The vibrant color of the yellow tang adds a depth of beauty to the rainbow of colors on Hawaii’s coral reefs. These fish school, a natural behavior that offers numerous benefits from mating and the search for food to protection against predators.
Their beauty attracts many visitors to snorkel and scuba dive on Hawaii’s living reefs. But it is also the reason why they are the most heavily collected and among the most severely depleted coral reef fish.
Yellow tangs have been captured in limitless numbers from Hawaii’s fragile reefs for decades. Despite the use of nets rather than cyanide, which is widely used elsewhere in fish capture, many yellow tangs don’t survive the trauma of capture and captivity and end up in trash dumpsters.
In January 2010, over 600 yellow tangs, captured for the aquarium trade, were discovered dead in a dumpster in a Hawaii harbor. As outrageous as it was, it’s just a drop in the bucket. An estimated 3%—a minimum of 10 – 20 thousand annually— of all wildlife captured in Hawaii dies before being exported.
The lifespan of coral reef fish is much longer than people may think. For example, many yellow tangs that make it through the initial trials of life will live for decades on a reef and some will even survive over 40 years. In contrast, less than 1% of coral reef wildlife in captivity will survive over a year.
Of newly hatched yellow tangs, 99.9% will become food for other fish as they drift along Hawaii’s offshore waters before settling onto a coral reef. If their chosen reef is one protected from aquarium collecting, they’ll select a spot in a finger coral patch and stay within a few meters of that very spot for many months where they will eat algae, grow and hide from predators.
On this protected reef, an estimated 99% of these young tangs will also be eaten by other fish, which plays an important role in the ocean food web. But a surprising 1% of those who first made it to the reef will survive to be at least 5 to 7 years old, and as an adult fish, will spawn for the first time and contribute to the survival of their species.
As adults they’ll move into shallower areas where they’ll graze on the algae growing on sunlit reefs, keeping everything on the reef in balance. Many of these adults will live for decades on this protected reef
This is the life of a yellow tang in the wild.
But, for those initial open water survivors who happen to choose a reef frequented by aquarium collectors, not only are their days numbered, but the reef will suffer the loss, as well.
They’ll be captured within months, and of those who manage to survive the cumulative stressors of capture and shipping, very few will survive a year in a personal aquarium.
According to experts, next to cyanide related deaths, the highest mortality rates from reef to retail are shipping related and due to stress and starvation. But the mortalities begin with capture and many animals are dying while under the “expert” care of their captors and wholesalers, before they’re ever shipped.
Injuries and stress associated with capture and shipping include:
- Barotrauma, an expanded gas injury to organs and tissues (e.g. swim bladders, brains, eyes) resulting from being surfaced too quickly.
- Organ piercing (known in the trade as “fizzing” or “venting”) used to mitigate barotrauma swim bladder injury at the surface, or underwater for deep water/high dollar value species.
- Unnecessary exposure to air and fin and spine trimming (i.e. cutting tissue, bone and nerves), a practice used by some to avoid the extra packing materials and costs typically used in shipping fish with sharp spines.
- Starvation for 2 – 10 days prior to shipping is used to completely purge the digestive system and facilitate packing and transport in minimal water. This is done solely to reduce freight costs.
For each animal that dies in a personal aquarium, many more are taken from reefs to replace them. Help us keep the yellow tang and other precious coral reef wildlife in the wild!
