable ecotourism, natural asset protection, direct community benefit and enhanced visitor experience, Donsol's community-based whale shark ecotourism program stands as one of the best sustainable wildlife interaction offerings in Southeast Asia.
While you are there, do not miss the opportunity to take mangrove and evening firefly cruises! Can't envision what a firefly tour could be? Imagine a dark sky, a warm breeze and millions of tiny stars flickering all around you. It is magical.
Marine Life Bonus: Manta Rays and zillions of colorful reef fish.
Landlubber Wildlife Bonus: Fire Flies! And birds, including the endemic whiskered pitta.
The Road Less Traveled
Mozambique: Tofo Beach
Mozambique has had an uneven recent history. However, there are efforts to restore its once vibrant tourist industry and its magnificent natural places – it also is one of the greatest destinations view whale sharks. The best time to see them here is from November to March.
This is also home to the Marine Megafauna Foundation (MMF), conceived at a 2004 New Year's Day braai (barbecue) when business partners Malcolm Warrack (owner of Casa Barry Lodge) and Ray Lang stood on the deck of Malcolm's house and watched about 80 whale sharks swimming at the surface. They wondered why. What are these whale sharks all about?
Today that wonder has turned into one of the most important research facilities for rays and whale sharks on the planet. Their work has become so renowned that after the BBC aired a documentary on manta rays, the MMF's Dr. Andrea Marshall became known world-wide as the "Manta Queen."
Also in residence is the "Whale Shark Whisperer", Dr. Simon J. Pierce. The MMF has their facilities on the grounds of the Casa Barry Lodge. Dr. Marshall and Dr. Pierce welcome questions and conversation with visitors and give regular talks about their work. Lodge guests are invited to "grab a drink" and head for the Casa Barry screening room for the once-in-a-lifetime opportunity to learn and converse with these international marine life research scientists.
Visiting Tofo Beach is not just about science. There is plenty of fun to be had touring off shore and diving or snorkeling, too. Or maybe you'll find yourself adopting a whale shark, or planning a future volunteer vacation. Enjoy this lovely island! The famous Portuguese explorer, Vasco De Gama visited the city of Inhambane (14 miles / 23 km from Tofo Beach) in the early 15th Century. He liked the people so much he dubbed the city, "Terra de Boa Gente" or Land of Good People. Experience it for yourself.
Marine Life Bonus: Manta ray, eagle ray, devil ray, cow nosed ray, bottlenose dolphin, whitetip reef shark, barracuda, and many reef fish including Spanish dancers.
Land Lubber Wildlife Bonus: Mozambique has over 600 bird species; look for migratory shore birds and the beautiful Madagascar bee-eater.
Preparing for Your Whale Shark Adventure
In order to view whale sharks along side them in their habitat, you need to be a good, strong, and experienced swimmer. This species likes open water, read: ocean. Even though the species is a slow swimmer, it’s still a challenge to keep up with one due to the currents.
Be a Responsible Wildlife Tourist
Ensure that you obey the rules and regulations when viewing with whale sharks. If you are in the water with them, swimming too close, touching, or even riding one makes them feel threatened. At best they will avoid future human divers; at worst this can affect their natural behavior, and may cause them to avoid the area. This will negatively impact local people whose economy may now have turned to depend on such things as whale shark tourism (instead of whale shark fishing).
Before traveling to see whale sharks, make sure that you find resorts / hotels that employ responsible tourism best practices. Watch the video from the Maldives Whale Shark Research Program below.
Show and Tell
We want to hear about your whale shark adventures and so do other wildlife lovers!
Send us your stories and photos and we will publish them as possible.
Stories & Information
Simon J. Pierce PhD
Co-founder and Principal Scientist for the Marine Megafauna Foundation (MMF)
Science advisor for Wildbook for Whale Sharks & Director of WildMe
Member IUCN Shark Specialist Group
Follow @Simonpierce See his marine photography.
Ceviche Tours, Isla Mujeres, Mexico.
Follow Ceviche Tours @CevicheTours
Maldives Whale Shark Research Program (MWSRP)
The Belize Tourism Board
Chabil Mar Resort, Placencia, Belize
Whale Shark Information Page
Researched and Presented by:
Erik has been a docent at the Staten Island Zoo since 2009. He is currently pursuing a bachelor’s degree in Biology and looks forward to a career in the care and preservation of wildlife. He is a strong advocate for nature and animals, actively participating in environmental movements and events, and donating regularly to wildlife conservation organizations. He enjoys educating the public about animals and about how each one of us can become more environmentally aware. Erik is a vegan. See more about Erik on our Team page and follow him on Facebook.