Editor’s note: This week Conservation International’s (CI) first virtual reality film, “Valen’s Reef,” debuted at the Cannes Lions International Festival of Creativity; watch the film here. Its spectacular setting — eastern Indonesia’s Bird’s Head region — contains some of the most species-rich waters on Earth. Many of these species were discovered by the same man: record-setting ichthyologist (and frequent CI collaborator) Dr. Gerald Allen. In this interview, Allen reflects on what he’s seen in his 46-year career.
This flasher wrasse species (Paracheilinus rennyae) was discovered by Gerald Allen and Mark Erdmann in 2013. Among the 515 species that Allen has discovered, 11 of them are flasher wrasses. (© CI/Gerald Allen)
Question: You’re one of the world’s foremost ichthyologists. What first sparked your interest in fish?
Answer: When I was 7 years old, my parents gave me a 5-gallon aquarium and a few tropical fish for Christmas; I’ve been fascinated by these creatures ever since. Fishes took a back seat during my teen years when I had an all-consuming passion for football and other sports, but a snorkelling session at Hawai‘i’s Waikiki Beach in 1963 instantly rekindled my interest in fishes. Fortunately, once the interest was revived I had the good fortune to receive guidance from some very influential people in the world of marine biology during my university days.
Q: After hundreds of dives in the waters of the Bird’s Head region, what keeps you coming back?
A: The Bird’s Head and New Guinea in general is such a fascinating place. There is no better place to study marine life and especially to find new species; indeed, I’ve discovered 134 species around the island of New Guinea. The secret is this region’s incredible wealth of habitats concentrated in a relatively small area — everything from mangrove and seagrass communities to atoll coral reefs teeming with fishes. The freshwater fishes of the area are also fascinating, and the Bird’s Head presents a classic example of pristine rainforests existing side by side with rich coral reefs.

Conservation International’s Dayan field station in Raja Ampat, a species-rich archipelago within Indonesia’s Bird’s Head region. (© Shawn Heinrichs)
Q: You hold the world record for counting the most fish species in a single dive. What was different about that day?
A: In April 2012, I recorded 374 species on a single dive at Cape Kri near the Sorido Bay Resort in Raja Ampat [an archipelago within the Bird’s Head region]. It was a perfect, sunny day with no current, 40-meter [131-foot] visibility, and importantly lots of habitat types within a relatively short swim from shore. The count reinforced my belief that the Bird’s Head region is definitely the world’s richest place for fish diversity.
Q: How has the Bird’s Head changed in the years since you started going there?
A: I first visited the Bird’s Head in 1996. Thanks to the efforts of organizations such as CI, the reefs are still in excellent condition, and I honestly have not noticed the deterioration that is characteristic of so many other areas within the Coral Triangle. Sharks are now protected there, which is a huge win for conservation. The use of explosives in fishing, although an ongoing problem, has decreased as a result of better law enforcement.
The biggest change is the increase of tourism. There were no commercial dive operations in 1996; today, at least 40 licensed live-aboard dive boats operate in the area. Dive resorts and numerous homestay eco-resorts have also blossomed throughout the area. I see this as a positive step because reef-based tourism depends on healthy reefs and therefore encourages continuing conservation efforts.
Further reading
- WATCH: ‘Valen’s Reef’
- Amid widespread coral bleaching, this reef is thriving
- Lights, camera, coral: Under the sea, behind the scenes with a VR film crew
- Indonesian government sinks shark poaching boat, creates new dive site
Q: In your 46-year career, you’ve described 515 species new to science and had more than 20 named after you by other researchers. Out of all of those, which one is your favorite, and why?
A: That’s a really difficult question to answer. There have been so many really great discoveries and usually it’s the latest one I’m most excited about. I suppose some of the most memorable have been the 11 species of flasher wrasses I’ve described. They are exceptionally graceful and colorful fishes — in many ways I’d consider them the coral reef equivalent of the exquisite birds of paradise that inhabit New Guinea’s rainforests.
Male flasher wrasses are named for their daily performances just before sunset, when they put on an incredible nuptial display to attract female mates. Underwater photography has always played an essential part in my research, and this group presents the ultimate challenge — their quick movements make them one of the most difficult fishes to photograph.
Q: You are among the world’s most experienced divers, yet sometimes things just go wrong. What’s the most frightening experience you’ve had while diving?
A: Believe me, I’ve had more than a few, but the most sobering took place in southwestern Madagascar in December 2005. It’s a long story, but essentially I surfaced with four other divers on a seamount situated 8 kilometers [5 miles] from shore and our boat was nowhere in sight. We certainly ran through a gauntlet of emotions and physical exertion, but fortunately survived the ordeal — though not before swimming a distance of 18 kilometers [11 miles] to shore, arriving after dark on an uninhabited stretch of coast. That is a day I will never forget.
Q: What’s the most amazing thing you’ve witnessed on a dive?
A: This is difficult to answer because there have been so many amazing sights — usually things the average diver would probably never notice. Invariably, they involved finding new fish species such as the flasher wrasses.

Gerry Allen uses an underwater propulsion device (scooter) to survey reefs during a marine expedition in Indonesia's North Maluku province. (© CI/Sterling Zumbrunn)
Q: What do you see as the biggest threat to marine life in the Bird’s Head region? How about the world?
A: As far as the Bird’s Head is concerned, there are a few significant local threats such as uncontrolled logging and mining, as well as overfishing. On a larger scale, global warming and acidification of the world’s seas are very real threats. I’m ever the optimist, however, so I like to think we can overcome these obstacles.
Q: With CI’s Mark Erdmann, you published “Reef Fishes of the East Indies,” the most comprehensive guide to the region’s fish. What is this book’s use for conservation?
A: The main value of the book in terms of conservation is that it thoroughly documents the fishes of the amazingly rich coral reefs of the East Indian region (a historical term for the vast area stretching from Andaman Islands to the Solomon Islands, including Indonesia and the Philippines). By documenting the regions wealth of fishes, it provides irrefutable evidence of the uniqueness and global importance of this area, and the special need to conserve it.
Gerald Allen has described 515 species new to science and produced over 400 publications on marine and freshwater fish. See the Bird’s Head’s thriving reefs for yourself in CI’s first virtual reality film, “Valen’s Reef.”
Want to read more stories like this? Sign up for email updates. Donate to Conservation International.