When strict guidelines are followed, could spearfishing be the most sustainable way to eat fish? Here, Dr Adam Smith, who has published research on the issue, shares some well-balanced insights on why he chooses to spearfish for his seafood.
LET ME TAKE YOU on my last perfect freedive. I am about 100 metres from the reef edge, in about 20 metres of water and I am floating on the surface looking at colourful coral reefs and abundant baitfish. The visibility underwater is approximately 30 metres, there is a slight current and the temperature is a comfortable 26 degrees Celsius.
There are several pelagic predators chasing the dense schools of blue and yellow baitfish. I know I am in the right location to potentially see a nice fish. My hunting technique is to be relaxed, scan the depths and occasionally dive to midwater (about 10 metres), then hold my position and breath and wait for a curious pelagic fish to investigate me. It may take 10 minutes or three hours of waiting for the desired fish to be in my vicinity. I am startled to see a school of three medium-sized mackerel.
They are moving quickly. I relax, dive silently, avoiding eye contact that may scare them, and wait…I hold my breath.
They circle closer.
I know I must continue to wait until I can be sure. Experience says it is right. I line up my speargun on the closest fish. It is a nice one of about 1.2 metres in length and weighs perhaps 12 kilos. It is when it’s about two-and-a-half metres away, I fire.
It is a lethal shot and the fish quivers and stops. A reef shark rushes over to investigate, but turns away. I quickly bring my catch to the surface. I admire the fish’s colour and form as I dispatch it and bleed it with my knife. I call the boat over to put my fish on ice. It will be very fresh sashimi tonight, with not a part of this incredible animal wasted.
While many divers continue to eat seafood, spearfishing is still regarded by the majority of the diving community as highly controversial. However, as far as methods of catching fish go, research suggests it may be the most sustainable way of harvesting, and consuming, fish.
Scientific research supports the view that spearfishers catch a very small proportion of fish – less than one percent (Australia) to 20 percent (Hawaii) compared to recreational and commercial fishers.
Spearfishers generally target larger edible fish as well as lobsters and octopus. Larger predators are favoured targets of some spearfishers (tuna, mackerel, grouper) although in some areas of the Pacific these species are not targeted because of risk of ciguatera (poisoning as a result of eating toxic flesh) and the favoured targets are herbivorous fish. In some countries, parrotfish is a popular species to target at night because they tend to sleep in areas where they are easy to locate and approach. But targeting these species under these conditions is where spearfishing becomes less sustainable, and attracts a lot of criticism.
Spearfishing, like other forms of fishing, can have rapid and substantial negative effects on target fish populations. Overall, spearfishing is “efficient”, allowing divers to remove larger fish and more biomass per outing than fishers using other recreational techniques such as line fishing.
For example, three years after spearfishing was first allowed in a small marine park in Australia, there was a 54 percent reduction in density and a 27 percent reduction in mean size of coral grouper (Plectropomus spp).
Spearfishing is known to alter fish behaviour, and target fish species within areas that are regularly hunted with spearguns have been shown to exhibit avoidance behaviour when approached by spearfishers.
In my view there are eight common issues of concern raised by the community about spearfishing. These issues differ between geographical locations and individuals:
1. Sustainability: The catch is, or is not, ecologically sustainable (for more information see the infographic on page 23)
2. Safety: Breath-hold diving, and sharks attracted to dying fish and fish blood in the water, make the sport dangerous.
3. Impact on other ocean users: Spearfishers capture or scare fish that are valued by others, including scuba divers and line fishers. In many places, spearfishers may also be competing with people whose livelihoods depend on the fish that foreign/tourist spearfishers may be extracting.
4. Sport: It is wrong to catch fish just for sport. All fish should be eaten.
5. Day vs night: It is wrong to spearfish at night when the fish are sleeping.
6. Snorkel verses scuba: It is unfair to take fish while on scuba.
7. Reef vs pelagic: It is preferable to target pelagic fish rather than reef fish.
8. Conservation: Spearfishers support multiple-use marine parks and conservationists support no-take marine areas.